Device Technology Research Articles

Heartwheels! STEM Mobile Outreach Program.

Heartwheels! STEM Mobile Outreach is a scientist-led collaborative, innovative, and reproducible experiential educational program and mobile lab developed to engage people young and old in the cardiovascular sciences, improve health literacy and awareness of heart-healthy living, and spark curiosity in the science, technology, engineering, and mathematics (STEM) fields. Applied hands-on interactive activities at Heartwheels! events include heart dissection, cardiovascular physiology, and mock flow loops (science), medical devices (technology), instrumentation and sensors (engineering), and calibration and validation methods and models (math). These modules are complementary to school activities and are particularly successful from an educational standpoint because they are fun, interactive, engaging, voluntary, open-ended, not graded or assessed, and can lead participants and their families to develop STEM-positive identities. Primary learning objectives include a broad understanding of cardiovascular anatomy and physiology, advanced technologies and emerging medical devices, the benefits of a heart healthy lifestyle, and to stimulate interest, to build self-confidence, and to help participants envision themselves participating in and making potentially significant contributions to STEM fields. To date, 10,284 attendees of all ages and backgrounds have participated in 47 Heartwheels! events. Excellent programmatic ratings (1-5 scale; 1=poor, 5=excellent), including 91.7% participants self-reporting that it was a fun educational experience and 93.1% reporting that they learned new things, with complimentary verbal and open-ended written feedback, demonstrate the significant impact and value that Heartwheels! and hands-on experiential educational events contribute to our diverse, resource limited, and underserved communities.

Rectifiable Conductive Thermal Diodes Enabling Thermal Circuits with Selectable Operations for Thermal Logic Applications

AbstractThermal logic paves the way to replace electric logic in scenarios where electronic signals are susceptible to interference or traditional electronics cannot be used, however, is still considered a theoretical and numerical stage. Emerging thermal metalmaterials (TMMs) have the potential to enhance thermal information processes. Compared to TMMs with single‐and‐fixed heat transfer capabilities, rectifiable‐TMMs enable thermal circuits to perform selectable operations, but they are also limited by low operating temperatures and narrow temperature biases. Here, macro‐ and experimental thermal diodes with tree‐like eutectic gallium‐indium/printed polylactic‐acid (EGaIn/PPLA) interface, are demonstrated to be capable of extending asymmetric heat transfer difference to 5.81 times in ambient operation, compared with basic EGaIn/PPLA interface with an input temperature bias of 63.7 °C. Given this, basic thermal gates can be constructed through the incorporation of resistors and a pair of diodes working in the same or opposite directions, with the propagation delay time td within 18 min. Compound logic gates can be cascaded by basic gates in the same way as composed Boolean functions, with td within 4 min. Such thermal circuits prove to perform reliably under dynamic ambient conditions, advancing the engineering of devices designed to manipulate thermal energy and process abundant thermal information.

Hybrid nanoparticle array fabricated using injection‐molded nanostructure

AbstractNow that well‐ordered nanoparticles can yield a promising performance in various fields, spatially regular arrangement of particles is a key requirement for nanoparticle‐embedded engineering materials and devices. Here, we demonstrate a feasible, robust method where nanoparticles can be regularly distributed and encapsulated. Polymeric substrates with different sized nanoholes were injection‐molded by controlling mold‐wall temperature in a spatial and temporal manner. A hybrid structure of nanoparticles was constructed by binding quantum dots with metal nanoparticles, and they were filled into the nanoholes using the knife coating process. The morphology of the nanostructure prepared via the molding process and the nanoparticle array was analyzed using a scanning electron microscope and a transmission electron microscope. Fluorescence emission of the hybrid nanostructure was measured. The finding showed that the strategic approach introduced in this study could allow fabrication of hybrid nanoparticle structures with good processability and productivity. © 2024 Society of Chemical Industry.

