articles+ search results

Humans, Magnetic Resonance Imaging methods, Magnetic Resonance Spectroscopy, Phantoms, Imaging, Acceleration, Reproducibility of Results, Heart diagnostic imaging, Image Interpretation, Computer-Assisted methods, and Myocardium

Purpose: Enabling fast and accessible myocardial T 1 mapping is crucial for extending its clinical application. We introduce Open-MOLLI-SMS combining simultaneous multi-slice (SMS) with auto-calibration and variable-rate selective excitation (VERSE)-multiband pulses to obtain all slices in a fast single-shot T 1 mapping sequence.
Methods: Open-MOLLI-SMS was developed by integrating SMS with the open-source method Open-MOLLI previously implemented in Pulseq. Three methods were integrated for Open-MOLLI-SMS: (1) auto-calibration blip patterns to ensure consistency between the data and coil information; (2) a blipped-balanced SSFP (bSSFP) readout to induce controlled aliasing in parallel imaging shifts without disturbing the bSSFP frequency response; and (3) a VERSE-multiband pulse for minimizing the achievable TR and the specific absortion rate (SAR) impact of SMS. Two (SMS2) or three (SMS3) slices were excited simultaneously and encoded with an in-plane acceleration factor of 2. Experiments were performed in the International Society for Magnetic Resonance in Medicine/National Institute of Standards and Technology phantom and five healthy volunteers.
Results: Phantom results show accurate T 1 estimates for reference values between 400 to 2200 ms. Artifacts were visible for Open-MOLLI-SMS3 but not replicated in vivo. In vivo Open-MOLLI-SMS (T 1 SMS2  = 993 ± 10 ms; T 1 SMS3  = 1031 ± 17 ms) provided similar values to mean T 1 single-band Open-MOLLI estimates (T 1 Open-MOLLI  = 1005 ± 47 ms). Open-MOLLI-SMS2 provided the closest estimates to the reference.
Conclusion: This proof-of-principle implementation study demonstrates the feasibility of speeding up T 1 -mapping acquisitions and increasing coverage by combining auto-calibration strategies with a blipped-bSFFP readout and VERSE multiband RF excitation pulses. The proposed methodology was built on the Open-MOLLI mapping sequence, which provides a fast means for prototyping and enables open-source sharing of the method.
(© 2023 The Authors. Magnetic Resonance in Medicine published by Wiley Periodicals LLC on behalf of International Society for Magnetic Resonance in Medicine.)

Animals, Bayes Theorem, Uncertainty, and Anthozoa

Emerging diseases can have devastating consequences for wildlife and require a rapid response. A critical first step towards developing appropriate management is identifying the etiology of the disease, which can be difficult to determine, particularly early in emergence. Gathering and synthesizing existing information about potential disease causes, by leveraging expert knowledge or relevant existing studies, provides a principled approach to quickly inform decision-making and management efforts. Additionally, updating the current state of knowledge as more information becomes available over time can reduce scientific uncertainty and lead to substantial improvement in the decision-making process and the application of management actions that incorporate and adapt to newly acquired scientific understanding. Here we present a rapid prototyping method for quantifying belief weights for competing hypotheses about the etiology of disease using a combination of formal expert elicitation and Bayesian hierarchical modeling. We illustrate the application of this approach for investigating the etiology of stony coral tissue loss disease (SCTLD) and discuss the opportunities and challenges of this approach for addressing emergent diseases. Lastly, we detail how our work may apply to other pressing management or conservation problems that require quick responses. We found the rapid prototyping methods to be an efficient and rapid means to narrow down the number of potential hypotheses, synthesize current understanding, and help prioritize future studies and experiments. This approach is rapid by providing a snapshot assessment of the current state of knowledge. It can also be updated periodically (e.g., annually) to assess changes in belief weights over time as scientific understanding increases. Synthesis and applications: The rapid prototyping approaches demonstrated here can be used to combine knowledge from multiple experts and/or studies to help with fast decision-making needed for urgent conservation issues including emerging diseases and other management problems that require rapid responses. These approaches can also be used to adjust belief weights over time as studies and expert knowledge accumulate and can be a helpful tool for adapting management decisions.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2023 Elsevier Ltd. All rights reserved.)

Solid Waste analysis, Computer Simulation, Conservation of Natural Resources, Models, Theoretical, Ecosystem, Refuse Disposal, and Waste Management

Solid waste disposal is significantly important to maintaining normal operation of both natural and artificial ecosystems. In this study, a kinetic model of solid waste treatment unit (SWTU) was upfront developed based on microbial ecology, system dynamics, cybernetics and digital simulation, which accurately described the relationships and interactions between solid waste decomposition (SWD) processes and biotic/abiotic factors. Then a specific SWTU prototype was designed and built from this kinetic model. A 370-day experiment demonstrated that SWTU maintained normal operation with robust stability and desired dynamic behaviors, and effectively disposed the solid waste. Therefore, this kinetic model was highly valid due to its high structural and behavioral similarity with the prototype. This research could lay a strong theoretical foundation for further closed-loop control as well as optimization of SWTU, and provide scientific guidance to environmental management as well as sustainable development.
Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2023 Elsevier Ltd. All rights reserved.)

Objectives: Thus far, the findings of numerous studies conducted on the accuracy of three-dimensional (3D) printed dental models are conflicting. Therefore, the aim of the network meta-analysis (NMA) is to determine the accuracy of 3D printed dental models compared with digital reference models.
Data: Studies comparing the accuracy of 3D printed full-arch dental models manufactured using different printing techniques to initial STL files were included.
Sources: This study was registered in PROSPERO (CRD42021285863). An electronic search was performed across four databases in November 2021, and search was restricted to the English language.
Study Selection: A systematic search was conducted based on a prespecified search query. 16,303 articles were pooled after the removal of the duplicates. Following study selection and data extraction, 11 eligible studies were included in the NMA in 6 subgroups. The outcomes were specified as trueness and precision and expressed as root mean square (RMS) and absolute mean deviation values. Seven printing technologies were analyzed: stereolithography (SLA), digital light processing (DLP), fused deposition modeling/fused filament fabrication (FDM/FFF), MultiJet, PolyJet, continuous liquid interface production (CLIP), and LCD technology. The QUADAS-2 and GRADE were used to evaluate the risk of bias and certainty of evidence.
Conclusions: SLA, DLP, and PolyJet technologies were the most accurate in producing full-arch dental models.
Clinical Significance: The findings of the NMA suggest that SLA, DLP, and PolyJet technologies are sufficiently accurate for full-arch dental model production for prosthodontic purposes. In contrast, FDM/FFF, CLIP, and LCD technologies are less suitable for manufacturing dental models.
Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Humans, Models, Psychological, and Text Messaging

In an experiment so-termed sociotechnical prototypes based on either a graphical or a textual representation of an envisioned work system were evaluated with regard to their ability to communicate a design vision to people involved in a participatory design process. Results of the study reveal, in line with hypotheses, that the graphical prototype, in contrast to the textual one, was significantly better accepted as well as faster explored and evaluated. Moreover, results support the hypothesis that the graphical sociotechnical prototype helps to build up a more accurate mental representation of the system with regard to its elements (e.g. job roles, tasks). However, no positive effect on the mental representation of the system in terms of the relations between its elements (e.g. which role performs which task?) was found. Finally, practical implications and perspectives for further development of the sociotechnical prototyping approach to envision future work systems are discussed.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2023 Elsevier Ltd. All rights reserved.)

Fluoroscopy methods, Neural Networks, Computer, Area Under Curve, Deglutition, and Deep Learning

Objectives: A videofluoroscopic swallowing study (VFSS) is conducted to detect aspiration. However, aspiration occurs within a short time and is difficult to detect. If deep learning can detect aspirations with high accuracy, clinicians can focus on the diagnosis of the detected aspirations. Whether VFSS aspirations can be classified using rapid-prototyping deep-learning tools was studied.
Methods: VFSS videos were separated into individual image frames. A region of interest was defined on the pharynx. Three convolutional neural networks (CNNs), namely a Simple-Layer CNN, Multiple-Layer CNN, and Modified LeNet, were designed for the classification. The performance results of the CNNs were compared in terms of the areas under their receiver-operating characteristic curves (AUCs).
Results: A total of 18,333 images obtained through data augmentation were selected for the evaluation. The different CNNs yielded sensitivities of 78.8%-87.6%, specificities of 91.9%-98.1%, and overall accuracies of 85.8%-91.7%. The AUC of 0.974 obtained for the Simple-Layer CNN and Modified LeNet was significantly higher than that obtained for the Multiple-Layer CNN (AUC of 0.936) (p < 0.001).
Conclusions: The results of this study show that deep learning has potential for detecting aspiration with high accuracy.
(© 2023. The Author(s) under exclusive licence to Japanese Society for Oral and Maxillofacial Radiology.)

With the use of CAD/CAM technology and rapid prototyping, the opportunities for digitisation and technology are unlimited. 3D printing is going to revolutionise traditional teaching and laboratory methods with rapid progress of new materials, printing technology and machines. Given the large number of options available, one must keep up with the current and emerging technology in order to make benefit of the same. The aim of the study is to assess dental laboratory technicians' knowledge, understanding and practices related the use of 3D printing in dentistry in India.
Methods: From November 2021 to January 2022, a cross-sectional questionnaire-based study was done among dental laboratory technicians in India. Dental technicians were given access to a self-explanatory questionnaire via Google forms link consisting of 12 questions that evaluated their knowledge, awareness and practices regarding 3D printing. The CHERRIES protocol for presenting the findings of the survey was followed. Chi-square test and independent t-test was used for statistical analysis by SPSS version 20.0.
Results: A total of 191 responses were obtained after the questionnaire was circulated to 220 technicians. 171 dental technicians (89.53%) were acquainted of the usage of 3D printing in dentistry.169 (88.48%) Dental technicians preferred 3D printing to traditional procedures. Majority of dental technicians indicated they want to include the 3D printing into their regular work practices and believe digital technology will enhance our profession.
Conclusion: The level of awareness of digital dentistry and 3D printing among the participants is acceptable. Dental technicians at private laboratory showed better understanding about 3D printing as compared to technicians working at dental colleges nevertheless, dental education programmes, webinars and hands-on training should be undertaken that will enhance their expertise of 3D printing.
Competing Interests: No potential conflict of interest relevant to this article was reported.
(© 2023 The Authors.)

Despite being researched for decades, shape-shifting molecular crystals have yet to claim their spot as an actuating materials class among the primary functional materials. While the process for developing and commercializing materials can be lengthy, it inevitably starts with building an extensive knowledge base, which for molecular crystal actuators remains scattered and disjointed. Using machine learning for the first time, we identify inherent features and structure-function relationships that fundamentally impact the mechanical response of molecular crystal actuators. Our model can factor in different crystal properties in tandem and decipher their intersectional and combined effects on each actuation performance. This analysis is an open invitation to utilize interdisciplinary expertise in translating the current basic research on molecular crystal actuators into technology-based development that promotes large-scale experimentation and prototyping.

In recent years biomedical scientific community has been working towards the development of high-throughput devices that allow a reliable, rapid and parallel detection of several strains of virus or microparticles simultaneously. One of the complexities of this problem lies on the rapid prototyping of new devices and wireless rapid detection of small particles and virus alike. By reducing the complexity of microfluidics microfabrication and using economic materials along with makerspace tools (Kundu et al. 2018) it is possible to provide an affordable solution to both the problems of high-throughput devices and detection technologies. We present the development of a wireless, standalone device and disposable microfluidics chips that rapidly generate parallel readouts for selected, possible virus variants from a nasal or saliva sample, based on motorized and non-motorized microbeads detection, and imaging processing of the motion tracks of these beads in micrometers. Microbeads and SARS-CoV-2 COVID-19 Delta variant were tested as proof-of-concept for testing the microfluidic cartridges and wireless imaging module. The Microbead Assay (MA) system kit consists of a Wi-Fi readout module, a microfluidic chip, and a sample collection/processing sub-system. Here, we focus on the fabrication and characterization of the microfluidic chip to multiplex various micrometer-sized beads for economic, disposable, and simultaneous detection of up to six different viruses, microparticles or variants in a single test, and data collection using a commercially available, Wi-Fi-capable, and camera integrated device (Fig. 1).
(© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

This study aims to describe the prototype development and testing of a serious game designed for Brazilian children with diabetes. Following an approach of user-centered design, the researchers assessed game's preferences and diabetes learning needs to develop a Paper Prototype. The gameplay strategies included diabetes pathophysiology, self-care tasks, glycemic management, and food group learning. Diabetes and technology experts (n = 12) tested the prototype during audio-recorded sessions. Next, they answered a survey to evaluate the content, organization, presentation, and educational game aspects. The prototype showed a high content validity ratio (0.80), with three items not achieving the critical values (0.66). Experts recommended improving the game content and food illustrations. This evaluation contributed to the medium-fidelity prototype version, which after testing with diabetes experts (n = 12) achieved high content validity values (0.88). One item did not meet the critical values. Experts suggested increasing the options of outdoor activities and meals. Researchers also observed and video-recorded children with diabetes (n = 5) playing the game with satisfactory interaction. They considered the game enjoyable. The interdisciplinary team plays an important role guiding the designers in the use of theories and real needs of children. Prototypes are a low-cost usability and a successful method for evaluating games.
(Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Scaffolds are implants commonly used to deliver cells, drugs, and genes into the body. Their regular porous structure ensures the proper support for cell attachment, proliferation, differentiated function, and migration. Techniques to fabricate a scaffold include leaching, freeze-drying, supercritical fluid technology, thermally induced phase separation, rapid prototyping, powder compaction, sol-gel, and melt molding. Gene delivery from the scaffold represents a versatile approach to influence the environment for managing cell function. Scaffolds can be used for various tissue engineering purposes, e.g. bone formation, periodontal regeneration, cartilage development, artificial corneas, heart valves, tendon repair, or ligament replacement. Moreover, they are also instrumental in cancer therapy, inflammation, diabetes, heart disease, and wound dressings. Scaffolds provide a platform to extend the delivery of drugs and genetic materials at a controlled timeframe, besides potentially being used to prevent infection upon surgery and other chronic diseases, provided that they can be formulated with specific medicines. This review discusses the need to design advanced functional scaffolds with the potential for modified drug delivery and tissue engineering in a synergistic approach. Special attention is given to works published in 2023 to generate the bibliometric map.
Competing Interests: Declaration of Competing Interest The authors declare no conflict of interest.
(Copyright © 2023. Published by Elsevier B.V.)

Humans, Lignin, Alginates pharmacology, Alginates chemistry, Calcium Phosphates pharmacology, Calcium Phosphates chemistry, Bone Regeneration, Osteogenesis, Printing, Three-Dimensional, Tissue Scaffolds chemistry, and Tissue Engineering methods

The bone is a connective, vascularized, and mineralized tissue that confers protection to organs, and participates in the support and locomotion of the human body, maintenance of homeostasis, as well as in hematopoiesis. However, throughout the lifetime, bone defects may arise due to traumas (mechanical fractures), diseases, and/or aging, which when too extensive compromise the ability of the bone to self-regenerate. To surpass such clinical situation, different therapeutic approaches have been pursued. Rapid prototyping techniques using composite materials (consisting of ceramics and polymers) have been used to produce customized 3D structures with osteoinductive and osteoconductive properties. In order to reinforce the mechanical and osteogenic properties of these 3D structures, herein, a new 3D scaffold was produced through the layer-by-layer deposition of a tricalcium phosphate (TCP), sodium alginate (SA), and lignin (LG) mixture using the Fab@Home 3D-Plotter. Three different TCP/LG/SA formulations, LG/SA ratio 1:3, 1:2, or 1:1, were produced and subsequently evaluated to determine their suitability for bone regeneration. The physicochemical assays demonstrated that the LG inclusion improved the mechanical resistance of the scaffolds, particularly in the 1:2 ratio, since a 15 % increase in the mechanical strength was observed. Moreover, all TCP/LG/SA formulations showed an enhanced wettability and maintained their capacity to promote the osteoblasts' adhesion and proliferation as well as their bioactivity (formation of hydroxyapatite crystals). Such results support the LG inclusion and application in the development of 3D scaffolds aimed for bone regeneration.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2023 The Author(s). Published by Elsevier B.V. All rights reserved.)

