Development Of Devices Research Articles

The association between gender and industry payments to minimally invasive surgeons.

It is unknown if there are differential industry payments to surgeons based on gender. This study aims to examine differences by gender for industry relations with minimally invasive surgeons, using speakers at the SAGES Annual Meeting as a proxy for key thought leaders in minimally invasive surgery. We queried the Open Payments Database for payments made to US speakers from the 2023 SAGES meeting. All payments from the prior fiscal year prior were collected. The National Provider Identity (NPI) Registry was cross-referenced to determine surgeon's self-reported gender. Industry sponsors were analyzed based on differences in payments made. A total of 305 speakers were assessed, with 175 (57.4%) males and 130 (42.6%) females. Of the 305 speakers, 246 were listed in the OPD. There were 145/175 (82.8%) males who were received general payments, compared to 101/130 (77.6%) females (p = 0.326). The total amount of industry payments was $2,894,287 for males and $1,539,481 for females. Median payments were 2.8X higher for males ($4657, IQR $422-$15,798) than females ($1651, IQR $299-$9005) (p = 0.05). Despite efforts to decrease gender bias in surgery, there remains a significant and substantial difference in payments towards male and female surgeons via industry relationships. This has potential downstream effects on career development, consulting and research opportunities, and development of new devices.

Accurate Determination of the Uniaxial Complex Refractive Index and the Optical Band Gap of Polymer Thin Films to Correlate Their Absorption Strength and Onset of Absorption.

The advanced development of optoelectronic devices requires a methodical knowledge of the fundamental material properties of the key active components. Systematic investigations and correlations of such basic optical properties can lead to new insights for the design of more potent materials. In this perspective, we provide a systematic overview of the uniaxial anisotropic complex refractive indices and the absorption coefficients obtained by ellipsometry as well as the optical band gap energies derived from Tauc plots of six selected solution-processed polymer thin films. While the optical band gap energies are intentionally distributed over the visible spectral range, we found that the absorption strength of all polymer samples are grouped in a random distribution within a rather uniform range of values.

Tear-Based Ocular Wearable Biosensors for Human Health Monitoring.

Wearable tear-based biosensors have garnered substantial interest for real time monitoring with an emphasis on personalized health care. These biosensors utilize major tear biomarkers such as proteins, lipids, metabolites, and electrolytes for the detection and recording of stable biological signals in a non-invasive manner. The present comprehensive review delves deep into the tear composition along with potential biomarkers that can identify, monitor, and predict certain ocular diseases such as dry eye disease, conjunctivitis, eye-related infections, as well as diabetes mellitus. Recent technologies in tear-based wearable point-of-care medical devices, specifically the state-of-the-art and prospects of glucose, pH, lactate, protein, lipid, and electrolyte sensing from tear are discussed. Finally, the review addresses the existing challenges associated with the widespread application of tear-based sensors, which will pave the way for advanced scientific research and development of such non-invasive health monitoring devices.

All-In-One Optoelectronic Transistors for Bio-Inspired Visual System.

Visual perception has profound effects on human decision-making and emotional responses. Replicating the functions of the human visual system through device development has been a constant pursuit in recent years. However, to fully simulate the various functions of the human visual system, it is often necessary to integrate multiple devices with different functions, resulting in complex, large-volume device structures and increased power consumption. Here, an optoelectronic transistor with comprehensive visual functions is introduced. By coupling diverse photoreceptive properties of the channel and electrical regulation through charge injection/ferroelectric switching from the hafnium-based gate, the devices can simulate functions of both photoreceptors in the retina and synapses in the visual cortex. A device array is constructed to confirm the perceptual functions of cone and rod cells. Subsequently, color discrimination and recognition for color images are achieved by combining the tunable perception and synapse functions. Then an intelligent traffic judgment system with this all-in-one device is developed, which is capable of making judgments and decisions regarding traffic signals and pedestrian movements. This work provides a potential solution for developing compact and efficient devices for the next-generation bio-inspired visual system.

