Complex Devices Research Articles

Trace Dual-Crosslinkable Additives Enable Direct Microlithography for Enhanced Organic Electrochemical Transistors.

Similar to silicon-based electronics, the implementation of micro/nano-patterning to facilitate complex device architectures and high-density integration is crucial to the development of organic electronics. Among various patterning techniques, direct microlithography (DML) is highly applicable and extensively adopted in organic electronics, such as organic electrochemical transistors (OECTs). However, conventional DML often requires high crosslinker concentrations, leading to compromised electrical performance. To address this challenge, a novel strategy is developed that combines supramolecular and covalent interactions by incorporating a polyrotaxane supramolecular crosslinker (PR) into poly(benzodifurandione) (PBFDO). The PR forms a hydrogen bonding network with PBFDO and undergoes UV-triggered covalent crosslinking among its molecules, providing solvent resistance even at trace loading levels (<0.1 wt%). This approach enables precise patterning of PBFDO with feature sizes below 1µm while preserving high electrical performance. Notably, PR also serves as a performance enhancer, promoting molecular ordering and ionic conduction within PBFDO. OECTs fabricated with PR-crosslinked PBFDO exhibit about one-order-of-magnitude increase in ON/OFF ratio, a 42% increase in µC* (reaching 2460Fcm-1V-1s-1), and elevated operational stability compared to pristine ones. This multifunctional crosslinker offers a scalable solution for high-performance, high-density organic electronics and opens new avenues for supramolecular chemistry applications in this field.

Mechanical circulatory support for complex, high-risk percutaneous coronary intervention.

The evidence base evaluating the use of mechanical circulatory support (MCS) devices in complex, high-risk percutaneous coronary intervention is evolving from a small number of randomised clinical trials to incorporate an amassing body of real-world data. Due to both the growing incidence of the procedures and the limitations of the evidence, there is wide variability in the use of MCS, and the benefits are actively debated. The goal of this review is to perform an integrated analysis of randomised and non-randomised studies which have informed clinical and regulatory decision-making in contemporary clinical practice. In addition, we describe forthcoming studies that have been specifically designed to advance the field and resolve ongoing controversies that remain unanswered for this complex, high-risk patient population.

Multifunctional UV photodetect-memristors based on area selective fabricated Ga2S3/graphene/GaN van der Waals heterojunctions.

Multifunctional devices based on van der Waals heterojunctions have drawn significant attention owing to their portable size, low power consumption and various application scenarios. However, high fabrication equipment requirements, complex device structures and limited operating conditions hinder their potential value. Herein, multifunctional UV photodetect-memristors based on Ga2S3/graphene/GaN van der Waals heterojunctions via area selective deposition have been proposed for the first time. The Ga2S3/graphene/GaN heterojunctions are firstly grown via area selective deposition (ASD) without a mask plate or lithography process. And the corresponding molecular dynamics (MD) and density functional theory (DFT) simulation further confirmed its feasibility and physical properties. Subsequently, multifunctional devices based on Ga2S3/graphene/GaN heterojunctions are fabricated accordingly, and exhibit ultrafast (<80 μs) response at 0 V and stable, highly sensitive (1150.4 A W-1) memory features at 3 V. Here, the huge hole barriers formed on the two edges of graphene set the foundation of trapping and detecting light-induced carriers. Afterwards, handwriting numeral recognition tasks are carried out based on the performance extracted from the device and a simplified noise filtering and improved recognition accuracy system is proposed, confirming its application potential in the artificial intelligence area. This study proposes a practical way to grow large-size 2D materials selectively, shows the valuable application potential of p-g-n heterojunctions in various application fields, and expands an innovative path of device development in the post-Moorish era.