Stress, Mechanical, Bioreactors, Polyesters, Tissue Engineering methods, and Mechanotransduction, Cellular physiology

Objective: Tissue engineering (TE) is the study and development of biological substitutes to restore, maintain or improve tissue function. Tissue engineered constructs (TECs) still present differences in mechanical and biological properties compared to native tissue. Mechanotransduction is the process through which mechanical stimulation triggers proliferation, apoptosis, and extracellular matrix synthesis, among other cell activities. Regarding that aspect, the effect of in vitro stimulations such as compression, stretching, bending or fluid shear stress loading modalities have been extensively studied. A fluid flow used to produce contactless mechanical stimulation induced by an air pulse could be easily achieved in vivo without altering the tissue integrity.
Methods: A new air-pulse device for contactless and controlled mechanical simulation of a TECs was developed and validated in this study conducted in the following three phases: 1) conception of the controlled air-pulse device combined with a 3D printed bioreactor; 2) experimental and numerical mechanical characterization of the air-pulse impact by digital image correlation; and 3) achieving sterility and noncytotoxicity of the air-pulse and of the 3D printed bioreactor using a novel dedicated sterilization process.
Results: We demonstrated that the treated PLA (polylactic acid) was noncytotoxic and did not influence cell proliferation. An ethanol/autoclaved sterilization protocol for 3D printed objects in PLA has been developed in this study, enabling the use of 3D printing in cell culture. A numerical twin of the device was developed and experimentally characterized by digital image correlation. It showed a coefficient of determination R 2  = 0.98 between the numerical and averaged experimental surface displacement profiles of the TEC substitute.
Conclusion: The results of the study assessed the noncytotoxicity of PLA for prototyping by 3D printing the homemade bioreactor. A novel sterilization process for PLA was developed in this study based on a thermochemical process. A numerical twin using fluid-structure interaction method has been developed to investigate the micromechanical effects of air pulses inside the TEC, which cannot all be measured experimentally, for instance, wave propagation generated during the air-pulse impact. The device could be used to study the cell response to contactless cyclic mechanical stimulation, particularly in TEC with fibroblasts, stromal cells and mesenchymal stem cells, which have been shown to be sensitive to the frequency and strain level at the air-liquid interface.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2023 Elsevier B.V. All rights reserved.)

Biotechnology, Microtechnology, Printing, Three-Dimensional, Microfluidics methods, and Cell Culture Techniques

Rapid prototyping of microfluidic chips is a key enabler for controlled biotechnology applications in microspaces, as it allows for the efficient design and production of microfluidic systems. With rapid prototyping, researchers and engineers can quickly create and test new microfluidic chip designs, which can then be optimized for specific applications in biotechnology. One of the key advantages of microfluidic chips for biotechnology is the ability to manipulate and control biological samples in a microspace, which enables precise and controlled experiments under well-defined conditions. This is particularly useful for applications such as cell culture, drug discovery, and diagnostic assays, where precise control over the biological environment is crucial for obtaining accurate results. Established methods, for example, soft lithography, 3D printing, injection molding, as well as other recently highlighted innovative approaches, will be compared and challenges as well as limitations will be discussed. It will be shown that rapid prototyping of microfluidic chips enables the use of advanced materials and technologies, such as smart materials and digital sensors, which can further enhance the capabilities of microfluidic systems for biotechnology applications. Overall, rapid prototyping of microfluidic chips is an important enabling technology for controlled biotechnology applications in microspaces, as well as for upscaling it into macroscopic bioreactors, and its continued development and improvement will play a critical role in advancing the field. The review will highlight recent trends in terms of materials and competing approaches and shed light on current challenges on the way toward integrated microtechnologies. Also, the possibility to easy and direct implementation of novel functions (membranes, functionalization of interfaces, etc.) is discussed.
Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2023 Elsevier Ltd. All rights reserved.)

Humans, Software, Pharmacists, Vancomycin, and Drug Monitoring

Background: Different software applications have been developed to support health care professionals in individualized drug dosing. However, their translation into clinical practice is limited, partly because of poor usability and integration into workflow, which can be attributed to the limited involvement of health care professionals in the development and implementation of drug dosing software. This study applied codesign principles to inform the design of a drug dosing software to address barriers in therapeutic drug monitoring using vancomycin as an example.
Methods: Three workshops (face-to-face and online) were conducted by design researchers with pharmacists and prescribers. User journey storyboards, user personas, and prototyping tools were used to explore existing barriers to practice and opportunities for innovation through drug dosing software design. A prototype of the software interface was developed for further evaluation.
Results: Health care professionals (11 hospital pharmacists and 6 prescribers) with ≥2 years of clinical experience were recruited. Confidence and software usability emerged as the main themes. Participants identified a lack of confidence in vancomycin dosing and pharmacokinetic understanding and difficulty in accessing practice guidelines as key barriers that could be addressed through software implementation. Accessibility to information (eg, guidelines and pharmacokinetic resources) and information presentation (eg, graphical) within the dosing software were dependent on the needs and experience of the user. A software prototype with a speedometer-dial visual to convey optimal doses was well received by participants.
Conclusions: The perspectives of health care professionals highlight the need for drug dosing software to be user centered and adaptable to the needs and workflow of end users. Continuous engagement with stakeholders on tool usability, training, and education is needed to promote the implementation in practice.
Competing Interests: The authors declare no conflict of interest.
(Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Microactuators can autonomously convert external energy into specific mechanical motions. With the feature sizes varying from the micrometer to millimeter scale, microactuators offer many operation and control possibilities for miniaturized devices. In recent years, advanced microfluidic techniques have revolutionized the fabrication, actuation, and functionalization of microactuators. Microfluidics can not only facilitate fabrication with continuously changing materials but also deliver various signals to stimulate the microactuators as desired, and consequently improve microfluidic chips with multiple functions. Herein, this cross-field that systematically correlates microactuator properties and microfluidic functions is comprehensively reviewed. The fabrication strategies are classified into two types according to the flow state of the microfluids: stop-flow and continuous-flow prototyping. The working mechanism of microactuators in microfluidic chips is discussed in detail. Finally, the applications of microactuator-enriched functional chips, which include tunable imaging devices, micromanipulation tools, micromotors, and microsensors, are summarized. The existing challenges and future perspectives are also discussed. It is believed that with the rapid progress of this cutting-edge field, intelligent microsystems may realize high-throughput manipulation, characterization, and analysis of tiny objects and find broad applications in various fields, such as tissue engineering, micro/nanorobotics, and analytical devices.
(© 2023 Wiley-VCH GmbH.)

Administration, Cutaneous, Drug Delivery Systems, Lasers, Needles, Dimethylpolysiloxanes chemistry, Polymers chemistry, and Carbon Dioxide

Microneedle-based transdermal drug delivery into the skin has gained attraction for the past few years. An affordable and effective fabrication methodology is required for the development of micron size needle. Manufacturing cost-effective microneedle patches in batch production is a challenging process. In this work, we proposed a cleanroom-free technique for fabrication of conical and pyramidal geometry of microneedle array for transdermal drug delivery. Using the COMSOL Multiphysics tool, the mechanical strength of the designed microneedle array under axial, bending, and buckling loads for the geometries during skin insertion was investigated. A CO 2 laser and polymer molding technique are used to fabricate 10 × 10 designed microneedle array structure. On an acrylic sheet, a designed pattern is engraved to produce a 20 mm × 20 mm sharp conical and pyramidal shape master mold. We successfully created a biocompatible polydimethylsiloxane (PDMS) microneedle patch with an average height of 1200 µm, base diameter of 650 µm, and a tip diameter of 50 µm using acrylic master mold. According to structural simulation analysis, the microneedle array will experience resultant stress that is within a safe range. The mechanical stability of the fabricated microneedle patch was investigated using hardness test and universal testing machine. The depth of penetration studies were performed in an in vitro Parafilm ® M model by manual compression tests and its detailed insertion depth was reported. The developed master mold is efficient to replicate several polydimethylsiloxane microneedle patches. The proposed combined method of laser processing and molding mechanism is simple and low-cost for rapid prototyping of microneedle array.
(© 2023. Controlled Release Society.)

Microplasma UV lamps have recently emerged as viable excimer-based sources of UV radiation, garnering significant attention during the recent COVID-19 pandemic for their use in disinfection applications because of their ability to emit human-safe far-UVC (200-240 nm) spectrums. An accurate model to simulate the radiation profile of microplasma UV lamps is of paramount importance to develop efficient microplasma lamp-implemented systems. We developed a 3D numerical model of microplasma UV lamps using the ray optics method. The simulation results for lamp irradiance and fluence rate were experimentally validated with standard optical radiometry and actinometry measurements, respectively. To improve the optical efficiency of microplasma lamps, an in-depth analysis of radiation behavior inside the standard commercially available lamp was performed using the geometrical optics method, and several potential scenarios were explored. A 2D modeling of an individual microcavity indicated that the current common lamp design can be significantly improved by preventing radiation loss, and small modifications in optical design can greatly increase the energy performance of the system. Based on the findings of this study, several virtual design concepts were proposed, and their performances were numerically compared with that of the original design of commercial microplasma lamps. The developed model can potentially be integrated with hydrodynamic and kinetic models for the virtual prototyping of complex photoreactors operating with UV microplasma lamps.
Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(© 2023 Elsevier Ltd. All rights reserved.)

Ex vivo hemocompatibility testing is a vital element of preclinical assessment for blood-contacting medical devices. Current approaches are resource intensive; thus, we investigated the feasibility of accelerating hemocompatibility testing by standardizing the number of pump exposures in loops of various sizes. Three identical blood loops were constructed, each with a custom-molded reservoir able to facilitate large-volume expansion. Using the HVAD rotary blood pump operating at 5 L·min-1 and 100 mmHg, three test volumes (80, 160, and 320 ml) were circulated for 4000 pump exposures. Blood sampling was performed at individualized intervals every one-sixth of total duration for the assessment of hemolysis and von Willebrand Factor (vWF) degradation. While steady increases in hemolysis (~24 mg·dl-1) were identified in all tests at completion, loop volume was not a primary discriminator. The normalized index of hemolysis did not vary significantly between loops (4.2-4.9 mg·100 L-1). vWF degradation progressively occurred with duration of testing to a similar extent under all conditions. These data support an accelerated approach to preclinical assessment of ex vivo blood damage. Adopting this approach enables: enhanced efficiency for rapid prototyping; reduced ex vivo blood aging, and; greater utility of blood, which is presently limited if 450 ml loops are desired.
Competing Interests: Disclosure: The authors have no conflicts of interest to report.
(Copyright © ASAIO 2023.)

Humans, Hand, Public Health, Family Characteristics, Hand Disinfection methods, Soaps, and Health Behavior

Handwashing with soap is a widely advocated public health measure, but seldom practiced, partly because it is often difficult (especially outside of rich Western country contexts) to make both soap and water readily available in relevant situations. This study used both Behaviour Centred Design and Human Centred Design to guide development of a novel hand cleansing technology appropriate for the context of post-toilet hand cleansing in resource-poor societies. Extensive prototyping and field testing resulted in the pilot production of 'tab' soap, a small but durable single-use, decomposable substrate embedded with soap. It can be produced in dispenser roll or tear-off formats. With this affordable solution, one may use soap without worrying about contamination pretty much anytime and anywhere. A small-scale field test showed that all poor households in rural and peri-urban areas in Tanzania included in the proof-of-concept study (N = 12 households) would use the product reliably over the medium term. Tab soap awaits full-scale production and marketing but could make hand cleansing a more popular practice around the world.
Competing Interests: The authors have an interest in the innovation becoming available at scale and are working to develop partnerships, apply for grants and otherwise support such progress though no financial gain is expected. While a product is in development, there are currently no patents associated with this research to declare. This does not alter our adherence to PLOS ONE policies on sharing data and materials.
(Copyright: © 2023 Brial et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Fast imaging methods are needed to promote widespread clinical adoption of Ultrasound Tomography (UST), and more widely available UST hardware could support the experimental validation of new measurement configurations. In this work, an open-source 256-element transducer ring array was developed (morganjroberts.github.io/open-UST) and manufactured using rapid prototyping, for only £2k. Novel manufacturing techniques were used, resulting in a 1.17° mean beam axis skew angle, a 104 μm mean element position error, and a ±13.6 μm deviation in matching layer thickness. The nominal acoustic performance was measured using hydrophone scans and watershot data, and the 61.2 dB SNR, 55.4° opening angle, 10.2 mm beamwidth and 54% transmit-receive bandwidth (-12 dB), were found to be similar to existing systems, and compatible with state of the art full-waveform-inversion image reconstruction methods. The inter-element variation in acoustic performance was typically <10% without using normalisation, meaning that the elements can be modelled identically during image reconstruction, removing the need for individual source definitions based on hydrophone measurements. Finally, data from a phantom experiment was successfully reconstructed. These results demonstrate that the open-UST system is accessible for users, and suitable for UST imaging research.

Humans, Child, User-Centered Design, Indonesia, Mobile Applications, Telemedicine methods, and Leukemia

Background: A mobile health (mHealth) application can encourage parents and pediatric patients to be involved in caring for their child's health condition by providing the ability to identify and actively manage chemotherapy-related symptoms in their child. Several monitoring systems available today are diverse in features and system basis. This study aimed to develop and trial the Chemo Assist for Children (CAC) mHealth application for symptom management in children with acute lymphoblastic leukemia (ALL).
Methods: In this study, the development of the CAC application went through multiple phases and methods. Study phases included: (1) development of the application's feature based on the need assessment, (2) creation of content of application based on literature review, (3) develop prototyping of CAC, (4) expert review and feedback on the application content, (5) usability testing by targeted end-user.
Results: Based on need assessment, it was determined that parents with leukemia children were interested in symptom management of chemotherapy and preferred mobile applications. Therefore, a mHealth application was designed to include features to identify symptoms and provide recommendation strategies to manage the symptom. Usability evaluation by end-user revealed that mHealth is a valid, accessible, and appropriate application for users.
Conclusions: The CAC mHealth application developed can meet the needs of technology users to identify symptoms and manage chemotherapy-related symptoms in children with ALL. The CAC mHealth application can accommodate data not recorded at out-of-hospital care, increase the independence of symptom management, and improve communication between parents of children with ALL and health workers.
(© 2023. The Author(s).)

Background: Fatigue is an important symptom for many patients, including patients with kidney disease. Cognitive biases, such as attentional bias and self-identity bias, are thought to influence fatigue. Cognitive bias modification (CBM) training is a promising technique to counter fatigue.
Objective: We aimed to evaluate a CBM training among patients with kidney disease and health care professionals (HCPs) and assess acceptability and applicability in the clinical setting using an iterative design process to evaluate expectations and experiences with the training.
Methods: This was a longitudinal, qualitative, and multiple stakeholder-perspective usability study in which we interviewed end users and HCPs during the prototyping phase and after the end of training. We conducted semistructured interviews with 29 patients and 16 HCPs. The interviews were transcribed and analyzed thematically. Next to a general evaluation of the training, the acceptability of the training was evaluated using the Theoretical Framework of Acceptability, and applicability was assessed by evaluating obstacles and solutions for implementation in the kidney care setting.
Results: Generally, participants were positive about the training and its applicability. The biggest negatives were doubts about effectiveness and annoyance about the repetitive character of CBM. Acceptability was judged with a mixed evaluation, with a negative evaluation of perceived effectiveness; mixed results for burden, intervention coherence, and self-efficacy; and positive results for affective attitude, ethicality, and opportunity costs. Barriers for applicability were patients' varying computer skills, subjectivity of fatigue, and integration with regular treatment (eg, the role of HCPs). Possible solutions included assigning representatives among nurses, offering training on an app, and providing assistance via a help desk. The iterative design process, including repeated waves of testing user expectations and experiences, yielded complementary data.
Conclusions: To the best of our knowledge, this study is the first to introduce a CBM training targeting fatigue. Furthermore, this study provides one of the first user evaluations of a CBM training, both among patients with kidney disease and their care providers. Overall, the training was evaluated positively, although acceptability showed mixed results. Applicability was positive although barriers were identified. The proposed solutions require further testing, preferably following the same frameworks, as the iteration in this study contributed positively to the quality of the training. Therefore, future research should follow the same frameworks and consider stakeholders and end users in eHealth intervention design.
(©Jody Geerts, Marcel Pieterse, Goos Laverman, Femke Waanders, Nicole Oosterom, Jacqueline Slegten, Elske Salemink, Christina Bode. Originally published in JMIR Formative Research (https://formative.jmir.org), 29.05.2023.)

