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Female, Humans, Pilot Projects, Endoscopes, Fallopian Tubes, Ovarian Neoplasms diagnostic imaging, and Ovarian Neoplasms pathology

Significance: High grade serous ovarian cancer is the most deadly gynecological cancer, and it is now believed that most cases originate in the fallopian tubes (FTs). Early detection of ovarian cancer could double the 5-year survival rate compared with late-stage diagnosis. Autofluorescence imaging can detect serous-origin precancerous and cancerous lesions in ex vivo FT and ovaries with good sensitivity and specificity. Multispectral fluorescence imaging (MFI) can differentiate healthy, benign, and malignant ovarian and FT tissues. Optical coherence tomography (OCT) reveals subsurface microstructural information and can distinguish normal and cancerous structure in ovaries and FTs.
Aim: We developed an FT endoscope, the falloposcope, as a method for detecting ovarian cancer with MFI and OCT. The falloposcope clinical prototype was tested in a pilot study with 12 volunteers to date to evaluate the safety and feasibility of FT imaging prior to standard of care salpingectomy in normal-risk volunteers. In this manuscript, we describe the multiple modifications made to the falloposcope to enhance robustness, usability, and image quality based on lessons learned in the clinical setting.
Approach: The ∼ 0.8    mm diameter falloposcope was introduced via a minimally invasive approach through a commercially available hysteroscope and introducing a catheter. A navigation video, MFI, and OCT of human FTs were obtained. Feedback from stakeholders on image quality and procedural difficulty was obtained.
Results: The falloposcope successfully obtained images in vivo . Considerable feedback was obtained, motivating iterative improvements, including accommodating the operating room environment, modifying the hysteroscope accessories, decreasing endoscope fragility and fiber breaks, optimizing software, improving fiber bundle images, decreasing gradient-index lens stray light, optimizing the proximal imaging system, and improving the illumination.
Conclusions: The initial clinical prototype falloposcope was able to image the FTs, and iterative prototyping has increased its robustness, functionality, and ease of use for future trials.
(© 2023 The Authors.)

Carrageenan pharmacology, Carrageenan chemistry, Wound Healing, Biocompatible Materials chemistry, Hydrogels pharmacology, Hydrogels chemistry, Gelatin pharmacology, and Gelatin chemistry

Injectable hydrogels based on natural polymers have shown great potential for various tissue engineering applications, such as wound healing. However, poor mechanical properties and weak self-healing ability are still major challenges. In this work, we introduce a host-guest (HG) supramolecular interaction between acrylate-β-cyclodextrin (Ac-β-CD) conjugated on methacrylated kappa-carrageenan (MA-κ-CA) and aromatic residues on gelatin to provide self-healing characteristics. We synthesize an MA-κ-CA to conjugate Ac-β-CD and fabricate dual crosslinked hybrid hydrogels with gelatin to mimic the native extracellular matrix (ECM). The dual crosslinking occurs on the MA-κ-CA backbone through the addition of KCl and photocrosslinking process, which enhances mechanical strength and stability. The hybrid hydrogels exhibit shear-thinning, self-healing, and injectable behavior, which apply easily under a minimally invasive manner and contribute to shear stress during the injection. In-vitro studies indicate enhanced cell viability. Furthermore, scratch assays are performed to examine cell migration and cell-cell interaction. It is envisioned that the combination of self-healing and injectable dual crosslinked hybrid hydrogels with HG interactions display a promising and functional biomaterial platform for wound healing applications.
(© 2023 Wiley Periodicals LLC.)

Synthetic Biology, Biotechnology, Bioengineering, Microalgae genetics, Microalgae metabolism, and Biosensing Techniques

Biosensors are powerful tools to investigate, phenotype, improve and prototype microbial strains, both in fundamental research and in industrial contexts. Genetic and biotechnological developments now allow the implementation of synthetic biology approaches to novel different classes of microbial hosts, for example photosynthetic microalgae, which offer unique opportunities. To date, biosensors have not yet been implemented in phototrophic eukaryotic microorganisms, leaving great potential for novel biological and technological advancements untapped. Here, starting from selected biosensor technologies that have successfully been implemented in heterotrophic organisms, we project and define a roadmap on how these could be applied to microalgae research. We highlight novel opportunities for the development of new biosensors, identify critical challenges, and finally provide a perspective on the impact of their eventual implementation to tackle research questions and bioengineering strategies. From studying metabolism at the single-cell level to genome-wide screen approaches, and assisted laboratory evolution experiments, biosensors will greatly impact the pace of progress in understanding and engineering microalgal metabolism. We envision how this could further advance the possibilities for unraveling their ecological role, evolutionary history and accelerate their domestication, to further drive them as resource-efficient production hosts.
Competing Interests: Declaration of Competing Interest The authors declare no conflicts of interest.
(Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Water Quality

An implementation proposal that seeks to globalize the scope of the sustainable technologies developed in the University laboratories is presented. This approach uses the generation of triple-impact projects placing people at the center of technological development to bring technical and scientific knowledge into a service design oriented to global sustainable solutions. This research is an approach to what a hub for scientific research, technological implementation, and human needs would look like by designing common environments in which to interact and expand knowledge in an iterated way through the experience of all the actors involved in technological implementation. As a control case, a new technology developed at the Universidad de Buenos Aires, consisting of using sustainable materials as tubular reactor fillers for water treatment was chosen. Based on data obtained within the framework of a University extension project, in which the water quality diagnosis for human consumption was carried out and cross-examined with the mathematical analysis of sorption, design parameters of the reactor, participatory design, and open source concepts application, different virtual environments were generated with distinct objectives: i) open design environment: publishing and mapping of installed sorption reactors, reactor model plans, and useful information related to drinking water quality (aimed at contributors of the open source design environment); ii) platform for academic actors linking: connecting data between prototyping lab for participatory design of sorption reactors (aimed at university research users); iii) information disclosure page: space where the implemented technology impact is displayed and shows options to contact researchers and request a reactor design diagnosis for another community (aimed at beneficiary users). A technological service designed to link the University with the community was proposed, by resolving one of the main gaps related to the possibility for communities to access public financing for self-managed improvement projects, increasing the appropriation of the adopted technology and democratizing public investment, making it sustainable over time.
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.)

With the characteristics of fast prototyping and personalized manufacturing, 3D-printing (three-dimensional printing) is an emerging technology with promising applications for orthopedic medical devices. It can complete the process of medical devices with complex shape which can not be completed by conventional fabrication process. At present, a variety of orthopedic medical devices manufactured by 3D printing technology, has been approved for marketing, and their use has been proved to be beneficial. 3D bioprinting in this area has also made a few breakthroughs. However, many challenges still remain to be addressed as well. In this study, the research status, as well as the development of the 3D-printing technology in the field of orthopedic medical devices is elaborated.

Although cell-free protein expression has been widely used for the synthesis of single proteins, cell-free synthetic biology has rapidly expanded to new, more complex applications. One such application is the prototyping or implementation of complex genetic networks involving the expression of multiple proteins at precise ratios, often from different plasmids. However, expression of multiple proteins from multiple plasmids may inadvertently result in unexpected, off-target changes to the levels of the proteins being expressed, a phenomenon termed plasmid crosstalk. Here, we show that the effects of plasmid crosstalk─even at the qualitative level of increases vs decreases in protein expression─depend on the concentration of plasmids in the reaction and the type of transcriptional machinery involved in the expression. This crosstalk can have a significant impact on genetic circuitry function and even interpretation of simple experimental results and thus should be taken into consideration during the development of cell-free applications.

The integration of two-dimensional (2D) van der Waals materials with nanostructures has triggered a wide spectrum of optical and optoelectronic applications. Photonic structures of conventional materials typically lack efficient reconfigurability or multifunctionality. Atomically thin 2D materials can thus generate new functionality and reconfigurability for a well-established library of photonic structures such as integrated waveguides, optical fibers, photonic crystals, and metasurfaces, to name a few. Meanwhile, the interaction between light and van der Waals materials can be drastically enhanced as well by leveraging micro-cavities or resonators with high optical confinement. The unique van der Waals surfaces of the 2D materials enable handiness in transfer and mixing with various prefabricated photonic templates with high degrees of freedom, functionalizing as the optical gain, modulation, sensing, or plasmonic media for diverse applications. Here, we review recent advances in synergizing 2D materials to nanophotonic structures for prototyping novel functionality or performance enhancements. Challenges in scalable 2D materials preparations and transfer, as well as emerging opportunities in integrating van der Waals building blocks beyond 2D materials are also discussed.

The continuous growth of annual production and consumption of polyethylene terephthalate (PET) is coined with increasing waste that leaks into the environment, landfills and oceans as microplastics and nano plastics fragments. Upcycling the recycled PET to make a feedstock for the fast-growing material-extrusion additive manufacturing (MEX-AM) technology can contribute to the solution and supports the concept of sustainable materials. In this work, extrudable filaments comprising recycled polyethylene terephthalate (rPET) with low-cost additives, such as pyromellitic dianhydride (PMDA) as a chain extender, styrene-ethylene-butylene-styrene terpolymer functionalized with maleic anhydride (SEBS-g-MA), a thermal modifier and toughening agent, ethylene-ethyl acrylate-glycidyl methacrylate terpolymer (E-EA-GMA), a functional reactive elastomeric impact modifier and ethylene-ethyl-acrylate (EEA), a non-reactive elastomeric impact modifier, have been fabricated using the twin-screw extruder. The optimum extrusion process parameters for producing uniform filaments of different rPET compounded formulations have been identified, this includes the extrusion die temperature of 280 °C and the screw speed of 150 ± 3 rpm. The compounded filaments are then printed into standard ASTM test specimens for thermal characterization and mechanical characterization, including glass transition and melting temperatures, crystallinity and crystallization temperature, tensile strength, tensile modulus, ductility, flexural strength, and Izod impact energy. Furthermore, the melt flow index for the filaments was measured. More significantly, the experimental data showed that compounding rPET with such additives in the reactive twin-screw extrusion process results in uniform filaments that display advantageous thermal and mechanical properties and can be used as a feedstock in the MEX-AM technology. This study suggests that compounding the recycled PET pellets with low-cost additives while extruding them into filaments for MEX-AM offers excellent potential to make high-value-added customized products from a sustainable polymer feedstock, such as prototyping, tooling, testing components or end-use internal components for small machines and cars.
(© 2023. Springer Nature Limited.)

Electric Impedance, Carbon, Electrodes, Microphysiological Systems, and Polymethyl Methacrylate

Trans-endothelial electrical resistance (TEER) is one of the most widely used indicators to quantify the barrier integrity of endothelial layers. Over the last decade, the integration of TEER sensors into organ-on-a-chip (OOC) platforms has gained increasing interest for its efficient and effective measurement of TEER in OOCs. To date, microfabricated electrodes or direct insertion of wires has been used to integrate TEER sensors into OOCs, with each method having advantages and disadvantages. In this study, we developed a TEER-SPE chip consisting of carbon-based screen-printed electrodes (SPEs) embedded in a poly(methyl methacrylate) (PMMA)-based multi-layered microfluidic device with a porous poly(ethylene terephthalate) membrane in-between. As proof of concept, we demonstrated the successful cultures of hCMEC/D3 cells and the formation of confluent monolayers in the TEER-SPE chip and obtained TEER measurements for 4 days. Additionally, the TEER-SPE chip could detect changes in the barrier integrity due to shear stress or an inflammatory cytokine (i.e., tumor necrosis factor-α). The novel approach enables a low-cost and facile fabrication of carbon-based SPEs on PMMA substrates and the subsequent assembly of PMMA layers for rapid prototyping. Being cost-effective and cleanroom-free, our method lowers the existing logistical and technical barriers presenting itself as another step forward to the broader adoption of OOCs with TEER measurement capability.
(© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

The protection and interrogation of pancreatic β-cell health and function ex vivo is a fundamental aspect of diabetes research, including mechanistic studies, evaluation of β-cell health modulators, and development and quality control of replacement β-cell populations. However, present-day islet culture formats, including traditional suspension culture as well as many recently developed microfluidic devices, suspend islets in a liquid microenvironment, disrupting mechanochemical signaling normally found in vivo and limiting β-cell viability and function in vitro . Herein, we present a novel three-dimensional (3D) microphysiological system (MPS) to extend islet health and function ex vivo by incorporating a polymerizable collagen scaffold to restore biophysical support and islet-collagen mechanobiological cues. Informed by computational models of gas and molecular transport relevant to β-cell physiology, a MPS configuration was down-selected based on simulated oxygen and nutrient delivery to collagen-encapsulated islets, and 3D-printing was applied as a readily accessible, low-cost rapid prototyping method. Recreating critical aspects of the in vivo microenvironment within the MPS via perfusion and islet-collagen interactions mitigated post-isolation ischemia and apoptosis in mouse islets over a 5-day period. In contrast, islets maintained in traditional suspension formats exhibited progressive hypoxic and apoptotic cores. Finally, dynamic glucose-stimulated insulin secretion measurements were performed on collagen-encapsulated mouse islets in the absence and presence of well-known chemical stressor thapsigargin using the MPS platform and compared to conventional protocols involving commercial perifusion machines. Overall, the MPS described here provides a user-friendly islet culture platform that not only supports long-term β-cell health and function but also enables multiparametric evaluations.