Monolithic on-chip integration of micro-thin film thermocouples on multifinger gallium oxide MOSFETs

Gallium oxide (Ga2O3), with its ultra-wide bandgap (&amp;gt;4.5 eV), is a key material for the next-generation power electronics due to its high breakdown voltage and efficient power-switching capabilities. Multifinger (MF) Ga2O3 MOSFETS, designed to enhance current handling and thermal management, experience significant self-heating effects that can lead to localized hotspots, thermal runaway, and reduced device reliability. Accurate thermal characterization is therefore critical to ensure the reliable operation and longevity of such devices. Conventional methods, such as thermoreflectance imaging, Raman thermometry, and infrared thermography, are limited by complex setups, slow response times, resolution constraints, and cost, making them less practical for real-time, on-chip applications. On-chip thermal characterization directly at the active regions of the device provides an unparalleled opportunity to overcome these limitations by capturing localized temperature variations during operation. In this study, we demonstrate the integration of micro-thin film thermocouples (micro-TFTCs) onto multifinger Ga2O3 MOSFETs for precise, real-time, and localized thermal monitoring. The sensors captured temperature variations across different gate fingers, with the measured maximum channel temperature reaching 40.5 °C under peak power dissipation. Predicted thermal behavior under high power densities shows temperatures rising to approximately 80 °C at 5 W/mm2, illustrating the thermal challenges faced by Ga2O3 devices. This work demonstrates that micro-TFTCs are not only compatible with complex device architectures but also highly effective for localized thermal characterization, making them a promising tool for improving the thermal management and reliability of Ga2O3-based power electronics.

Reliable, efficient, and scalable photonic inverse design empowered by physics-inspired deep learning

Abstract On-chip computing metasystems composed of multilayer metamaterials have the potential to become the next-generation computing hardware endowed with light-speed processing ability and low power consumption but are hindered by current design paradigms. To date, neither numerical nor analytical methods can balance efficiency and accuracy of the design process. To address the issue, a physics-inspired deep learning architecture termed electromagnetic neural network (EMNN) is proposed to enable an efficient, reliable, and flexible paradigm of inverse design. EMNN consists of two parts: EMNN Netlet serves as a local electromagnetic field solver; Huygens–Fresnel Stitch is used for concatenating local predictions. It can make direct, rapid, and accurate predictions of full-wave field based on input fields of arbitrary variations and structures of nonfixed size. With the aid of EMNN, we design computing metasystems that can perform handwritten digit recognition and speech command recognition. EMNN increases the design speed by 17,000 times than that of the analytical model and reduces the modeling error by two orders of magnitude compared to the numerical model. By integrating deep learning techniques with fundamental physical principle, EMNN manifests great interpretability and generalization ability beyond conventional networks. Additionally, it innovates a design paradigm that guarantees both high efficiency and high fidelity. Furthermore, the flexible paradigm can be applicable to the unprecedentedly challenging design of large-scale, high-degree-of-freedom, and functionally complex devices embodied by on-chip optical diffractive networks, so as to further promote the development of computing metasystems.

Wearable gesture control design for unmanned aerial vehicle based on multi-sensor fusion

Abstract Traditional bulky and complex control devices such as remote control and ground station cannot meet the requirement of fast and flexible control of unmanned aerial vehicles (UAVs) in complex environments. Therefore, a data glove based on multi-sensor fusion is designed in this paper. In order to achieve the goal of gesture control of UAVs, the method can accurately recognize various gestures and convert them into corresponding UAV control commands. First, the wireless data glove fuses flexible fiber optic sensors and inertial sensors to construct a gesture dataset. Then, the trained neural network model is deployed to the STM32 microcontroller-based data glove for real-time gesture recognition, in which the convolutional neural network-Attention mechanism (CNN-Attention) network is used for static gesture recognition, and the convolutional neural network-bidirectional long and short-term memory (CNN-Bi-LSTM) network is used for dynamic gesture recognition. Finally, the gestures are converted into control commands and sent to the vehicle terminal to control the UAV. Through the UAV simulation test on the simulation platform, the average recognition accuracy of 32 static gestures reaches 99.7%, and the average recognition accuracy of 13 dynamic gestures reaches 99.9%, which indicates that the system’s gesture recognition effect is perfect. The task test in the scene constructed in the real environment shows that the UAV can respond to the gestures quickly, and the method proposed in this paper can realize the real-time stable control of the UAV on the terminal side.

