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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.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing for financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Reactive Oxygen Species, Printing, Three-Dimensional, Polyesters, Acrylates, Methacrylates, and Chlorella vulgaris

3D printing represents a key enabling technology in designing photobioreactors. It allows rapid prototyping of complex geometries at an affordable price. Yet, no study dealt with the biocompatibility of 3D printing material with microalgae. Thus microalga Chlorella vulgaris was cultivated in contact with different 3D printing materials (Acrylonitrile Butadiene Styren - ABS, PolyCarbonate Blend - PC-Blend, PolyLactic acid - PLA, and acrylate methacrylate resin). Cell status was analyzed using flow cytometry, fluorometry, and pigment profiling. Results revealed that acrylate methacrylate resin material inhibits growth, a constant rise in intracellular reactive oxygen species, and a decrease in photosynthetic apparatus functioning. On the contrary, ABS, PC-Blend, and PLA led to nominal perfromances. Nevertheless, PLA was the only material that did not induce an early onset of intracellular reactive oxygen species. Therefore, resin can be ruled out as photobioreactor material, ABS and PC-Blend could be used after a curation period, and PLA induces no detectable perturbations by the means used in this study.
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, Cemeteries, and Cremation history

The cremation has been documented since prehistoric times and it was a common funerary custom until the advent of Catholicism. Falling into disuse, during XVII-XVIII centuries there were new movements to bring it back according to modern criteria, mainly due to hygienic reasons and cemeteries overcrowding. This also led to the prototyping of new crematory ovens to improve the ancient open-air pyre. Lodovico Brunetti was the first to carry out a crematory experimental research in the modern countries. Since Brunetti's studies were based on the study of ancient cremations, a comparison with a modern experience of reconstruction of archaeological cremation is presented to evaluate the validity of his crematorium oven. Furthermore, the social and religious aspects related to Brunetti's inventions and the revitalization of cremation shows how tools and technologies and also the cultural environment have evolved over the years, effectively accepting the cremation practice as an alternative to inhumation.
Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Humans, Child, Child, Preschool, Carbon Dioxide, Ventilators, Mechanical, Monitoring, Physiologic methods, Respiration, Artificial methods, and Home Care Services

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, Feasibility Studies, Sports, Exercise, Sedentary Behavior, and Health Promotion

Aim: This paper describes the design of the 'Move More' study, which aims to develop and assess the feasibility of a social-prescribing intervention to increase physical activity among physically inactive Danes.
Background: Physical inactivity constitutes a public-health challenge in Denmark. Social prescribing may be a promising tool to tackle physical inactivity by linking physical activity support from general practitioners with community-based activities in sports clubs, as this may help physically inactive citizens become more physically active. Given the range of stakeholders and behaviours required for social prescribing of physical activity, an intervention that harnesses this approach may constitute a complex intervention. The methods and decisions made in the stages of developing complex interventions are seldom reported. The present study enabled us to describe how co-creation can be used in a pragmatic development process for a complex intervention that considers the needs of stakeholders and the conditions of the delivery context.
Methods: The study is based on the core elements of the development and feasibility phases of the Medical Research Council Framework for Developing and Evaluating Complex Interventions. Additionally, it is informed by a framework for the co-creation and prototyping of public-health interventions, drawing from a scoping review, stakeholder consultations and co-creation workshops. Ultimately, a feasibility study will be conducted to refine the programme theory by introducing the proposed intervention in case studies.
Perspectives: The study will result in a prototype intervention manual and recommendations for implementation of an adapted social-prescribing intervention targeting physical inactivity in Denmark.
Competing Interests: Declaration of conflicting interestsThe authors declared no potential conflicts of interest with respect to the research, authorship and/or publication of this article.

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.)

Humans, Computer Simulation, User-Computer Interface, Clinical Competence, Spinal Puncture, and Students, Medical

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.)

Ti 6Al–4V alloy, Zirconia, Co–Cr–Mo alloy additive manufacturing, Osteoarthritis, Knee joint, FDM, Internal medicine, RC31-1245, Surgery, and RD1-811

Additive manufacturing (Rapid Prototyping) is a significant innovation in medical field. It allows scientists to create custom-made parts that are often more precise and robust than their standard counterparts. Osteoarthritis (OA) is very common and serious problems in aging people. It is a progressive disease that affects the cartilage, the substance that cushions the bones and joints. Artificial knee joints are being developed as a sort of replacement for the human knee joint. One of the most intricate parts of the human body is the knee joint. This complex joint comprises of a ball-and-socket relationship, which is a very difficult part of the anatomy to design. The joint consists of both the kneecap and the Cartilage, and it has been designed with the intention of having the joint supported by a bone, rather than a cartilage. In this review article the results of a recent study, which was performed by researchers from the various renowned universities of Europe & United States of America over Artificial Knee Joint by Additive Manufacturing Technology.