Objective: Design thinking is a creative problem-solving process used to better understand users' needs and experiences so that a product or service can be improved. Its emphasis on empathy, iterative prototyping, and participatory collaboration make it an ideal methodology for innovation in medical education. We apply this framework to the virtual rheumatology fellowship interview process so that interviews can become more applicant centered.
Methods: This educational quality improvement project uses a design-thinking framework to identify opportunities and challenges for rheumatology fellowship applicants. The investigators use the 5-step process (Empathize, Define, Ideate, Prototype, Test) and incorporate rapid qualitative analysis of semistructured interviews to innovate the interview experience. The iterative and collaborative nature of this process has empowered participants to codesign an applicant-centered interview experience.
Results: Interviews with fellowship applicants (n = 9), fellow physicians (n = 4), and faculty members (n = 3) identified three major dynamics of the interview process: (1) Is it a safe environment to ask questions? (2) How do I exchange information effectively? and (3) How do I fit all these data into the bigger picture? Creative brainstorming techniques at a series of three workshops yielded four prototypes emphasizing customization, hybridization, facilitation, and preparation. A finalized applicant-centered interview template was devised in preparation for the 2023-2024 application season.
Conclusion: Design thinking has yielded insights into three important dynamics that drive applicant experiences. These insights allow for a redesign of processes so that virtual interviews can be more applicant centered. This framework allows for further iterations and modifications as the needs of applicants and programs evolve over time.
(© 2023 The Authors. ACR Open Rheumatology published by Wiley Periodicals LLC on behalf of American College of Rheumatology.)

Magnetically hard materials are widely used to build soft magnetic robots, providing large magnetic force/torque and macrodomain programmability. However, their high magnetic coercivity often presents practical challenges when attempting to reconfigure magnetization patterns, requiring a large magnetic field or heating. In this study, we introduce magnetic putty as a magnetically hard and soft material with large remanence and low coercivity. We show that the magnetization of magnetic putty can be easily reoriented with maximum magnitude using an external field that is only one tenth of its coercivity. Additionally, magnetic putty is a malleable, autonomous self-healing material that can be recycled and repurposed. We anticipate magnetic putty could provide a versatile and accessible tool to various magnetic robotics applications for fast prototyping and explorations for research and educational purposes. This article is protected by copyright. All rights reserved.
(This article is protected by copyright. All rights reserved.)

In a world grappling with environmental challenges and the need for sustainable manufacturing practices, the convergence of 3D printing and recycling emerges as a promising solution. This research paper explores the potential of combining these two technologies and comprehensively analyses their synergistic effects. The study delves into the printability of recycled materials, evaluating their suitability for 3D printing and comparing their performance with conventional materials. The environmental impact of 3D printing with recycled materials is examined through a sustainability analysis and a life cycle assessment of recycled 3D printed objects. The findings reveal significant benefits, including enhanced resource efficiency, waste reduction, and customisation possibilities. The research also identifies challenges and opportunities for scaling up the use of recycled materials in 3D printing, highlighting the importance of collaboration, innovation, and regulations. With potential applications spanning various industries, from prototyping to construction and healthcare, the implications of this research are far-reaching. By embracing sustainable practices, industry collaboration, and innovation, the integration of 3D printing and recycling can pave the way for a more sustainable future, where resource conservation, circularity, and customised production are at the forefront of manufacturing.
(Copyright © 2023. Published by Elsevier B.V.)

Background: Increased levels of physical activity are associated with beneficial health effects for people with type 2 diabetes, cardiovascular disease and/or severe obesity; however, transforming knowledge about these effects into action is challenging. The aim of this paper is to explore lessons learnt from a co-creation process in a partnership project involving local stakeholders, including citizens, and researchers. The purpose of the process was to link a public health care institution with civil society organisations in the local community to make it possible for citizens to continue to be physically active after ending their public rehabilitation. Secondarily, this paper aims to develop a conceptual model of the above process.
Methods: The study constitutes the first part of Project Active Communities and was based on a partnership between three research institutions and a Danish rural municipality, involving municipal and civil society stakeholders and citizens with type 2 diabetes, cardiovascular disease and/or severe obesity in co-creation of concrete interventions for implementation. The co-creation process was divided into two tracks, one involving citizens (two workshops) and one involving municipal and civil society stakeholders (two workshops). The two tracks were concluded with a final workshop involving all stakeholders, including local politicians. Data sources are focus groups and bilateral meetings, workshop observations, and questionnaires.
Results: Lessons learnt include the importance of having a flexible timeframe for the co-creation process; giving room for disagreements and matching of mutual expectations between stakeholders; the value of a coordinator in the municipality to achieve acceptance of the project; and the significance of engaging local politicians in the co-creation process to accommodate internal political agendas. We have developed a conceptual model for a co-creation process, where we outline and explain three distinct phases: stakeholder identification and description, co-creation, and prototyping. The model can be adapted and applied to other sectors and settings.
Conclusions: This study documents lessons learnt in a co-creation process aiming to link a public health care institution with civil society organisations in the local community. Further, this study has specified productive co-creative processes and documented the various phases in a conceptual model.
(© 2023. BioMed Central Ltd., part of Springer Nature.)

Introduction: Outpatient monitoring of children using invasive home mechanical ventilation (IHMV) is recommended, but access to care can be difficult. This study tested if remote (home-based) data collection was feasible and acceptable in chronic IHMV management.
Methods: A codesign study was conducted with an IHMV program, home nurses, and English- and Spanish-speaking parent-guardians of children using IHMV (0-17 years; n = 19). After prototyping, parents used a remote patient monitoring (RPM) bundle to collect patient heart rate, respiratory rate (RR), oxygen saturation, end-tidal carbon dioxide (EtCO 2 ), and ventilator pressure/volume over 8 weeks. User feedback was analyzed using qualitative methods and the System Usability Scale (SUS). Expected marginal mean differences within patient measures when awake, asleep, or after a break were calculated using mixed effects models.
Results: Patients were a median 2.9 years old and 11 (58%) took breaks off the ventilator. RPM data were entered on a mean of 83.7% (SD ± 29.1%) weeks. SUS scores were 84.8 (SD ± 10.5) for nurses and 91.8 (SD ± 10.1) for parents. Over 90% of parents agreed/strongly agreed that RPM data collection was feasible and relevant to their child's care. Within-patient comparisons revealed that EtCO 2 (break-vs-asleep 2.55 mmHg, d = 0.79 [0.42-1.15], p < .001; awake-vs-break 1.48, d = -0.49 [0.13-0.84], p = .02) and RR (break-vs-asleep 16.14, d = 2.12 [1.71-2.53], p < .001; awake-vs-break 3.44, d = 0.45 [0.10-0.04], p = .03) were significantly higher during ventilator breaks.
Conclusions: RPM data collection in children with IHMV was feasible, acceptable, and captured clinically meaningful vital sign changes during ventilator breaks, supporting the clinical utility of RPM in IHMV management.
(© 2023 The Authors. Pediatric Pulmonology published by Wiley Periodicals LLC.)

Humans, Skin microbiology, Propionibacterium acnes genetics, Synthetic Biology, Acne Vulgaris genetics, and Acne Vulgaris microbiology

In the past few years, new bacterial-cell-free transcription-translation systems have emerged as potent and quick platforms for protein production as well as for prototyping of DNA regulatory elements, genetic circuits, and metabolic pathways. The Gram-positive commensal Cutibacterium acnes is one of the most abundant bacteria present in the human skin microbiome. However, it has recently been reported that some C. acnes phylotypes can be associated with common inflammatory skin conditions, such as acne vulgaris, whereas others seem to play a protective role, acting as possible "skin probiotics". This fact has made C. acnes become a bacterial model of interest for the cosmetic industry. In the present study we report for the first time the development and optimization of a C. acnes -based cell-free system (CFS) that is able to produce 85 μg/mL firefly luciferase. We highlight the importance of harvesting the bacterial pellet in mid log phase and maintaining CFS reactions at 30 °C and physiological pH to obtain the optimal yield. Additionally, a C. acnes promoter library was engineered to compare coupled in vitro TX-TL activities, and a temperature biosensor was tested, demonstrating the wide range of applications of this toolkit in the synthetic biology field.

Reconfigurable modular microfluidics presents an opportunity for flexibly constructing prototypes of advanced microfluidic systems. Nevertheless, the strategy of directly integrating modules cannot easily fulfill the requirements of common applications, e.g., the incorporation of materials with biochemical compatibility and optical transparency and the execution of small batch production of disposable chips for laboratory trials and initial tests. Here, we propose a manufacturing scheme inspired by the movable type printing technique to realize 3D free-assembly modular microfluidics. Double-layer 3D microfluidic structures can be produced by replicating the assembled molds. A library of modularized molds is presented for flow control, droplet generation and manipulation and cell trapping and coculture. In addition, a variety of modularized attachments, including valves, light sources and microscopic cameras, have been developed with the capability to be mounted onto chips on demand. Microfluidic systems, including those for concentration gradient generation, droplet-based microfluidics, cell trapping and drug screening, are demonstrated. This scheme enables rapid prototyping of microfluidic systems and construction of on-chip research platforms, with the intent of achieving high efficiency of proof-of-concept tests and small batch manufacturing.
Competing Interests: Conflict of interestThe authors declare no competing interests.
(© Aerospace Information Research Institute, Chinese Academy of Sciences 2023.)

Clothing fit and pressure comfort play important role in clothing comfort, especially in medical body sculpting clothing (MBSC). In the present study, different body movements (forward bending, side bending, and twisting) were adopted to simulate and investigate the biomechanical stress distribution of the human body with three kinds of porosity inelastic MBSCs through the finite element analysis method. The elastic modulus of the investigated MBSCs was also measured by means of tensile testing. Analytical results showed that in the compression region during body movements, the investigated inelastic MBSCs endured less compression stress, and most of the stress was transmitted to the human body. Moreover, the stresses on the body surface were decreased with the porosity increasing. However, most of the von Mises stresses on the human body were in the desired pressure comfort range. Therefore, these results could provide potential information in the modification of MBSC for medical applications.
Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Shyuan-Yow Chen reports financial support was provided by Cathay General Hospital. Jia-Wei You reports financial support was provided by Taipei Medical University Hospital.
(Copyright © 2023. Published by Elsevier Ltd.)

Three-dimensional (3D)/four-dimensional (4D) printing, also known as additive manufacturing or fast prototyping, is a manufacturing technique that uses a digital model to generate a 3D/4D solid product. The usage of biomaterials with 3D/4D printers in the pharma and healthcare industries is gaining significant popularity. 3D printing has mostly been employed in the domain of otolaryngology to build portable anatomical models, personalized patient-centric implants, biologic tissue scaffolds, surgical planning in individuals with challenging conditions, and surgical training. Although identical to 3D printing technology in this application, 4D printing technology comprises a fourth dimension of time. With the use of 4D printing, a printed structure may alter over time under various stimuli. Smart polymeric materials are also generally denoted as bioinks are frequently employed in tissue engineering applications of 3D/4D printing. In general, 4D printing could significantly improve the safety and efficacy of otolaryngology therapies. The use of bioprinting in otolaryngology has an opportunity to transform the treatment of diseases influencing the ear, nose, and throat as well as the field of tissue regeneration. The present review briefs on polymeric material including biomaterials and cells used in the manufacturing of patient centric 3D/4D bio-printed products utilized in management of otolaryngology.
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 Vyas, Shah, Singh and Prajapati.)

Humans, Ankle, Muscles, Walking, Knee Joint, Fatigue, Walking Speed, and Foot Orthoses

Background: The stiffness of a dorsal leaf AFO that minimizes walking energy cost in people with plantarflexor weakness varies between individuals. Using predictive simulations, we studied the effects of plantarflexor weakness, passive plantarflexor stiffness, body mass, and walking speed on the optimal AFO stiffness for energy cost reduction.
Methods: We employed a planar, nine degrees-of-freedom musculoskeletal model, in which for validation maximal strength of the plantar flexors was reduced by 80%. Walking simulations, driven by minimizing a comprehensive cost function of which energy cost was the main contributor, were generated using a reflex-based controller. Simulations of walking without and with an AFO with stiffnesses between 0.9 and 8.7 Nm/degree were generated. After validation against experimental data of 11 people with plantarflexor weakness using the Root-mean-square error (RMSE), we systematically changed plantarflexor weakness (range 40-90% weakness), passive plantarflexor stiffness (range: 20-200% of normal), body mass (+ 30%) and walking speed (range: 0.8-1.2 m/s) in our baseline model to evaluate their effect on the optimal AFO stiffness for energy cost minimization.
Results: Our simulations had a RMSE < 2 for all lower limb joint kinetics and kinematics except the knee and hip power for walking without AFO. When systematically varying model parameters, more severe plantarflexor weakness, lower passive plantarflexor stiffness, higher body mass and walking speed increased the optimal AFO stiffness for energy cost minimization, with the largest effects for severity of plantarflexor weakness.
Conclusions: Our forward simulations demonstrate that in individuals with bilateral plantarflexor the necessary AFO stiffness for walking energy cost minimization is largely affected by severity of plantarflexor weakness, while variation in walking speed, passive muscle stiffness and body mass influence the optimal stiffness to a lesser extent. That gait deviations without AFO are overestimated may have exaggerated the required support of the AFO to minimize walking energy cost. Future research should focus on improving predictive simulations in order to implement personalized predictions in usual care. Trial Registration Nederlands Trial Register 5170. Registration date: May 7th 2015.  http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=5170.
(© 2023. BioMed Central Ltd., part of Springer Nature.)