Development of an organizational and economic mechanism for the implementation of a product selection recommendation system

The study includes an analysis of existing problems that arise in the process of choosing a product, including complex technical devices. Based on the analysis, the paper proposes an organizational and economic mechanism that allows for the introduction of a recommendation system into the activities of an online store, which simplifies the process of choosing a product for the user. This tool will provide the organization with a competitive advantage and will increase website traffic, sales conversion and customer loyalty, which is especially relevant given the growing competition in online trading.

On Demand Copper Electrochemical Deposition on Laser Induced Graphene for Flexible Electronics.

The rapid development of flexible electronics necessitates simplified processes that integrate heterogeneous materials and structures. In this study, laser engraving is combined with electrochemical deposition (ECD) to directly fabricate various micro/nano-structured components and flexible electronic circuits. A theoretical framework and simulation model are developed to design the on-demand ECD on laser induced graphene (LIG), enabling the generation of multi-scale copper (Cu) materials with controllable oxidation states. The Cu-LIG composites exhibit high surface quality and reliability, meeting the requirements of flexible circuits. The study fabricates and characterizes multilayer circuits and complex functional devices, including electrochemical sensors, thin-film heaters, and wireless humidity sensors, to showcase the versatility of the LIG-ECD process. This approach can be extended to various polymer and metal deposition processes, paving the way for the development of high-performance flexible electronic devices.

Accelerated Modeling of Transients in Electromagnetic Devices Based on Magnetoelectric Substitution Circuits

During switching in electrical systems, transient electromagnetic processes occur. The resulting dangerous current surges are best studied by computer simulation. However, the time required for computer simulation of such processes is significant for complex electromagnetic devices, which is undesirable. The use of spectral methods can significantly speed up the calculation of transient processes and ensure high accuracy. At present, we are not aware of publications showing the use of spectral methods for calculating transient processes in electromagnetic devices containing ferromagnetic cores. The purpose of the work: The objective of this work is to develop a highly effective method for calculating electromagnetic transient processes in a coil with a ferromagnetic magnetic core connected to a voltage source. The method involves the use of nonlinear magnetoelectric substitution circuits for electromagnetic devices and a spectral method for representing solution functions using orthogonal polynomials. Additionally, a schematic model for applying the spectral method is developed. Obtained Results: A method for calculating transients in magnetoelectric circuits based on approximating solution functions with algebraic orthogonal polynomial series is proposed and studied. This helps to transform integro-differential state equations into linear algebraic equations for the representations of the solution functions. The developed schematic model simplifies the use of the calculation method. Representations of true electric and magnetic current functions are interpreted as direct currents in the proposed substitution circuit. Based on these methods, a computer program is created to simulate transient processes in a magnetoelectric circuit. Comparing the application of various polynomials enables the selection of the optimal polynomial type. The proposed method has advantages over other known methods. These advantages include reducing the simulation time for electromagnetic transient processes (in the examples considered, by more than 12 times than calculations using the implicit Euler method) while ensuring the same level of accuracy. The simulation of processes over a long time interval demonstrate error reduction and stabilization. This indicates the potential of the proposed method for simulating processes in more complex electromagnetic devices, (for example, transformers).

A method for uniform upgrading of isolated bridges with complex root devices

An experimentally proved method for efficient seismic upgrading of isolated bridges exposed to very strong multi-directional near-field and far-field earthquakes is presented in this paper. The advanced capability of the upgraded bridge system was achieved by application of the developed uniform complex root (CR) energy dissipation devices. The new uniform complex root (UCR) bridge system was fully validated based on seismic tests on experimental models and analytical response simulation studies. The UCR system integrates the advances of seismic isolation and energy dissipation and represents an advanced technical solution for efficient protection of bridges located in seismic areas of the highest seismicity. The tested large-scale model of the UCR bridge system had double spherical rolling seismic bearings (DSRSB) as seismic isolation devices, while qualitative improvement of the seismic performances was achieved through the use of the created uniform CR energy dissipation devices. Extensive seismic testing of the UCR bridge model was conducted under simulated effects of near-field and far-field earthquakes, respectively.