Post-consumer recycling, Circular economy, Metalized film, Thermal properties, Mechanical properties, Renewable energy sources, TJ807-830, Environmental engineering, and TA170-171

In the recycling point of view, the metalized plastic film is widely known to be one of the most difficult materials to be recycled due to its structural complexity. This paper investigates the effects of the ground metalized-plastic film (MF) as a filler and reinforcement in recycled polypropylene (rPP) packaging to produce a new material through circular economy. MF was incorporated to rPP from 2 to 10 wt% and it was processed by using a twin-screw extruder and an injection molding machine. For MF, elemental analysis, and x-ray diffractometer (XRD) confirmed the existence of C, O, and Al, while the differential scanning calorimetry (DSC) result evidenced the melting position of linear-low density polyethylene (LLDPE). For, rPP/MF composites, MF was found to significantly reinforce rPP with the increased tensile strength. A maximum increase of the tensile strength by around 33% was observed when MF was added at 8 wt%. Elongation at break was found to reduce with MF loading. However, there was no significant difference among rPP with 6–10 wt% MF. DSC results indicated the shifts of both crystallization and melting peaks together with the reduction of the degree of crystallinity (Xc). Based on the tensile strength, tensile elongation at break results together with the statistical analysis and waste utilization issues, the rPP with 10 wt% MF formulation was selected as a final product prototyping.

Digital mental health, Human-centered design, Methodology, Information technology, T58.5-58.64, Psychology, and BF1-990

As digital mental health interventions (DMHIs) proliferate, there is a growing need to understand the complexities of moving these tools from concept and design to service-ready products. We highlight five case studies from a center that specializes in the design and evaluation of digital mental health interventions to illustrate pragmatic approaches to the development of digital mental health interventions, and to make transparent some of the key decision points researchers encounter along the design-to-product pipeline. Case studies cover different key points in the design process and focus on partnership building, understanding the problem or opportunity, prototyping the product or service, and testing the product or service. We illustrate lessons learned and offer a series of questions researchers can use to navigate key decision points in the digital mental health intervention (DMHI) development process.

Nanocellulose, Alginate, Hydrogel, Films, 3D printing, Architectural design, Materials of engineering and construction. Mechanics of materials, and TA401-492

Cellulose nanofibril hydrogel mixed with an aqueous solution of sodium alginate is a novel bio-based material suitable for 3D printing of lightweight membranes with exquisite properties and sustainable traits. However, fundamental knowledge enabling its applications in architectural design is still missing. Hence, this study examines the macro-scale features of lightweight membranes from cellulose nanofibril-alginate hydrogel, relevant for the design of various interior architectural products, such as wall claddings, ceiling tiles, room partitions, tapestries, and window screens. Through iterative prototyping experiments involving robotic 3D printing of lightweight membranes, their upscaling potential is demonstrated. Correlations between toolpath designs and shrinkages are also characterized, alongside an in-depth analysis of coloration changes upon ambient drying. Further, the tunability potential of various architectural features, enabled by bespoke 3D printing toolpath design, is discussed and exemplified. The aim is to expose the wide palette of design possibilities for cellulose nanofibril-alginate membranes, encompassing variations in curvature, porosity, translucency, texture, patterning, pliability, and feature sizes. The results comprise an important knowledge foundation for the design and manufacturing of custom lightweight architectural products from cellulose nanofibril-alginate hydrogel. These products could be applied in a variety of new bio-based, sustainable interior building systems, replacing environmentally harmful, fossil-based solutions.