Experimental evaluation of solar collectors

The purpose of the present work was to investigate the association of two important engineering devices, the two-phase thermosyphon and the solar collector. A cycle to obtain high vacuum was set up to manufacture thermosyphons, which were inserted into evacuated glass tubes to compose the structure of a solar collector prototype. The prototype was operated over a period of eight months, during which two other solar collectors were tested simultaneously for comparison purposes. The other two collectors were purchased on the market, one of which already included the thermosyphons, while the other operated without them. Temperature readings were taken at the manifold inlet and outlet, as well as in the main water supply, and in the storage tank. The temperature data were analyzed and could be condensed into just two 24-hour periods, as they showed reproducible behavior. A calorimeter allowed estimating the amount of stored energy, which in this case used twenty 24 hour periods for analysis. It was concluded that the solar collector that uses the thermosyphon can reach higher temperatures at the manifold outlet, but the storage tank can interfere, causing a decrease in the temperature of the water that reaches the consumer.

Chemical and Heat Treatment for Viral Inactivation in Porcine-Derived Gelatin

BackgroundIt is mandatory to demonstrate the removal or inactivation of potential viral contaminants in the manufacturing processes of pharmaceuticals derived from biomaterials. Porcine-derived gelatin is used in various medical fields, including regenerative medicine, tissue engineering, and medical devices. However, the steps of virus inactivation in the gelatin manufacturing process are poorly defined. In this study we evaluated virus inactivation in two steps of the gelatin manufacturing process.MethodsPig skin (4.5 g), including solid pieces as intermediate products, was spiked with model viruses, including CPV (canine parvovirus), BAV (bovine adenovirus), BPIV3 (bovine parainfluenza type 3), PRV (pseudorabies virus), BReoV3 (bovine reovirus type 3), and PPV (porcine parvovirus), and underwent chemical treatment with alkaline ethanol or heat treatment at 62 °C followed by inoculation in relevant cell cultures. Viral titers in the samples were calculated based on the Behrens-Kärber method.ResultsModel viruses were inactivated at different rates; however, effective inactivation of all model viruses was demonstrated by an LRV (log reduction value) over 4 by both chemical and heat treatment, and chemical treatment demonstrated rapid inactivation compared to heat treatment.ConclusionThe chemical and heat treatment steps exhibited meaningful viral inactivation capacity. They are integrated parts in the extraction and manufacturing process of porcine-derived gelatin, ensuring virus safety for use in medical applications.

Bent zigzag graphene nanoribbons for spintronic applications

Abstract We investigate a spintronic device utilizing bent zigzag graphene nanoribbons (ZGNRs) to explore their spin-dependent electronic and transport properties. Employing a mean-field Hubbard model and the Landauer-Büttiker formalism, we examine the effects of curvature on a large-scale bent ZGNR, revealing a spin-semiconducting phase in the antiferromagnetic ground state. The device comprises a circularly curved nanoribbon connected to two straight ZGNRs, forming a two-terminal, stretchable system. Our findings demonstrate that the spin energy gap and spin-splitting effects in bent ZGNRs are highly tunable via curvature parameters—total rotation, radius, and width. Even minimal curvature induces significant spin-dependent behavior and spin Seebeck coefficient (SSC), resulting in full spin polarization in both the density of states and the transmission coefficient. The degree of spin polarization increases with the bending parameter, leading to enhanced spin-polarized current and a substantial SSC. These results suggest that bent ZGNRs are promising for advancing spintronic applications, particularly in flexible device technologies.

Examination of elementary school students digital literacy levels in terms of different variables

The aim of this study is to examine the digital literacy levels of primary school students according to different variables. The survey model was used to investigate how technology, which has become one of the most important needs of today, affects the digital literacy of primary school students who have experienced distance education. The participants of the study consisted of 100 students studying in a city center located in the Black Sea region of Turkey. The data were obtained by using the personal information form developed by the researchers and the "Digital Literacy" scale developed by Pala and Başıbüyük (2010). In the analysis of the data, percentage, arithmetic mean, gender, independent sample t-test for the variables of availability of technological tools, one-way analysis of variance (ANOVA) was used for the variables of parental education level, place of residence, time spent with technology and family income level. As a result of the research, it was seen that the digital literacy level of the students was at an average level and that the digital literacy of the students showed significance according to the family income level and the availability of internet at home, while there was no significant difference according to variables such as gender, parental education level, and the availability of technological devices. Based on the data of the study, it is recommended to include related courses in the curriculum for the positive development of students' digital literacy.