Humans, Materials Testing, Zirconium, Printing, Three-Dimensional, Crowns, and Dental Restoration Failure

Aim: The aim of the present study was the evaluation of the in vitro performance and fracture force of 3D-printed anterior implant-supported temporary partial dentures (TPDs) with different filler content.
Materials and Methods: Identical anterior resin-based TPDs (tooth sites 11 to 13; n = eight per material) were 3D printed from methacrylate resins with different filler content. A cartridge polymethyl methacrylate (PMMA) material was used as a reference. After temporary cementation, combined thermal cycling and mechanical loading (TCML) was performed on all the restorations to mimic clinical application. Behavior during TCML and fracture force was determined, and failures were analyzed. Data were statistically investigated (Kolmogorov-Smirnov test, one-way ANOVA; post hoc Bonferroni, Kaplan-Meier survival; α = 0.05).
Results: Failure during TCML varied between three failures and total failure during loading time. Mean survival time varied between 93 ± 206 x 103 cycles and 329 ± 84 x 103 cycles. Significantly different survival cycles between the individual materials could be determined (Mantel Cox log-rank test: chi-square: 21,861; degrees of freedom (df) = 4, P < 0.001). A correlation between filler level and survival cycles could be found (Pearson: 0.186, P = 0.065). Fracture values of the surviving TPDs varied between 499 and 835 N. Failures were characterized by fracture of the connector (n = 24) followed by fractures at the abutment (n = 10).
Conclusions: TDPs showed different filler-dependent survival. Individual 3D-printed materials provided comparable or even better performance than a standard cartridge system and might be sufficient for temporary application of at least half a year.

Female, Humans, Spectroscopy, Fourier Transform Infrared, Fluorouracil, Polyesters, and Uterine Cervical Neoplasms drug therapy

Solid lipid nanoparticles (SLNs) are used extensively to achieve site-specific drug delivery with improved bioavailability and reduced toxicity. This work focused on a new approach to provide site-specific stimuli-responsive delivery of SLNs loaded within thermo-sonic nano-organogel (TNO) variants to deliver the model chemotherapeutic agent 5-FU in treating cervical cancer. Pharmaceutically stable nanospherical SLNs comprising poly-L-lactic acid (PLA), palmitic acid (PA), and polyvinyl alcohol (PVA) were prepared and incorporated into TNO variants augmented by external thermal and ultrasound stimuli for release of 5-FU in the cervix. Results revealed that rate-modulated 5-FU release was achieved from SLNs (particle size =450.9 nm; PDI =0.541; zeta potential =-23.2 mV; %DL =33%) within an organogel upon exposure to either a single (thermo-) and/or both (thermo-sonic) stimuli. 5FU was released from all TNO variants with an initial burst on day 1 followed by sustained release over 14 days. TNO 1 provided desirable release over 15 days (44.29% vs. 67.13% under single (T) or combined (TU) stimuli, respectively). Release rates were primarily influenced by the SLN:TO ratio in tandem with biodegradation and hydrodynamic influx. Biodegradation by day 7 revealed that variant TNO 1 (1:5) released 5FU (46.8%) analogous to its initial mass than the other TNO variants (i.e., ratios of 2:5 and 3:5). FT-IR spectra revealed assimilation of the system components and corroborative with the DSC and XRD analysis (i.e., in ratios of PA:PLA 1:1 and 2:1). In conclusion, the TNO variants produced may be used as a potential stimuli-responsive platform for the site-specific delivery of chemotherapeutic agents such as 5-FU to treat cervical cancer.
(© 2023. The Author(s).)

The aim of this study was to introduce a new computer guided technique for debulking and contouring the craniofacial fibrous dysplasia involving the fronto-orbital and fronto-cranial regions. Computer-guided contouring was performed using a modified patient-specific surgical depth guide for six patients with craniofacial fibrous dysplasia involving the fronto-orbital and fronto-cranial regions. Virtual planning was performed to determine the desired amount of bone removal and construct the patient-specific surgical depth guide. Then, the guide was printed using rapid prototyping. In the surgical theatre, the guide was seated in position. Implant drills were inserted through the created depth holes according to the planned fixed depth to create depth holes. Finally, the bone in between the created holes was removed using cutting discs, bone chisels and surgical burs. Satisfaction with facial aesthetics was evaluated by the patients using a Likert scale, and by the surgeons using the Whitaker rating scale. The surgical procedures were uneventful for all the patients. All the patients were satisfied with the post-operative facial esthetics and categorized as category I Whitaker rating scale. Patient-specific surgical guide technique for recontouring of fronto-orbital and fronto-cranial fibrous dysplasia can be considered an accurate substitution technique that overcomes the drawbacks of the unpredictable conventional one. Further investigations are required.
Competing Interests: Declaration of competing interest None.
(Copyright © 2023 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

The transition of additive manufacturing (AM) from a technique for rapid prototyping to one for manufacturing of near net or net components has been led by the development of methods that can repeatedly fabricate quality parts. High-speed laser sintering and the recently developed multi-jet fusion (MJF) processes have seen quick adoption from industry due to their ability to produce high-quality components relatively quickly. However, the recommended refresh ratios of new powder led to notable amounts of used powder being discarded. In this research, polyamide-11 powder, typically used in AM, was thermally aged to investigate its properties at extreme levels of reuse. The powder was exposed to 180 °C in air for up to 168 h and its chemical, morphological, thermal, rheological, and mechanical properties were examined. To decouple the thermo-oxidative aging phenomena from AM process related effects, such as porosity, rheological and mechanical properties characterisation was performed on compression-moulded specimens. It was found that exposure notably affected the properties of both the powder and the derived compression-moulded specimens within the first 24 h of exposure; however, consecutive exposure did not have a significant effect.

Humans, Records, Electronic Health Records, Medical Order Entry Systems, and Decision Support Systems, Clinical

Alerting systems have a strong potential to improve quality of care in hospital by ensuring that clinicians provide more effective and timely care to their patients. Many systems have been implemented but often fail to unleash their full potential due to the problem of alert fatigue. As an attempt to reduce this fatigue we have developed a targeted alerting system ensuring only the concerned clinicians receives the alerts. The conception of the system went through several steps going from the identification of the requirement, the prototyping and implementation into several systems. The results present the different parameters taken into consideration and developed frontends. We finally discuss the important considerations of alerting system, such as the necessity of a governance. The system still needs a formal evaluation to validate that it responds to its promises before being deployed more largely.

Humans, Computer Simulation, Engineering, and User-Computer Interface

The aim of this work is to develop and evaluate a multi-stage procedure model for the identification of use problems and optimization of usability using biosignal data. The concept is divided into 5 steps: 1. static analysis of data to identify use problems; 2. conducting interviews within the context of use and requirements analysis to investigate problems in more detail; 3. developing new interface concepts to implement the requirements and a prototype of an interface including dynamic visualization of data; 4. formative evaluation using an unmoderated remote usability test; 5. usability test with realistic scenarios and influencing factors in the simulation room. The concept was evaluated in the ventilation setting as an example. The procedure allowed the identification of use problems in the ventilation of patients as well as the development of suitable concepts and their evaluation to counteract use problems. To relieve users, ongoing analyses of biosignals with respect to the use problem are to be carried out. To overcome technical barriers, further development is needed in this area.

Three-dimensional (3D) printing is one of the promising technologies for the fabrication of microstructures due to its versatility, ease of fabrication, and low cost. However, the direct use of 3D-printed microstructure as a microchannel is still limited due to its surface property, biocompatibility, and transmittance. As an alternative, rapid prototyping of poly(dimethylsiloxane) (PDMS) from 3D-printed microstructures ensures both biocompatibility and efficient fabrication. We employed 3D-printed molds fabricated using horizontal and vertical arrangement methods with different slice thicknesses in a digital light projection (DLP)-based 3D printing process to replicate PDMS microchannels. The replicated PDMS structures were investigated to compare their optical transmittances and surface roughness. Interestingly, the optical transmittance of PDMS from the 3D-printed mold was significantly increased via bonding two single PDMS layers. To evaluate the applicability of the replicated PDMS devices from the 3D-printed mold, we performed droplet generation in the PDMS microchannels, comparing the same device from a conventional Si-wafer mold. This study provides a fundamental understanding of prototyping microstructures from the DLP-based 3D-printed mold.
Competing Interests: The authors declare no competing financial interest.
(© 2023 The Authors. Published by American Chemical Society.)

Objective: The objective of this paper is to describe the techniques and process of developing and testing a take-home surgical anastomosis simulation model.
Design: Through an iterative process, a simulation model was customized and designed to target specific skill development and performance objectives that focused on anastomotic techniques in thoracic surgery and consist of 3D printed and silicone molded components. Various manufacturing techniques such as silicone dip spin coating and injection molding have been described in this paper and explored as part of the research and development process. The final prototype is a low-cost, take-home model with reusable and replaceable components.
Setting: The study took place at a single-center quaternary care university-affiliated hospital.
Participants: The participants included in the model testing were 10 senior thoracic surgery trainees who completed an in-person training session held during an annual hands- on thoracic surgery simulation course. Feedback was then collected in the form of an evaluation of the model from participants.
Results: All 10 participants had an opportunity to test the model and complete at least 1 pulmonary artery and bronchial anastomosis. The overall experience was rated highly, with minor feedback provided regarding the set- up and fidelity of the materials used for the anastomoses. Overall, the trainees agreed that the model was suitable for teaching advanced anastomotic techniques and expressed an interest in being able to use this model to practice skill development.
Conclusions: Developed simulation model can be easily reduced, with customized components that accurately simulate real-life vascular and bronchial components suitable for training of anastomoses technique amongst senior thoracic surgery trainees.
(Copyright © 2023. Published by Elsevier Inc.)

Six acrylamide resins, derived from l-phenylalanine and l-leucine, are designed for application in digital light processing (DLP) printers to obtain biodegradable thermoset polymers. The acrylamide copolymers are prepared under light irradiation at 405 nm and thermal post-curing processes. Low molecular weight poly(ethylene glycol)diacrylate (PEGDA) and N,N-dimethylacrylamide (DMAM), both liquid resins, are used as co-monomers and diluents for the amino acid-derived acrylamide solubilization. The presence of two phenylalanine units and two ester groups in the acrylamide monomer accuses a fast degradation rate in hydrolytic medium in 90 days. The residual products leached in the aqueous media prove to be non-cytotoxic, when 3D-printed samples are cultured with osteoblast cells (MG63), which represents an advantage for the safe disposal of printer waste materials. The scaled-up pieces derived from l-phenylalanine and diethylene glycol, as amino acid-derived acrylamide (named compound C), PEGDA and DMAM, present high dimensional stability after DLP printing of complex structures used as testing samples. Layers of 50 µm of thickness are well cohesive having isotropic behavior, as demonstrated with tensile-strain measurements performed in X-Y-Z (plane) directions. The compound C, which contains phenylalanine amino acid, reveals a promising potential to replace non-biodegradable acrylate polymers used in prototyping systems.
(© 2023 Wiley-VCH GmbH.)

Humans, Porosity, Electrodes, and Graphite

Flexible pressure sensors are widely applied in tactile perception, fingerprint recognition, medical monitoring, human-machine interfaces, and the Internet of Things. Among them, flexible capacitive pressure sensors have the advantages of low energy consumption, slight signal drift, and high response repeatability. However, current research on flexible capacitive pressure sensors focuses on optimizing the dielectric layer for improved sensitivity and pressure response range. Moreover, complicated and time-consuming fabrication methods are commonly applied to generate microstructure dielectric layers. Here, we propose a rapid and straightforward fabrication approach to prototyping flexible capacitive pressure sensors based on porous electrodes. Laser-induced graphene (LIG) is produced on both sides of the polyimide paper, resulting in paired compressible electrodes with 3D porous structures. When the elastic LIG electrodes are compressed, the effective electrode area, the relative distance between electrodes, and the dielectric property vary accordingly, thereby generating a sensitive pressure sensor in a relatively large working range (0-9.6 kPa). The sensitivity of the sensor is up to 7.71%/kPa -1 , and it can detect pressure as small as 10 Pa. The simple and robust structure allows the sensor to produce quick and repeatable responses. Our pressure sensor exhibits broad potential in practical applications in health monitoring, given its outstanding comprehensive performance combined with its simple and quick fabrication method.

Flexible electronics have gained great attention in recent years owing to their promising applications in biomedicine, sustainable energy, human-machine interaction, and toys for children. Paper mainly produced from cellulose fibers is attractive substrate for flexible electronics because it is biodegradable, foldable, tailorable, and light-weight. Inspired by daily handwriting, the rapid prototyping of sensing devices with arbitrary patterns can be achieved by directly drawing conductive inks on flat or curved paper surfaces; this provides huge freedom for children to design and integrate "do-it-yourself (DIY)" electronic toys. Herein, viscous and additive-free ink made from Ti 3 C 2 T X MXene sediment is employed to prepare disposable paper electronics through a simple ball pen drawing. The as-drawn paper sensors possess hierarchical microstructures with interweaving nanosheets, nanoflakes, and nanoparticles, therefore exhibiting superior mechanosensing performances to those based on single/fewer-layer MXene nanosheets. As proof-of-concept applications, several popular children's games are implemented by the MXene-based paper sensors, including "You say, I guess," "Emotional expression," "Rock-Paper-Scissors," "Arm wrestling," "Throwing game," "Carrot squat," and "Grab the cup," as well as a DIY smart whisker for a cartoon mouse. Moreover, MXene-based paper sensors are safe and disposable, free from producing any e-waste and hazard to the environment.
(© 2023 Wiley-VCH GmbH.)

The performance of two-dimensional (2D) materials is promising for electronic, photonic, and sensing devices since they possess large surface-to-volume ratios, high mechanical strength, and broadband light sensitivity. While significant advances have been made in synthesizing and transferring 2D materials onto different substrates, there is still the need for scalable patterning of 2D materials with nanoscale precision. Conventional lithography methods require protective layers such as resist or metals that can contaminate or degrade the 2D materials and deteriorate the final device performance. Current resist-free patterning methods are limited in throughput and typically require custom-made equipment. To address these limitations, we demonstrate the noncontact and resist-free patterning of platinum diselenide (PtSe 2 ), molybdenum disulfide (MoS 2 ), and graphene layers with nanoscale precision at high processing speed while preserving the integrity of the surrounding material. We use a commercial, off-the-shelf two-photon 3D printer to directly write patterns in the 2D materials with features down to 100 nm at a maximum writing speed of 50 mm/s. We successfully remove a continuous film of 2D material from a 200 μm × 200 μm substrate area in less than 3 s. Since two-photon 3D printers are becoming increasingly available in research laboratories and industrial facilities, we expect this method to enable fast prototyping of devices based on 2D materials across various research areas.

Microfluidics, Cell Culture Techniques, Hydrophobic and Hydrophilic Interactions, Endothelial Cells, and Endothelium, Vascular

On-chip vascular microfluidic models provide a great tool to study aspects of cardiovascular diseases in vitro. To produce such models, polydimethylsiloxane (PDMS) has been the most widely used material. For biological applications, its hydrophobic surface has to be modified. The major approach has been plasma-based surface oxidation, which has been very challenging in the case of channels enclosed within a microfluidic chip. The preparation of the chip combined a 3D-printed mold with soft lithography and commonly available materials. We have introduced the high-frequency low-pressure air-plasma surface modification of seamless channels enclosed within a PDMS microfluidic chip. The plasma treatment modified the luminal surface more uniformly than in previous works. Such a setup enabled a higher degree of design freedom and a possibility of rapid prototyping. Further, plasma treatment in combination with collagen IV coating created a biomimetic surface for efficient adhesion of vascular endothelial cells as well as promoted long-term cell culture stability under flow. The cells within the channels were highly viable and showed physiological behavior, confirming the benefit of the presented surface modification.

Objectives: We aimed to develop a video animation knowledge translation (KT) resource to explain the purpose, use and importance of evidence synthesis to the public regarding healthcare decision-making.
Methods: We drew on a user-centred design approach to develop a spoken animated video (SAV) by conducting two cycles of idea generation, prototyping, user testing, analysis, and refinement. Six researchers identified the initial key messages of the SAV and informed the first draft of the storyboard and script. Seven members of the public provided input on this draft and the key messages through think-aloud interviews, which we used to develop an SAV prototype. Seven additional members of the public participated in think-aloud interviews while watching the video prototype. All members of the public also completed a questionnaire on perceived usefulness, desirability, clarity and credibility. We subsequently synthesised all data to develop the final SAV.
Results: Researchers identified the initial key messages as 1) the importance of evidence synthesis, 2) what an evidence synthesis is and 3) how evidence synthesis can impact healthcare decision-making. Members of the public rated the initial video prototype as 9/10 for usefulness, 8/10 for desirability, 8/10 for clarity and 9/10 for credibility. Using their guidance and feedback, we produced a three-and-a-half-minute video animation. The video was uploaded on YouTube, has since been translated into two languages, and viewed over 12,000 times to date.
Conclusions: Drawing on user-centred design methods provided a structured and transparent approach to the development of our SAV. Involving members of the public enhanced the credibility and usefulness of the resource. Future work could explore involving the public from the outset to identify key messages in developing KT resources explaining methodological topics. This study describes the systematic development of a KT resource with limited resources and provides transferrable learnings for others wishing to do similar.
Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
(© The Author(s) 2023.)

