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Traveling wave structures for lossless ion manipulation (TW-SLIM) has proven a valuable tool for the separation and study of gas-phase ions. Unfortunately, many of the traditional components of TW-SLIM experiments manifest practical and financial barriers to the technique's broad implementation. To this end, a series of technological innovations and methodologies are presented which enable for simplified SLIM experimentation and more rapid TW-SLIM prototyping. In addition to the use of multiple independent board sets that comprise the present SLIM system, we introduce a low-cost, multifunctional traveling wave generator to produce TW within the TW-SLIM. This square-wave producing unit proved effective in realizing TW-SLIM separations compared to traditional approaches. Maintaining a focus on lowering barriers to implementation, the present set of experiments explores the use of on-board injection (OBI) methods, which offer potential alternatives to ion funnel traps. These OBI techniques proved feasible and the ability of this simplified TW-SLIM platform to enhance ion accumulation was established. Further experimentation regarding ion accumulation revealed a complexity to ion accumulation within TW-SLIM that has yet to be expounded upon. Lastly, the ability of the presented TW-SLIM platform to store ions for extended periods (1 s) without significant loss (<10%) was demonstrated. The aforementioned experiments clearly establish the efficacy of a simplified TW-SLIM platform which promises to expand adoption and experimentation of the technique.
(Copyright © 2022 Elsevier B.V. All rights reserved.)

Electromagnetic Phenomena, Phantoms, Imaging, Prostheses and Implants, and Wireless Technology

Objective: Computational modeling is increasingly used to design charging systems for implanted medical devices. The design of these systems must often satisfy conflicting requirements, such as charging speed, specific absorption rate (SAR) and coil size. Fast electromagnetic solvers are pivotal for enabling multi-criteria optimization. In this paper, we present an analytical model based on the quasi-static approximation as a fast, yet sufficiently accurate tool for optimizing inductive charging systems.
Methods: The approximate model was benchmarked against full-wave simulations to validate accuracy and improvement in computation time. The coupling factor of two test coils was measured for lateral and axial displacements and the SAR was measured experimentally in a PAA phantom.
Results: The approximate model takes only 11 seconds to compute a single iteration, while the full-wave model takes 5 hours to compute the same case. The maximum difference with full-wave simulations was less than 24% and the mean difference less than 2%. Adding a novel figure of merit into the multi-criterion optimization resulted in a 16% higher charging speed. The measured results of the SAR and coupling factor are within a 5 mm coil offset margin.
Conclusion: The proposed approximate model succeeds as a rapid prototyping tool, enabling fast and sufficiently accurate optimization for wireless charging systems.
Significance: The approximate model is the first of its kind to compute both the coupling factor and the SAR near conducting structures fast enough to enable optimization of charging speed.

The use of personal protective equipment (PPE) has become essential to reduce the transmission of coronavirus disease 2019 (COVID-19) as it prevents the direct contact of body fluid aerosols expelled from carriers. However, many countries have reported critical supply shortages due to the spike in demand during the outbreak in 2020. One potential solution to ease pressure on conventional supply chains is the local fabrication of PPE, particularly face shields, due to their simplistic design. The purpose of this paper is to provide a research protocol and cost implications for the rapid development and manufacturing of face shields by individuals or companies with minimal equipment and materials. This article describes a best practice case study in which the establishment of a local manufacturing hub resulted in the swift production of 12,000 face shields over a seven-week period to meet PPE shortages in the North-West region of Ireland. Protocols and processes for the design, materials sourcing, prototyping, manufacturing, and distribution of face shields are described. Three types of face shields were designed and manufactured, including Flat, Laser-cut, and 3D-printed models. Of the models tested, the Flat model proved the most cost-effective (€0.51/unit), while the Laser-cut model was the most productive (245 units/day). The insights obtained from this study demonstrate the capacity for local voluntary workforces to be quickly mobilised in response to a healthcare emergency, such as the COVID-19 pandemic.
(© 2022 The Authors.)

Electromagnetic fields, Antennas (Electronics), Wireless sensor networks, and Rapid prototyping