Strain-Engineered 2D Materials: Challenges, Opportunities, and Future Perspectives.

Strain engineering is a powerful strategy that can strongly influence and tune the intrinsic characteristics of materials by incorporating lattice deformations. Due to atomically thin thickness, 2D materials are excellent candidates for strain engineering as they possess inherent mechanical flexibility and stretchability, which allow them to withstand large strains. The application of strain affects the atomic arrangement in the lattice of 2D material, which modify the electronic band structure. It subsequently tunes the electrical and optical characteristics, thereby enhances the performance and functionalities of the fabricated devices. Recent advances in strain engineering strategies for large-area flexible devices fabricated with 2D materials enable dynamic modulation of device performance. This perspective provides an overview of the strain engineering approaches employed so far for straining 2D materials, reviewing their advantages and disadvantages. The effect of various strains (uniaxial, biaxial, hydrostatic) on the characteristics of 2D material is also discussed, with a particular emphasis on electronic and optical properties. The strain-inducing methods employed for large-area device applications based on 2D materials are summarized. In addition, the future perspectives of strain engineering in functional devices, along with the associated challenges and potential solutions, are also outlined.

Stacking selected polarization switching and phase transition in vdW ferroelectric α-In2Se3 junction devices

The structure and dynamics of ferroelectric domain walls are essential for polarization switching in ferroelectrics, which remains relatively unexplored in two-dimensional ferroelectric α-In2Se3. Interlayer interactions engineering via selecting the stacking order in two-dimensional materials allows modulation of ferroelectric properties. Here, we report stacking-dependent ferroelectric domain walls in 2H and 3R stacked α-In2Se3, elucidating the resistance switching mechanism in ferroelectric semiconductor-metal junction devices. In 3R α-In2Se3, the in-plane movement of out-of-plane ferroelectric domain walls yield a large hysteresis window. Conversely, 2H α-In2Se3 devices favor in-plane domain walls and out-of-plane domain wall motion, producing a small hysteresis window. High electric fields induce a ferro-paraelectric phase transition of In2Se3, where 3R In2Se3 reaches the transition through intralayer atomic gliding, while 2H In2Se3 undergoes a complex process comprising intralayer bond dissociation and interlayer bond reconstruction. Our findings demonstrate tunable ferroelectric properties via stacking configurations, offering an expanded dimension for material engineering in ferroelectric devices.

DC and RF Performance Optimization of Source Pocket Designed Hybrid-Dielectric Vertical Nanowire Tunnel-FET: Low Power Perspective

This article addresses a new source pocket designed hybrid-dielectric vertical nanowire tunnel-FET (SP-HD-VNW-TFET). The existence of a source pocket at the source and channel boundary is shown such that the potential barrier at the tunnel-junction is minimized which causes ON current to rise. This article studied a comparison between a SP-HD-VNW-TFET device and source pocket vertical nanowire tunnel field effect transistor (SP-VNW_TFET). Using a hetero/hybrid-dielectric material boosts the electric field, resulting in higher tunneling current (1.72 × 10−6 A μm−1). The device has undergone detailed investigation of both DC and AC characteristics like On-current, Off-current, ION/IOFF, Subthreshold-swing, VT, gm, fT, GWB, and TFP. Source Pocket engineering and Hybrid dielectric inclusion increase device properties, including on-current and subthreshold swing (SS). The device’s electrical properties have been evaluated and compared using the Sentaurus TCAD Tool.

Utilization of the use of technological devices in delivering communication information in the learning process

The development of increasingly sophisticated technology today brings education to participate in using the features available in today’s media such as the transition from face-to-face learning communication in schools to face-to-face assisted by technology such as laptops, tablets, cellphones and other multimedia. Technology currently provides innovation in the learning process both from home and from school. However, there are still many teachers and students who have not utilized technology such as laptops, tablets, cellphones and other multimedia in the learning process. The purpose of the study was to analyze the benefits and relationships of the four main variables of communication assessment elements with digital devices. The research method used was quantitative with a sample of 148 teachers randomly selected from schools that use technology in the learning process. Data collection techniques with instruments. The instruments used were four indicator instruments, namely technology from laptops, tablets, cellphones and other multimedia. Data analysis techniques with descriptive statistics using SPSS version 26.0 calculated the mean, standard deviation, and correlation test. The results of the study found that the four indicators had high reliability and the four indicators had significant utilization, were mutually positive and had a high relationship with each other. The conclusion is that the four technological devices are good for use in digital communication during the learning process and laptops and tablets are more recommended in this study.