Switching of ferrotoroidal domains via an intermediate mixed state in the multiferroic Y-type hexaferrite Ba0.5Sr1.5Mg2Fe12O22

We report a detailed study of the magnetic field switching of ferrotoroidal/multiferroic domains in the Y-type hexaferrite compound Ba0.5Sr1.5Mg2Fe12O22. By combining data from superconducting quantum interference device (SQUID) magnetometry, magnetocurrent measurements, and resonant x-ray scattering experiments, we arrive at a complete description of the deterministic switching, which involves the formation of a temperature-dependent mixed state in low magnetic fields. This mechanism is likely to be shared by other members of the hexaferrite family, and presents a challenge for the development of high-speed read-write memory devices based on these materials. Published by the American Physical Society 2024

Three‐Component Synthesis of Fluorescent 1,4‐Benzothiazin‐2‐ones Through Thiol‐Free Iodine‐Catalyzed Cyclization

AbstractA convergent synthesis of 2H‐benzo[b][1,4]thiazin‐2‐one was achieved via iodine‐catalyzed three‐component reaction. This strategy involves the formation of two new C−S bonds and a C−N bond from the readily available precursors ‐ aryl methyl ketones, p‐anisidine, and elemental sulfur to generate the desired heterocycle in moderate to good yields. As the synthesized benzothiazine‐2‐ones are fluorescent under UV light, photophysical properties like solid‐state emission, solvatochromism, Aggregation Induced Emission (AIE), and the relative quantum yields of the compounds were measured which proves them to be a potential candidate for the development of optoelectronic devices.

Unraveling the multistage phase transformations in monolayer MoTe2−x

Monolayer MoTe2 exhibits a variety of derivative structural phases and associated intriguing electronic properties that enable a wealth of potential applications in future electronic and optoelectronic devices. However, a comprehensive study focusing on the complexities of the controllable phase evolution in this atomically thin film has yet to be performed. This work aims to address this issue by systematically investigating molecular beam epitaxial growth of monolayer Mo–Te compounds on bilayer graphene substrates. By utilizing scanning tunneling microscopy, we explored a series of thermally driven structural phase evolutions, including distinct T′-MoTe2, H-MoTe2, Mo6Te6 nanowires, and multistoichiometric MoTe2−x. Furthermore, we carefully investigated the critical effects of the growth parameters—annealing temperature and time and tellurium concentration—on the controllable and reversible phase transformation within monolayer MoTe2−x. The findings have significant implications for understanding the thin film synthesis and phase transformation engineering inherent to two-dimensional crystals, which can foster further development of high-performance devices.

The technopolitics of border security R&D: Shaping the EU’s border in the Security Research Programme

Technologies are predominantly understood as ‘solutions’ for policy problems in EU border control. This has prompted increased political attention to research and development (R&D) of ‘innovative’ security technologies. The European Commission has continuously increased its spending on the development of security devices in the Security Research Programme; at the same time, border security institutions such as Frontex or eu-LISA have worked to amplify their influence on shaping security research in the EU’s Research Framework Programmes. Against this backdrop, this article develops the argument that R&D is a political practice of ‘making’ and governing the border through its entanglement with the politics of border security in the EU. By conceptualizing R&D as ‘borderwork’, the article interrogates how practices of security R&D inscribes specific logics into EU border security and control. In doing this, it also problematizes how R&D locks in exclusionary dichotomies and categorizations of mobilities through privileging security actors in the process. Based on qualitative interviews, the article provides an in-depth analysis of political processes through which R&D programmes and projects materialize at policymaking, implementing and operational levels. Through this, the article explores comprehensively how political logics of bordering are constantly shaping and simultaneously renegotiated in R&D.

Nondestructively Determining Soluble Solids Content of Blueberries Using Reflection Hyperspectral Imaging Technique