Hole flanging, Incremental sheet forming, Hardness, Artifiical neural network (ANN), Forming limit diagram (FLD), Numerical simulation, and Technology

In the single point incremental hole flanging (SPIHF) process, a sheet material with pre-cut holes is deformed using the SPIF technique to generate a flange, making it an effective approach for low volume manufacturing and quick prototyping. In the case of the SPIHF technique, the post-forming hardness property, the forming limit diagram (FLD), and spring-back phenomena are not completely evaluated. To this end, this paper employs experimental investigation and numerical validation to analyse the impact of SPIHF process parameters like tool diameter, feed rate, spindle speed, and initial hole diameter on these aspects for the truncated incrementally formed components made from AA1060 aluminium alloy and DC01 carbon steel. The plasticity behaviour of both sheet metals was simulated using the Workbench LS-DYNA model and ANSYS software version 18. Additionally, Cowper Symonds power-law hardening was added to the model to account for material properties. The average post-hardness of AA1060 and DC01 was evaluated using an SPIHF prediction model based on the performance of an artificial neural network (ANN). This ANN model was developed using a feed-forward back-propagation network trained using the Levenberg-Marquardt approach. The ANNs 4-n-1 were created by varying the transfer functions and the number of hidden neurons. Greater spindle speed and bigger pre-cut holes were shown to significantly increase the post-formed hardness of the truncated components, whereas the converse was seen when using a higher feed rate and a larger tool diameter. In addition, the FLD and spring-back improved dramatically with larger hole diameters. Employing correlation coefficient (R) and mean square error (MSE) as validation measures, it was shown that the established ANN models accurately predicted the SPIHF process response. Both the DC01 and AA1060 neural network models with a 4-8-1 network architecture performed very well, with MSE and R values of 0.0000105 and 1 for DC01 and 0.02613 and 0.99982 for AA1061.

Biomedical imaging, 3D printing, prototyping, material science, polymer characterization, Materials of engineering and construction. Mechanics of materials, TA401-492, Biotechnology, and TP248.13-248.65

ABSTRACTIn biomedical imaging, it is desirable that custom-made accessories for restraint, anesthesia, and monitoring can be easily cleaned and not interfere with the imaging quality or analyses. With the rise of 3D printing as a form of rapid prototyping or manufacturing for imaging tools and accessories, it is important to understand which printable materials are durable and not likely to interfere with imaging applications. Here, 15 3D printable materials were evaluated for radiodensity, optical properties, simulated wear, and capacity for repeated cleaning and disinfection. Materials that were durable, easily cleaned, and not expected to interfere with CT, PET, or optical imaging applications were identified.

3d food printing, extrusion, food waste, sustainability, dysphagia, hydrocolloids, Science, Manufactures, and TS1-2301

Food waste utilisation and zero waste approach are among the many ways of building a sustainable economy. Food waste as authentic edible food being accepted by the consumers still has many barriers to overcome. One tool to help in the valorisation of food waste to value-added products is three-dimensional food printing (3DFP). These products can lead to easier and greater acceptance of food waste by consumers, having familiar nature with respect to taste, texture and appearance as other consumables. In the present study, food ink recipes were formulated from spinach stems and kale stalks, the common green leafy vegetable wastes. These spinach and kale inks were then characterised on their rheological properties of shear thinning and yield stress. The inks were subjected to IDDSI tests meant for standardisation of soft foods for dysphagia patients. This paper demonstrates ways of converting vegetable wastes into edible diets that are aesthetically pleasing through 3DFP.

Multiple materials, additive manufacturing, wire arc additive manufacturing, Science, Manufactures, and TS1-2301

ABSTRACTThe dynamic landscape of additive manufacturing (AM) is undergoing a transformative phase with the advent of multiple wire arc AM (MWAAM) processes. This systematic review offers an exhaustive exploration of the latest advancements and multifaceted applications of these innovative techniques within the realms of AM and welding. Prominently discussed processes encompass Bi-Metallic Wire Arc Additive Manufacturing, Twin Wire Arc Additive Manufacturing, Tandem Gas Metal Arc Welding, Twin-Wire Plasma Arc Additive, and Hybrid Wire Arc Additive Manufacturing. These techniques, instrumental in fabricating an array of materials from titanium aluminides to low-carbon steel, underscore the versatility and potential of modern AM. The application breadth spans key industries such as aerospace, naval, automotive, and energy, highlighting the ubiquity and relevance of these processes. While they promise enhanced productivity, improved material attributes, and economic efficiencies, challenges persist, including the need for meticulous parameter control, an in-depth grasp of foundational physics, and the development of sophisticated predictive models. Projecting into the future of AM, this review anticipates a harmonised integration of computational advancements with automation, positioning these MWAAM processes as pivotal in the next wave of manufacturing innovations.

additive manufacturing, 3d printing, field assistance, magnetic field assistance, electric field assistance, acoustic field assistance, additive manufacturing of polymers, additive manufacturing of metals, Science, Manufactures, and TS1-2301