High-strength polyvinyl alcohol/gelatin/LiCl dual-network conductive hydrogel for multifunctional sensors and supercapacitors

The synthesis of conductive hydrogels with high mechanical strength, toughness, optimal fracture growth rate and the capability to detect diverse human body movements poses a significant challenge in the realm of flexible electronics. In this study, a one-pot technique utilized effectively to fabricate conductive materials by doping LiCl into a mixture of polyvinyl alcohol (PVA) and gelatin. The PVA/gelatin/LiCl0.3(PGL) conductive hydrogel demonstrates exceptional robustness, flexibility, and resistance to deformation, enabling the monitoring of various physiological signals such as temperature and humidity. Additionally, the PGL demonstrates exceptional elongation properties (up to 1111.32 %), high lifting capacity (up to 25 kg), resistance to deformation, and sustained stability of peak signals even after 300 cycles at 50 % strain. The hydrogel electrolyte exhibits a conductivity of 2.114 S/m at 25 °C and a specific capacitance of up to 48.75 F/g, along with favorable mechanical and electrochemical characteristics. These findings suggest that the PVA/gelatin/LiCl0.3 hydrogel supercapacitor (PGLSC) conductive hydrogel shows significant potential for integration into flexible electronics and wearable technology devices.

Analyzing antimicrobial activity of ZnO/FTO, Sn-Cu-doped ZnO/FTO thin films: Production and characterizations.

In the developing field of nanotechnology, ZnO (zinc oxide) based semiconductor samples have emerged as the foremost choice due to their immense potential for advancing the development of cutting-edge nanodevices. Due to its excellent chemical stability, low cost, and non-toxicity to biological systems, it is also utilized in various investigations. In this study, the successive ionic layer adsorption and reaction (SILAR) method was used to generate FTO (fluorine-doped tin oxide)/ZnO, and tin (Sn)-copper (Cu)-doped ZnO thin films at varying concentrations on FTO substrates. After being stacked 40 times in varying concentrations on the FTO substrate, FTO/ZnO thin films and Sn-Cu-doped thin films were annealed at 300°C. Using Scanning Electron Microscopy (SEM) Energy Dispersive Spectroscopy-(EDS), the agar diffusion test, and the viability cell counting method, the minimum inhibitory concentration, structural properties, surface morphology, antibacterial properties, bacterial adhesion, and survival organism count of FTO/ZnO thin films and Sn-Cu-doped thin films were investigated. Both doped and FTO/ZnO films with varying Sn-Cu concentrations expanded harmonically on the FTO substrate, according to the SEM-EDS investigation. The doping concentration affected their morphological properties, causing changes depending on the doping level. Antibacterial activity was observed in the powder metals, but no antibacterial activity was found in the thin film form. The highest adhesion rate of bacterial organisms on the produced samples was observed when the FTO/ZnO/Sn-Cu doping rate was 1%. In addition, the lowest adhesion rate was observed when the FTO/ZnO/Sn-Cu additive ratio was 3%. RESEARCH HIGHLIGHTS: ZnO based semiconductors highlight significant potential in advancing nanodevice technology due to their chemical stability, cost-effectiveness, and biocompatibility. Employing the SILAR method, the study innovatively fabricates FTO/ZnO and Sn-Cu-doped ZnO thin films on FTO substrates, exploring a novel approach in semiconductor manufacturing. Post annealing at 300°C, the research examines the structural and surface morphological changes in the films, contributing to the understanding of semiconductor behavior under varying conditions. The study delves into the antibacterial properties of ZnO thin films, offering insights into the potential biomedical applications of these materials. SEM-EDS analysis reveals that doping concentrations crucially influence the morphological properties of ZnO thin films, shedding light on the optimization of semiconductor performance. Findings indicate a specific doping rate (1% Sn-Cu) enhances bacterial adhesion, while a 3% additive ratio minimizes it, suggesting implications for biomedical device engineering and antibacterial surface design.