Animals, Mice, Dimethylpolysiloxanes, Disease Models, Animal, Wound Healing, and Capillary Tubing

The development of wearable bioelectronic systems is a promising approach for optimal delivery of therapeutic treatments. These systems can provide continuous delivery of ions, charged biomolecules, and an electric field for various medical applications. However, rapid prototyping of wearable bioelectronic systems for controlled delivery of specific treatments with a scalable fabrication process is challenging. We present a wearable bioelectronic system comprised of a polydimethylsiloxane (PDMS) device cast in customizable 3D printed molds and a printed circuit board (PCB), which employs commercially available engineering components and tools throughout design and fabrication. The system, featuring solution-filled reservoirs, embedded electrodes, and hydrogel-filled capillary tubing, is assembled modularly. The PDMS and PCB both contain matching through-holes designed to hold metallic contact posts coated with silver epoxy, allowing for mechanical and electrical integration. This assembly scheme allows us to interchange subsystem components, such as various PCB designs and reservoir solutions. We present three PCB designs: a wired version and two battery-powered versions with and without onboard memory. The wired design uses an external voltage controller for device actuation. The battery-powered PCB design uses a microcontroller unit to enable pre-programmed applied voltages and deep sleep mode to prolong battery run time. Finally, the battery-powered PCB with onboard memory is developed to record delivered currents, which enables us to verify treatment dose delivered. To demonstrate the functionality of the platform, the devices are used to deliver H[Formula: see text] in vivo using mouse models and fluoxetine ex vivo using a simulated wound environment. Immunohistochemistry staining shows an improvement of 35.86% in the M1/M2 ratio of H[Formula: see text]-treated wounds compared with control wounds, indicating the potential of the platform to improve wound healing.
(© 2023. Springer Nature Limited.)

Background: An active online learning environment enables 2-way communication wherein students can engage in problem-based learning and projects, unlike fragmented lecture-style classes.
Purpose: This pilot study aimed to develop a metaverse-based online learning system and evaluate its usability.
Methods: A rapid prototyping model and Gather.town was used to design and develop a metaverse classroom. Participants were 10 nursing students from a college in South Korea. To evaluate usability, 10 tasks were configured and 2 pilot tests were conducted. The degree of difficulty, time required to perform tasks, and students' experience were investigated.
Results: The Metaverse for Education of Nursing Students was successfully completed, incorporating student feedback and addressing identified areas for improvement.
Conclusion: This study reflects a learner-centered educational environment through the direct participation in the development process of the instructors who conducted the lectures. The metaverse space can be widely applied in creative nursing education in the future.
Competing Interests: The authors disclose no conflicts of interest.
(Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Introduction: In-person dermatology clinical research studies often face recruitment and participation challenges due to travel-, time-, and cost-associated barriers. Studies incorporating virtual/asynchronous formats can potentially enhance research subject participation and satisfaction, but few mobile health tools are available to enable remote study conduct. We developed SkinTracker, a patient-facing mobile app and researcher-facing web platform, that enables longitudinal collection of skin photos, patient reported outcomes, and biometric health and environmental data.
Methods: Eight design thinking sessions including dermatologists, clinical research staff, software engineers, and graphic designers were held to create the components of SkinTracker. Following iterative prototyping, SkinTracker was piloted across six adult and four pediatric subjects with atopic dermatitis (AD) of varying severity levels to test and provide feedback on SkinTracker for six months.
Results: The SkinTracker app enables collection of informed consent for study participation, baseline medical history, standardized skin photographs, patient-reported outcomes (e.g., Patient Oriented Eczema Measure (POEM), Pruritus Numerical Rating Scale (NRS), Dermatology Life Quality Index (DLQI)), medication use, adverse events, voice diary to document qualitative experiences, chat function for communication with research team, environmental and biometric data such as exercise and sleep metrics through integration with an Apple Watch. The researcher web portal allows for management and visualization of subject enrollment, skin photographs for examination and severity scoring, survey completion, and other patient modules. The pilot study requested that subjects complete surveys and photographs on a weekly to monthly basis via the SkinTracker app. Afterwards, participants rated their experience in a 7-item user experience survey covering app function, design, and desire for participation in future studies using SkinTracker. Almost all subjects agreed or strongly agreed that SkinTracker enabled more convenient participation in skin research studies compared to an in-person format.
Discussion: To our knowledge, SkinTracker is one of the first integrated app- and web-based platforms allowing collection and management of data commonly obtained in clinical research studies. SkinTracker enables detailed, frequent capture of data that may better reflect the fluctuating course of conditions such as AD, and can be modularly customized for different skin conditions to improve dermatologic research participation and patient access.
Competing Interests: TB has received research grant funding from Novartis and Regeneron and is a principal investigator for trials sponsored by Abbvie, Castle, CorEvitas, Dermavant, Galderma, Mindera, and Pfizer. She has served as an advisor for Abbvie, Arcutis, Boehringer-Ingelheim, Bristol Myers Squibb, Janssen, Leo, Lilly, Novartis, Pfizer, Sun, and UCB. WL has received research grant funding from Abbvie, Amgen, Janssen, Leo, Novartis, Pfizer, Regeneron, and TRex Bio. AK, PD, and ND were employed by RedBlink Inc. The remaining 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.
(© 2023 Jin, Hong, Elhage, Braun, Spencer, Chung, Yeroushalmi, Hadeler, Mosca, Bartholomew, Hakimi, Davis, Thibodeaux, Wu, Kahlon, Dhaliwal, Mathes, Dhaliwal, Bhutani and Liao.)

Despite scientific and technological advances in the field of assistive technology (AT) for people with visual impairment (VI), technological designs are frequently based on a poor understanding of the physical and social context of use, resulting in devices that are less than optimal for their intended beneficiaries. To resolve this situation, user-centred approaches in the development process of AT have been widely adopted in recent years. However, there is a lack of systematization on the application of this approach. This systematic review registered in PROSPERO (CRD42022307466), assesses the application of the ISO 9241-210 human-centred design principles in allegedly "user-centred designed" AT developments for persons with VI (see Supplementary PROSPERO Protocol). The results point to a wide variation of the depth of understanding of user needs, a poor characterization of the application of the User Centred Design (UCD) approach in the initial design phases or in the early prototyping, and a vague description of user feedback and device iteration. Among the principles set out in ISO 9241-210, the application of 5.6: "the design team includes multidisciplinary skills and perspectives" is the one for which the least evidence is found. The results show there is not enough evidence to fully assess the impact of UCD in (1) promoting innovation regarding AT products and practices, and (2) Judging if AT produced following such standards is leading to better user access, wellbeing outcomes and satisfaction. To address this gap it is necessary to, first, generate better implementation of UCD in AT development and second, to strengthen evidence regarding the implementation and outcomes of using UCD for AT. To better engage with the realities of persons with VI, we propose capacity building across development teams regarding UCD, its principles and components; better planning for UCD implementation; and cross-fertilization across engineering disciplines and social and clinical science.
Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=307466 PROSPERO (CRD42022307466).
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.
(© 2023 Ortiz-Escobar, Chavarria, Schönenberger, Hurst, Stein, Mugeere and Rivas Velarde.)

Background: Lumbar puncture is an essential medical procedure whose objective is to obtain cerebrospinal fluid. Lumbar puncture is considered a complex procedure, mainly for novice residents who suffer from stress and low confidence, which may result in harm to the patient.
Methods: The LPVirSim, has been developed in four stages: i) requirements analysis through user-centred design; ii) prototyping of the virtual environment and the haptic component; iii) preliminary tests with Ph.D. students and physicians using two haptic devices (Omega.7 and Sigma.7); iv) a user study where physicians evaluated the usability and user experience.
Results: The LPVirSim integrates non-technical skills and the possibility of representing different patients for training. Usability increased from 61.76 to 68.75 in the preliminary tests to 71.43 in the user study.
Conclusions: All the results showed good usability and demonstrated that the simulator arouses interest and realistically represents a Lumbar puncture, through the force and visual feedback.
(© 2023 John Wiley & Sons Ltd.)

This design study presents an analysis and abstraction of temporal and spatial data, and workflows in the domain of hydrogeology and the design and development of an interactive visualization prototype. Developed in close collaboration with a group of hydrogeological researchers, the interface supports them in data exploration, selection of data for their numerical model calibration, and communication of findings to their industry partners. We highlight both pitfalls and learnings of the iterative design and validation process and explore the role of rapid prototyping. Some of the main lessons were that the ability to see their own data changed the engagement of skeptical users dramatically and that interactive rapid prototyping tools are thus powerful to unlock the advantage of visual analysis for novice users. Further, we observed that the process itself helped the domain scientists understand the potential and challenges of their data more than the final interface prototype.

Models of urea kinetics facilitate a mechanistic understanding of urea transfer and provide a tool for optimizing dialysis efficacy. Dual-compartment models have largely replaced single-compartment models as they are able to accommodate the urea rebound on the cessation of dialysis. Modeling the kinetics of urea and other molecular species is frequently regarded as a rarefied academic exercise with little relevance at the bedside. We demonstrate the utility of System Dynamics in creating multi-compartment models of urea kinetics by developing a dual-compartment model that is efficient, intuitive, and widely accessible to a range of practitioners. Notwithstanding its simplicity, we show that the System Dynamics model compares favorably with the performance of a more complex volume-average model in terms of calibration to clinical data and parameter estimation. Its intuitive nature, ease of development/modification, and excellent performance with real-world data may make System Dynamics an invaluable tool in widening the accessibility of hemodialysis modeling.
(© 2023. The Author(s).)

Optical sensing offers several advantages owing to its non-invasiveness and high sensitivity. The miniaturization of optical sensors will mitigate spatial and weight constraints, expanding their applications and extending the principal advantages of optical sensing to different fields, such as healthcare, Internet of Things, artificial intelligence, and other aspects of society. In this study, we present the development of a miniature optical sensor for monitoring thrombi in extracorporeal membrane oxygenation (ECMO). The sensor, based on a complementary metal-oxide semiconductor integrated circuit (CMOS-IC), also serves as a photodiode, amplifier, and light-emitting diode (LED)-mounting substrate. It is sized 3.8 × 4.8 × 0.75 mm 3 and provides reflectance spectroscopy at three wavelengths. Based on semiconductor and microelectromechanical system (MEMS) processes, the design of the sensor achieves ultra-compact millimeter size, customizability, prototyping, and scalability for mass production, facilitating the development of miniature optical sensors for a variety of applications.

Animals, Antivenins therapeutic use, Antibodies, Monoclonal therapeutic use, Snake Bites diagnosis, Snake Bites drug therapy, Crotalid Venoms therapeutic use, and Bothrops

Background: Brazil is home to a multitude of venomous snakes; perhaps the most medically relevant of which belong to the Bothrops genus. Bothrops spp. are responsible for roughly 70% of all snakebites in Brazil, and envenomings caused by their bites can be treated with three types of antivenom: bothropic antivenom, bothro-lachetic antivenom, and bothro-crotalic antivenom. The choice to administer antivenom depends on the severity of the envenoming, while the choice of antivenom depends on availability and on how certain the treating physician is that the patient was bitten by a bothropic snake. The diagnosis of a bothropic envenoming can be made based on expert identification of the dead snake or a photo thereof or based on a syndromic approach wherein the clinician examines the patient for characteristic manifestations of envenoming. This approach can be very effective but requires staff that has been trained in clinical snakebite management, which, unfortunately, far from all relevant staff has.
Results: In this article, we describe a prototype of the first lateral flow assay (LFA) capable of detecting venoms from Brazilian Bothrops spp. The monoclonal antibodies for the assay were generated using hybridoma technology and screened in sandwich enzyme-linked immunosorbent assays (ELISAs) to identify Bothrops spp.-specific antibody sandwich pairs. The prototype LFA is able to detect venom from several Bothrops spp. The LFA has a limit of detection (LoD) of 9.5 ng/mL in urine, when read with a commercial reader, and a visual LoD of approximately 25 ng/mL.
Significance: The work presented here serves as a proof of concept for a genus-specific venom detection kit that could support physicians in diagnosing Bothrops envenomings. Although further optimisation and testing is needed before the LFA can find clinical use, such a device could aid in decentralising antivenoms in the Brazilian Amazon and help ensure optimal snakebite management for even more victims of this highly neglected disease.
Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Cecilie Knudsen, Jonas A. Jürgensen, Søren H. Dam, Aleksander M. Haack, Rasmus U. W. Friis, and Andreas H. Laustsen are co-founders of VenomAid Diagnostics A/S. Jonas A. Jürgensen, Pelle D. Knudsen, and Georgina M. Ross are employed by VenomAid Diagnostics A/S. Cecilie Knudsen is an industrial PhD student at the Technical University of Denmark. Her PhD is co-sponsored by Innovation Fund Denmark and BioPorto Diagnostics A/S. Cecilie Knudsen, Jonas A. Jürgensen, Søren H. Dam, Aleksander M. Haack, Rasmus U. W. Friis, and Andreas H. Laustsen have been designated as inventors on a patent application related to the work presented here.
(Copyright © 2023 The Author(s). Published by Elsevier B.V. All rights reserved.)

Since temperature and its spatial, and temporal variations affect a wide range of physical properties of material systems, they can be used to create reconfigurable spatial structures of various types in physical and biological objects. This paper presents an experimental optical setup for creating tunable two-dimensional temperature patterns on a micrometer scale. As an example of its practical application, we have produced temperature-induced magnetization landscapes in ferrimagnetic yttrium iron garnet films and investigated them using micro-focused Brillouin light scattering spectroscopy. It is shown that, due to the temperature dependence of the magnon spectrum, spatial temperature distributions can be visualized even for microscale thermal patterns.
(© 2023 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).)

Humans, Thinking, and Pharmacy Research

Design thinking is an approach to problem solving that focuses on a solution to a problem. This systematic approach can be applied to practice-based research or implementation projects in your practice setting. It may be useful for starting new projects as well as revisiting past projects that may not have yielded meaningful results. The design-thinking process begins with identifying a problem or knowledge gap and then the steps include: (1) understanding the problem, (2) observing the problem, (3) defining the problem, (4) brainstorming possible solutions, (5) prototyping the best solution, and (6) testing the solution.