Humans, Knee Joint, Knee, Biomechanical Phenomena, Ligaments, Articular, Range of Motion, Articular, and Robotic Surgical Procedures

Medical device regulatory standards are increasingly incorporating computational modelling and simulation to accommodate advanced manufacturing and device personalization. We present a method for robust testing of engineered soft tissue products involving a digital twin paradigm in combination with robotic systems. We developed and validated a digital twin framework for calibrating and controlling robotic-biological systems. A forward dynamics model of the robotic manipulator was developed, calibrated, and validated. After calibration, the accuracy of the digital twin in reproducing the experimental data improved in the time domain for all fourteen tested configurations and improved in frequency domain for nine configurations. We then demonstrated displacement control of a spring in lieu of a soft tissue element in a biological specimen. The simulated experiment matched the physical experiment with 0.09 mm (0.001%) root-mean-square error for a 2.9 mm (5.1%) length change. Finally, we demonstrated kinematic control of a digital twin of the knee through 70-degree passive flexion kinematics. The root-mean-square error was 2.00°, 0.57°, and 1.75° degrees for flexion, adduction, and internal rotations, respectively. The system well controlled novel mechanical elements and generated accurate kinematics in silico for a complex knee model. This calibration method could be applied to other situations where the specimen is poorly represented in the model environment (e.g., human or animal tissues), and the control system could be extended to track internal parameters such as tissue strain (e.g., control knee ligament strain). Further development of this framework can facilitate medical device testing and innovative biomechanics research.
Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2023. Published by Elsevier Ltd.)

Humans, Child, Muscle, Skeletal physiology, Tendons, Ankle, Ankle Joint, and Cerebral Palsy

Neuromusculoskeletal models can be used to evaluate aberrant muscle function in cerebral palsy (CP), for example by estimating muscle and joint contact forces during gait. However, to be accurate, models should include representative musculotendon parameters. We aimed to estimate personalised parameters that capture the mechanical behaviour of the plantarflexors in children with CP and typically developing (TD) children. Ankle angle (using motion capture), torque (using a load-cell), and medial gastrocnemius fascicle lengths (using ultrasound) were measured during slow passive ankle dorsiflexion rotation for thirteen children with spastic CP and thirteen TD children. Per subject, the measured rotation was input to a scaled OpenSim model to simulate the torque and fascicle length output. Musculotendon model parameters were personalised by the best match between simulated and experimental torque-angle and fascicle length-angle curves according to a least-squares fit. Personalised tendon slack lengths were significantly longer and optimal fibre lengths significantly shorter in CP than model defaults and than in TD. Personalised tendon compliance was substantially higher in both groups compared to the model default. The presented method to personalise musculotendon parameters will likely yield more accurate simulations of subject-specific muscle mechanics, to help us understand the effects of altered musculotendon properties in CP.
(© 2022. The Author(s).)

Photonic integrated circuits (PICs) can drastically expand the capabilities of quantum and classical optical information science and engineering. PICs are commonly fabricated using selective material etching, a subtractive process. Thus, the chip's functionality cannot be substantially altered once fabricated. Here, we propose to exploit wide-bandgap non-volatile phase-change materials (PCMs) to create rewritable PICs. A PCM-based PIC can be written using a nanosecond pulsed laser without removing any material, akin to rewritable compact disks. The whole circuit can then be erased by heating, and a new circuit can be rewritten. We designed a dielectric-assisted PCM waveguide consisting of a thick dielectric layer on top of a thin layer of wide-bandgap PCMs Sb 2 S 3 and Sb 2 Se 3 . The low-loss PCMs and our designed waveguides lead to negligible optical loss. Furthermore, we analyzed the spatiotemporal laser pulse shape to write the PICs. Our proposed platform will enable low-cost manufacturing and have a far-reaching impact on the rapid prototyping of PICs, validation of new designs, and photonic education.

Humans, Printing, Three-Dimensional, Prostheses and Implants, Arthroplasty, Upper Extremity surgery, Fractures, Bone surgery, and Surgery, Computer-Assisted

The use of three-dimensional (3-D) technology in upper extremity surgery has the potential to revolutionize the way that hand and upper limb procedures are planned and performed. 3-D technology can assist in the diagnosis and treatment of conditions, allowing virtual preoperative planning and surgical templating. 3-D printing can allow the production of patient-specific jigs, instruments and implants, allowing surgeons to plan and perform complex procedures with greater precision and accuracy. Previously, cost has been a barrier to the use of 3-D technology, which is now falling rapidly. This review article will discuss the current status of 3-D technology and printing, including its applications, ethics and challenges in hand and upper limb surgery. We have provided case examples to outline how clinicians can incorporate 3-D technology in their clinical practice for congenital deformities, management of acute fracture and malunion and arthroplasty.

Models, Molecular, Neural Networks, Computer, Benchmarking, and Drug Discovery

Graph generative models have recently emerged as an interesting approach to construct molecular structures atom-by-atom or fragment-by-fragment. In this study, we adopt the fragment-based strategy and decompose each input molecule into a set of small chemical fragments. In drug discovery, a few drug molecules are designed by replacing certain chemical substituents with their bioisosteres or alternative chemical moieties. This inspires us to group decomposed fragments into different fragment clusters according to their local structural environment around bond-breaking positions. In this way, an input structure can be transformed into an equivalent three-layer graph, in which individual atoms, decomposed fragments, or obtained fragment clusters act as graph nodes at each corresponding layer. We further implement a prototype model, named multi-resolution graph variational autoencoder (MRGVAE), to learn embeddings of constituted nodes at each layer in a fine-to-coarse order. Our decoder adopts a similar but conversely hierarchical structure. It first predicts the next possible fragment cluster, then samples an exact fragment structure out of the determined fragment cluster, and sequentially attaches it to the preceding chemical moiety. Our proposed approach demonstrates comparatively good performance in molecular evaluation metrics compared with several other graph-based molecular generative models. The introduction of the additional fragment cluster graph layer will hopefully increase the odds of assembling new chemical moieties absent in the original training set and enhance their structural diversity. We hope that our prototyping work will inspire more creative research to explore the possibility of incorporating different kinds of chemical domain knowledge into a similar multi-resolution neural network architecture.
(© 2023 Wiley-VCH GmbH.)

Hard carbons (HCs) are extensively investigated as the potential anodes for commercialization of sodium-ion batteries (SIBs). However, the practical deployment of HC anode suffers from the retarded Na + diffusion at the high-rate or low-temperature operation scenarios. Herein, a multiscale modification strategy by tuning HC microstructure on the particle level as well as replenishing extra Na + reservoir for the electrode through a homogeneous presodiation therapy is presented. Consequently, the coulombic efficiency of HC anode can be precisely controlled till the close-to-unit value. Detailed kinetics analysis observes that the Na + diffusivity can be drastically enhanced by two orders of magnitude at the low potential region (< 0.1 V vs. Na + /Na), which accelerates the rate-limiting step. As pairing the presodiated HC anode (≈5.0 ± 0.2 mg cm -2 ) with the NaVPO 4 F cathode (≈10.3 mg cm -2 ) in the 200 mAh pouch cell, the optimal balance of the cyclability (83% over 1000 cycles), low-temperature behavior till -40 °C as well as the maximized power output of 1500 W kg -1 can be simultaneously achieved. This synergistic modification strategy opens a new avenue to exploit the reversible, ultrafast Na + storage kinetics of HC anodes, which thus constitutes a quantum leap forward toward high-rate SIB prototyping.
(© 2023 Wiley-VCH GmbH.)

FDM (Fused Deposition Modeling) is one of the most used and industrially applied additive manufacturing processes due to its fast prototyping and manufacturing, simplicity, and low cost of the equipment. However, the mechanical properties of the printed products have a large dependence on orientation and interface strength between layers which is mainly related to the thermal union obtained. This thermal union has a large dependence on the melting and cooling down process. Additionally, the materials used must be extruded in a continuous filament before their use, which limits the materials used. However, a pellet extruder could be used directly in the printing equipment, avoiding filament extrusion. In this work, specimens of PLA (Poly(lactic acid)) with different bead orientations have been produced via filament or pellet extrusion to compare the effect of the different melting processes in the manufacturing methodology. Pellet extruded specimens showed higher infill and mechanical properties. These results were related to better adhesion between layers due to the longer melting and cooling process. The result was confirmed using DSC and XRD techniques, where a higher crystallinity was observed. A bicomponent specimen (50% pellet-50% filament) was prepared and tested, showing higher mechanical results than expected, which was, again, due to the better thermal union obtained in the pellet extruder.

Background: Design dynamics that evolve during a designer's prototyping process encapsulate important insights about the way the designer is using his or her knowledge, creativity, and reflective thinking. Nevertheless, the capturing of such dynamics is not always an easy task, as they are built through alternations between the self-first and self-third person views.
Objective: This study aimed at introducing a conceptual framework, namely 2D-ME, to provide an explainable domain that could express the dynamics across the design timeline during a prototyping process of serious games.
Methods: Within the 2D-ME framework, the Technological-Pedagogical-Content Knowledge (TPACK), its adaptation to the serious games (TPACK-Game), and the activity theory frameworks were combined to produce dynamic constructs that incorporate self-first and self-third person extension of the TPACK-Game to Games TPACK, rules, division of labor, and object. The dynamic interplay between such constructs was used as an adaptation engine within an optimization prototype process, so each sequential version of the latter could converge to the designer's initial idea of the serious game. Moreover, higher-order thinking is scaffolded with the internal Activity Interview Script proposed in this paper.
Results: An experimental case study of the application of the 2D-ME conceptual framework in the design of a light reflection game was showcased, revealing all the designer's dynamics, both from internal (via a diary) and external (via the prototype version) views. The findings of this case study exemplified the convergence of the prototyping process to an optimized output, by minimizing the mean square error between the conceptual (initial and updated) idea of the prototype, following explainable and tangible constructs within the 2D-ME framework.
Conclusions: The generic structure of the proposed 2D-ME framework allows its transferability to various levels of expertise in serious games mastering, and it is used both for the designer's process exploration and training of the novice ones.
(©Sofia Hadjileontiadou, Sofia B Dias, Leontios Hadjileontiadis. Originally published in JMIR Serious Games (https://games.jmir.org), 24.04.2023.)

Three-dimensional (3D) printing has various applications in many fields, such as soft electronics, robotic systems, biomedical implants, and the recycling of thermoplastic composite materials. Three-dimensional printing, which was only previously available for prototyping, is currently evolving into a technology that can be utilized by integrating various materials into customized structures in a single step. Owing to the aforementioned advantages, multi-functional 3D objects or multi-material-designed 3D patterns can be fabricated. In this study, we designed and fabricated 3D-printed expandable structural electronics in a substrateless auxetic pattern that can be adapted to multi-dimensional deformation. The printability and electrical conductivity of a stretchable conductor (Ag-RTV composite) were optimized by incorporating a lubricant. The Ag-RTV and RTV were printed in the form of conducting voxels and frame voxels through multi-nozzle printing and were arranged in a negative Poisson's ratio pattern with a missing rib structure, to realize an expandable passive component. In addition, the expandable structural electronics were embedded in a soft actuator via one-step printing, confirming the possibility of fabricating stable interconnections in expanding deformation via a missing rib pattern.

Solar-powered interfacial heating has emerged as a sustainable technology for hybrid applications with minimal carbon footprints. Aerogels, hydrogels, and sponges/foams are the main building blocks for state-of-the-art photothermal materials. However, these conventional three-dimensional (3D) structures and related fabrication technologies intrinsically fail to maximize important performance-enhancing strategies and this technology still faces several performance roadblocks. Herein, monolithic, self-standing, and durable aerogel matrices are developed based on composite photothermal inks and ink-extrusion 3D printing, delivering all-in-one interfacial steam generators (SGs). Rapid prototyping of multiscale hierarchical structures synergistically reduce the energy demand for evaporation, expand actual evaporation areas, generate massive environmental energy input, and improve mass flows. Under 1 sun, high water evaporation rates of 3.74 kg m -2 h -1 in calm air and 25.3 kg m -2 h -1 at a gentle breeze of 2 m s -1 are achieved, ranking among the best-performing solar-powered interfacial SGs. 3D-printed microchannels and hydrophobic modification deliver an icephobic surface of the aerogels, leading to self-propelled and rapid removal of ice droplets. This work shines light on rational fabrication of hierarchical photothermal materials, not merely breaking through the constraints of solar-powered interfacial evaporation and clean water production, but also discovering new functions for photothermal interfacial deicing.
(© 2023 Wiley-VCH GmbH.)

The Fused Filament Fabrication (FFF) method is an additive technology that is used for the creation of prototypes within Rapid Prototyping (RP) as well as for the creation of final components in piece or small-series production. The possibility of using FFF technology in the creation of final products requires knowledge of the properties of the material and, at the same time, how these properties change due to degradation effects. In this study, the mechanical properties of the selected materials (PLA, PETG, ABS, and ASA) were tested in their non-degenerate state and after exposure of the samples to the selected degradation factors. For the analysis, which was carried out by the tensile test and the Shore D hardness test, samples of normalized shape were prepared. The effects of UV radiation, high temperature environments, high humidity environments, temperature cycles, and exposure to weather conditions were monitored. The parameters obtained from the tests (tensile strength and Shore D hardness) were statistically evaluated, and the influence of degradation factors on the properties of individual materials was assessed. The results showed that even between individual manufacturers of the same filament there are differences, both in the mechanical properties and in the behavior of the material after exposure to degradation effects.

Early prevention and detection of respiratory disease have attracted extensive attention due to the significant increase in people with respiratory issues. Restraining the spread and relieving the symptom of this disease is essential. However, the traditional auscultation technique demands a high-level medical skill, and computational respiratory sound analysis approaches have limits in constrained locations. A wearable auscultation device is required to real-time monitor respiratory system health and provides consumers with ease. In this work, we developed a Respiratory Sound Diagnosis Processor Unit (RSDPU) based on Long Short-Term Memory (LSTM). The experiments and analyses were conducted on feature extraction and abnormality diagnosis algorithm of respiratory sound, and Dynamic Normalization Mapping (DNM) was proposed to better utilize quantization bits and lessen overfitting. Furthermore, we developed the hardware implementation of RSDPU including a corrector to filter diagnosis noise. We presented the FPGA prototyping verification and layout of the RSDPU for power and area evaluation. Experimental results demonstrated that RSDPU achieved an abnormality diagnosis accuracy of 81.4 %, an area of 1.57 × 1.76 mm under the SMIC 130 nm process, and power consumption of 381.8 μW, which met the requirements of high accuracy, low power consumption, and small area.
(© 2023 Walter de Gruyter GmbH, Berlin/Boston.)

Introduction: Research in the field of computational neuroscience relies on highly capable simulation platforms. With real-time capabilities surpassed for established models like the cortical microcircuit, it is time to conceive next-generation systems: neuroscience simulators providing significant acceleration, even for larger networks with natural density, biologically plausible multi-compartment models and the modeling of long-term and structural plasticity.
Methods: Stressing the need for agility to adapt to new concepts or findings in the domain of neuroscience, we have developed the neuroAIx-Framework consisting of an empirical modeling tool, a virtual prototype, and a cluster of FPGA boards. This framework is designed to support and accelerate the continuous development of such platforms driven by new insights in neuroscience.
Results: Based on design space explorations using this framework, we devised and realized an FPGA cluster consisting of 35 NetFPGA SUME boards.
Discussion: This system functions as an evaluation platform for our framework. At the same time, it resulted in a fully deterministic neuroscience simulation system surpassing the state of the art in both performance and energy efficiency. It is capable of simulating the microcircuit with 20× acceleration compared to biological real-time and achieves an energy efficiency of 48nJ per synaptic event.
Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
(Copyright © 2023 Kauth, Stadtmann, Sobhani and Gemmeke.)