Discussion about Testing Scheme of Intelligent Medical Devices

Intelligent medical devices are flourishing with the deep integration of modern information and artificial intelligence technologies into healthcare. Testing is an important means of performance evaluation and quality control for intelligent medical devices. Compared with traditional medical devices, the testing methods and technologies of intelligent medical devices are still immature, and need active research to promote the progress in this area. Intelligent medical devices are classified according to their characteristics as artificial intelligence medical devices in the form of software and medical robots based on a general discussion of their development. The medical-device Internet of Things (IoT) system has also been included due to its close relation to the construction of smart hospitals. For each type of intelligent medical device, testing indexes and testing plans are discussed. It is suggested that specific test rules should be further developed for various specific devices. Besides, the evaluation method of complex intelligent systems should be introduced and real-world data should be used for evaluation. This paper aims to accelerate the development of intelligent medical device testing, laying the foundation for quality control and performance evaluation of intelligent medical devices.

What Is to Be Expected from Heterogeneous Catalysis in the Pipeline to Circular Economy?

Modern society requires a change in the philosophy of doing science, which faces the enormous challenge of being compatible with the new sustainability principles. Inorganic chemistry holds the keys to accelerate the transition given that most chemical processes or technology devices rely on the use or integration of inorganic materials. In particular, heterogeneous catalysis has a central role in promoting the transition from a linear economy to a circular one. To accomplish this, it is imperative that the modern schemes for catalysis will adopt a holistic approach based on sensible choice of raw materials, reliance on clean energy inputs and establishment of a robust framework of resource use and recovery. Some of these concepts are analysed here and discussed in Ref. [to a few selected examples.

Analysis of the Effectiveness of Taser in Police Intervention and Overview of the Main Causes of Failure

An inappropriately chosen tactical procedure and means during a police intervention against highly dangerous subjects may lead to an escalation of the conflict and to further threats to the interveners and to the subject against whom the intervention is conducted. The main objective of this article is to analyse the effectiveness of the technical device Taser, which uses an electrical discharge to temporarily incapacitate a human subject, identify the main causes of failure of it, and its implications in practice at the incident level. The paper is based on the presentation of current scientific evidence in available electronic databases (Web of Science, Scopus; using keyword taser), and the data are compiled into a clear graphical form through the principles of the Fault Tree Analysis (FTA). A set of potential failure causes was identified from the human factor, the role of technology, and environmental influences. The taser was found to be a conditionally effective technological device with a wide and difficult to determine range of effectiveness depending on the method chosen. The findings have implications for training and education with a focus on minimising the risks of service intervention in terms of the effectiveness of this type of law enforcement agent.

Research on Device and Sensing Technology for Precision Seeding of Potato

The potato industry is crucial to the development of the agricultural economy, and mechanized seeding is an effective aid to its modernization. Due to the metering devices having different sizes and structures, and even control, operation of sudden instability and other characteristics, and the complexity and variability of the farmland environment and other reasons, the mechanical sowing process may be affected by internal and external random and unpredictable factors, thus causing seed potato leakage, reseeding, and other phenomena and resulting in a decline in the quality of potato sowing brought about by the cascade effect: the quality and yield decline, precision sowing has become the modern potato production in the problem of modern potato production needs to be solved. This paper reviews the potato planter around the seeding quality of single seeding, plant spacing, depth and other directions of device optimization and digital sensing technology innovation involved, which single seeding direction from a variety of metering devices and the use of other sowing methods of potato planter detection, replanting, metering and other parts of the entry, and the introduction of the other field crops crop related research to provide a more comprehensive perspective. The advantages and disadvantages of the related research were compared and the existing problems were analyzed, and the future development direction of potato precision sowing technology was prospected.