Humans, Child, United States, Medical Oncology, Surveys and Questionnaires, Awareness, Neoplasms drug therapy, and Nurses

The expanded access to clinical trials has provided more patients the opportunity to participate in novel therapeutics research. There is an increased likelihood of a patient, as a pediatric oncology clinical trial participant, to present for clinical care outside the research site, such as at an emergency room or urgent care center. A novel wearable universal serial bus device is a proposed technology to bridge potential communication gaps, pertaining to critical information such as side effects and permitted therapies, between research teams and clinical teams where investigational agents may be contraindicated to standard treatments. Fifty-five emergency and urgent care nurses across the United States were presented, via online survey without priming to the context of clinical trials or the device, a picture of a pediatric patient wearing the novel wearable device prompted to identify significant, environmental cues important for patient care. Of the 40 nurses observing the patient photo, three identified the wearable device within Situational Awareness Global Assessment Tool formatted narrative response fields. Analysis of the narrative nurse-participant responses of significant clinical findings upon initial assessment of the pediatric patient photo is described, as well as the implications for subsequent prototyping of the novel universal serial bus prototype.
(Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

The increasing interests in analog computing nowadays call for multipurpose analog computing platforms with reconfigurability. The advancement of analog computing, enabled by novel electronic elements like memristors, has shown its potential to sustain the exponential growth of computing demand in the new era of analog data deluge. Here, a platform of a memristive field-programmable analog array (memFPAA) is experimentally demonstrated with memristive devices serving as a variety of core analog elements and CMOS components as peripheral circuits. The memFPAA is reconfigured to implement a first-order band pass filter, an audio equalizer, and an acoustic mixed frequency classifier, as application examples. The memFPAA, featured with programmable analog memristors, memristive routing networks, and memristive vector-matrix multipliers, opens opportunities for fast prototyping analog designs as well as efficient analog applications in signal processing and neuromorphic computing.
(© 2022 The Authors. Advanced Materials published by Wiley-VCH GmbH.)

Humans, Light, Neuronal Plasticity, Ophthalmoscopes, Retinal Cone Photoreceptor Cells, and Retina

We aim to reprogram visual perception through an Adaptive Optics Scanning Laser Ophthalmoscope (AOSLO) Display, using a GPU renderer that rasterizes a target color image or video into cone-by-cone single-wavelength laser light pulses ("microdoses"). We imaged and tracked at ~ 2° eccentricity a 0.9° x 0.9° field of view of the retina in 840 nm. Stimulated in 543 nm, all resolved, spectrally classified cones receive microdoses of varying intensities. The renderer updates for each AOSLO frame (30 frames / sec) an underlying stimulation image buffer, encoding a desired color percept pattern that takes into account the cone locations, cone spectral sensitivity to the 543 nm stimulation light, and the corresponding color percept pixel values. Within one frame, the buffer gets pixelated strip-by-strip at 1 kHz into actual world-fixed microdose intensity values, each centered on a cone within that strip at that instant. The resulting frame of microdoses visually occupies the whole raster view. We showed multiple color percepts to a cone-classified subject, with logging data. The subject saw spatially-varying colors, e.g. a red box moving on a green canvas - these percepts validated the accuracy of the prototype. These initial prototyping experiments allude to the potential of presenting general percepts to a cone-classified subject, at cone-level accuracy in a fully programmable way. The technology allows us to probe neural plasticity and towards generation of novel percepts.

Modern technological advancements have opened avenues for innovative low-energy sources in construction, with electric field energy harvesting (EFEH) from overhead power lines serving as a prime candidate for empowering intelligent monitoring sensors and vital communication networks. This study delves into this concept, presenting a physical model of an energy harvester device. The prototype was meticulously designed, simulated, constructed, and tested, to validate its foundational mathematical model, with implications for future prototyping endeavors. The findings illustrate the potential of harnessing ample power from this device when deployed on medium-voltage (MV) overhead power lines, facilitating the monitoring of electric and meteorological parameters and their seamless communication through the Internet of Things (IoT) network. The study focused on the medium voltage applications of the harvester. Two dielectric materials were tested in the present experiments: air and polyurethane. The measurement results exhibited satisfactory alignment, particularly with the air dielectric. Nevertheless, deviations arose when employing polyurethane rubber as the dielectric, due to impurities and defects within the material. The feasibility of generating the requisite 0.84 mW output power to drive process electronics, sensors, and IoT communications was established. The novelty of this work rests in its comprehensive approach, cementing the theoretical concept through rigorous experimentation, and emphasizing its application in enhancing the efficacy of overhead power line monitoring.

LoRa technology has gained popularity as one of the most widely used standards for device interconnection due to its ability to cover long distances and energy efficiency, making it a suitable choice for various Internet of Things (IoT) monitoring and control applications. In this sense, this work presents the development of a visual support tool for creating IoT devices with LoRa and LoRaWAN connectivity. This work significantly advances the state of the art in LoRa technology by introducing a novel visual support tool tailored for creating IoT devices with LoRa and LoRaWAN connectivity. By simplifying the development process and offering compatibility with multiple hardware solutions, this research not only facilitates the integration of LoRaWAN technology within educational settings but also paves the way for rapid prototyping of IoT nodes. The incorporation of block programming for LoRa and LoRaWAN using the Arduinoblocks framework as a graphical environment enhances the capabilities of the tool, positioning it as a comprehensive solution for efficient firmware generation. In addition to the visual tool for firmware generation, multiple compatible hardware solutions enable easy, economical, and stable development, offering a comprehensive hardware and software solution. The hardware proposal is based on an ESP32 microcontroller, known for its power and low cost, in conjunction with an RFM9x module that is based on SX127x LoRa transceivers. Finally, three successfully tested use cases and a discussion are presented.

Humans, Prospective Studies, Fatigue, Educational Status, Psychiatry, and Military Personnel

Background: Military service inherently includes frequent periods of high-stress training, operational tempo, and sustained deployments to austere far-forward environments. These occupational requirements can contribute to acute and chronic sleep disruption, fatigue, and behavioral health challenges related to acute and chronic stress and disruption of team dynamics. To date, there is no centralized mobile health platform that supports self- and supervised detection, monitoring, and management of sleep and behavioral health issues in garrison and during and after deployments.
Objective: The objective of this study was to adapt a clinical decision support platform for use outside clinical settings, in garrison, and during field exercises by medics and soldiers to monitor and manage sleep and behavioral health in operational settings.
Methods: To adapt an existing clinical decision support digital health platform, we first gathered system, content, and context-related requirements for a sleep and behavioral health management system from experts. Sleep and behavioral health assessments were then adapted for prospective digital data capture. Evidence-based and operationally relevant educational and interventional modules were formatted for digital delivery. These modules addressed the management and mitigation of sleep, circadian challenges, fatigue, stress responses, and team communication. Connectivity protocols were adapted to accommodate the absence of cellular or Wi-Fi access in deployed settings. The resulting apps were then tested in garrison and during 2 separate field exercises.
Results: Based on identified requirements, 2 Android smartphone apps were adapted for self-monitoring and management for soldiers (Soldier app) and team supervision and intervention by medics (Medic app). A total of 246 soldiers, including 28 medics, received training on how to use the apps. Both apps function as expected under conditions of limited connectivity during field exercises. Areas for future technology enhancement were also identified.
Conclusions: We demonstrated the feasibility of adapting a clinical decision support platform into Android smartphone-based apps to collect, save, and synthesize sleep and behavioral health data, as well as share data using adaptive data transfer protocols when Wi-Fi or cellular data are unavailable. The AIRE (Autonomous Connectivity Independent System for Remote Environments) prototype offers a novel self-management and supervised tool to augment capabilities for prospective monitoring, detection, and intervention for emerging sleep, fatigue, and behavioral health issues that are common in military and nonmilitary high-tempo occupations (eg, submarines, long-haul flights, space stations, and oil rigs) where medical expertise is limited.
(©Anne Germain, Megan Wolfson, I Wayan Pulantara, Meredith L Wallace, Katie Nugent, George Mesias, Kristina Clarke-Walper, Phillip J Quartana, Joshua Wilk. Originally published in the Journal of Medical Internet Research (https://www.jmir.org), 28.08.2023.)

'openFrame' is a modular, low-cost, open-hardware microscopy platform that can be configured or adapted to most light microscopy techniques and is easily upgradeable or expandable to multiple modalities. The ability to freely mix and interchange both open-source and proprietary hardware components or software enables low-cost, yet research-grade instruments to be assembled and maintained. It also enables rapid prototyping of advanced or novel microscope systems. For long-term time-lapse image data acquisition, slide-scanning or high content analysis, we have developed a novel optical autofocus incorporating orthogonal cylindrical optics to provide robust single-shot closed-loop focus lock, which we have demonstrated to accommodate defocus up to ±37 μm with <200 nm accuracy, and a two-step autofocus mode which we have shown can operate with defocus up to ±68 μm. We have used this to implement automated single molecule localisation microscopy (SMLM) in a relatively low-cost openFrame-based instrument using multimode diode lasers for excitation and cooled CMOS cameras.
(© 2023 The Authors. Journal of Microscopy published by John Wiley & Sons Ltd on behalf of Royal Microscopical Society.)

In the field of bioprocess development miniaturization, parallelization and flexibility play a key role reducing costs and time. To precisely meet these requirements, additive manufacturing (3D-printing) is an ideal technology. 3D-printing enables rapid prototyping and cost-effective fabrication of individually designed devices with complex geometries on demand. For successful bioprocess development, monitoring of process-relevant parameters, such as pH, dissolved oxygen (DO), and biomass, is crucial. Online monitoring is preferred as offline sampling is time-consuming and leads to loss of information. In this study, 3D-printed cultivation vessels with optical prisms are evaluated for the use in upstream processes of different industrially relevant microorganisms and cell lines. It was shown, that the 3D-printed optically modified well (OMW) is of benefit for a wide range of biotechnologically relevant microorganisms and even for mammalian suspension cells. Evaluation tests with Escherichia coli , Bacillus subtilis , Saccharomyces cerevisiae , and Chinese hamster ovary (CHO) cells were performed, providing highly reproducible results. Growth behavior of OMW cultures was comparable to behavior of shake flask (SF) cultivations and the signal to noise ratio in online biomass measurement was shown to be reduced up to 95.8% by using the OMW. Especially the cultivation phases with low turbidity respective optical densities below 1.0 rel.AU could be monitored accurately for the first time. Furthermore, it was demonstrated that the 3D-printed optics are transferable to different well geometries and sizes, enabling efficient biomass monitoring for individual requirements with tailor-made 3D-printed cultivation vessels in small scale.
Competing Interests: The authors declare no conflict of interest.
(© 2023 The Authors. Engineering in Life Sciences published by Wiley‐VCH GmbH.)

Fabrication of patterned boron-doped diamond (BDD) in an inexpensive and straightforward way is required for a variety of practical applications, including the development of BDD-based electrochemical sensors. This work describes a simplified and novel bottom-up fabrication approach for BDD-based three-electrode sensor chips utilizing direct inkjet printing of diamond nanoparticles on silicon-based substrates. The whole seeding process, accomplished by a commercial research inkjet printer with piezo-driven drop-on-demand printheads, was systematically examined. Optimized and continuous inkjet-printed features were obtained with glycerol-based diamond ink (0.4% vol/wt), silicon substrates pretreated by exposure to oxygen plasma and subsequently to air, and applying a dot density of 750 drops (volume 9 pL) per inch. Next, the dried micropatterned substrate was subjected to a chemical vapor deposition step to grow uniform thin-film BDD, which satisfied the function of both working and counter electrodes. Silver was inkjet-printed to complete the sensor chip with a reference electrode. Scanning electron micrographs showed a closed BDD layer with a typical polycrystalline structure and sharp and well-defined edges. Very good homogeneity in diamond layer composition and a high boron content (∼2 × 10 21 atoms cm -3 ) was confirmed by Raman spectroscopy. Important electrochemical characteristics, including the width of the potential window (2.5 V) and double-layer capacitance (27 μF cm -2 ), were evaluated by cyclic voltammetry. Fast electron transfer kinetics was recognized for the [Ru(NH 3 ) 6 ] 3+/2+ redox marker due to the high doping level, while somewhat hindered kinetics was observed for the surface-sensitive [Fe(CN) 6 ] 3-/4- probe. Furthermore, the ability to electrochemically detect organic compounds of different structural motifs, such as glucose, ascorbic acid, uric acid, tyrosine, and dopamine, was successfully verified and compared with commercially available screen-printed BDD electrodes. The newly developed chip-based manufacture method enables the rapid prototyping of different small-scale electrode designs and BDD microstructures, which can lead to enhanced sensor performance with capability of repeated use.

Lab-On-A-Chip Devices, Microfluidics, and Nucleic Acid Amplification Techniques methods

In this work, we demonstrate an inexpensive method of prototyping microfluidics using a desktop injection molding machine. A centrifugal microfluidic device with a novel central filling mechanism was developed to demonstrate the technique. We overcame the limitations of desktop machines in replicating microfluidic features by variotherm heating and cooling the mold between 50 °C and 110 °C within two minutes. Variotherm heating enabled good replication of microfeatures, with a coefficient of variation averaging only 3.6% attained for the measured widths of 100 μm wide molded channels. Using this methodology, we produced functional polystyrene centrifugal microfluidic chips, capable of aliquoting fluids into 5.0 μL reaction chambers with 97.5% accuracy. We performed allele-specific loop-mediated isothermal amplification (AS-LAMP) reactions for genotyping CYP2C19 alleles on these chips. Readouts were generated using optical pH sensors integrated onto chips, by drop-casting sensor precursor solutions into reaction chambers before final chip assembly. Positive reactions could be discerned by decreases in pH sensor fluorescence, thresholded against negative control reactions lacking the primers for nucleic acid amplification and with time-to-results averaging 38 minutes. Variotherm desktop injection molding can enable researchers to prototype microfluidic devices more cost-effectively, in an iterative fashion, due to reduced costs of smaller, in-house molds. Designs prototyped this way can be directly translated to mass production, enhancing their commercialization potential and positive impacts.