Clinical trials for implantable neural prostheses: understanding the ethical and technical requirements.

Neuroprosthetics research has entered a stage in which animal models and proof-of-concept studies are translated into clinical applications, often combining implants with artificial intelligence techniques. This new phase raises the question of how clinical trials should be designed to scientifically and ethically address the unique features of neural prostheses. Neural prostheses are complex cyberbiological devices able to acquire and process data; hence, their assessment is not reducible to only third-party safety and efficacy evaluations as in pharmacological research. In addition, assessment of neural prostheses requires a causal understanding of their mechanisms, and scrutiny of their information security and legal liability standards. Some neural prostheses affect not only human behaviour, but also psychological faculties such as consciousness, cognition, and affective states. In this Viewpoint, we argue that the technological novelty of neural prostheses could generate challenges for technology assessment, clinical validation, and research ethics oversight. To this end, we identify a set of methodological and research ethics challenges specific to this medical technology innovation. We provide insights into relevant ethical guidelines and assess whether oversight mechanisms are well equipped to ensure adequate clinical and ethical use. Finally, we outline patient-centred research ethics requirements for clinical trials involving implantable neural prostheses.

Short-Time Preamplification-Assisted One-Pot CRISPR Nucleic Acid Detection Method with Portable Self-Heating Equipment for Point-of-Care Diagnosis.

Infectious diseases, especially respiratory infections, have been significant threats to human health. Therefore, it is essential to develop rapid, portable, and highly sensitive diagnostic methods for their control. Herein, a short-time preamplified, one-pot clustered regularly interspaced short palindromic repeats (CRISPR) nucleic acid detection method (SPOC) is developed by combining the rapid recombinase polymerase amplification (RPA) with CRISPR-Cas12a to reduce the mutual interference and achieve facile and rapid molecular diagnosis. SPOC can reduce the detection time and stably detect up to 1 copy/μL of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA without affecting the detection sensitivity. A highly sensitive one-pot assay integrated with reverse transcription RPA is achieved by wrapping paraffin with a specific melting point on the lyophilized CRISPR reagent surface. A self-heating pack is designed based on thermodynamic principles to melt the paraffin and release CRISPR reagents, enabling low-cost and time-saving detection. Notably, the designed system, coupled with RNA extraction-free technology, can achieve "sample-in-answer-out" detection of the SARS-CoV-2 Orf1ab gene within 22 min using smartphone imaging. The developed assay is validated on 12 clinical samples, and the results 100% correlate with real-time polymerase chain reaction. SPOC is time-saving, is easy to operate, and can eliminate centrifugal and complex hardware devices, satisfying the demand for point-of-care diagnostics in resource-constrained settings.

“One heart - seven leads: a case report of complex cardiac device therapy in a patient with chemotherapy - induced toxic cardiomyopathy”

“One heart - seven leads: a case report of complex cardiac device therapy in a patient with chemotherapy - induced toxic cardiomyopathy”

Utilities Associated with the Treatment of Growth Hormone Deficiency (GHD): A Time Trade-off (TTO) Study in the UK and Canada.