Approaches for white organic light-emitting diode via solution-processed blue and yellow TADF emitters: Charge balance and host-guest interactions in a single emission layer

[Display omitted] Although OLEDs are widely employed nowadays for display technology devices, their application for room-lighting illumination remains a challenge due to the cost-effectiveness issues, mainly related to device fabrication. In this sense, the present study investigates the optimization of blue-emitting TADF (DMOC-DPS) and yellow-emitting TADF (TXO-TPA) compounds in solution-processed OLEDs to achieve efficient white light emission in a two-organic layer device. Four different host materials were studied, aiming to balance the charge mobility of holes and electrons. The host materials used include (in %wt.) a 1:1 mixture of mCP and DPEPO (HOST1), a 3:2 mixture of PVK and DPEPO (HOST2), a 3:2 mixture of PVK and mCP (HOST3), and a 3:2 mixture of PVK and butyl-PBD (HOST4). The experimental results obtained from the solution-processed OLEDs indicate that DMOC-DPS is predominantly a hole transport material, and hosts with predominantly n-type character, such as HOST1 and HOST4, resulting in the most efficient white-OLEDs by the most balanced charge mobility. With structure optimization, WOLEDs achieved 6.43 % EQE with a brightness of 2621 cd/m2 (not integrated) and 6.06 % EQE with a brightness of 1986 cd/m2 for HOST4 and HOST1, respectively. The emission characteristics were influenced by host materials characteristics, with blue and yellow emissions being fine-tuned to produce complementary colors. This study highlights the critical role of charge mobility balance in the emissive layer and demonstrates the potential of independently optimizing blue and yellow TADF components for high-performance WOLEDs suitable for indoor lighting applications.

Mechanical thrombectomy failure in anterior and posterior circulation stroke: current results from a high-volume comprehensive center.

Mechanical thrombectomy (MT) is an established therapy for acute ischemic stroke (AIS), but recanalization is not always achieved. Common reasons are inadequate removal at the thrombus site and difficulties with the access route. In order to identify risk factors for MT failure we conducted a retrospective study on a high-volume comprehensive stroke center. Evaluation of 552 thrombectomies (2019-23; anterior and posterior circulation, direct aspiration +/- stent retriever [SR]). MT failures (= modified Thrombolysis in Cerebral Infarction score 0 or 1) were analyzed for age, sex, pre- and post-MT modified Rankin Scale, bridging intravenous thrombolysis (IVT), occlusion site (anterior / posterior circulation, proximal / distal), the Kaesmacher classification and time trend results. MT failure occurred in 56 patients (10.1%; median age 76; 53.6% female). Nineteen (33.9%) patients received IVT (p = 0.326). Logistic regression analysis did not show a significant association of age, sex or occlusion site with MT failure (p = 0.165, p = 0.738, p = 0.838). Distal MT generally demonstrated lower success rates (p < 0.01). According to the Kaesmacher classification SR failure was the most frequent cause of MT failure (category 2B: 48%, p < 0.001). Time trend analysis suggests improving recanalization rates in the further course (4 times in year-on-year comparison; p < 0.01). MT failure occurs in AIS treatment, even in high-volume centers and occurs more frequently in distal occlusions. Improvements in device technology, particularly SR, and ongoing refinements in access route selection offer the prospect of better outcomes in the future.

Fog Computing for Artificial Intelligence Digital Textbooks: Educational Scaffolding and Security and Privacy Challenges

ABSTRACTDigital textbooks (DTs) have evolved from DT 1.0, which simply converted paper textbooks to PDF format, to DT 2.0, which provides various multimedia content, for example, video and audio content. DTs have now advanced to DT 3.0, which enhances learner engagement through gamification and simulations. Recently, with the advancement of cloud computing technology and digital devices, for example, tablets, DT 4.0, which supports personalised learning through artificial intelligence (AI) tutors and chatbots, has been realised. South Korea is actively implementing a policy to distribute artificial intelligence–based DTs, equivalent to DT 4.0, to all schools under national leadership. For artificial intelligence–based DTs (AIDTs) in South Korea to develop into a sustainable education system, reliance on cloud computing alone is insufficient. It is also necessary to build layers of fog computing and edge computing from the initial stage. There are concerns that AIDTs may exacerbate the learning gap because they are more likely to be utilised actively by high‐performing students with established self‐directed learning habits rather than struggling students. Thus, it is essential to enhance usage monitoring and explore strategies that provide educational scaffolding to prevent differences in the level of AIDT utilisation from leading to a widening learning gap.