The osseous tissue can be classified as a nanocomposite that encompasses a complex interweaving of organic and inorganic matrices. This intricate amalgamation consists of a collagen component and a mineral phase that are intricately arranged to form elaborate and perforated configurations. Hydroxyapatite, whether synthesized artificially or obtained from natural sources, has garnered considerable attention as a composite material in the field of bone tissue engineering due to its striking resemblance to bone in terms of structure and characteristics. Hydroxyapatite (HA) constitutes the predominant ceramic biomaterial for biomedical applications due to its ability to replicate the mineral composition of vertebrate bone. Nonetheless, it is noteworthy that the present biomimetic substance exhibits unfavorable mechanical characteristics, characterized by insufficient tensile and compressive strength, thus rendering it unsuitable for effective employment in the field of bone tissue engineering. Due to its beneficial attributes, hydroxyapatite (HA) is frequently employed in conjunction with various polymers and crosslinkers as composites to enhance mechanical properties and overall efficacy of implantable biomaterials engineered. The restoration of skeletal defects through the use of customized replacements is an effective way to replace damaged or lost bone structures. This method not only restores the bones' original functions but also reinstates their initial aesthetic appearance. The utilization of hydroxyapatite-polymer composites within 3D-printed grafts necessitates meticulous optimization of both mechanical and biological properties, in order to ensure their suitability for employment in medical devices. The utilization of 3D-printing technology represents an innovative approach in the manufacturing of HA-based scaffolds, which offers advantageous prospects for personalized bone regeneration. The expeditious prototyping method, with emphasis on the application of 3D printing, presents a viable approach in the development of bespoke prosthetic implants, grounded on healthcare data sets. 4D printing approach is an evolved form of 3D printing that utilizes programmable materials capable of altering the intended shape of printed structures, contingent upon single or dual stimulating factors. These factors include aspects such as pH level, temperature, humidity, crosslinking degree, and leaching factors.
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 Authors.)

Three-dimensional printing technology has been used for more than three decades in many industries, including the automotive and aerospace industries. So far, the use of this technology in medicine has been limited only to 3D printing of anatomical models for educational and training purposes, which is due to the insufficient functional properties of the materials used in the process. Only recent advances in the development of innovative materials have resulted in the flourishing of the use of 3D printing in medicine and pharmacy. Currently, additive manufacturing technology is widely used in clinical fields. Rapid development can be observed in the design of implants and prostheses, the creation of biomedical models tailored to the needs of the patient and the bioprinting of tissues and living scaffolds for regenerative medicine. The purpose of this review is to characterize the most popular 3D printing techniques.

The increasing demand for seafood is responsible for many environmental impacts, especially caused by aquaculture. Shrimp accounts for a substantial part of seafood production and therefore also for negative effects associated with it. This work aimed to develop a mushroom-based shrimp analogue with a texture similar to shrimp using the fruiting bodies of pink oyster mushroom ( Pleurotus djamor ) and lion's mane ( Hericium erinaceus ). Three flushes of pink oyster mushrooms and a first flush of lion's mane mushroom were analysed regarding their nutritional composition and whether they are suitable shrimp alternatives. The two mushrooms are rich in proteins (∼32% and ∼26% w/w for the first flush of pink oyster and lion's mane, respectively). The protein content of pink oyster mushroom decreased and the dietary fibre content increased across the different flushes. The antioxidants in the mushrooms were extracted using different methods, whereby aqueous extracts mostly excelled in terms of antioxidant activity. Hydrolysis confirmed the presence of conjugated p -coumaric acid in both mushrooms and possibly conjugated caffeic acid in pink oyster. Texture analysis results of the prototypes were close to the values of fried shrimp. However, although the sensory qualities of the final prototypes were perceived as similar to shrimp, further improvements in the recipe are necessary to make the prototypes indistinguishable from shrimp.
Competing Interests: None.
(© 2023 The Author(s).)

Three-dimensional (3D) printing, alternatively known as additive manufacturing, is a transformative technology enabling precise, customized, and efficient manufacturing of components with complex structures. It revolutionizes traditional processes, allowing rapid prototyping, cost-effective production, and intricate designs. The 3D printed graphene-based materials combine graphene's exceptional properties with additive manufacturing's versatility, offering precise control over intricate structures with enhanced functionalities. To gain comprehensive insights into the development of 3D printed graphene and graphene/polymer composites, this review delves into their intricate fabrication methods, unique structural attributes, and multifaceted applications across various domains. Recent advances in printable materials, apparatus characteristics, and printed structures of typical 3D printing techniques for graphene and graphene/polymer composites are addressed, including extrusion methods (direct ink writing and fused deposition modeling), photopolymerization strategies (stereolithography and digital light processing) and powder-based techniques. Multifunctional applications in energy storage, physical sensor, stretchable conductor, electromagnetic interference shielding and wave absorption, as well as bio-applications are highlighted. Despite significant advancements in 3D printed graphene and its polymer composites, innovative studies are still necessary to fully unlock their inherent capabilities.

In the laser sintering (LS) printing process, a printed part is formed by sintering layer-by-layer on the powder bed. Thus, it is necessary to consider the dimensional accuracy of the laser-sintered powder bed as an important evaluation index. In this paper, a generalized powder bed-size accuracy compensation model is proposed for non-crystalline thermoplastic polymer materials. Taking polyethersulfone (PES) material as an example, the main factors influencing powder bed dimensional accuracy during LS printing are modeled and analyzed experimentally in this study, including four important factors: laser reference deviation, temperature deviation, density deviation, and secondary sintering deviation. In this study, CX_A200 LS equipment is used for prototyping and verification, a 3D scanning method is used to measure the printed parts, and the measurement results are digitally compared and analyzed. On this basis, the relationship of each influencing factor in the proposed compensation model is determined experimentally, and the experimental results demonstrate that the proposed compensation model is approximately 95% effective in terms of correcting the deviation of powder bed dimensional accuracy.

Animals, Staining and Labeling, In Situ Hybridization, Antibodies, Zebrafish, and Embryo, Nonmammalian metabolism

Whole mount zebrafish antibody staining (ABS) is a common staining technique used to localize protein information in a zebrafish embryo or larva. Like most biological assays, the whole mount zebrafish ABS is still largely conducted manually through labor intensive and time-consuming steps which affect both consistency and throughput of the assay. In this work, we develop a milli fluidic device that can automatically trap and immobilize the fixed chorion-less zebrafish embryos for the whole mount ABS. With just a single loading step, the zebrafish embryos can be trapped by the milli fluidic device through a chaotic hydrodynamic trapping process. Moreover, a consistent body orientation (i.e., head point inward) for the trapped zebrafish embryos can be achieved without additional orientation adjustment device. Furthermore, we employed a consumer-grade SLA 3D printer assisted method for device prototyping which is ideal for labs with limited budgets. Notably, the milli fluidic device has enabled the optimization and successful implementation of whole mount zebrafish Caspase-3 ABS. We demonstrated our device can accelerate the overall procedure by reducing at least 50% of washing time in the standard well-plate-based manual procedure. Also, the consistency is improved, and manual steps are reduced using the milli fluidic device. This work fills the gap in the milli fluidic application for whole mount zebrafish immunohistochemistry. We hope the device can be accepted by the zebrafish community and be used for other types of whole mount zebrafish ABS procedures or expanded to more complicated in situ hybridization (ISH) procedure.
(© 2023. The Author(s).)

The brain-storm of designing low-cost and commercialized eutectic electrolytes for zinc (Zn)-based electrochemical energy storage (ZEES) remains unresolved and attractive, especially when implementing it at low temperatures. Here, we report an appealing layout of advancing chlorine-functionalized eutectic (Cl-FE) electrolytes via exploiting Cl anion-induced eutectic interaction with Zn acetate solutions. This novel eutectic liquid shows high affinity to collaborate with 1,3-dioxolane (DOL) and is prone to constitute Cl-FE/DOL-based electrolytes with a unique inner/outer eutectic solvation sheath for the better regulation of Zn-solvating neighboring and reconstruction of H-bonding. The side reactions are effectively restricted on Zn anodes and a high Coulombic efficiency of 99.5 % can be achieved over 1000 cycles at -20 °C with Zn//Cu setups. By prototyping scale-up Zn-ion pouch cells using the optimal eutectic liquid of 3ZnOAc 1.2 Cl 1.8 -DOL, we obtain improved electrochemical properties at -20 °C with a high capacitance of 203.9 F g -1 at 0.02 A g -1 in a range of 0.20-1.90 V and long-term cycling ability with 95.3 % capacitance retention at 0.2 A g -1 over 3,000 cycles. Overall, the proposal of ideal Cl-FE/DOL-based electrolytes guides the design of sub-zero and endurable aqueous ZEES devices and beyond.
(© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Background: Numerous studies describe the popularity and usefulness of parenting programs. In particular, parenting programs are generally viewed as effective for supporting parents' mental well-being during key transition periods. However, the evidence base for fathers is limited owing to their lack of involvement in parenting programs and scarcity of tailored support.
Objective: This paper aimed to describe the co-design process for a universal digital intervention for fathers (fatherli) and the outline of a logic model with its expected outcomes.
Methods: Following established guidelines for co-designing and developing complex interventions, we conducted a nonsystematic review of the available literature to gather key information, developed market surveys to assess fathers' needs and interests, consulted with key stakeholders to obtain expert opinions, and engaged in a rapid iterative prototyping process with app developers. Each step was summarized, and the information was collated and integrated to inform a logic model and the features of the resulting intervention.
Results: The steps in the co-design process confirmed a need for and interest in a digital intervention for fathers. In response to this finding, fatherli was developed, consisting of 5 key features: a discussion forum for anyone to post information about various topics (the forum), a socializing platform for fathers to create and engage with others in small groups about topics or points of shared interest (dad hub), a tool for fathers to find other fathers with shared interests or within the same geographic location (dad finder), a resource for fathers to access up-to-date information about topics that interest them (dad wiki), and a portal to book sessions with coaches who specialize in different topics (dad coaching space). The evidence-based logic model proposes that if fatherli is successfully implemented, important outcomes such as increased parental efficacy and mental health help-seeking behaviors may be observed.
Conclusions: We documented the co-design and development process of fatherli, which confirmed that it is possible to use input from end users and experts, integrated with theory and research evidence, to create suitable digital well-being interventions for fathers. In general, the key findings suggest that an app that facilitates connection, communication, and psychoeducation may appeal to fathers. Further studies will now focus on acceptability, feasibility, and effectiveness. Feedback gathered during pilot-testing will inform any further developments in the app to increase its applicability to fathers and its usability.
(©Shaun Liverpool, Mia Eisenstadt, Aoife Mulligan Smith, Sofia Kozhevnikova. Originally published in JMIR Formative Research (https://formative.jmir.org), 14.08.2023.)

Acoustic hologram lenses were typically produced by high-resolution 3D printing methods, such as stereolithography (SLA) printing. However, SLA printing of thin, plate-shaped lens structures has major limitations including vulnerability to deformation during photo-curing and limited control of acoustic impedance. To overcome these limitations, we demonstrated a nanoparticle epoxy composite (NPEC) molding technique, and we tested its feasibility for acoustic hologram lens fabrication. The characterized acoustic impedance of the 22.5% NPEC was 4.64 MRayl which is 55% higher than the clear photopolymer (2.99 MRayl) used by SLA. Simulations demonstrated that the improved pressure transmission by the higher acoustic impedance of the NPEC resulted in 21% higher pressure amplitude in the region of interest (ROI, -6 dB pressure amplitude pixels) than the photopolymer. This improvement was experimentally demonstrated after prototyping NPEC lenses through a molding process. The NPEC lens showed no significant deformation and 72% lower thickness profile errors than the photopolymer which otherwise experienced deformed edges due to thermal bending. Beam mapping results using the NPEC lens validated the predicted improvement, demonstrating 24% increased pressure amplitude on average and 10% improved structural similarity with the simulated pressure pattern compared to the photopolymer lens. This method can be used for acoustic hologram lens applications with improved pressure output and accurate pressure field formation.

Binder jetting is a highly productive additive manufacturing (AM) method for porous parts. Due to its cost-effectiveness, it is used for large components and quantities ranging from prototyping to series production. Post-processing steps like sintering or infiltration are common in several applications to achieve high density and strength. This work investigates how 3D-printed sand molds can be infiltrated with epoxy resins without vacuum assistance to produce high-strength molds for thermoforming applications. Specimens 3D-printed from different sand types are infiltrated with resins of different viscosity and analyzed for infiltration velocity and depth. The infiltration velocities corresponded well with the correlation described in Washburn's equation: The resins' viscosities and the saturation level were decisive. Amongst the investigated sand types commonly used in foundries, sand type GS19 was found most suitable for infiltration. However, the sand type proved to be a less relevant influencing factor than the resins' viscosities and quantities applied. Infiltration of topology-optimized 3D-printed sand tools up to a wall thickness of 20 mm for thermoforming applications was found to be feasible.

The application of three-dimensional printing technology in the medical field has great potential for bone defect repair, especially personalized and biological repair. As a green manufacturing process that does not involve liquefication through heating, low-temperature deposition manufacturing (LDM) is a promising type of rapid prototyping manufacturing and has been widely used to fabricate scaffolds in bone tissue engineering. The scaffolds fabricated by LDM have a multi-scale controllable pore structure and interconnected micropores, which are beneficial for the repair of bone defects. At the same time, different types of cells or bioactive factor can be integrated into three-dimensional structural scaffolds through LDM. Herein, we introduced LDM technology and summarize its applications in bone tissue engineering. We divide the scaffolds into four categories according to the skeleton materials and discuss the performance and limitations of the scaffolds. The ideas presented in this review have prospects in the development and application of LDM scaffolds.
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 Sun, Wang, Huang, Liu, Zhang, Zhang, Wang and Li.)