Developments in polymer 3D printing (3DP) technologies have expanded their scope beyond the rapid prototyping space into other high-value markets, including the consumer sector. Processes such as fused filament fabrication (FFF) are capable of quickly producing complex, low-cost components using a wide variety of material types, such as polylactic acid (PLA). However, FFF has seen limited scalability in functional part production partly due to the difficulty of process optimization with its complex parameter space, including material type, filament characteristics, printer conditions, and "slicer" software settings. Therefore, the aim of this study is to establish a multi-step process optimization methodology-from printer calibration to "slicer" setting adjustments to post-processing-to make FFF more accessible across material types, using PLA as a case study. The results showed filament-specific deviations in optimal print conditions, where part dimensions and tensile properties varied depending on the combination of nozzle temperature, print bed conditions, infill settings, and annealing condition. By implementing the filament-specific optimization framework established in this study beyond the scope of PLA, more efficient processing of new materials will be possible for enhanced applicability of FFF in the 3DP field.

Humans, Antiviral Agents pharmacology, Antiviral Agents therapeutic use, Hepacivirus physiology, Liver Cirrhosis diagnostic imaging, Liver Cirrhosis drug therapy, Liver Cirrhosis etiology, Collagen therapeutic use, Hepatitis C, and Hepatitis C, Chronic

The novel targeted therapeutics for hepatitis C virus (HCV) in last decade solved most of the clinical needs for this disease. However, despite antiviral therapies resulting in sustained virologic response (SVR), a challenge remains where the stage of liver fibrosis in some patients remains unchanged or even worsens, with a higher risk of cirrhosis, known as the irreversible group. In this study, we provided novel tissue level collagen structural insight into early prediction of irreversible cases via image based computational analysis with a paired data cohort (of pre- and post-SVR) following direct-acting-antiviral (DAA)-based treatment. Two Photon Excitation and Second Harmonic Generation microscopy was used to image paired biopsies from 57 HCV patients and a fully automated digital collagen profiling platform was developed. In total, 41 digital image-based features were profiled where four key features were discovered to be strongly associated with fibrosis reversibility. The data was validated for prognostic value by prototyping predictive models based on two selected features: Collagen Area Ratio and Collagen Fiber Straightness. We concluded that collagen aggregation pattern and collagen thickness are strong indicators of liver fibrosis reversibility. These findings provide the potential implications of collagen structural features from DAA-based treatment and paves the way for a more comprehensive early prediction of reversibility using pre-SVR biopsy samples to enhance timely medical interventions and therapeutic strategies. Our findings on DAA-based treatment further contribute to the understanding of underline governing mechanism and knowledge base of structural morphology in which the future non-invasive prediction solution can be built upon.
(© 2023. The Author(s).)

Background: 3D-printed temporal bone models can potentially provide a cost-effective alternative to cadaver surgery that can be manufactured locally at the training department. The objective of this study was to create a cost-effective 3D-printed model suitable for mastoidectomy training using entry level and commercially available print technologies, enabling individuals, without prior experience on 3D-printing, to manufacture their own models for basic temporal bone training.
Methods: Expert technical professionals and an experienced otosurgeon identified the best material for replicating the temporal bone and created a cost-effective printing routine for the model using entry-level print technologies. Eleven participants at a temporal bone dissection course evaluated the model using a questionnaire.
Results: The 3D-printed temporal bone model was printed using a material extrusion 3D-printer with a heat resistant filament, reducing melting during drilling. After printing, a few simple post-processing steps were designed to replicate the dura, sigmoid sinus and facial nerve. Modifying the 3D-printer by installing a direct-drive and ruby nozzle resulted in more successful prints and less need for maintenance. Upon evaluation by otorhinolaryngology trainees, unanimous feedback was that the model provided a good introduction to the mastoidectomy procedure, and supplementing practice to cadaveric temporal bones.
Conclusion: In-house production of a cost-effective 3D-printed model for temporal bone training is feasible and enables training institutions to manufacture their own models. Further, this work demonstrates the feasibility of creating new temporal bone models with anatomical variation to provide ample training opportunity.
(© 2023. The Author(s).)

Objectives: The physical demands of military service place soldiers at risk of musculoskeletal injuries and are major concerns for military capability. This paper outlines the development new training technologies to prevent and manage these injuries.
Design: Narrative review.
Methods: Technologies suitable for integration into next-generation training devices were examined. We considered the capability of technologies to target tissue level mechanics, provide appropriate real-time feedback, and their useability in-the-field.
Results: Musculoskeletal tissues' health depends on their functional mechanical environment experienced in military activities, training and rehabilitation. These environments result from the interactions between tissue motion, loading, biology, and morphology. Maintaining health of and/or repairing joint tissues requires targeting the "ideal" in vivo tissue mechanics (i.e., loading and strain), which may be enabled by real-time biofeedback. Recent research has shown that these biofeedback technologies are possible by integrating a patient's personalised digital twin and wireless wearable devices. Personalised digital twins are personalised neuromusculoskeletal rigid body and finite element models that work in real-time by code optimisation and artificial intelligence. Model personalisation is crucial in obtaining physically and physiologically valid predictions.
Conclusions: Recent work has shown that laboratory-quality biomechanical measurements and modelling can be performed outside the laboratory with a small number of wearable sensors or computer vision methods. The next stage is to combine these technologies into well-designed easy to use products.
Competing Interests: Declaration of interest statement All authors disclose that they have no interests to declare with other people or organisations that could inappropriately influence this work. Furthermore, all co-authors have agreed by email to be co-authors on the manuscript.
(Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Additive manufacturing has revolutionized prototyping and small-scale production in the past years. By creating parts layer by layer, a tool-less production technology is established, which allows for rapid adaption of the manufacturing process and customization of the product. However, the geometric freedom of the technologies comes with a large number of process parameters, especially in Fused Deposition Modeling (FDM), all of which influence the resulting part's properties. Since those parameters show interdependencies and non-linearities, choosing a suitable set to create the desired part properties is not trivial. This study demonstrates the use of Invertible Neural Networks (INN) for generating process parameters objectively. By specifying the desired part in the categories of mechanical properties, optical properties and manufacturing time, the demonstrated INN generates process parameters capable of closely replicating the desired part. Validation trials prove the precision of the solution with measured properties achieving the desired properties to up to 99.96% and a mean accuracy of 85.34%.

Animals, Rats, Electrochemical Techniques methods, Hydrogen Peroxide, Peroxidase, Peroxidases, Microfluidics, and Nanostructures

We present a novel electrochemical microfluidic device for the sensitive and selective detection of hydrogen peroxide (H 2 O 2 ) through a VO 2 nanostructure enzyme mimic. The low-cost ($0.50) microfluidic chip was fabricated using a simple and rapid prototyping technique via three syringe needles. Each needle played the role of an electrode (working, reference, and counter), and was connected by micro-hoses to a construction of the electrochemical microfluidic chip. The colloidal VO 2 nanoflakes with peroxidase-like activity could be easily transferred on to the electrodes by a syringe, for development of a novel electrochemical platform to enable the detection of H 2 O 2 . The unique microfluidic electrochemical sensor delivered a wide linear dynamic range from 0.5 to 300 μM, with a limit of detection of 0.14 μM. The facile, rapid, sensitive, and selective as-fabricated H 2 O 2 sensors were proven to be appropriate for the real-time monitoring of H 2 O 2 released from PC12 cells. The integration of a microfluidic sensor with an enzyme mimic nanostructure is essentially a promising strategy for the low-cost and accurate monitoring of physiological processes.

Fused Filament Fabrication (FFF) 3D printing is an additive technology used to manufacture parts. Used in the engineering industry for prototyping polymetric parts, this disruptive technology has been adopted commercially and there are affordable printers on the market that allow for at-home printing. This paper examines six methods of reducing the energy and material consumption of 3D printing. Using different commercial printers, each approach was investigated experimentally, and the potential savings were quantified. The modification most effective at reducing energy consumption was the hot-end insulation, with savings of 33.8-30.63%, followed by the sealed enclosure, yielding an average power reduction of 18%. For material, the most influential change was noted using 'lightning infill', reducing material consumption by 51%. The methodology includes a combined energy- and material-saving approach in the production of a referenceable 'Utah Teapot' sample object. Using combined techniques on the Utah Teapot print, the material consumption was reduced by values between 55.8% and 56.4%, and power consumption was reduced by 29% to 38%. The implementation of a data-logging system allowed us to identify significant thermal management and material usage opportunities to minimise power consumption, providing solutions for a more positive impact on the sustainable manufacturing of 3D printed parts.

Background: Parents often use baby walkers (BWs) as assistive devices to improve their infants' independent movement and motor skill acquisition. However, the literature suggests that conventional baby walkers (CBW) may cause delays in an infant's ability to walk independently and musculoskeletal burden on parents.
Objective: In the current study, a baby walker (RBW) with chest support was redesigned and ergonomically assessed during an infant-walking task.
Methods: The anthropometric dimensions of 90 infants aged 7-11 months were measured in the city of Urmia, northwestern Iran. Following redesigning based on the results from expert panel meetings and prototyping of the RBW, 18 mothers (age: 28.33±4.27 and height: 163.75±5.32 and weight: 59.45±5.99) with their infants (9 boys and 9 girls) performed a simulated infant walking task in two experimental sessions using the CBW and RBW over a repeated measurements design. The infants' feet track patterns, including the number of steps and step distances were assessed via the image analysis of the footprints. The mothers' body posture and lower back spinal load were evaluated using Rapid Upper Limb Assessment (RULA) technique and 3D Static Strength Prediction Program (3DSSPP), respectively.
Results: Wilcoxon signed-rank tests showed infants walked more steps with the RBW (p = 0.002). Similarly, the distance between the infants' left heel strike (p = 0.008) and their right and left toe-off (p = 0.03 and 0.02 respectively) was also significantly lower in the RBW use. Additionally, the body posture of mothers was improved (RULA final score from 7 for CBW to 5 for RBW). Moreover, lower back compression and shear forces were reduced significantly (p = 0.002) by the RBW use.
Conclusion: According to the feet track pattern, infants took more balanced steps when the RBW was used. In addition, mothers were subjected to less pressure on the lumbar region when they placed and lifted their infant from the RBW. However, further work is necessary to investigate potential long-term effects of the RBWs use.

Today, additive manufacturing (AM) is considered one of the vital tenets of the industry 4.0 revolution due to its high productivity, decentralized production and rapid prototyping. This work aims to study the mechanical and structural properties of polyhydroxybutyrate as an additive in blend materials and its potential in medical applications. PHB/PUA blend resins were formulated with 0 wt.%, 6 wt.%, 12 wt.% and 18 wt.% of PHB concentration. Stereolithography or an SLA 3D printing technique were used to evaluate the printability of the PHB/PUA blend resins. Additionally, from FESEM analysis, a change was observed in PUA's microstructure, with an additional number of voids spotted. Furthermore, from XRD analysis, as PHB concentration increased, the crystallinity index (CI) also increased. This indicates the brittleness properties of the materials, which correlated to the weak performance of the tensile and impact properties. Next, the effect of PHB loading concentration within PHB/PUA blends and aging duration towards the mechanical performance of tensile and impact properties was also studied by using analysis of variance (ANOVA) with a two-way method. Finally, 12 wt.% of PHB/PUA was selected to 3D print the finger splint due to its characteristics, which are compatible to be used in finger bone fracture recovery.

Humans, Magnetic Resonance Imaging, Image Processing, Computer-Assisted, and Triple Negative Breast Neoplasms pathology

Co-clinical trials are the concurrent or sequential evaluation of therapeutics in both patients clinically and patient-derived xenografts (PDX) pre-clinically, in a manner designed to match the pharmacokinetics and pharmacodynamics of the agent(s) used. The primary goal is to determine the degree to which PDX cohort responses recapitulate patient cohort responses at the phenotypic and molecular levels, such that pre-clinical and clinical trials can inform one another. A major issue is how to manage, integrate, and analyze the abundance of data generated across both spatial and temporal scales, as well as across species. To address this issue, we are developing MIRACCL (molecular and imaging response analysis of co-clinical trials), a web-based analytical tool. For prototyping, we simulated data for a co-clinical trial in "triple-negative" breast cancer (TNBC) by pairing pre- (T0) and on-treatment (T1) magnetic resonance imaging (MRI) from the I-SPY2 trial, as well as PDX-based T0 and T1 MRI. Baseline (T0) and on-treatment (T1) RNA expression data were also simulated for TNBC and PDX. Image features derived from both datasets were cross-referenced to omic data to evaluate MIRACCL functionality for correlating and displaying MRI-based changes in tumor size, vascularity, and cellularity with changes in mRNA expression as a function of treatment.

With the development of material science, additive manufacturing technology has been employed for pelvic surgery, addressing the challenges, such as the complex structure of the pelvis, difficulty in exposing the operative area, and poor visibility, of the traditional pelvic surgery. However, only limited studies have been done to review the research hotspots and trends of the additive manufacturing technology applied for pelvic surgery. In this study, we comprehensively analyzed the literatures related to additive manufacturing technology in pelvic surgery by a bibliometrics analysis and found that additive manufacturing technology is widely used in several aspects of preoperative diagnosis, preoperative planning, intraoperative navigation, and personalized implants for pelvic surgery. Firstly, we searched and screened 856 publications from the Web of Science Core Collection (WoSCC) with TS = (3D printing OR 3D printed OR three-dimensional printing OR additive manufacturing OR rapid prototyping) AND TS = (pelvis OR sacrum OR ilium OR pubis OR ischium OR ischia OR acetabulum OR hip) as the search strategy. Then, 565 of these were eliminated by evaluating the titles and abstracts, leaving 291 pieces of research literature whose relevant information was visually displayed using VOSviewer. Furthermore, 10 publications with high citations were selected by reading all publications extensively for carefully evaluating their Titles, Purposes, Results, Limitations, Journal of affiliation, and Citations. Our results of bibliometric analysis demonstrated that additive manufacturing technology is increasingly applied in pelvic surgery, providing readers with a valuable reference for fully comprehending the research hotspots and trends in the application of additive manufacturing technology in pelvic surgery.
Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
(Copyright © 2023 Li, Wang, Lv, Bai, Meng, Li and Wu.)

This paper describes some insights on applicability of a Selective Laser Melting and Direct Metal Laser Sintering technology-manufactured turbine blade models for aerodynamic tests in a wind tunnel. The principal idea behind this research was to assess the possibilities of using 'raw' DLMS printed turbine blade models for gas-flow experiments. The actual blade, manufactured using the DLMS technology, is assessed in terms of surface quality (roughness), geometrical shape and size (outline), quality of counterbores and quality of small diameter holes. The results are evaluated for the experimental aerodynamics standpoint. This field of application imposes requirements that have not yet been described in the literature. The experimental outcomes prove the surface quality does not suffice to conduct quantitative experiments. The holes that are necessary for pressure measurements in wind tunnel experiments cannot be reduced below 1 mm in diameter. The dimensional discrepancies are on the level beyond acceptable. Additionally, the problem of 'reversed tolerance', with the material building up and distorting the design, is visible in elements printed with the DLMS technology. The results indicate the necessity of post-machining of the printed elements prior their experimental usage, as their features in the 'as fabricated' state significantly disturb the flow conditions.

Natural fibers or their derivatives have gained significant attention as green fillers or reinforcement materials due to their abundant availability, environment-friendly nature and biodegradability for sustainable development. Despite the availability of modern alternatives such as concrete, glass-fiber/resin composites, steel, and plastics, there is still considerable demand for naturally occurring based materials for different applications due to their low cost, durability, strength, heat, sound, and fire-resistance characteristics. 3D printing has provided a novel approach to the development and advancement of natural fiber-based composite materials, as well as an important platform for the advancement of biomass materials toward intelligentization and industrialization. The features of 3D printing, particularly fast prototyping and small start-up, allow the easy fabrication of materials for a wide range of applications. This review highlights the current progress and potential commercial applications of 3D printed composites reinforced with natural fibers or biomass. This study discussed that 3D printing technology can be effectively utilized for different applications, including producing electroactive papers, fuel cell membranes, adhesives, wastewater treatment, biosensors, and its potential applications in the automobile, building, and construction industries. The research in the literature showed that even if the field of 3D printing has advanced significantly, problems still need to be solved, such as material incompatibility and material cost. Further studies could be conducted to improve and adapt the methods to work with various materials. More effort should be put into developing affordable printer technologies and materials that work with these printers to broaden the applications for 3D printed objects.
Competing Interests: The authors declare no conflict of interest.The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(© 2023 The Author(s).)