Effectively detecting the quality of blueberries is crucial for ensuring that high-quality products are supplied to the fresh market. This study developed a nondestructive method for determining the soluble solids content (SSC) of blueberry fruit by using a near-infrared hyperspectral imaging technique. The reflection hyperspectral images in the 900–1700 nm waveband range were collected from 480 fresh blueberry samples. An image analysis pipeline was developed to extract the spectrums of blueberries from the hyperspectral images. A regression model for quantifying SSC values was successfully established based on the full range of wavebands, achieving the highest RP2 of 0.8655 and the lowest RMSEP value of 0.4431 °Brix. Furthermore, three variable selection methods, namely the Successive Projections Algorithm (SPA), interval PLS (iPLS), and Genetic Algorithm (GA), were utilized to identify the feature wavebands for modeling. The models calibrated from feature wavebands generated an RMSEP of 0.4643 °Brix, 0.4791 °Brix, and 0.4764 °Brix, as well as the RP2 of 0.8507, 0.8397, and 0.8420 for SPA, iPLS, and GA, respectively. Furthermore, a pseudo-color distribution diagram of the SSC values within blueberries was successfully generated based on established models. This study demonstrated a novel approach for blueberry quality detection and inspection by jointly using hyperspectral imaging and machine learning methodologies. It can serve as a valuable reference for the development of grading equipment systems and portable testing devices for fruit quality assurance.

Poly(4‐methoxyaniline) composites: Investigating structure–property relationship towards semiconducting applications

ABSTRACTConjugated polymers are essential materials for the organic optoelectronic industry, serving a pivotal role in cutting‐edge technologies. In this study, we conducted an integrated characterization approach, including spectroscopic techniques coupled with X‐ray diffraction analysis to explore the structure–property relationship of poly(4‐methoxyaniline), commonly referred to as poly(p‐anisidine) or PPA, along with two distinct ceramic composites: PPA/α‐Al2O3 and PPA/Eu2O3. From powder X‐ray diffraction analysis, a triclinic unit cell in space group P1 is proposed, after the whole powder pattern decomposition (WPPD) refinement is employed for the semicrystalline regions of the polymeric phases. Fractal‐like structures are observed, following analysis of small‐angle X‐ray scattering (SAXS) data and scanning electron microscopy (SEM) from which we could infer the approximate sizes of the fractal clusters. Pure PPA displays a glass transition temperature (Tg) of approximately 80°C and an electrical conductivity slightly above 10−5 S/cm. In contrast, the composite materials do not exhibit a glass transition temperature but perform better in terms of crystallinity and thermal stability. PPA/Eu2O3 present conductivity enhancement exceeding tenfold, surpassing 10−4 S/cm. These findings provide the baseline for further explorations on the development of organic electronic devices and sensors.

Enhanced energy storage performance of tungsten bronze structured BaNb2O6-modified (Bi0.5Na0.5)TiO3 ceramics

The rapid development of the electronic devices and increasing attention to environmental problems have put forward a huge demand for high-performance lead-free dielectric energy storage ceramics. In this work, tungsten bronze structured BaNb2O6 (BN) modified perovskite structured (Bi0.5Na0.5)TiO3 (BNT) ceramics, BNT-xBN (0 <x< 0.15), were prepared to optimize the energy storage performance of BNT. The results show that the lattice distortion and dielectric relaxation behavior of BNT ceramic can be induced by BN addition. Meanwhile, the introduction of tungsten bronze structured BN results in the grain refinement and the increasing of resistivity, thereby significantly enhancing the electrical breakdown strength (Eb). Accordingly, the BNT-0.1BN ceramic displays good energy storage performance with high recoverable energy density (Wrec ∼ 3.41 J/cm3) at an great Eb of 358 kV/cm, accompanied by the wide temperature stability at 30–150 °C (Wrec varies within ±12.8 %, efficiency (η) varies within ±6.7 %). The enhanced energy storage performance demonstrates that introducing tungsten bronze structure is a feasible method to prepare high-performance perovskite energy storage ceramics.

Twist disclinations mediated transformations in confined nematic liquid crystals

We studied numerically structural transformations in different confined nematic liquid crystals (LC) mediated by chargeless (twist) disclinations. Firstly, we focus on the role of twist disclinations in Moiré-type geometrical setup where LC is confined in a plane-parallel cell. We impose an azimuthal rotation to initially parallel wedge disclinations where the total topological charge of the system equals to zero. Two qualitatively different scenarii are observed depending on the cell thickness. In thin enough cells the disclinations touch in the mid-plane which enables continuous transformation into a final structure consisting of two twist disclinations confined to the limiting substrates. On the other hand, in thinner cells an additional chargeless loop is formed in the mid-plane. In this case, on rotating the initially parallel disclinations periodic structural reentrant behavior is observed. In cylindrical geometry we considered transformations between the initial metastable escaped radial structure with point defects (ERPD) into escaped radial (ER) or planar polar structure with line defects (PPLD). In both cases two nearby ring-like point defects within the ERPD structure collide and temporarily form a chargeless twist disclination loop. The latter in the ERPD-ER transformation shrinks and enables continuous transformation into the final thermodynamically stable structure. On the contrary, in the ERPD-PPLD transformation the twist loop, whose local structure matches PPLD configuration, increases and converts the system continuously into the global PPLD configuration. Detailed understanding of chargeless defect mediated transformations is beneficial for development of future switching devices based on continuous nematic structural transformations between LC structures exhibiting significantly different optical features.