Stereolithography, Microtechnology, Lab-On-A-Chip Devices, Microphysiological Systems, and Printing, Three-Dimensional

Organs-on-a-chip, or OoCs, are microfluidic tissue culture devices with micro-scaled architectures that repeatedly achieve biomimicry of biological phenomena. They are well positioned to become the primary pre-clinical testing modality as they possess high translational value. Current methods of fabrication have facilitated the development of many custom OoCs that have generated promising results. However, the reliance on microfabrication and soft lithographic fabrication techniques has limited their prototyping turnover rate and scalability. Additive manufacturing, known commonly as 3D printing, shows promise to expedite this prototyping process, while also making fabrication easier and more reproducible. We briefly introduce common 3D printing modalities before identifying two sub-types of vat photopolymerization - stereolithography (SLA) and digital light processing (DLP) - as the most advantageous fabrication methods for the future of OoC development. We then outline the motivations for shifting to 3D printing, the requirements for 3D printed OoCs to be competitive with the current state of the art, and several considerations for achieving successful 3D printed OoC devices touching on design and fabrication techniques, including a survey of commercial and custom 3D printers and resins. In all, we aim to form a guide for the end-user to facilitate the in-house generation of 3D printed OoCs, along with the future translation of these important devices.

Advances in the instrumentation and materials for photopolymerization 3D printing aided the use of this powerful technique in the fabrication of microfluidic devices. The costs of printers and supplies have been reduced to the point where this technique becomes attractive for prototyping microfluidic systems with good resolution. With all the development of multi-material 3D printers, most of the microfluidic devices prepared by photopolymerization 3D printing are based on a single substrate material. We developed a digital light processing multi-material 3D printer where two or more resins can be used to prepare complex objects and functional microfluidic devices. The printer is based on a vat inclination system and embedded peristaltic pumps that allow the injection and removal of resins and cleaning step between material changes. Although we have built the whole system, the modification can be incorporated into commercially available printers. Using a high-resolution projector, microfluidic channels as narrow as 43 μm were obtained. We demonstrate the printing of multi-material objects containing flexible, rigid, water-soluble, fluorescent, phosphorescent, and conductive (containing PEDOT or copper nanoparticles) resins. An example of a microfluidic chip containing electrodes for electrochemical detection is also presented.

The transfer from batch to flow chemistry is often based on commercial microfluidic equipment, such as costly complete reactor systems, which cannot be easily tailored to specific requirements of technologies such as DNA-encoded library technology (DELT), in particular for increasingly important photochemical reactions. Customized photoreactor concepts using rapid prototyping technology offer a modular, flexible, and affordable design that allows for adaptation to various applications. In order to validate the prototype reactors, a photochemical pinacol coupling reaction at 368 nm was conducted to demonstrate the transfer from batch to flow chemistry. The conversion rates were optimized by adapting the design parameters of the microfluidic flow photoreactor module. Subsequently, the photoreactor module has been extended to an application with DNA-tagged substrates by switching to LEDs with a wavelength of 454 nm. The successful recovery of DNA confirmed the feasibility of the modular-designed flow photo reactor. This collaborative approach holds enormous potential to drive the development of DELT and flow equipment design.
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 Dinter, Willems, Nissalk, Hastürk, Brunschweiger and Kockmann.)

Objective: To describe the Cleft Recurrence Risk (Cleft RR) App, designed to be used on genetic counseling for cleft lip and/ or palate.
Design: A validation study, single cohort.
Setting: Tertiary care children's Hospital.
Patients, Participants: The manual obtained the results of 100 cases undergoing genetic counseling at the cleft lip and palate treatment center.
Interventions: The application for genetic counseling for cleft lip and/ or palate is designed to calculate quickly the recurrence risk considering the ancestry, cleft type, sex, and family history and thus encourage the implementation of genetic counseling in cleft lip and palate centers around the world.
Main Outcome Measure(s): The data were submitted to the Bland-Altman statistics.
Results: After defining parameters the application development follows the steps: development, prototyping, and documentation. The validation of the calculated data was performed by comparing the results of 100 cases undergoing genetic counseling at the cleft lip and palate treatment center obtained by the manual method with the results obtained by the mobile app method; the data were submitted to the Bland-Altman statistics and a high concordance was found.
Conclusions: The mobile app for use by healthcare professionals proved to be simple to use, easy to apply, and provided accurate results. Cleft Recurrence Risk is an application for smartphones developed for genetic counseling in cleft lip and palate, supplementary use by health professionals, and should not replace professional performance.

This study proposes a design approach and the development of a low-power planar biped robot named YU-Bibot. The kinematic structure of the robot consists of six independently driven axes, and it weighs approximately 20 kg. Based on biomimetics, the robot dimensions were selected as the average anthropomorphic dimensions of the human lower extremities. The optimization of the mechanical design and actuator selection of the robot was based on the results of parametric simulations. The natural human walking gait was mimicked as a walking pattern in these simulations. As a result of the optimization, a low power-to-weight ratio of 30 W/kg was obtained. The drive system of the robot joints consists of servo-controlled brushless DC motors with reduction gears and additional bevel gears at the knee and ankle joints. The robot features spring-supported knee and ankle joints that counteract the robot's weight and compensate for the backlash present in these joints. The robot is constrained to move only in the sagittal plane by using a lateral support structure. The robot's feet are equipped with low-cost, force-sensitive resistor (FSR)-type sensors for monitoring ground contact and zero-moment point (ZMP) criterion. The experimental results indicate that the proposed robot mechanism can follow the posture commands accurately and demonstrate locomotion at moderate stability. The proposed parametric natural gait simulation-based design approach and the resulting biped robot design with a low power/weight ratio are the main contributions of this study.

Microfluidics, Polymers, Lipids chemistry, Nanoparticles chemistry, and Liquid Crystals chemistry

Soft-matter nanoparticles are of great interest for their applications in biotechnology, therapeutic delivery, and in vivo imaging. Underpinning this is their biocompatibility, potential for selective targeting, attractive pharmacokinetic properties, and amenability to downstream functionalisation. Morphological diversity inherent to soft-matter particles can give rise to enhanced functionality. However, this diversity remains untapped in clinical and industrial settings, and only the simplest of particle architectures [spherical lipid vesicles and lipid/polymer nanoparticles (LNPs)] have been routinely exploited. This is partially due to a lack of appropriate methods for their synthesis. To address this, we have designed a scalable microfluidic hydrodynamic focusing (MHF) technology for the controllable, rapid, and continuous production of lyotropic liquid crystalline (LLC) nanoparticles (both cubosomes and hexosomes), colloidal dispersions of higher-order lipid assemblies with intricate internal structures of 3-D and 2-D symmetry. These particles have been proposed as the next generation of soft-matter nano-carriers, with unique fusogenic and physical properties. Crucially, unlike alternative approaches, our microfluidic method gives control over LLC size, a feature we go on to exploit in a fusogenic study with model cell membranes, where a dependency of fusion on particle diameter is evident. We believe our platform has the potential to serve as a tool for future studies involving non-lamellar soft nanoparticles, and anticipate it allowing for the rapid prototyping of LLC particles of diverse functionality, paving the way toward their eventual wide uptake at an industrial level.
(© 2023. Springer Nature Limited.)

Background: When considering the policing environment of 2022, many roles previously in the domain of warranted officers (police officer) are now performed by nonwarranted police staff equivalents. These police staff roles have expanded rapidly into other areas such as investigations, custody, and contact management, which were traditionally seen as police officer functions and put staff under some of the same stresses as police officers. A UK police force requested help in investigating technologies that could be used to improve health and well-being for both officers and staff.
Objective: The aim of this study was to create a health and well-being app for police officers and staff, which considered the unique requirements of the users throughout the designing, building, prototyping, and testing stages.
Methods: This study involved quantitative approaches (demographic web-based survey questions and the System Usability Scale) and qualitative approaches (open web-based survey questions and semistructured interviews). Unsupervised usability testing of a prototype app was undertaken by members (N=48) of the commissioning client using their smartphones. After completing a preregistration application for screening purposes, participants downloaded a trial version of the app. Then, they completed a web-based questionnaire after testing the app for 10 days. A subsample of participants (9/48, 19%) was interviewed. Deductive thematic analysis was undertaken to identify key themes and subthemes.
Results: Data collected during usability testing concerned the 6 domains of the app-food and diet, activity, fluid intake, sleep, good mental health, and financial well-being-and informed the creation of improved design during prototyping. Some usability and design issues and suggestions for improvements were also addressed and implemented-including shift management and catch-up cards-during this cycle of development.
Conclusions: This study highlights the importance of coparticipation with officers and staff across the entire development cycle, to coproduce a human-centered design methodology to enable the development of a considered and user-centered solution. It demonstrates the need for producing a multifunctional tool rather than focusing purely on an individual element for this user group. It also highlights how linking and being able to track optional, personalized elements of health data against one another, cross-referenced to individual shift patterns, might help to inform and provide users with a chance for reflection and therefore influence behavior change.
(©Richa Mehra, Andy Pulman, Huseyin Dogan, Jane Murphy, Fiona Bitters. Originally published in JMIR Human Factors (https://humanfactors.jmir.org), 04.08.2023.)

Laserjet printing is a kind of facile and digital do-it-yourself strategies, which is of importance to fabricate inexpensive paper-based microfluidic devices. However, the printed hydrophobic barrier is not hydrophobic enough due to the weak hydrophobicity and requires subsequent heating, which can lead to the pyrolysis of cellulose in the paper and influence the detection results. Here, for the first time, we report a kind of functional toner including toner and polydopamine (PDA) nanocapsules which contains oleic acid modified ferric tetroxide (OA-Fe 3 O 4 ) and octadecylamine (ODA), which is suitable for printing with desired shapes and sizes to lead to formation of superhydrophobic barriers. Moreover, patterns printed with functional toner have good stability, including resistance to moisture, ultraviolet (UV) and bending. Finally, a proof-of-concept of metal and nitrite ions testing is demonstrated using colorimetric analysis, and the results show that the printed devices successfully perform instant detection of ions. The developed functional toner offers easy fabrication, cost-effectiveness and mass production of paper-based devices. In general, this strategy provides a new idea and technical support for the rapid prototyping of microfluidic paper-based analytical devices (μPADs) using laserjet printing.
(© 2023. Springer Nature Limited.)

The production of activated carbon (AC) from lignocellulosic biomass through chemical activation is gaining global attention due to its scalability, economic viability, and environmental advantages. Chemical activation offers several benefits, including energy efficiency, reduced carbonization time, and lower temperature requirements. In this study, potassium hydroxide (KOH) was employed for chemical activation, resulting in activated carbon with a high specific surface area of ~3050 m 2 /g. The structural analysis revealed the presence of graphitized carbon in the activated carbon matrix, accounting for over 15%. The X-ray diffraction (XRD) technique was employed to investigate the activated carbon derived from rice husk (RH). The potential applications of activated carbon obtained from rice husks through chemical activation were explored, including its use for heavy metal removal, elimination of organic pollutants, and as an active material in hybrid energy storage devices. Furthermore, a scaling methodology for the production of activated carbon was proposed, facilitating its industrial implementation.

Futuristic microfluidics will require alternative ways to extend its potential in vast areas by integrating various facets such as automation of different subsystems, multiplexing, incorporation of cyber-physical capabilities, and rapid prototyping. On the rapid prototyping aspect, for the last decade, additive manufacturing (AM) or 3D printing (3DP) has advanced to become an alternative fabrication process for microfluidic devices, enabling industry-level abilities towards mass production. In this context, for the first time, this work demonstrates the fabrication of monolithic multilayer microfluidic devices (MMMD) from planar orientation (1 layer) to nonplanar (4 layers) monolithic microchannels. The developed MMM device was impeccable for synthesizing highly potentialized silver nanoparticles (AgNPs) in <1 s. Moreover, the transport of chemical species with laminar flow simulations was performed on the process along with the thorough characterizations of produced AgNPs, finding the mean AgNPs particle size of around 35 nm without any post-processing requirements. The well-known catalytic activity of AgNPs was leveraged to enhance weak chemiluminescence (CL) sensing signals by >1300 %, increasing CL sensitivity. Further, machine learning (ML) predictive models encouraged to obtain the experimental parameters without human intervention iterations for target-specific applications. The proposed methodology finds the potential to save resources, time, and enables automation with rapid prototyping, providing possibilities for mass fabrications.
Competing Interests: Declaration of competing interest An Indian patent was filed by Sanket Goel and Pavar Sai Kumar with the patent number: 202311012926. Further, authors declare no conflict of Interests.
(Copyright © 2023 Elsevier B.V. All rights reserved.)