Humans, Printing, Three-Dimensional, Computer-Aided Design, Eye, Ophthalmology, and Bioprinting

Three-dimensional printing (3DP) technology is a rapid prototyping technology that is widely used in the medical field. It can be combined with computer-aided design, material manufacturing, and other technologies to construct medical-related appliances, human implants and even cell-based models or biological tissues. In the field of ophthalmology, the technology can be used to manufacture ocular anatomical models, glasses, intraocular implants, microsurgical instruments, drugs, etc. It can also enable future 'bioprinting', involving the refractive and nervous systems of the eyeball, with excellent development prospects in the field. This review introduces the development of 3DP technology in ophthalmology and discusses its application and potential.
(© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Printing, Three-Dimensional, Hydrogen Peroxide, and Luminescence

Low force stereolithography is exploited for the first time for one-step facile fabrication of chemiluminescence (CL) flow-through cells that bear unrivalled features as compared to those available through milling or blowing procedures or alternative 3D printing technologies. A variety of bespoke cross-section geometries with polyhedral features (namely, triangular, square, and five-side polygon) as well as semicircular cross-section are herein critically evaluated in terms of analytical performance against the standardcircular cross-section in a flat spirally-shape format. The idea behind is to maximize capture of elicited light by the new designs while leveraging 3D printing further for fabrication of (i) customized gaskets that enable reliable attaching of the active mixing zone of the CL cell to the detection window, (ii) in-line 3D-printed serpentine reactors, and (iii) flow confluences with tailorable shapes for enhancing mixing of samples with CL reagents. Up to twenty transparent functional cells were simultaneously fabricated without inner supports following post-curing and surface treatment protocols lasting less than 5 h. In fact, previous attempts to print spirally-shaped cells in one-step by resorting to less cost effective photopolymer inkjet printing technologies were unsuccessful because of the requirement of lengthy procedures (>15 days) for quantitative removal of the support material. By exploiting the phthalazinedione-hydrogen peroxide chemistry as a model reaction, the five-side irregular pentagon cell exhibited superior analytical figures of merit in terms of LOD, dynamic range and intermediate precision as compared to alternative designs. Computational fluid dynamic simulations for mapping velocities at the entry region of the spiral cell corroborated the fact that the 5-side polygon cross-section flow-cell with Y-type confluence permitted the most efficient mixing of reagents and sample while enabling larger flow velocities near the inlet that contribute to a more efficient capture of the photons from the flash-type reaction. The applicability of the 3D-printed 5-side polygon CL cell for automatic determination of hydrogen peroxide using a computerized hybrid flow system was demonstrated for the analysis of high matrix samples, viz., seawater and saliva, with relative recoveries ranging from 83 to 103%.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2023 Elsevier B.V. All rights reserved.)

Humans, Organs at Risk, Image Processing, Computer-Assisted methods, and Tomography, X-Ray Computed methods

Background and Objective: Despite fast evolution cycles in deep learning methodologies for medical imaging in radiotherapy, auto-segmentation solutions rarely run in clinics due to the lack of open-source frameworks feasible for processing DICOM RT Structure Sets. Besides this shortage, available open-source DICOM RT Structure Set converters rely exclusively on 2D reconstruction approaches leading to pixelated contours with potentially low acceptance by healthcare professionals. PyRaDiSe, an open-source, deep learning framework independent Python package, addresses these issues by providing a framework for building auto-segmentation solutions feasible to operate directly on DICOM data. In addition, PyRaDiSe provides profound DICOM RT Structure Set conversion and processing capabilities; thus, it applies also to auto-segmentation-related tasks, such as dataset construction for deep learning model training.
Methods: The PyRaDiSe package follows a holistic approach and provides DICOM data handling, deep learning model inference, pre-processing, and post-processing functionalities. The DICOM data handling allows for highly automated and flexible handling of DICOM image series, DICOM RT Structure Sets, and DICOM registrations, including 2D-based and 3D-based conversion from and to DICOM RT Structure Sets. For deep learning model inference, extending given skeleton classes is straightforwardly achieved, allowing for employing any deep learning framework. Furthermore, a profound set of pre-processing and post-processing routines is included that incorporate partial invertibility for restoring spatial properties, such as image origin or orientation.
Results: The PyRaDiSe package, characterized by its flexibility and automated routines, allows for fast deployment and prototyping, reducing efforts for auto-segmentation pipeline implementation. Furthermore, while deep learning model inference is independent of the deep learning framework, it can easily be integrated into famous deep learning frameworks such as PyTorch or Tensorflow. The developed package has successfully demonstrated its capabilities in a research project at our institution for organs-at-risk segmentation in brain tumor patients. Furthermore, PyRaDiSe has shown its conversion performance for dataset construction.
Conclusions: The PyRaDiSe package closes the gap between data science and clinical radiotherapy by enabling deep learning segmentation models to be easily transferred into clinical research practice. PyRaDiSe is available on https://github.com/ubern-mia/pyradise and can be installed directly from the Python Package Index using pip install pyradise.
Competing Interests: Declaration of Competing Interest Authors declare that they have no conflict of interest.
(Copyright © 2023 The Author(s). Published by Elsevier B.V. All rights reserved.)

Humans, Medication Systems, Hospital, Patient Safety, Medication Therapy Management, and Medical Order Entry Systems

Introduction: Poorly designed electronic medication management systems (EMMS) or computerized physician order entry (CPOE) systems in hospital settings can result in usability issues and in turn, patient safety risks. As a safety science, human factors and safety analysis methods have potential to support the safe and usable design of EMMS.
Objective: To identify and describe human factors and safety analysis methods that have been used in the design or redesign of EMMS used in hospital settings.
Materials and Methods: A systematic review, following PRISMA guidelines, was conducted by searching online databases and relevant journals from January 2011 to May 2022. Studies were included if they described the practical application of human factors and safety analysis methods to support the design or redesign of a clinician-facing EMMS, or its components. Methods used were extracted and mapped to human centered design (HCD) activities: understanding context of use; specifying user requirements; producing design solutions; and evaluating the design.
Results: Twenty-one papers met the inclusion criteria. Overall, 21 human factors and safety analysis methods were used in the design or redesign of EMMS with prototyping, usability testing, participant surveys/questionnaires and interviews the most frequent. Human factors and safety analysis methods were most frequently used to evaluate the design of a system (n = 67; 56.3%). Nineteen of 21 (90%) methods used aimed to identify usability issues and/or support iterative design; only one paper utilized a safety-oriented method and one, a mental workload assessment method.
Discussion and Conclusion: While the review identified 21 methods, EMMS design primarily utilized a subset of available methods, and rarely a method focused on safety. Given the high-risk nature of medication management in complex hospital environments, and the potential for harm due to poorly designed EMMS, there is significant potential to apply more safety-oriented human factors and safety analysis methods to support EMMS design.
Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2023 The Author(s). Published by Elsevier B.V. All rights reserved.)

Green Fluorescent Proteins chemistry, Green Fluorescent Proteins genetics, Biosynthetic Pathways, Metabolic Engineering methods, Nicotinamide Mononucleotide biosynthesis, Enzymes chemistry, and Enzymes genetics

Engineering biological systems to test new pathway variants containing different enzyme homologs is laborious and time-consuming. To tackle this challenge, a strategy was developed for rapidly prototyping enzyme homologs by combining cell-free protein synthesis (CFPS) with split green fluorescent protein (GFP). This strategy featured two main advantages: (1) dozens of enzyme homologs were parallelly produced by CFPS within hours, and (2) the expression level and activity of each homolog was determined simultaneously by using the split GFP assay. As a model, this strategy was applied to optimize a 3-step pathway for nicotinamide mononucleotide (NMN) synthesis. Ten enzyme homologs from different organisms were selected for each step. Here, the most productive homolog of each step was identified within 24 h rather than weeks or months. Finally, the titer of NMN was increased to 1213 mg/L by improving physiochemical conditions, tuning enzyme ratios and cofactor concentrations, and decreasing the feedback inhibition, which was a more than 12-fold improvement over the initial setup. This strategy would provide a promising way to accelerate design-build-test cycles for metabolic engineering to improve the production of desired products.
(© 2023 Wiley Periodicals LLC.)

Brain diagnostic imaging, Algorithms, Image Processing, Computer-Assisted methods, Magnetic Resonance Imaging methods, and Software

Purpose: Introduce Shimming Toolbox ( https://shimming-toolbox.org), an open-source software package for prototyping new methods and performing static, dynamic, and real-time B0 shimming as well as B1 shimming experiments.
Methods: Shimming Toolbox features various field mapping techniques, manual and automatic masking for the brain and spinal cord, B0 and B1 shimming capabilities accessible through a user-friendly graphical user interface. Validation of Shimming Toolbox was demonstrated in three scenarios: (i) B0 dynamic shimming in the brain at 7T using custom AC/DC coils, (ii) B0 real-time shimming in the spinal cord at 3T, and (iii) B1 static shimming in the spinal cord at 7T.
Results: The B0 dynamic shimming of the brain at 7T took about 10 min to perform. It showed a 47% reduction in the standard deviation of the B0 field, associated with noticeable improvements in geometric distortions in EPI images. Real-time dynamic xyz-shimming in the spinal cord took about 5 min and showed a 30% reduction in the standard deviation of the signal distribution. B1 static shimming experiments in the spinal cord took about 10 min to perform and showed a 40% reduction in the coefficient of variation of the B1 field.
Conclusion: Shimming Toolbox provides an open-source platform where researchers can collaborate, prototype and conveniently test B0 and B1 shimming experiments. Future versions will include additional field map preprocessing techniques, optimization algorithms, and compatibility across multiple MRI manufacturers.
(© 2022 International Society for Magnetic Resonance in Medicine.)

Engineering design is traditionally performed by hand: an expert makes design proposals based on past experience, and these proposals are then tested for compliance with certain target specifications. Testing for compliance is performed first by computer simulation using what is called a discipline model. Such a model can be implemented by finite element analysis, multibody systems approach, etc. Designs passing this simulation are then considered for physical prototyping. The overall process may take months and is a significant cost in practice. We have developed a Bayesian optimization (BO) system for partially automating this process by directly optimizing compliance with the target specification with respect to the design parameters. The proposed method is a general framework for computing the generalized inverse of a high-dimensional nonlinear function that does not require, for example, gradient information, which is often unavailable from discipline models. We furthermore develop a three-tier convergence criterion based on: 1) convergence to a solution optimally satisfying all specified design criteria; 2) detection that a design satisfying all criteria is infeasible; or 3) convergence to a probably approximately correct (PAC) solution. We demonstrate the proposed approach on benchmark functions and a vehicle chassis design problem motivated by an industry setting using a state-of-the-art commercial discipline model. We show that the proposed approach is general, scalable, and efficient and that the novel convergence criteria can be implemented straightforwardly based on the existing concepts and subroutines in popular BO software packages.

Child, Humans, Magnets, Prosthesis Design, Pulsatile Flow, Magnetics, Equipment Design, Heart-Assist Devices, and Heart, Artificial

Background: The purpose of this research is to address ongoing device shortfalls for pediatric patients by developing a novel pediatric hybrid total artificial heart (TAH). The valveless magnetically-levitated MCS device (Dragon Heart) has only two moving parts, integrates an axial and centrifugal blood pump into a single device, and will occupy a compact footprint within the chest for the pediatric patient population.
Methods: Prior work on the Dragon Heart focused on the development of pump designs to achieve hemodynamic requirements. The impeller of these pumps was shaft-driven and thus could not be integrated for testing. The presented research leverages an existing magnetically levitated axial flow pump and focuses on centrifugal pump development. Using the axial pump diameter as a geometric constraint, a shaftless, magnetically supported centrifugal pump was designed for placement circumferentially around the axial pump domain. The new design process included the computational analysis of more than 50 potential centrifugal impeller geometries. The resulting centrifugal pump designs were prototyped and tested for levitation and no-load rotation, followed by in vitro testing using a blood analog. To meet physiologic demands, target performance goals were pressure rises exceeding 90 mm Hg for flow rates of 1-5 L/min with operating speeds of less than 5000 RPM.
Results: Three puck-shaped, channel impellers for the centrifugal blood pump were selected based on achieving performance and space requirements for magnetic integration. A quasi-steady flow analysis revealed that the impeller rotational position led to a pulsatile component in the pressure generation. After prototyping, the centrifugal prototypes (3, 4, and 5 channeled designs) demonstrated levitation and no-load rotation. Hydraulic experiments established pressure generation capabilities beyond target requirements. The pressure-flow performance of the prototypes followed expected trends with a dependence on rotational speed. Pulsatile blood flow was observed without pump-speed modulation due to rotating channel passage frequency.
Conclusion: The results are promising in the advancement of this pediatric TAH. The channeled impeller design creates pressure-flow curves that are decoupled from the flow rate, a benefit that could reduce the required controller inputs and improve treatment of hypertensive patients.
(© 2022 International Center for Artificial Organs and Transplantation and Wiley Periodicals LLC.)

Lab-On-A-Chip Devices, Polymers, Dimethylpolysiloxanes, and Microtechnology

Polydimethylsiloxane (PDMS) based microfluidic devices have found increasing utility for electrophoretic and electrokinetic assays because of their ease of fabrication using replica molding. However, the fabrication of high-resolution molds for replica molding still requires the resource-intensive and time-consuming photolithography process, which precludes quick design iterations and device optimization. We here demonstrate a low-cost, rapid microfabrication process, based on electrohydrodynamic jet printing (EJP), for fabricating non-sacrificial master molds for replica molding of PDMS microfluidic devices. The method is based on the precise deposition of an electrically stretched polymeric solution of polycaprolactone in acetic acid on a silicon wafer placed on a computer-controlled motion stage. This process offers the high-resolution (order 10  μ $\umu$ m) capability of photolithography and rapid prototyping capability of inkjet printing to print high-resolution templates for elastomeric microfluidic devices within a few minutes. Through proper selection of the operating parameters such as solution flow rate, applied electric field, and stage speed, we demonstrate microfabrication of intricate master molds and corresponding PDMS microfluidic devices for electrokinetic applications. We demonstrate the utility of the fabricated PDMS microchips for nonlinear electrokinetic processes such as electrokinetic instability and controlled sample splitting in ITP. The ability to rapid prototype customized reusable master molds with order 10  μ $\umu$ m resolution within a few minutes can help in designing and optimizing microfluidic devices for various electrokinetic applications.
(© 2023 Wiley-VCH GmbH.)

Humans, Denture, Complete, Printing, Three-Dimensional, Research Design, Dental Materials, Denture Bases, Computer-Aided Design, and Mouth, Edentulous

Purpose: This study compared the dimensional changes between computer-aided design and computer-aided manufacturing (CAD-CAM) milled complete denture bases (CDBs) and three-dimensional (3D) printed CDBs.
Materials and Methods: One maxillary completely edentulous stone model was fabricated with three reference points at the incisive papilla, right molar, and left molar areas marked as X, Y, and Z, respectively. It was scanned to produce a standard tessellation language (STL) file, which was imported to a metal milling machine software to produce the metal model. This metal model was used to fabricate 30 CDBs for analysis. The CDBs were divided into three groups (n = 10 each) according to the fabrication method used as follows: Group 1, CAD-CAM milled CDBs; Group 2, 3D printed CDBs; and Group 3, conventional compression molded CDBs. The CDBs of all groups were scanned after fabrication, and the dimensional changes in each were evaluated by two methods. The first was the two-dimensional evaluation method that involved linear measurement of the distances between the reference points (X-Y, X-Z, and Y-Z) of the scanned reference cast and dentures. The second method was the 3D evaluation method that involved the superimposition of the STL files of the dentures on the STL file of the reference cast. Data were calculated and were statistically analyzed using one-way analysis of variance and Tukey's pairwise post hoc tests.
Results: There was a significant difference in the dimensional accuracy between the CAD-CAM milled, 3D printed, and conventional compression molded CDBs (p < 0.05).
Conclusion: The dimensional accuracy of the CAD-CAM milling system in complete denture fabrication is superior to that of the compression molding and 3D printing systems.
(© 2022 by the American College of Prosthodontists.)