Growth hormone deficiency (GHD) causes decreased growth rate in children, resulting in short stature in childhood and adulthood. Daily subcutaneous injections with growth hormone (GH) have been standard treatment. Newer weekly GH formulations now exist. This study estimates utilities associated with GHD treatment for both people with the disease and caregivers by employing time trade-off (TTO) methodology. Three online surveys were conducted amongst the general population in the UK and Canada. Based on a pilot, data collection was conducted in two surveys only (Survey A and Survey B). In Survey A, adults aged ≥18 years evaluated health states as if they were receiving injections themselves. In Survey B, adults with a child <15 years evaluated health states as if they were administering injections to a child. The surveys assessed device complexity, injection frequency, injection pain, needle visibility and storage possibilities. 2026 and 2028 respondents completed Survey A and Survey B, respectively. Of these, 1782 respondents and 1678 respondents were valid for inclusion. Avoiding weekly injection pain was associated with a significant utility gain of 0.030 (95% CI 0.026-0.035, p<0.001) in Survey A and 0.044 (95% CI 0.038-0.051, p<0.001) in Survey B. Additionally, less complex injection devices and lower injection frequencies had a significant impact in both Survey A (0.020, 95% CI 0.016-0.025, p<0.001; 0.009, 95% CI 0.005-0.014, p<0.001) and Survey B (0.008, 95% CI 0.002-0.014, p=0.006; 0.009, 95% CI 0.003-0.014, p=0.003). Several aspects are associated with a significant impact on utilities for people with GHD and potential caregivers. Treatment options without injection pain, a time-consuming and complex injection process and daily injections are expected to result in higher health-related quality of life. These results may inform future economic evaluations and treatment choices.

Blister test to measure the out-of-plane shear modulus of few-layer graphene.

We measure the out-of-plane shear modulus of few-layer graphene (FLG) by a blister test. During the test, we employed a monolayer molybdenum disulfide (MoS2) membrane stacked onto FLG wells to facilitate the separation of FLG from the silicon oxide (SiOx) substrate. Using the deflection profile of the blister, we determine an average shear modulus G of 0.97 ± 0.15 GPa, and a free energy model incorporating the interfacial shear force is developed to calculate the adhesion energy between FLG and SiOx substrate. The experimental protocol can be extended to other two-dimensional (2D) materials and layered structures (LS) made from other materials (WS2, hBN, etc.) to characterize their interlayer interactions. These results provide valuable insight into the mechanics of 2D nano devices which is important in designing more complex flexible electronic devices and nanoelectromechanical systems.

Feasibility and Safety of Distal Radial Artery Access with Recanalization of a Chronic Radial Artery Occlusion for Subsequent Coronary Angiography and Intervention.

This study aims to verify the feasibility and safety of percutaneous coronary intervention (PCI) after a distal transradial approach (dTRA) with radial artery occlusion (RAO) recanalization. Between July 2018 and January 2022, 30 patients underwent PCI following attempted RAO recanalization via dTRA. Among these cases, the target radial arteries could not be recanalized in five patients, necessitating alternative vascular access. The remaining 25 patients with successful RAO recanalization were divided into a standard group (n = 19) and tough group (n = 6), the latter requiring more than 10 minutes and complex techniques and devices for recanalization. The procedural success rate was 96.7%, with vascular access-site complications occurring in 20% of the cases, including five perforations easily managed with prolonged balloon inflation and one pseudoaneurysm without flow limitation. In the tough group, no significant increase in procedural complications, access-site vascular complications, or total major adverse cardiac and cerebrovascular events was observed. However, Doppler ultrasound one month later for the recanalized radial artery revealed a significantly higher rate of severe stenosis and re-occlusion at 100% compared to 10% in the standard group, as supported by receiver operating characteristic curve analysis. The feasibility and safety of PCI following RAO recanalization via dTRA were acceptable. We propose a 10-minute threshold to differentiate between standard and tough groups during RAO recanalization. Given the uncertainty of long-term patency in recanalized RAs, the primary goal in tough cases is to ensure the guide catheter reaches the ascending aorta for subsequent PCI.

Large-scale acoustic single cell trapping and selective releasing.