Lessons learned from the RE(ACT) conference on medical devices for rare diseases

The field of rare disease therapeutics has witnessed significant growth in recent years, highlighting the need for diverse therapeutic approaches to cater to the unique needs of individuals with rare diseases. Rare disease therapies encompass a broad spectrum of interventions, including orphan medicinal products, orphan medical devices, rehabilitative therapies, and digital therapeutics, with the lines between these categories blurring. This paper covers the session of the RE (ACT)-IRDiRC Conference 2023 and delves into the landscape of orphan medical device research and development, shedding light on the challenges and opportunities in this burgeoning field. It provides a short overview of the different international legislations in the field. In addition, it highlights several exemplary orphan medical devices. The first example is an exoskeleton for boys with Duchenne Muscular Dystrophy, enabling them to maintain arm functionality and independence. Another example presented was an EEG device linked to an app detecting seizures in rare epilepsy conditions, which alerts caregivers to seizures in real-time but also facilitates objective seizure reporting for clinicians, aiding in diagnosis and treatment optimization. It also showcases the role of gamification and enabling technologies in addressing rare diseases, by showing a game designed for children with cystic fibrosis, and a telemedicine system for rehabilitation therapy. Both solutions aim to improve patients' understanding of their conditions and enhance their self-management. In conclusion, this paper underscores the critical need for patient-centric orphan and pediatric medical devices to provide therapeutic options for individuals with rare diseases. It highlights the impact of existing devices on enhancing the quality of life for rare disease patients and emphasizes the necessity for greater incentives and support for research and development in this field.

Improvement of Self-Driven Nanowire-Based Ultraviolet Photodetectors by Metal-Organic Frameworks for Controlling Humanoid Robots.

Self-driven photodetectors (PDs) hold significant potential for the development of new information devices, which boast the advantages of ultralow power consumption and straightforward fabrication. In this study, we have proposed and demonstrated a self-driven ultraviolet PD utilizing gallium nitride/metal-organic framework (GaN/MOF) heterojunction nanowires successfully. By introducing Gd-ETTC MOFs on the surface of GaN nanowires, the photocurrent and responsivity of the device can be improved by approximately 75% under 310 nm illumination. Furthermore, they can also be effectively enhanced under visible light illumination. Owing to the appropriate energy level alignment, Gd-ETTC MOFs can serve as both a light harvester and a hole conductor, facilitating the efficient absorption, separation, and transmission of photogenerated carriers. It has been observed that due to reduced interface resistance, MOFs can enhance the charge transport through the acceleration of charge transfer. Furthermore, the PD equipped with MOFs is capable of continuous operation for 30,000 s, a feat attributable to the exceptional stability of both GaN nanowires and Gd-ETTC MOFs. By implementation of the humanoid robot systems, the control commands from the self-driven PD can drive the humanoid robot to execute different actions. The PD-equipped autonomous feedback system of a humanoid robot enables a seamless integration of light perception with intelligent robotic actions. Therefore, the design and demonstration of GaN/MOF nanowires hold significant reference value for further enhancing the performance of PDs and broadening their applications in ultralow-power artificial intelligence systems, humanoid intelligent robots, etc.