Humans, Research Design, and Feeding and Eating Disorders

Purpose of Review: Digital (i.e., online, mobile) interventions have potential to increase access to care for people with eating disorders, but engagement with digital interventions has been challenging. Human-centered design is a methodology that centralizes the design of technologies on the people who will be using them and the settings in which they will be implemented, to yield solutions with high engagement and clinical impact. The paper presents an overview of the human-centered design process, followed by a review of publications that have applied design methods to digital interventions for eating disorders.
Recent Findings: Design research has been conducted via needs assessments, prototyping and usability studies, and during ongoing delivery of digital eating disorder interventions. There has been growing research applying design methods to digital interventions for eating disorders. Additional opportunities include designing for implementation, designing for equity, and designing for the optimization of digital interventions over time.
(© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Because they are made of elastically deformable and compliant materials, soft robots can passively change shape and conform to their environment, providing potential advantages over traditional robotics approaches. However, existing manufacturing workflows are often labor intensive and limited in their ability to create highly integrated three-dimensional (3D) heterogeneous material systems. In this study, we address this with a streamlined workflow to produce field-deployable soft robots based on 3D printing with digital light processing (DLP) of silicone-like soft materials. DLP-based 3D printing is used to create soft actuators (2.2 g) capable of exerting up to 0.5 Newtons of force that are integrated into a bioinspired untethered soft robot. The robot walks underwater at speeds comparable with its biological analog, the brittle star. Using a model-free planning algorithm and feedback, the robot follows remote commands to move to desired positions. Moreover, we show that the robot is able to perform untethered locomotion outside of a laboratory and in a natural aquatic environment. Our results represent progress in soft robot manufacturing autonomy for a 3D printed untethered soft robot.

The concept of personalized medicine and overcoming healthcare inequalities have become extremely popular in recent decades. Polymers can support cost reductions, the simplicity of customized printing processes, and possible future wide-scale expansion. Polymers with β-tricalcium phosphate (TCP) are well known for their synergy with oral tissues and their ability to induce osteoconductivity. However, poor information exists concerning their properties after the printing process and whether they can maintain an unaffected biological role. Poly(ε-caprolactone) (PCL) polymer and PCL compounded with TCP 20% composite were printed with a Prusa Mini-LCD- ® 3D printer. Samples were sterilised by immersion in a 2% peracetic acid solution. Sample analyses were performed using infrared-spectroscopy and statical mechanical tests. Biocompatibility tests, such as cell adhesion on the substrate, evaluations of the metabolic activity of viable cells on substrates, and F-actin labelling, followed by FilaQuant-Software were performed using a MC3T3-E1 pre-osteoblasts line. PCL+β-TCP-20% composite is satisfactory for commercial 3D printing and appears suitable to sustain an ISO14937:200937 sterilization procedure. In addition, the proper actin cytoskeleton rearrangement clearly shows their biocompatibility as well as their ability to favour osteoblast adhesion, which is a pivotal condition for cell proliferation and differentiation.

Cell-free protein synthesis (CFPS) is a method utilized for producing proteins without the limits of cell viability. The plug-and-play utility of CFPS is a key advantage over traditional plasmid-based expression systems and is foundational to the potential of this biotechnology. A key limitation of CFPS is the varying stability of DNA types, limiting the effectiveness of cell-free protein synthesis reactions. Researchers generally rely on plasmid DNA for its ability to support robust protein expression in vitro . However, the overhead required to clone, propagate, and purify plasmids reduces the potential of CFPS for rapid prototyping. While linear templates overcome the limits of plasmid DNA preparation, linear expression templates (LETs) were under-utilized due to their rapid degradation in extract based CFPS systems, limiting protein synthesis. To reach the potential of CFPS using LETs, researchers have made notable progress toward protection and stabilization of linear templates throughout the reaction. The current advancements range from modular solutions, such as supplementing nuclease inhibitors and genome engineering to produce strains lacking nuclease activity. Effective application of LET protection techniques improves expression yields of target proteins to match that of plasmid-based expression. The outcome of LET utilization in CFPS is rapid design-build-test-learn cycles to support synthetic biology applications. This review describes the various protection mechanisms for linear expression templates, methodological insights for implementation, and proposals for continued efforts that may further advance the field.

Humans, Child, Electromyography, Upper Extremity physiology, Printing, Three-Dimensional, Exoskeleton Device, and Motor Disorders

The rehabilitation of children with motor disorders is mainly focused on physical interventions. Numerous studies have demonstrated the benefits of upper function using robotic exoskeletons. However, there is still a gap between research and clinical practice, owing to the cost and complexity of these devices. This study presents a proof of concept of a 3D-printed exoskeleton for the upper limb, following a design that replicates the main characteristics of other effective exoskeletons described in the literature. 3D printing enables rapid prototyping, low cost, and easy adjustment to the patient anthropometry. The 3D-printed exoskeleton, called POWERUP, assists the user's movement by reducing the effect of gravity, thereby allowing them to perform upper limb exercises. To validate the design, this study performed an electromyography-based assessment of the assistive performance of POWERUP, focusing on the muscular response of both the biceps and triceps during elbow flexion-extension movements in 11 healthy children. The Muscle Activity Distribution (MAD) is the proposed metric for the assessment. The results show that (1) the exoskeleton correctly assists elbow flexion, and (2) the proposed metric easily identifies the exoskeleton configuration: statistically significant differences ( p -value = 2.26 ⋅ 10 -7 < 0.001) and a large effect size (Cohen's d = 3.78 > 0.8) in the mean MAD value were identified for both the biceps and triceps when comparing the transparent mode (no assistance provided) with the assistive mode (anti-gravity effect). Therefore, this metric was proposed as a method for assessing the assistive performance of exoskeletons. Further research is required to determine its usefulness for both the evaluation of selective motor control (SMC) and the impact of robot-assisted therapies.
Competing Interests: The authors declare there are no competing interests.
(©2023 Sanchez et al.)

Differentiable programming has facilitated numerous methodological advances in scientific computing. Physics engines supporting automatic differentiation have simpler code, accelerating the development process and reducing the maintenance burden. Furthermore, fully differentiable simulation tools enable direct evaluation of challenging derivatives-including those directly related to properties measurable by experiment-that are conventionally computed with finite difference methods. Here, we investigate automatic differentiation in the context of orbital-free density functional theory (OFDFT) simulations of materials, introducing PROFESS-AD. Its automatic evaluation of properties derived from first derivatives, including functional potentials, forces, and stresses, facilitates the development and testing of new density functionals, while its direct evaluation of properties requiring higher-order derivatives, such as bulk moduli, elastic constants, and force constants, offers more concise implementations than conventional finite difference methods. For these reasons, PROFESS-AD serves as an excellent prototyping tool and provides new opportunities for OFDFT.

Magnetic-stimuli responsive hydrogels are quickly becoming a promising class of materials across numerous fields, including biomedical devices, soft robotic actuators, and wearable electronics. Hydrogels are commonly fabricated by conventional methods that limit the potential for complex architectures normally required for rapidly changing custom configurations. Rapid prototyping using 3D printing provides a solution for this. Previous work has shown successful extrusion 3D printing of magnetic hydrogels; however, extrusion-based printing is limited by nozzle resolution and ink viscosity. VAT photopolymerization offers a higher control over resolution and build-architecture. Liquid photo-resins with magnetic nanocomposites normally suffer from nanoparticle agglomeration due to local magnetic fields. In this work, we develop an optimised method for homogenously infusing up to 2 wt % superparamagnetic iron oxide nanoparticles (SPIONs) with a 10 nm diameter into a photo-resin composed of water, acrylamide and PEGDA, with improved nanoparticle homogeneity and reduced agglomeration during printing. The 3D printed starfish hydrogels exhibited high mechanical stability and robust mechanical properties with a maximum Youngs modulus of 1.8 MPa and limited shape deformation of 10% when swollen. Each individual arm of the starfish could be magnetically actuated when a remote magnetic field is applied. The starfish could grab onto a magnet with all arms when a central magnetic field was applied. Ultimately, these hydrogels retained their shape post-printing and returned to their original formation once the magnetic field had been removed. These hydrogels can be used across a wide range of applications, including soft robotics and magnetically stimulated actuators.
Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. The authors declare the following financial interests/personal relationships which may be considered as potential competing interests.
(©2023PublishedbyElsevierLtd.)

There has been a compelling demand of fabricating high-resolution complex three-dimensional (3D) structures in nanotechnology. While two-photon lithography (TPL) largely satisfies the need since its introduction, its low writing speed and high cost make it impractical for many large-scale applications. We report a digital holography-based TPL platform that realizes parallel printing with up to 2000 individually programmable laser foci to fabricate complex 3D structures with 90 nm resolution. This effectively improves the fabrication rate to 2,000,000 voxels/sec. The promising result is enabled by the polymerization kinetics under a low-repetition-rate regenerative laser amplifier, where the smallest features are defined via a single laser pulse at 1 kHz. We have fabricated large-scale metastructures and optical devices of up to centimeter-scale to validate the predicted writing speed, resolution, and cost. The results confirm our method provides an effective solution for scaling up TPL for applications beyond laboratory prototyping.
(© 2023. The Author(s).)

Background: Botswana, like most sub-Sahara African nations, uses conventional orthopaedic implants that are sourced from major manufactures in the West. The implants are mass-produced and designed with universal configurations to fit an average patient. During surgery, surgeons thus sometimes bend the implants to match the individual bone anatomy, especially for paediatric patients and those with unique deformities, thus risking implant failure. The purpose of this project was to show the feasibility of developing safe and effective patient-specific orthopaedic implants in a low-resourced market.
Methods: CT Scan slice files of a paediatric patient with Ollier's disease were used to reconstruct the lower limb anatomy. The resultant files were 3D printed into prototypes that showed severe right knee valgus deformity. The surgeon used the prototype to plan for corrective femoral osteotomy and the required implant. The implant design and planned surgery were subsequently simulated on the Medical Design Studio software for proper fitting before final implant printing. Surgery was then performed, followed by 12 weeks of physiotherapy.
Results: Post-surgical x-rays demonstrated good implant positioning and knee joint alignment. At 18 months of post-surgical follow-up, the child was pain-free, could perform full squats, and ambulation was near-normal, without the use of an assistive device.
Conclusions: It is feasible to develop effective, patient-specific implants for selected orthopaedic cases in a low-resourced country. This work could improve surgical and rehabilitation outcomes for selected paediatric patients and those with severe bone deformities.
(© 2023. The Author(s).)

As part of this work, polymer composites based on polycarbonate/acrylonitrile-butadiene-styrene (PC/ABS) were obtained and used in 3D printing technology, particularly Melted Extrusion Modeling (MEM) technology. The influence of selected fillers on the properties of the obtained composites was investigated. For this purpose, modified fillers such as silica modified with alumina, bentonite modified with a quaternary ammonium salt, and hybrid lignin/silicon dioxide filler were introduced into the PC/ABS matrix. In the first part of this work, polymer blends and their composites containing 1.5-3 wt. of the filler were used to obtain the filament using the proprietary technological line. Moldings for testing the performance properties were obtained using additive manufacturing techniques and injection molding. In the subsequent part of this work, rheological properties (mass flow rate (MFR) and viscosity curves) and mechanical properties (Rockwell hardness and static tensile strength with Young's modulus) were examined. The structures of the obtained composites were also determined by scanning electron microscopy (SEM/EDS). The obtained results confirmed the results obtained from a wide-angle X-ray scattering analysis (WAXS). In turn, the physicochemical properties were characterized on the basis of the results of tests using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Based on the obtained results, it was found that the introduced modified additives had a significant impact on the processing and functional properties of the tested composites.

Background: Electronic paper (E-paper) screens use electrophoretic ink to provide paper-like low-power displays with advanced networking capabilities that may potentially serve as an alternative to traditional whiteboards and television display screens in hospital settings. E-paper may be leveraged in the emergency department (ED) to facilitate communication. Providing ED patient status updates on E-paper screens could improve patient satisfaction and overall experience and provide more equitable access to their health information.
Objective: We aimed to pilot a patient-facing digital whiteboard using E-paper to display relevant orienting and clinical information in real time to ED patients. We also sought to assess patients' satisfaction after our intervention and understand our patients' overall perception of the impact of the digital whiteboards on their stay.
Methods: We deployed a 41-inch E-paper digital whiteboard in 4 rooms in an urban, tertiary care, and academic ED and enrolled 110 patients to understand and evaluate their experience. Participants completed a modified Hospital Consumer Assessment of Health Care Provider and Systems satisfaction questionnaire about their ED stay. We compared responses to a matched control group of patients triaged to ED rooms without digital whiteboards. We designed the digital whiteboard based on iterative feedback from various departmental stakeholders. After establishing IT infrastructure to support the project, we enrolled patients on a convenience basis into a control and an intervention (digital whiteboard) group. Enrollees were given a baseline survey to evaluate their comfort with technology and an exit survey to evaluate their opinions of the digital whiteboard and overall ED satisfaction. Statistical analysis was performed to compare baseline characteristics as well as satisfaction.
Results: After the successful prototyping and implementation of 4 digital whiteboards, we screened 471 patients for inclusion. We enrolled 110 patients, and 50 patients in each group (control and intervention) completed the study protocol. Age, gender, and racial and ethnic composition were similar between groups. We saw significant increases in satisfaction on postvisit surveys when patients were asked about communication regarding delays (P=.03) and what to do after discharge (P=.02). We found that patients in the intervention group were more likely to recommend the facility to family and friends (P=.04). Additionally, 96% (48/50) stated that they preferred a room with a digital whiteboard, and 70% (35/50) found the intervention "quite a bit" or "extremely" helpful in understanding their ED stay.
Conclusions: Digital whiteboards are a feasible and acceptable method of displaying patient-facing data in the ED. Our pilot suggested that E-paper screens coupled with relevant, real-time clinical data and packaged together as a digital whiteboard may positively impact patient satisfaction and the perception of the facility during ED visits. Further study is needed to fully understand the impact on patient satisfaction and experience.
Trial Registration: ClinicalTrials.gov NCT04497922; https://clinicaltrials.gov/ct2/show/NCT04497922.
(©Andrew D A Marshall, Mohammad Adrian Hasdianda, Steven Miyawaki, Guruprasad D Jambaulikar, Chenze Cao, Paul Chen, Christopher W Baugh, Haipeng Zhang, Jonathan McCabe, Lee Steinbach, Scott King, Jason Friedman, Jennifer Su, Adam B Landman, Peter Ray Chai. Originally published in JMIR Formative Research (https://formative.jmir.org), 21.03.2023.)

Introduction: No tools exist to help children with spina bifida (SB) describe their incontinence concerns and to help their providers account for them when evaluating management success. Our aim was to understand patients', parents', and clinicians' preferences about how a SB continence goal-selection tool (MyGoal-C) should look and function, and to create a tool prototype.
Methods: We used a qualitative research approach integrated with human-centered design methods. We recruited children with SB (8-17 years old), parents ( ≥ 18 years old) of children with SB (8-17 years old) in clinic and online, and urology healthcare providers at our institution. We surveyed children and parents, and conducted parent and provider Zoom-based prototyping sessions to iteratively design the app. Design researchers analyzed online activities using affinity diagramming, group analysis and modeling activities. Provider sessions were analyzed with qualitative thematic analysis based on grounded theory. Recruitment continued until saturation was reached.
Results: Thirteen children with SB participated (median age: 10 years old, 4 female, 9 shunted, 10 using bladder catheterizations). Thirty-seven parents participated (33 mothers, median age: 43 years old). Children and parents unanimously recommended an app and their comments generated 6 major theme domains: goal-setting process, in-app content, working toward goals, urology provider check-in, app customization, and using big data to improve future functionality. Twenty-one of the parents participated in 3 prototyping sessions with 6 breakout groups. The remaining 16 parents and 13 children then completed the Prototype Testing Survey, leading to a refined prototype and a visual flow map of the app experience (Figure). Feedback from 11 urology healthcare providers (7 female, 6 advanced practice providers) generated 8 themes: patient engagement/autonomy, clearly displaying results, integration into clinic workflow, not increasing clinical staff burden, potential clinician bias, parental involvement, limitations of the app, and future app adaptation. These cumulative data allowed for a construction of a final app prototype.
Comment: Findings of our study lay the foundation for creating a goal-selection app that meets preferences and needs of children, parents, and providers. Next steps involve building the app, testing its usability and assessing it prospectively in a clinical setting.
Conclusions: Children with SB and parents preferred an app to help them set and track continence goals. All stakeholders, including urology providers, offered complementary and mutually reinforcing feedback to guide the creation of an app prototype that would ultimately be integrated into a clinic visit.
(Copyright © 2023 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.)

Cell Extracts, Freezing, Saccharomyces cerevisiae metabolism, and Bacteria

Cell-free synthetic biology enables rapid prototyping of biological parts and synthesis of proteins or metabolites in the absence of cell growth constraints. Cell-free systems are frequently made from crude cell extracts, where composition and activity can vary significantly based on source strain, preparation and processing, reagents, and other considerations. This variability can cause extracts to be treated as black boxes for which empirical observations guide practical laboratory practices, including a hesitance to use dated or previously thawed extracts. To better understand the robustness of cell extracts over time, we assessed the activity of cell-free metabolism during storage. As a model, we studied conversion of glucose to 2,3-butanediol. We found that cell extracts from Escherichia coli and Saccharomyces cerevisiae subjected to an 18-month storage period and repeated freeze-thaw cycles retain consistent metabolic activity. This work gives users of cell-free systems a better understanding of the impacts of storage on extract behavior.