Keywords: metallization; radio frequency performance; SLA reflector; three-dimensional printed Abstract A novel high precision and lightweight reflector antenna is proposed. The fabrication process of the reflector adopted Stereo Lithography Apparatus (SLA) printed and metallization. The proposed SLA Reflector (SLAR) antenna structure adopts three-dimensional-printed, which can design complex geometric shapes flexibly and rapid prototyping. That is a good substitute for the traditional method of millimeter wave reflector processing. In order to realize radio frequency (RF) characteristics perfectly, the metallization process of photosensitive resin was elaborated, which realized by first electroless nickel plating, then copper electroplating, and finally chromium electroplating on the protective layer. For verification, the designed reflector antenna was manufactured and measured. The reflectivity of SLAR was measured well by the bow method, which validates excellent fabrication accuracy and reliability. The gain and pattern were measured in the anechoic chamber. The results show that the proposed reflector antenna achieves the gain of 25dBi and the 3dB gain bandwidth of 43% over the full Ka-band. A good agreement can be observed between measurement and simulation. Biographical information: Liwei Guo received the B.E. degree in from the Guilin University of Electronic Technology, Guilin, China in 2006. She is currently pursuing the PhD degree in Guilin University of Electronic Technology, Guilin, China. Her current research interests include metasurfaces, millimeter-wave reflector antenna. Simin Li received the B.S. degree in wireless communication engineering from Nanjing University of Posts and Telecommunications, Nanjing, China, in 1984, and the M.S. and PhD degrees in electronics engineering from the University of Electronic Science and Technology of China, Chengdu, China, in 1989 and 2007, respectively. Dr. Li is currently the President and a Professor with Guangxi University of Science and Technology, Liuzhou, China. His current research interests include the design of electrically small antennas, antenna arrays for high-frequency communication systems, and wireless sensor networks. Xing Jiang received the Master's degree in electromagnetic field and microwave technology from Beijing Institute of Technology, Beijing, China, in 1986. Since 2000, she has been a Professor with the Guilin University of Electronic Technology, Guilin, China. She was sponsored by the National Natural Science Foundation of China and the Natural Science Foundation of Guangxi. Her research interests include smart communication system design, conformal antenna array, and bioelectromagnetics. Xin Liao received the B.E. degree from Chongqing University of Posts and Telecommunications, Chongqing, China, in 1990. He is currently a Lecturer with the Guilin University of Electronic Technology, Guilin, China. His research interests include Electromagnetic Compatibility and antenna measurement. Ying Zhang received the B.E. degree in Harbin Institute of Technology of optical instrument. Now she is a researcher at Beijing Simulation Center. Her research interest is the simulation of visible light/infrared guidance and control systems. Bin Shi is an associate researcher- in Beijing Simulation Center. Her research interest is the simulation of radio frequency target accuracy. Article Note: Funding information Guangxi Innovation Driven Development Special Fund Project, Grant/Award Number: GUIKEAA19254012; Innovation Project of Guangxi Graduate Education, Grant/Award Number: YCBZ2019051; National Natural Science Foundation of China, Grant/Award Numbers: 61761012, 61661011 Byline: Liwei Guo, Simin Li, Xing Jiang, Xin Liao, Ying Zhang, Bin Shi

Background: Management of child healthcare can be negatively affected by incomplete recording, low data quality, and lack of data integration of health management information system (HMIS) to support decision making and public health program needs. Given the importance of identifying key determinants of child health via capturing and integrating accurate and high-quality information, we aim to address this gap through the development and testing requirements for an integrated child health information system.
Subjects and Method: A five-phase design thinking approach including empathizing, defining, ideation, prototyping, and testing was applied. We employed observation and interviews with the health workers at the primary health care network to identify end-users challenges and needs using tools in human-centered design and focus group discussion. Then, a potential solution to the identified problems was developed as an integrated maternal and child health information system (IMCHIS) prototype and tested using Software Quality Requirements and Evaluation Model (SQuaRE) ISO/IEC 25000.
Results: IMCHIS was developed as a web-based system with 74 data elements and seven maternal and child healthcare requirements. The requirements of "child disease" with weight (0.26), "child nutrition" with weight (0.20), and "prenatal care" with weight (0.16) acquired the maximum weight coefficient. In the testing phase, the highest score with the weight coefficient of 0.48 and 0.73 was attributed to efficiency and functionality characteristics, focusing on software capability to fulfill the tasks that meet users' needs.
Conclusion: Implementing a successful child healthcare system integrates both maternal and child healthcare information systems to track the effect of maternal conditions on child health and support managing performance and optimizing service delivery. The highest quality score of IMCHIS in efficiency and functionality characteristics confirms that it owns the capability to identify key determinants of child health.
(The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial-License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/).)

3D printing is known as a fast, inexpensive, reproducible method for producing prototypes but is also fast becoming recognised as a scalable, advanced manufacture process. Two types of lab-scale, 3D printed plastic, fixed-film, flow-through photocatalytic reactors are described, both of which are sinusoidal in shape, and only differ in that one has no baffles, reactor A, whereas the other has, reactor B. Both reactors are lined with a P25 TiO 2 /polylactic acid (PLA) coating, which, after UVA pre-conditioning, is used to photocatalyse the bleaching of circulating aqueous solutions of either methylene blue, MB, or phenol, PhOH, repeatably, without any obvious loss of activity. The rate of the photocatalysed bleaching of MB exhibited by reactor B shows a much lower dependence upon flow rate than reactor A, due to the greater lateral mixing of the laminar flow streams produced by the baffles. The photonic efficiencies of reactor A for the photocatalysed bleaching of MB and PhOH were determined to be 0.025% and 0.052%, respectively, and the photocatalytic space-time yields (PSTY) to be 0.98 × 10 -4 and 1.49 × 10 -4 m 3 of reaction solution.m -3 reactor volume.day -1 .kW -1 , respectively. This is the first example of an all plastic, 3D printed photocatalytic reactor and demonstrates the advantages of 3D printing for prototyping. Given the 3D printing is a scalable process, possible potential areas of application are discussed briefly.
(© 2022. The Author(s).)