Recent advancements in single-cell analysis have underscored the need for precise isolation and manipulation of individual cells. Traditional techniques for single-cell manipulation are often limited by the number of cells that can be parallel trapped and processed and usually require complex devices or instruments to operate. Here, we introduce an acoustic microfluidic platform that efficiently traps and selectively releases individual cells using spherical air cavities embedded in a polydimethylsiloxane (PDMS) substrate for large scale manipulation. Our device utilizes the principle of acoustic impedance mismatches to generate near-field acoustic potential gradients that create trapping sites for single cells. These single cell traps can be selectively disabled by illuminating a near-infrared laser pulse, allowing targeted release of trapped cells. This method ensures minimal impact on cell viability and proliferation, making it ideal for downstream single-cell analysis. Experimental results demonstrate our platform's capability to trap and release synthetic microparticles and biological cells with high efficiency and biocompatibility. Our device can handle a wide range of cell sizes (8-30 μm) across a large active manipulation area of 1 cm2 with 20 000 single-cell traps, providing a versatile and robust platform for single-cell applications. This acoustic microfluidic platform offers a cost-effective and practical method for large scale single-cell trapping and selective releasing with potential applications in genomics, proteomics, and other fields requiring precise single-cell manipulation.

Cellulose nanocrystal composite films for contactless moisture-electric conversion.

The ability to convert moisture signals into electrical signals through contactless control underpins a wide range of applications, including health monitoring, disaster warning, and energy harvesting. Despite its potential, the effective utilization of low-grade energy remains challenging, as it often requires complex device architectures that limit scalability and integration, particularly in wearable technologies. Here, we present a soft, flexible moisture-electric converter made from cellulose nanocrystals and polyvinyl alcohol composite films, designed for a novel touchless interactive platform. The device autonomously generates an electric output voltage of 200-700 mV in response to ambient moisture variations without requiring an external energy source. Its design, featuring a soft-adhered conductive carbon strip coupled with the composite film, provides high flexibility and portability. This configuration facilitates the creation of a non-contact control interface that seamlessly interacts with biological moisture from the human body, demonstrated by a mask that detects breathing conditions and a panel that measures contact distance. These advancements offer a promising pathway for developing flexible, intelligent electronic devices for wearable and touchless technologies.

High photodetector responsivity and weak light detection in Manganese doped lead-free Low dimensional perovskite

Photodetectors are optoelectronic devices commonly used in communication and sensing systems. Currently, commercial photodetectors using silicon and other inorganic semiconductors demonstrate high performance but are expensive, demand complex device manufacturing,...

Methacrylated poly(glycerol sebacate) as a photocurable, biocompatible, and biodegradable polymer with tunable degradation and drug release kinetics.

Poly(glycerol sebacate) (PGS) is a biodegradable, elastomeric polymer that has been explored for applications including tissue engineering, drug delivery, and wound repair. Despite its promise, its biomedical utility is limited by its rapid, and largely fixed, degradation rate. Additionally, its preparation requires prolonged curing at high temperatures, rendering it incompatible with heat-sensitive molecules, complex device geometries, and high-throughput production. In this study, we synthesized methacrylated PGS (PGS-M), imparting the ability to rapidly photocross-link the polymer. Increasing the degree of methacrylation was found to slow PGS-M degradation; PGS-M (5.5kDa) disks with 21% methacrylation lost 40.1 ± 11.8% of their mass over 11 weeks in vivo whereas 47% methacrylated disks lost just 14.3 ± 1.4% of their mass over the period. Daunorubicin release from PGS-M occurred in a linear fashion without a substantial initial burst. Further, increasing the degree of methacrylation extended the release of encapsulated drug. After 60 days, 21%, 27%, and 47% methacrylated disks with the same drug loading (w/w) released 56.8 ± 5.4%, 15.1 ± 0.4%, and 15.4 ± 0.3% of encapsulated drug, respectively. Importantly, the 27% and 47% methacrylated disks consistently released ~ 0.25% (w/w) of encapsulated drug per day with no burst release. Histological evaluation also suggested that PGS-M is biocompatible, eliciting limited inflammation and fibrous encapsulation when implanted subcutaneously. This report presents the first long-term in vitro studies and first in vivo studies using PGS-M and demonstrates the ability to tune PGS-M degradation rate, use PGS-M to encapsulate drug, and obtain sustained drug release over months.