Background: User involvement is widely accepted as key for designing effective applied games for health. This especially holds true for children and young people as target audiences, whose abilities, needs, and preferences can diverge substantially from those of adult designers and players. Nevertheless, there is little shared knowledge about how concretely children and young people have been involved in the design of applied games, let alone consensus guidance on how to do so effectively.
Objective: The aim of this scoping review was to describe which user involvement methods have been used in the design of applied games with children and young people, how these methods were implemented, and in what roles children and young people were involved as well as what factors affected their involvement.
Methods: We conducted a systematic literature search and selection across the ACM Digital Library, IEEE Xplore, Scopus, and Web of Science databases using State of the Art through Systematic Review software for screening, selection, and data extraction. We then conducted a qualitative content analysis on the extracted data using NVivo.
Results: We retrieved 1085 records, of which 47 (4.33%) met the eligibility criteria. The chief involvement methods were participatory design (20/47, 43%) and co-design (16/47, 37%), spanning a wide range of 45 concrete activities with paper prototyping, group discussions, and playtesting being the most frequent. In only half of the studies (24/47, 51%), children and young people participated as true design partners. Our qualitative content analysis suggested 5 factors that affect their successful involvement: comprehension, cohesion, confidence, accessibility, and time constraints.
Conclusions: Co-design, participatory design, and similar high-level labels that are currently used in the field gloss over very uneven degrees of participation in design and a wide variety of implementations that greatly affect actual user involvement. This field would benefit from more careful consideration and documentation of the reason of user involvement. Future research should explore concrete activities and configurations that can address the common challenges of involving children and young people, such as comprehension, cohesion, confidence, and accessibility.
(©Michael John Saiger, Sebastian Deterding, Lina Gega. Originally published in JMIR Serious Games (https://games.jmir.org), 16.03.2023.)

Vanadium dioxide (VO 2 ) is widely employed in developing tunable optoelectronic devices due to its significant changes in optical and electric properties upon phase transition. To fabricate the VO 2 -based functional devices down to the micro/nanoscale, a high-resolution processing technique is in demand. Scanning probe lithography (SPL) on the basis of a tip-induced electric field provides a promising approach for prototyping. Here, we demonstrated a precise VO 2 etching strategy by direct writing on a VO 2 film with a negative tip bias and subsequent sonication removal of the written area. The effects of bias voltage, sonication, and thermal treatment as well as the mechanical difference between the tip-modulated area and the pristine VO 2 film were investigated systematically. The results show that VO 2 can be etched layer by layer via alternately repeating tip modulation and sonication, and arbitrary patterns can be written. Based on this route, we designed a kind of metasurface by arranging VO 2 -gold nanoblocks with different sizes and heights for spectrally selective tunable reflectivity in near- and mid-infrared. This electric-field SPL method demonstrates the prominent advantages of high resolution down to several tens of nanometers, quasi-3D patterning, and resist-free maskless direct writing, which should be applicable for prototyping other micro/nanodevices.

Algorithms, Upper Extremity, Learning, Hand, Gestures, and Neural Networks, Computer

In this paper, we present our investigation of the 2D Hand Gesture Recognition (HGR) which may be suitable for the control of the Automated Guided Vehicle (AGV). In real conditions, we deal with, among others, a complex background, changing lighting conditions, and different distances of the operator from the AGV. For this reason, in the article, we describe the database of 2D images created during the research. We tested classic algorithms and modified them by us ResNet50 and MobileNetV2 which were retrained partially using the transfer learning approach, as well as proposed a simple and effective Convolutional Neural Network (CNN). As part of our work, we used a closed engineering environment for rapid prototyping of vision algorithms, i.e., Adaptive Vision Studio (AVS), currently Zebra Aurora Vision, as well as an open Python programming environment. In addition, we shortly discuss the results of preliminary work on 3D HGR, which seems to be very promising for future work. The results show that, in our case, from the point of view of implementing the gesture recognition methods in AGVs, better results may be expected for RGB images than grayscale ones. Also using 3D imaging and a depth map may give better results.

In this paper, we report a simple, rapid, low-cost, biocompatible, and detachable microfluidic chip fabrication method for customized designs based on Parafilm ® . Here, Parafilm ® works as both a bonding agent and a functional membrane. Its high ultimate tensile stress (3.94 MPa) allows the demonstration of high-performance actuators such as microvalves and micropumps. By laser ablation and the one-step bonding of multiple layers, 3D structured microfluidic chips were successfully fabricated within 2 h. The consumption time of this method (~2 h) was 12 times less than conventional photolithography (~24 h). Moreover, the shear stress of the PMMA-Parafilm ® -PMMA specimens (0.24 MPa) was 2.13 times higher than that of the PDMS-PDMS specimens (0.08 MPa), and 0.56 times higher than that of the PDMS-Glass specimens (0.16 MPa), showing better stability and reliability. In this method, multiple easily accessible materials such as polymethylmethacrylate (PMMA), PVC, and glass slides were demonstrated and well-incorporated as our substrates. Practical actuation devices that required high bonding strength including microvalves and micropumps were fabricated by this method with high performance. Moreover, the biocompatibility of the Parafilm ® -based microfluidic devices was validated through a seven-day E. coli cultivation. This reported fabrication scheme will provide a versatile platform for biochemical applications and point-of-care diagnostics.

Background: The Quick Exposure Check (QEC) assesses four major body parts and engages users in assessing some physical interactions relevant to design in task analysis.
Objective: In this paper, we investigated the application of QEC as the ergonomic intervention to detect pre-production ergonomic design faults in the apple sorting machine by applying physical and virtual prototyping for three different tasks analysis divided into two phases (Task 1: Apple harvesting and preparation for sorting; Task 2: Sorting control and separation of waste fruits; Task 3: Transfer of separated apples).
Method: First, the QEC questionnaire was administered while Iranian participants interacted with the machine to detect abnormal posture. Second, we redesigned a concept of the machine and assessed it with QEC by a focus group.
Results: Before design, the high pressure in Task 1 is on the back (dynamic), shoulder/arm, and very high pressure in Task 2, and in Task 3 on the back (static), arm/shoulder/neck, making an uncomfortable situation for posture. After redesign, we observed decreased pressures on the back/shoulder/arm in Task 1 from high to medium, in Task 3 from very high to low, and also in Task 2, this was detectable decreasing from very high pressures on the back/shoulder/arm and the high pressures on the neck to medium.
Conclusion: Prototyping with QEC demonstrated that accurate redesigning of the machine with concentration on shifting from static tasks to dynamic or conversely, and ease of access by adjusting dimensions according to anthropometry and auxiliary products, could reduce musculoskeletal disorders.

Background: Shoulder dislocations are common occurrences, yet there are few simulation devices to train medical personnel on how to reduce these dislocations. Reductions require a familiarity with the shoulder and a nuanced motion against strong muscle tension. The goal of this work is to describe the design of an easily replicated, low-cost simulator for training shoulder reductions.
Materials and Methods: An iterative, stepwise engineering design process was used to design and implement ReducTrain. A needs analysis with clinical experts led to the selection of the traction-countertraction and external rotation methods as educationally relevant techniques to include. A set of design requirements and acceptance criteria was established that considered durability, assembly time, and cost. An iterative prototyping development process was used to meet the acceptance criteria. Testing protocols for each design requirement are also presented. Step-by-step instructions are provided to allow the replication of ReducTrain from easily sourced materials, including plywood, resistance bands, dowels, and various fasteners, as well as a 3D-printed shoulder model, whose printable file is included at a link in the Additional file 1: Appendix.
Results: A description of the final model is given. The total cost for all materials for one ReducTrain model is under US $200, and it takes about 3 h and 20 min to assemble. Based on repetitive testing, the device should not see any noticeable changes in durability after 1000 uses but may exhibit some changes in resistance band strength after 2000 uses.
Discussion: The ReducTrain device fills a gap in emergency medicine and orthopedic simulation. Its wide variety of uses points to its utility in several instructional formats. With the rise of makerspaces and public workshops, the construction of the device can be easily completed. While the device has some limitations, its robust design allows for simple upkeep and a customizable training experience.
Conclusion: A simplified anatomical design allows for the ReducTrain model to serve as a viable training device for shoulder reductions.
(© 2023. The Author(s).)

Background: Monte Carlo particle simulation has become the primary tool for designing low-energy miniature x-ray tubes due to the difficulties of physically prototyping these devices and characterizing their radiation fields. Accurate simulation of electronic interactions within their targets is necessary for modeling both photon production and heat transfer. Voxel-averaging can conceal hot spots in the target heat deposition profile that can threaten the integrity of the tube.
Purpose: This research seeks a computationally-efficient method of estimating voxel-averaging error in energy deposition simulations of electron beams penetrating thin targets to inform the appropriate scoring resolution for a desired accuracy level.
Methods: An analytical model to estimate voxel-averaging along the target depth was developed and compared to results from Geant4 via its wrapper, TOPAS. A 200 keV planar electron beam was simulated to impinge tungsten targets of thicknesses between 1.5- and 12.5- μ m ${{\umu {\rm m}}}$ . For each target, the model was used to calculate the energy deposition ratio between voxels of varying sizes centered on the longitudinal midpoint of the target. Model-calculated ratios were compared to simulation outputs to gauge the model's accuracy. Then, the model was used to approximate the error between the point value of electron energy deposition and a voxel-based measurement.
Results: The model underestimates error to within 5% for targets less than 7.5- μ m ${{\umu {\rm m}}}$ in thickness with increasing error for greater thicknesses. For the 1.5- μ m ${{\umu {\rm m}}}$ target, calculations of the point-vs.-voxel energy deposition show an 11% averaging effect between the midpoint and a 1.5- μ m ${{\umu {\rm m}}}$ voxel. Energy deposition profiles along the target depth were also calculated in the Monte Carlo for reference.
Conclusion: A simple analytical model was developed with reasonable accuracy to guide Monte Carlo users in estimating the appropriate depth-voxel size for thin-target x-ray tube simulations. This methodology can be adapted for other radiological contexts to increase robustness in point-value estimations.
(© 2023 American Association of Physicists in Medicine.)

Humans, Communication, Software, and Language

Amidst the domestic labor shortage and worldwide pandemic in recent years, there has been an urgent need for a digital means that allows construction site workers, particularly site managers, to obtain information more efficiently in support of their daily managerial tasks. For workers who move around the site, traditional software applications that rely on a form-based interface and require multiple finger movements such as key hits and clicks can be inconvenient and reduce their willingness to use such applications. Conversational AI, also known as a chatbot, can improve the ease of use and usability of a system by providing an intuitive interface for user input. This study presents a demonstrative Natural Language Understanding (NLU) model and prototypes an AI-based chatbot for site managers to inquire about building component dimensions during their daily routines. Building Information Modeling (BIM) techniques are also applied to implement the answering module of the chatbot. The preliminary testing results show that the chatbot can successfully predict the intents and entities behind the inquiries raised by site managers with satisfactory accuracy for both intent prediction and the answer. These results provide site managers with alternative means to retrieve the information they need.

Nowadays, lab-on-chip (LOC) devices are attracting more and more attention since they show vast prospects for various biomedical applications. Usually, an LOC is a small device that serves a single laboratory function. LOCs show massive potential for organ-on-chip (OOC) device manufacturing since they could allow for research on the avoidance of various diseases or the avoidance of drug testing on animals or humans. However, this technology is still under development. The dominant technique for the fabrication of such devices is molding, which is very attractive and efficient for mass production, but has many drawbacks for prototyping. This article suggests a femtosecond laser microprocessing technique for the prototyping of an OOC-type device-a liver-on-chip. We demonstrate the production of liver-on-chip devices out of glass by using femtosecond laser-based selective laser etching (SLE) and laser welding techniques. The fabricated device was tested with HepG2(GS) liver cancer cells. During the test, HepG2(GS) cells proliferated in the chip, thus showing the potential of the suggested technique for further OOC development.

The review aimed at analyzing the evidence available on 3D printable materials and techniques used for the fabrication of orthodontic appliances, focusing on materials properties that are clinically relevant. MEDLINE/PubMed, Scopus, and Cochrane Library databases were searched. Starting from an initial retrieval of 669 citations, 47 articles were finally included in the qualitative review. Several articles presented proof-of-concept clinical cases describing the digital workflow to manufacture a variety of appliances. Clinical studies other than these case reports are not available. The fabrication of aligners is the most investigated application of 3D printing in orthodontics, and, among materials, Dental LT Clear Resin (Formlabs) has been tested in several studies, although Tera Harz TC-85 (Graphy) is currently the only material specifically marketed for direct printing of aligners. Tests of the mechanical properties of aligners materials lacked homogeneity in the protocols, while biocompatibility tests failed to assess the influence of intraoral conditions on eluents release. The aesthetic properties of 3D-printed appliances are largely unexplored. The evidence on 3D-printed metallic appliances is also limited. The scientific evidence on 3D printable orthodontic materials and techniques should be strengthened by defining international standards for laboratory testing and by starting the necessary clinical trials.

In factories, energy conservation is a crucial issue. The co-fabrication space is a modern-day equivalent of a new factory type, and it makes use of Internet of Things (IoT) devices, such as sensors, software, and online connectivity, to keep track of various building features, analyze data, and produce reports on usage patterns and trends that can be used to improve building operations and the environment. The co-fabrication user requires dynamic and flexible space, which is different from the conventional user's usage. Because the user composition in a co-fabrication space is dynamic and unstable, we cannot use the conventional approach to assess their usage and rentals. Prototyping necessitates a specifically designed energy-saving strategy. The research uses a "seeing-moving-seeing" design thinking framework, which enables designers to more easily convey their ideas to others through direct observation of the outcomes of their intuitive designs and the representation of their works through design media. The three components of human behavior, physical manufacture, and digital interaction are primarily the focus of this work. The computing system that connects the physical machine is created through communication between the designer and the digital interface, giving the designer control over the physical machine. It is an interactive fabrication process formed by behavior. The Sensible Energy System+ is an interactive fabrication process of virtual and real coexistence created by combining the already-existing technology, the prototype fabrication machine, and SENS. This process analyzes each step of the fabrication process and energy, fits it into the computing system mode to control the prototype fabrication machine, and reduces the problem between virtual and physical fabrication and energy consumption.

Humans, Printing, Three-Dimensional, Research Design, Occupational Therapists, and Self-Help Devices

In this study, we conducted four participatory workshops to facilitate co-designing 12 writing assistive technology (AT) interventions with occupational therapists, industrial designers, and an end-user with physical impairments. We observed participants' activities during the workshops and held a post-workshop follow-up reflection session where we invited the OTs and the end-user to share their experience about the co-design activities and co-created devices. The study findings revealed characteristics of the clinical-technical-individual co-design contributions that are conducive to the collective making of usable and useful AT prototypes. We propose CoDEA (Codesigning Assistive Technologies), a potential framework that offers to follow four stages of co-experimentation, co-development, co-evaluation, and co-refinement and define specific roles and activities of OT-designer-user in each step to co-design 3D printed ATs successfully. We recommend utilizing a comprehensive approach to co-designing ATs by using prototyping toolkits/3D printing together with a designerly way of thinking to achieve state-of-the-art AT solutions.

A flexible power electronic converter embedding a rapid control prototyping platform suitable to be applied in research test setups and teaching laboratories is proposed and described in this paper. The electronic system is composed of three subsystems, namely, i ) three half-bridge power boards, ii ) a dc-link capacitor bank with a half-bridge power module for active dc-link control, iii ) an interfacing board, called motherboard, to couple the power modules with a control unit, iv ) a digital control unit with rapid control prototyping functionalities for controlling power electronic circuits. Power modules integrate sensors with related conditioning circuits, driving circuits for power switches, and protection circuits. Conversion circuits exploit GaN electronic switches for optimal performance. The architecture and implementation of the system are described in detail in this manuscript. Main applications are in the implementation of conversion circuits for supplying arbitrary ac or dc voltages or currents, testing of new control algorithms for power electronic converters, testing of systems of electronic converters in, for example, smart nanogrids or renewable energy applications, training of undergraduate and graduate students.
Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(© 2023 The Author(s).)