Openly shared low-cost electronic hardware applications, known as open electronics, have sparked a new open-source movement, with much untapped potential to advance scientific research. Initially designed to appeal to electronic hobbyists, open electronics have formed a global "maker" community and are increasingly used in science and industry. In this perspective article we review the current costs and benefits of open electronics for use in scientific research ranging from the experimental to the theoretical sciences. We discuss how user-made electronic applications can help (I) individual researchers, by increasing the customization, efficiency, and scalability of experiments, while improving data quantity and quality; (II) scientific institutions, by improving access to customizable high-end technologies, sustainability, visibility, and interdisciplinary collaboration potential; and (III) the scientific community, by improving transparency and reproducibility, helping decouple research capacity from funding, increasing innovation, and improving collaboration potential among researchers and the public. We further discuss how current barriers like poor awareness, knowledge access and time investments can be resolved by increased documentation and collaboration and provide guidelines for academics to enter this emerging field. We highlight that open electronics are a promising and powerful tool to help scientific research to become more innovative and reproducible and offers a key practical solution to improve democratic access to science.
(© The Author(s) 2022. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology.)

Background: Following total sacrectomy, the continuity between the spine and pelvis is necessary for ambulation and to enable patients to resume daily living activities sooner during rehabilitation. Reconstructing spinopelvic stability after a total sacrectomy is a challenge that has not yet been overcome. Thus, the objectives of the present study are as follows:Establish a new system of reconstructing the spinopelvic region after a total sacrectomy using a rapid prototyping technique to design the sacral replacement pieces.Evaluate the biomechanical properties of this system.Study a new reconstruction system for the spinopelvic joint that reduces reconstruction failures after total sacrectomy, reducing postoperative complications and allowing early sitting and standing of these patients.
Methods: A sacral replacement implant was designed according to an authentic clinical case of a patient who had undergone a total sacrectomy. Using the finite element method, a biomechanical study was carried of 2 reconstructions that had been performed using the new prosthetic. The results of the study were compared with 4 other reconstruction models.
Results: A maximum von Mises stress of 112 MPa and a vertical displacement of -0.13 mm in L5 were observed in the models of the sacral implant that had been generated. A maximum rigidity of 861.5 Nm/mm was observed in the models when assuming a reduction in rigidity of more than 85% with respect to the other models assessed. In all models, maximum tension was concentrated in the rods joining L5 with the screws anchored to the pelvis.
Conclusions: The sacral prosthesis substitution after a total sacrectomy produced a profound reduction in stress in the instrumentation and the bone structure as well as smaller vertical displacement, the lowest values ever reported. These results indicated that the assembly was rigid and stable and would prevent the collapse of the spine in the pelvis. According to stress values, the replacement piece was not likely to rupture as a consequence of static load or implant fatigue.
(This manuscript is generously published free of charge by ISASS, the International Society for the Advancement of Spine Surgery. Copyright © 2022 ISASS. To see more or order reprints or permissions, see http://ijssurgery.com.)

We report automated fabrication of solid-contact sodium-selective (Na + -ISEs) and potassium-selective electrodes (K + -ISEs) using a 3D printed liquid handling robot controlled with Internet of Things (IoT) technology. The printing system is affordable and can be customized for the use with micropipettes for applications such as drop-casting, biological assays, sample preparation, rinsing, cell culture, and online analyte monitoring using multi-well plates. The robot is more compact (25 × 30 × 35 cm) and user-friendly than commercially available systems and does not require mechatronic experience. For fabrication of ion-selective electrodes, a carbon black intermediate layer and ion-selective membrane were successively drop-cast on the surface of stencil-printed carbon electrode using the dispensing robot. The 3D-printed robot increased ISE robustness while decreasing the modification time by eliminating manual steps. The Na + -ISEs and K + -ISEs were characterized for their potentiometric responses using a custom-made, low-cost (<$25) multi-channel smartphone-based potentiometer capable of signal processing and wireless data transmission. The electrodes showed Nernstian responses of 58.2 ± 2.6 mV decade -1 and 56.1 ± 0.7 mV decade -1 for Na + and K + , respectively with an LOD of 1.0 × 10 -5  M. We successfully applied the ISEs for multiplexed detection of Na + and K + in urine and artificial sweat samples at clinically relevant concentration ranges. The 3D-printed pipetting robot cost $100 and will pave the way for more accessible mass production of ISEs for those who cannot afford the expensive commercial robots.
(Copyright © 2022 Elsevier B.V. All rights reserved.)