The main objective of subsea mechanical dispersion (SSMD) is to reduce the oil droplet sizes from a subsea oil release, thereby influencing the fate and behaviour of the released oil in the marine environment. Subsea water jetting was identified as a promising method for SSMD and imply that a water jet is used to reduce the particle size of the oil droplets initially formed from the subsea release. This paper presents the main findings from a study including small-scale testing in a pressurised tank, via laboratory basin testing, to large-scale outdoor basin testing. The effectiveness of SSMD increases with the scale of the experiments. From a five-fold reduction in droplet sizes for small-scale experiments to more than ten-fold for large-scale experiments. The technology is ready for full-scale prototyping and field testing. Large-scale experiments performed at Ohmsett indicate that SSMD could be comparable to subsea dispersant injection (SSDI) in reducing oil droplet sizes.
Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: The first author (Brandvik) has an Adjunct Professor position at the Norwegian University of Science and Technology (NTNU). This is a 20 % position, and it is financed by a cooperation between the NTNU and a major energy company in Norway (Equinor AS). The program is called Akademia-avtalen. However, this cooperation does not give the industry any influence on candidates holding an adjunct position funded by this program. They are employed by NTNU through an ordinary announcement/evaluation process. The industry has also no influence on the academic activity or production of the adjunct professors.
(Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Humans, Gait physiology, Ankle, Walking physiology, Ankle Joint physiology, Biomechanical Phenomena, and Foot Orthoses

To maximize effects of dorsal leaf ankle foot orthoses (AFOs) on gait in people with bilateral plantarflexor weakness, the AFO properties should be matched to the individual. However, how AFO properties interact regarding their effect on gait function is unknown. We studied the interaction of AFO bending stiffness with neutral angle and footplate stiffness on the effect of bending stiffness on walking energy cost, gait kinematics and kinetics in people with plantarflexor weakness by employing predictive simulations. Our simulation framework consisted of a planar 11 degrees of freedom model, containing 11 muscles activated by a reflex-based neuromuscular controller. The controller was optimized by a comprehensive cost function, predominantly minimizing walking energy cost. The AFO bending and footplate stiffness were modelled as torsional springs around the ankle and metatarsal joint. The neutral angle of the AFO was defined as the angle in the sagittal plane at which the moment of the ankle torsional spring was zero. Simulations without AFO and with AFO for 9 bending stiffnesses (0-14 Nm/degree), 3 neutral angles (0-3-6 degrees dorsiflexion) and 3 footplate stiffnesses (0-0.5-2.0 Nm/degree) were performed. When changing neutral angle towards dorsiflexion, a higher AFO bending stiffness minimized energy cost of walking and normalized joint kinematics and kinetics. Footplate stiffness mainly affected MTP joint kinematics and kinetics, while no systematic and only marginal effects on energy cost were found. In conclusion, the interaction of the AFO bending stiffness and neutral angle in bilateral plantarflexor weakness, suggests that these should both be considered together when matching AFO properties to the individual patient.
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 Ltd.. All rights reserved.)

Humans, Commerce, Computer-Aided Design, Surgery, Plastic, Plastic Surgery Procedures, and Surgeons

Abstract: Three-dimensional (3D) printing continues to revolutionize the field of plastic surgery, allowing surgeons to adapt to the needs of individual patients and innovate, plan, or refine operative techniques. The utility of this manufacturing modality spans from surgical planning, medical education, and effective patient communication to tissue engineering and device prototyping and has valuable implications in every facet of plastic surgery. Three-dimensional printing is more accessible than ever to the surgical community, regardless of previous background in engineering or biotechnology. As such, the onus falls on the surgeon-innovator to have a functional understanding of the fundamental pipeline and processes in actualizing such innovation. We review the broad range of reported uses for 3D printing in plastic surgery, the process from conceptualization to production, and the considerations a physician must make when using 3D printing for clinical applications. We additionally discuss the role of computer-assisted design and manufacturing and virtual and augmented reality, as well as the ability to digitally modify devices using this software. Finally, a discussion of 3D printing logistics, printer types, and materials is included. With innovation and problem solving comprising key tenets of plastic surgery, 3D printing can be a vital tool in the surgeon's intellectual and digital arsenal to span the gap between concept and reality.
Competing Interests: Conflicts of interest and sources of funding: none declared.
(Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

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.)

Printing, Three-Dimensional, Polymers, Phenylalanine, Amino Acids, and Acrylamide

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.)

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.)

Humans, Child, Female, Adult, Adolescent, Goals, Parents, Surveys and Questionnaires, Urology, and Spinal Dysraphism complications

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.)

Advances in 2-photon lithography have enabled in-lab production of sub-micron resolution and millimeter scale 3D optical components. The potential complex geometries are well suited to rapid prototyping and production of waveguide structures, interconnects, and waveguide directional couplers, furthering future development and miniaturization of waveguide-based imaging technologies. System alignment is inherent to the 2-photon process, obviating the need for manual assembly and allowing precise micron scale waveguide geometries not possible in traditional fused fiber coupler fabrication. Here we present the use of 2-photon lithography for direct printing of multi-mode waveguide couplers with air cladding and single mode waveguide couplers with uncured liquid photoresin cladding. Experimental results show reproducible coupling which can be modified by selected design parameters.

The present study was conducted to manipulate various biomaterials to find potential hydrogel formulations through three-dimensional (3D) bioprinting fabrication for tissue repair, reconstruction, or regeneration. The hydrogels were prepared using sodium alginate and gelatin combined with different concentrations of Pluronic F127 (6% (3 g), 8% (4 g), and 10% (5 g)) and were marked as AGF-6%, AGF-8%, and AGF-10%, respectively. The properties of the hydrogels were investigated using a contact angle goniometer, rheometer, and 3D bioprinter. In addition, the osteoblast-like cell line (MG-63) was used to evaluate the cell viability including hydrogels before and after 3D bioprinting. It was found that the ratio of contact angle was lowest at AGF-6%, and the rheological results were higher for all samples of AGF-6%, AGF-8%, and AGF-10% compared with the control sample. The printability indicated that the AGF-6% hydrogel possessed great potential in creating a cell scaffold with shape integrity. Moreover, the live/dead assay also presented the highest numbers of live cells before printing compared with after printing. However, the number of live cells on day 7 was higher than on day 1 before and after printing (** p < 0.01). Therefore, the combination of AGF-6% could be developed as a biofunctional hydrogel formulation for potential tissue regeneration applications.

Engineering microfluidic devices relies on the ability to manufacture sub-100 micrometer fluidic channels. Conventional lithographic methods provide high resolution but require costly exposure tools and outsourcing of masks, which extends the turnaround time to several days. The desire to accelerate design/test cycles has motivated the rapid prototyping of microfluidic channels; however, many of these methods (e.g., laser cutters, craft cutters, fused deposition modeling) have feature sizes of several hundred microns or more. In this paper, we describe a 1-day process for fabricating sub-100 µm channels, leveraging a low-cost (USD 600) 8K digital light projection (DLP) 3D resin printer. The soft lithography process includes mold printing, post-treatment, and casting polydimethylsiloxane (PDMS) elastomer. The process can produce microchannels with 44 µm lateral resolution and 25 µm height, posts as small as 400 µm, aspect ratio up to 7, structures with varying z-height, integrated reservoirs for fluidic connections, and a built-in tray for casting. We discuss strategies to obtain reliable structures, prevent mold warpage, facilitate curing and removal of PDMS during molding, and recycle the solvents used in the process. To our knowledge, this is the first low-cost 3D printer that prints extruded structures that can mold sub-100 µm channels, providing a balance between resolution, turnaround time, and cost (~USD 5 for a 2 × 5 × 0.5 cm 3 chip) that will be attractive for many microfluidics labs.

Background: Parenting programs have proven effective in improving the behavior of children with attention-deficit/hyperactivity disorder (ADHD). However, barriers such as job and transportation constraints hinder parents from attending face-to-face therapy appointments. The COVID-19 pandemic has further exacerbated these challenges. Objective: This study aimed to develop and test the feasibility of a social media-based parenting program for parents of children with ADHD, considering both the pre-existing challenges faced by parents and the additional barriers imposed by the COVID-19 pandemic. Methods: This study used a 5-stage design thinking process, encompassing empathizing with parents, defining their needs, ideating innovative solutions, prototyping the program, and testing the program with parents. Qualitative interviews were conducted with 18 parents of children with ADHD to understand their unique needs and values. Brainstorming techniques were used to generate creative ideas, leading to the creation of a prototype that was tested with 32 parents. Participants' engagement with the program was measured, and posttraining feedback was collected to assess the program's effectiveness. Results: Parents of children with ADHD encounter specific challenges, including managing impulsive behavior and difficulties in emotion regulation. The social media-based parenting program was delivered through the LINE app (Line Corporation) and consisted of 7 modules addressing topics related to ADHD management and effective parenting strategies. The program exhibited a high completion rate, with 84% (27/32) of participants successfully finishing it. Program provider-participant interaction peaked during the first week and gradually decreased over time. Qualitative feedback indicated that the program was feasible, accessible, and well received by participants. The LINE app was found to be convenient and helpful, and participants preferred content delivery once or twice per week, expressing acceptance for various content formats. Conclusions: This study emphasizes the significance of adopting a human-centered design thinking approach to develop parenting programs that cater to the unique needs and values of parents. By leveraging social media platforms, such as LINE, a parenting program can overcome the challenges posed by the COVID-19 pandemic and other constraints faced by parents. LINE offers a viable and feasible option for supporting parents of children with ADHD, with the potential for customization and widespread dissemination beyond the pandemic context.

Microfluidic devices have found extensive applications in mechanical, biomedical, chemical, and materials research. However, the high initial cost, low resolution, inferior feature fidelity, poor repeatability, rough surface finish, and long turn-around time of traditional prototyping methods limit their wider adoption. In this study, a strategic approach to a deterministic fabrication process based on in-situ image analysis and intermittent flow control called image-guided in-situ maskless lithography (IGIs-ML), has been proposed to overcome these challenges. By using dynamic image analysis and integrated flow control, IGIs-ML provides superior repeatability and fidelity of densely packed features across a large area and multiple devices. This general and robust approach enables the fabrication of a wide variety of microfluidic devices and resolves critical proximity effect and size limitations in rapid prototyping. The affordability and reliability of IGIs-ML make it a powerful tool for exploring the design space beyond the capabilities of traditional rapid prototyping.
(© 2023. The Author(s).)

Additive manufacturing is fast becoming a key process to manufacture a customized design with complex geometry and one process usually employed is based on the fused filament fabrication. Up to now this method is typically employed for rapid prototyping, it is therefore their mechanical strength is lower than the components manufactured using conventional casting process. It is well known that most failures are happened under repeated loads; therefore, a functional component mandatory needs to reach endurance strength under cyclic loads. Hence, this study set out to clarify several aspects of filament fused test specimens to determine their effect on accumulated damage to then predict component life under repeated loads. In this study is considered three waveforms such as sinusoidal, triangular and square, where it is observed that the square waveform provides the most severe loads. This study therefore makes a major contribution to research on the fatigue properties of parts manufactured using fused filament by reporting their fatigue behaviour under different fatigue load conditions. It would give a better understanding to improve the mechanical prediction of PLA, thereby it might be used to manufacture a functional component instead of only a prototype or spare part.
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).)

As biological imaging continues to rapidly advance, it results in increasingly complex image data, necessitating a reevaluation of conventional bioimage analysis methods and their accessibility. This perspective underscores our belief that a transition from desktop-based tools to web-based bioimage analysis could unlock immense opportunities for improved accessibility, enhanced collaboration, and streamlined workflows. We outline the potential benefits, such as reduced local computational demands and solutions to common challenges, including software installation issues and limited reproducibility. Furthermore, we explore the present state of web-based tools, hurdles in implementation, and the significance of collective involvement from the scientific community in driving this transition. In acknowledging the potential roadblocks and complexity of data management, we suggest a combined approach of selective prototyping and large-scale workflow application for optimal usage. Embracing web-based bioimage analysis could pave the way for the life sciences community to accelerate biological research, offering a robust platform for a more collaborative, efficient, and democratized science.
Competing Interests: WO is a co-founder of Amun AI AB, a commercial company that builds, delivers, supports and integrates AI-powered data management systems for academic, biotech and pharmaceutical industries. The remaining 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 Ouyang, Eliceiri and Cimini.)

Humans, Ki-67 Antigen, Positron Emission Tomography Computed Tomography, and Triple Negative Breast Neoplasms

Mathematical models based on partial differential equations (PDEs) can be exploited to handle clinical data with space/time dimensions, e.g. tumor growth challenged by neoadjuvant therapy. A model based on simplified assessment of tumor malignancy and pharmacodynamics efficiency was exercised to discover new metrics of patient prognosis in the OLTRE trial. We tested in a 17-patients cohort affected by early-stage triple negative breast cancer (TNBC) treated with 3 weeks of olaparib, the capability of a PDEs-based reactive-diffusive model of tumor growth to efficiently predict the response to olaparib in terms of SUV max detected at 18 FDG-PET/CT scan, by using specific terms to characterize tumor diffusion and proliferation. Computations were performed with COMSOL Multiphysics. Driving parameters governing the mathematical model were selected with Pearson's correlations. Discrepancies between actual and computed SUV max values were assessed with Student's t test and Wilcoxon rank sum test. The correlation between post-olaparib true and computed SUV max was assessed with Pearson's r and Spearman's rho. After defining the proper mathematical assumptions, the nominal drug efficiency (ε PD ) and tumor malignancy (r c ) were computationally evaluated. The former parameter reflected the activity of olaparib on the tumor, while the latter represented the growth rate of metabolic activity as detected by SUV max . ε PD was found to be directly dependent on basal tumor-infiltrating lymphocytes (TILs) and Ki67% and was detectable through proper linear regression functions according to TILs values, while r c was represented by the baseline Ki67-to-TILs ratio. Predicted post-olaparib SUV* max did not significantly differ from original post-olaparib SUV max in the overall, gBRCA-mutant and gBRCA-wild-type subpopulations (p > 0.05 in all cases), showing strong positive correlation (r = 0.9 and rho = 0.9, p < 0.0001 both). A model of simplified tumor dynamics was exercised to effectively produce an upfront prediction of efficacy of 3-week neoadjuvant olaparib in terms of SUV max . Prospective evaluation in independent cohorts and correlation of these outcomes with more recognized efficacy endpoints is now warranted for model confirmation and tailoring of escalated/de-escalated therapeutic strategies for early-TNBC patients.
(© 2023. The Author(s).)