Additive manufacturing (AM) has emerged as a transformative technology capable of fabricating complex geometries and multi-material structures across various industries. Despite its potential, challenges persist in terms of limited material selection, anisotropic properties, and achieving functional microstructures in polymer and metal composites. Field-assisted additive manufacturing (FAAM) employs external fields like acoustic, magnetic, and electric fields. It has shown promise in addressing these limitations by controlling filler orientation and concentration in polymeric composites and improving surface finish and microstructure in metals. This review paper provides a comprehensive analysis of the state-of-the-art FAAM processes for polymer and metal composites, focusing on material compatibility, the mechanics of each field, and their integration with AM technologies as well as current applications, limitations, and potential future directions in the development of FAAM processes. Enhancing FAAM process understanding can create tailored anisotropic composites, enabling innovative applications in aerospace, automotive, biomedical fields, and beyond.

3d printing, additive manufacturing, cooperative robots, mobile robots, teams of robots, cooperative printing, Science, Manufactures, and TS1-2301

Additive manufacturing (AM) is a key enabler and technological pillar of the fourth industrial revolution (Industry 4.0) as it increases productivity and improves resource efficiency. However, current AM systems present some limitations in terms of fabrication time, versatility, and efficiency. The concept of teams of robots represents a novel approach for AM aiming to address these limitations. This review paper discusses the current state-of-the-art of the use of cooperative AM systems based on gantry systems, robotic arms, and mobile robots. The information flow, path planning and slicing strategies are discussed in detail, and several examples of the use of cooperative AM systems are provided. Finally, major research challenges and future perspectives are discussed.

3D printing, online path planning, mobile 3D printer, real-time path planning, cooperative printing, Science, Manufactures, and TS1-2301

ABSTRACTCooperative printing, where multiple printheads concurrently print a part, significantly improves printing speed. However, current literature only discussed offline path planning, in which the toolpaths are generated before the printing process starts. Offline path planning is unreliable and leads to collisions for systems with uncertainties such as mobile robots. In this paper, we developed several online path planning algorithms for cooperative printing by mobile robots that allow toolpath allocation in real time. Unlike offline path planning, it is not possible to replan the layer in case of collision in online systems. Thus, we developed a novel algorithm that guarantees collision avoidance in real time. The system was evaluated through both simulations and experiments. The mobile robots cooperatively printed several layers which showed that the system can significantly increase the speed of 3D printing. This work stands as the first in the literature that allows online path planning for cooperative printing.

material jetting, 3d inkjet printing, print parameters, printed layer height, statistical analysis, interaction effect, Science, Manufactures, and TS1-2301

3D inkjet (3D-IJ) printing is recognised for its potential in high-value applications, including printed electronics, tissue engineering and bio-inspired structures, given its precision and ability to deposit multiple materials. The quality of 3D-IJ printed parts is contingent upon meticulous control of the process governing parameters. This study experimentally investigates the influence of various parameters within the 3D-IJ process, i.e., printing resolution, coverage percentage, droplet volume, printing speed and UV-Power and their interaction effects on the printed layer height. The results were analysed statistically using ANOVA and a quadratic regression model was developed to quantitatively identify the relationship between the process response and parameters. Except UV-Power, all parameters, and their interactions with each other had noticeable effects on the printed layer height, with a distinct trend observed for each, affecting the height that ranged from 4.73 µm to 98.58 µm. Increasing printing resolution, coverage percentage and droplet volume resulted in an increase in layer height as all three parameters contribute to a larger volume of dispensed material per layer. Printing resolution was found to be the most influential parameter, evidenced by a significant p-value. Finally, the optimal printing parameters for two scenarios, highest printed layer and cost-effective printing were individually identified.

Additive manufacturing, direct ink writing, high solid loadings, rheology, characterisation, Science, Manufactures, and TS1-2301

ABSTRACTMaterial extrusion additive manufacturing is of increased interest in producing materials with very high loadings of particles, specifically through the use of the direct ink write (DIW), or robocasting, technique and the use of highly loaded particle suspensions (HLS). Applications from biomedical composites to solid rocket propellants to powder metallurgy green bodies would benefit from the complex parts enabled by additive manufacturing but require very high particle contents during processing. This leads to very high viscosity fluids and challenges in flowing and curing the inks. In this comprehensive review, we examine the main components of designing an ink formulation and a DIW process: the ink rheology, the print mechanics and the solidification/post-processing. Our expanded discussion of these elements includes an introduction to the basics as well as the latest research in the field, so serves to both introduce a new practitioner and generate new ideas for those already working in the area. We finish with a discussion of two important applications and a perspective on the future directions of DIW for highly loaded particle materials.