Hot-stamped ultrahigh strength steel components are pivotal to automotive light-weighting. Steel blanks, often coated with an aluminum-silicon (Al-Si) layer to protect them from oxidation and decarburization, are austenitized within a furnace and then simultaneously quenched and formed into shape. The Al-Si coating melts within the furnace and reacts with iron from the steel to yield an intermetallic phase that provides some long-term corrosion protection. During the intermediate liquid phase, some of the coating may transfer to the furnace components, leading to maintenance costs and operational downtime. A detailed understanding of the coating transformation mechanism is needed to avoid such production issues while ensuring that final intermetallic coatings conform to specifications. We introduce cross-sectional Raman microscopic mapping as a method to rapidly elucidate the coating transformation mechanism. Raman spectroscopic fingerprints for relevant intermetallic compounds were determined using synthesized Al-Fe-Si ternary and Al-Fe binary compounds. These fingerprints were used to map the spatial distribution of intermetallic compounds through cross sections of Al-Si-coated 22MnB5 specimens that were heated at temperatures between 570 and 900 °C. These chemical maps show that the intermetallic fraction of the coating does not grow significantly until formation of η (Al 5 Fe 2 ) at the steel interface, suggesting that η facilitates extraction of iron from the steel and subsequent diffusion through the coating. Under the heating conditions used here, a series of reactions ultimately lead to a silicon-rich τ 2 (Al 3 FeSi) phase on top of the binary η phase. The technique presented here simplifies structural analysis of intermetallic compounds, which will facilitate prototyping of strategies to optimize hot stamping.
Competing Interests: The authors declare no competing financial interest.
(© 2023 The Authors. Published by American Chemical Society.)

Introduction: Investigation of molecular mechanisms of human disorders, especially rare diseases, require exploration of various knowledge repositories for building precise hypotheses and complex data interpretation. Recently, increasingly more resources offer diagrammatic representation of such mechanisms, including disease-dedicated schematics in pathway databases and disease maps. However, collection of knowledge across them is challenging, especially for research projects with limited manpower. Methods: In this article we present an automated workflow for construction of maps of molecular mechanisms for rare diseases. The workflow requires a standardized definition of a disease using Orphanet or HPO identifiers to collect relevant genes and variants, and to assemble a functional, visual repository of related mechanisms, including data overlays. The diagrams composing the final map are unified to a common systems biology format from CellDesigner SBML, GPML and SBML+layout+render. The constructed resource contains disease-relevant genes and variants as data overlays for immediate visual exploration, including embedded genetic variant browser and protein structure viewer. Results: We demonstrate the functionality of our workflow on two examples of rare diseases: Kawasaki disease and retinitis pigmentosa. Two maps are constructed based on their corresponding identifiers. Moreover, for the retinitis pigmentosa use-case, we include a list of differentially expressed genes to demonstrate how to tailor the workflow using omics datasets. Discussion: In summary, our work allows for an ad-hoc construction of molecular diagrams combined from different sources, preserving their layout and graphical style, but integrating them into a single resource. This allows to reduce time consuming tasks of prototyping of a molecular disease map, enabling visual exploration, hypothesis building, data visualization and further refinement. The code of the workflow is open and accessible at https://gitlab.lcsb.uni.lu/minerva/automap/.
Competing Interests: JP and LF are employed by MedBioinformatics Solutions SL. The remaining 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 Gawron, Hoksza, Piñero, Peña-Chilet, Esteban-Medina, Fernandez-Rueda, Colonna, Smula, Heirendt, Ancien, Groues, Satagopam, Schneider, Dopazo, Furlong and Ostaszewski.)

For the past years, fused deposition modeling (FDM) technology has received increased attention in the applications of industrial manufacturing fields, particularly for rapid prototyping, small batch production and highly customized products, owing to the merits of low-cost, user-friendliness and high design freedom. To further expand the application potential and promote the performance of the as-manufactured products, many efforts have been spent on the development of suitable materials for FDM applications. In recent years, the involvement of nanomaterials in the FDM-based polymer matrix, which has been demonstrated with great opportunities to enhance the performance and versatility of FDM printed objects, has attracted more and more research interest and the trend is expected to be more pronounced in the next few years. This paper attempts to provide a timely review regarding the current research advances in the use of nanomaterials to reinforce polymer filaments for the FDM technique. Polymer composite filaments based on nanomaterials such as carbon nanotubes, nanoclay, carbon fibers, graphene, metal nanoparticles and oxides are discussed in detail regarding their properties and applications. We also summarized the current research challenges and outlooked the future research trends in this field. This paper aims at providing a useful reference and guidance for skilled researchers and also beginners in related fields. Hopefully, more research advances can be stimulated in the coming years.

In this work, we introduce a polymer version of a previously developed silicon MEMS drop deposition tool for surface functionalization that consists of a microcantilever integrating an open fluidic channel and a reservoir. The device is fabricated by laser stereolithography, which offers the advantages of low-cost and fast prototyping. Additionally, thanks to the ability to process multiple materials, a magnetic base is incorporated into the cantilever for convenient handling and attachment to the holder of a robotized stage used for spotting. Droplets with diameters ranging from ∼50 µm to ∼300 µm are printed upon direct contact of the cantilever tip with the surface to pattern. Liquid loading is achieved by fully immersing the cantilever into a reservoir drop, where a single load results in the deposition of more than 200 droplets. The influences of the size and shape of the cantilever tip and the reservoir on the printing outcome are studied. As a proof-of-concept of the biofunctionalization capability of this 3D printed droplet dispenser, microarrays of oligonucleotides and antibodies displaying high specificity and no cross-contamination are fabricated, and droplets are deposited at the tip of an optical fiber bundle.
Competing Interests: Conflict of interestThe authors declare no competing interests.
(© The Author(s) 2023.)

Neural Networks, Computer, Algorithms, and Image Processing, Computer-Assisted methods

In this work, two methods are proposed for solving the problem of one-dimensional barcode segmentation in images, with an emphasis on augmented reality (AR) applications. These methods take the partial discrete Radon transform as a building block. The first proposed method uses overlapping tiles for obtaining good angle precision while maintaining good spatial precision. The second one uses an encoder-decoder structure inspired by state-of-the-art convolutional neural networks for segmentation while maintaining a classical processing framework, thus not requiring training. It is shown that the second method's processing time is lower than the video acquisition time with a 1024 × 1024 input on a CPU, which had not been previously achieved. The accuracy it obtained on datasets widely used by the scientific community was almost on par with that obtained using the most-recent state-of-the-art methods using deep learning. Beyond the challenges of those datasets, the method proposed is particularly well suited to image sequences taken with short exposure and exhibiting motion blur and lens blur, which are expected in a real-world AR scenario. Two implementations of the proposed methods are made available to the scientific community: one for easy prototyping and one optimised for parallel implementation, which can be run on desktop and mobile phone CPUs.

Introduction: Despite abundant evidence showing immunization as a lifesaving public health measure, a large proportion of Nigerian children are still not or fully vaccinated. Lack of awareness and distrust of the immunization process by caregivers are some of the reasons for poor immunization coverage which need to be addressed. This study aimed at improving vaccination demand, acceptance and uptake in Bayelsa and Rivers State, both in the Niger Delta Region (NDR) of Nigeria through a human-centered process of trust building, education and social support.
Methods: A quasi-experimental intervention christened Community Theater for Immunization (CT4I) was deployed in 18 selected communities between November 2019 and May 2021 in the two states. In the intervention localities, relevant stakeholders including the leadership of the health system, community leaders, health workers and community members were engaged and actively involved in the design and performance of the theaters. The content for the theater showcased real stories, using a human-centered design (HCD) of ideation, co-creation, rapid prototyping, feedback collection and iteration. Pre- and post-intervention data on the demand and utilization of vaccination services were collected using a mixed method.
Results: In the two states, 56 immunization managers and 59 traditional and religious leaders were engaged. Four broad themes implicating user and provider factors emerged from the 18 focus group discussions as responsible for low immunization uptake in the communities. Of the 217 caregivers trained on routine immunization and theater performances, 72% demonstrated a knowledge increase at the post-test. A total of 29 performances attended by 2,258 women were staged with 84.2% of the attendees feeling satisfied. At the performances, 270 children received vaccine shots (23% were zero-dose). There was a 38% increase in the proportion of fully immunized children in the communities and 9% decline in the proportion of zero-dose children from baseline.
Conclusion: Both demand- and supply-side factors were identified as responsible for poor vaccination in the intervention communities. Our intervention demonstrates that caregivers will demand immunization services if they are engaged through community theater using a human-centered design (HCD). We recommend a scaling up of HCD to address the challenge of vaccine hesitancy.
(© 2023. The Author(s).)

The field of additive manufacturing is quickly evolving from prototyping to manufacturing. Researchers are looking for the best parameters to boost mechanical strength as the demand for three-dimensional (3D) printers grows. The goal of this research is to find the best infill pattern settings for a polylactic acid (PLA)-based ceramic material with a universal testing machine; the impact of significant printing considerations was investigated. An X-ray diffractometer and energy-dispersive X-ray spectroscopy with an attachment of scanning electron microscopy were used to investigate the crystalline structure and microstructure of PLA-based ceramic materials. Tensile testing of PLA-based ceramics using a dog bone specimen was printed with various patterns, as per ASTM D638-10. The cross pattern had a high strength of 16.944 MPa, while the tri-hexagon had a peak intensity of 16.108 MPa. Cross3D and cubic subdivisions have values of 4.802 and 4.803 MPa, respectively. Incorporating the machine learning concepts in this context is to predict the optimal infill pattern for robust strength and other mechanical properties of the PLA-based ceramic model. It helps to rally the precision and efficacy of the procedure by automating the job that would entail substantial physical effort. Implementing the machine learning technique to this work produced the output as cross and tri-hexagon are the efficient ones out of the 13 patterns compared.
Competing Interests: The authors declare no competing financial interest.
(© 2023 The Authors. Published by American Chemical Society.)

Drug Delivery Systems, Gene Transfer Techniques, Osteogenesis, Tissue Engineering methods, and Tissue Scaffolds chemistry

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.)

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.)

Network Meta-Analysis, Printing, Three-Dimensional, Stereolithography, Models, Dental, and Computer-Aided Design

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.)

Humans, Models, Anatomic, Computer Simulation, Hand, Anastomosis, Surgical education, Clinical Competence, Thoracic Surgical Procedures, and Simulation Training

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.)

Ultrasonography methods, Image Processing, Computer-Assisted, Phantoms, Imaging, Transducers, Tomography, and Tomography, X-Ray Computed

Fast imaging methods are needed to promote 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 [Formula: see text] mean element position error, and a [Formula: see text] deviation in matching layer thickness. The nominal acoustic performance was measured using hydrophone scans and watershot data, and the 61.2 dB signal-to-noise ratio (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 interelement variation in acoustic performance was typically < 10% without using normalization, meaning that the elements can be modeled identically during image reconstruction, removing the need for individual source definitions based on hydrophone measurements. Finally, data from a phantom experiment were successfully reconstructed. These results demonstrate that the open-UST system is accessible for users and is suitable for UST imaging research.

This paper presents the design, manufacturing, and characterization of a three-dimensional (3D)-printed and electromagnetically actuated adjustable optical slit structure. The device comprises magnet-attached slits connected to the main frame via two springs controlled by external coils. To analyze the forces acting on the springs and simulate the mechanical behavior of the device, we developed both analytical and finite-element models. After fabricating the device using fused deposition, we conducted a series of tests to evaluate its performance. These tests included (1) analyzing the opacity of the slit blade as a function of its thickness, (2) measuring the temperature increase resulting from the power applied to the coils to determine the operable range of the structure, and (3) evaluating the hysteresis, repeatability, and resolution (minimum step) of the device. The experimental works were crucial to assessing the device's practicality and optimizing its performance for specific applications, which reveals a maximum slit width of ∼450µ m , with ∼6.4µ m step size within this study. Overall, our developed slit device has the potential to be useful in various optics-related laboratories due to its compatibility with conventional 1-inch (25.4 mm) diameter optomechanical mounts, compact form, low power consumption, and rapid prototyping capability with hybrid materials in a cost-friendly fashion, owing to the 3D-printing technology. We discuss an application where the adjustable slit is employed in a combined laser-scanning microscope and a spectrometer, highlighting its versatility and potential for the future.

Computer Simulation, Monte Carlo Method, Radiotherapy Dosage, Radiotherapy Planning, Computer-Assisted, Radiometry methods, Electrons, and Photons

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.)

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.)

The three-dimensional (3D) printing itself is not a novel technology, it is more than 30 years old. Stereolithographic (SLA) technology has been used as the first and popular technology for medical application of 3D printing. Since 1991 Radiology and Plastic Surgery have published articles about SLA for rapid prototyping anatomical 3D models. Medical applications of 3D printing have been popularizing and stabilizing so far. Implantable medical devices such as metal or absorbable implants, surgical guide systems, prosthesis and orthosis, and 3D anatomical models for normal or diseased anatomy have been developing and expanding its markets so far. There are many obstacles, such as insurance, authorization as a medical device, and lack of standards technology for further expansion of medical applications. Many technical specifications and guidelines for authorization as medical device have been published by regulatory bodies from many countries. Even though international standards for 3D printing have been developing more and more, there have been few standards for medical application of 3D printing. In this harsh environment academia, company, research institute, regulatory bodies, and government have been doing good job for the development of 3D printing industry.
Competing Interests: The author has no potential conflicts of interest to disclose.
(Copyright © 2023 The Korean Brain Tumor Society, The Korean Society for Neuro-Oncology, and The Korean Society for Pediatric Neuro-Oncology.)