Band structures based phononic crystals in quasi-Sierpinski fractals with defects

This study presents a detailed analysis of the effects of geometric defects in phononic crystals, focusing on the use of a distribution of Sierpinski fractals for the strategic placement of inclusions. Using theoretical and computational approaches, we investigate the influence of these defects on the material's band structure. Phononic crystals, designed based on fractal geometry inspired by the Sierpinski pattern, are particularly sensitive to the introduction of inclusions, resulting in disorder in the periodic structure. Our study examines in detail how different defect configurations affect the formation of localized modes and the energy distribution in the material's band structure. The results obtained provide valuable insights into how the presence of geometric defects can be exploited or minimized in the design of phononic crystals for practical applications, including acoustic isolation, vibration control, and the development of advanced acoustic devices. These results contribute to the understanding and advancement of fractal phononic crystals, paving the way for future research and promising technological applications, both in terms of frequency and attenuation, depending on the complexity and hierarchy of the fractal structures used.

Design and development of an advanced gas storage device and control method for a novel compressed CO2 energy storage system

Compressed CO2 energy storage (CCES) has advantages over compressed air in energy density and efficiency. Compared to air, CO2 needs to be in a closed-loop cycle in the CCES. The development of CCES is constrained by low-pressure CO2 storage. Storage density can be increased by adsorption without changing pressure. However, the control of the flow rate during adsorption/desorption has rarely been studied experimentally. In this paper, an adsorption tower for CCES is proposed and the regulation of the desorption flow rate is experimentally investigated. Using temperature-swing adsorption, the storage and release can be regulated without reducing the energy storage capacity. During the desorption process, the temperature of the exhaust gas can also be maintained stably. The adsorbent with a volume of 51.81 L was able to release 6121.9 g of CO2 when heated to 200 °C. Under the same pressure conditions, the effective storage density of the tower can reach 118.2 g/L, which is 67.5 times higher than the gaseous density (1.75 g/L, 1 bar, 303 K). The desorption flow rate is linearly related to the forward speed of the front in the adsorption tower. The flow rate can be regulated by controlling the superficial gas velocity and the desorption temperature. This method can match the flow rate of the adsorption tower with the gas consumption of the compressor, providing a novel solution for CCES.

Detecting and Imaging of Magnons at Nanoscale with van der Waals Quantum Sensor

AbstractMagnonic devices are extensively studied for energy‐efficient information processing. High spatial resolution and high accuracy measurement is required to characterize the excitation and distribution of magnons. Here, sensing and imaging of magnons in the magnetic insulator (YIG) is realized with negatively charged boron vacancy () spin defects in 2D hexagonal boron nitride (hBN). Thermal magnon noise is studied through spin relaxometry, illustrating the nanometers proximity of the 2D quantum sensor over a large area. The small probe‐sample standoff distance helps to detect weak signals with diffraction‐limited spatial resolution. The uniform out‐of‐plane symmetry axis of is further utilized to study perpendicular magnetic anisotropy (PMA). It effectively extracts the stray field of microwave‐excited magnons from the direct stripline field. The distributions of propagating and localized magnons in different structures are subsequently imaged and analyzed. The work provides the strategy for utilizing the distinctive advantages of the van der Waals quantum sensor in magnetic imaging. The results will promote the development of magnonic devices for diverse applications.

Investigating the exciton dynamics in InGaN/GaN core-shell nanorods using time-resolved cathodoluminescence.

This study examines the exciton dynamics in InGaN/GaN core-shell nanorods using time-resolved cathodoluminescence (TRCL), which provides nanometer-scale lateral spatial and tens of picoseconds temporal resolutions. The focus is on thick (>20 nm) InGaN layers on the non-polar, semi-polar and polar InGaN facets, which are accessible for study due to the unique nanorod geometry. Spectrally integrated TRCL decay transients reveal distinct recombination behaviours across these facets, indicating varied exciton lifetimes. By extracting fast and slow lifetime components and observing their temperature trends along with those of the integrated and peak intensity, the differences in behaviour were linked to variations in point defect density and the degree and density of localisation centres in the different regions. Further analysis shows that the non-polar and polar regions demonstrate increasing lifetimes with decreasing emission energy, attributed to an increase in the depth of localisation. The semi-polar facet instead showed a spectral independence of the lifetime which could not be rationalised by an absence of exciton localisation. This investigation provides insights into the intricate exciton dynamics in InGaN/GaN nanorods, offering valuable information for the design and development of optoelectronic devices.

Optoplasmonic tuneable response by femtosecond laser irradiation of glass with deep-implanted gold nanoparticles

The manipulation of the optical properties of plasmonic nanocomposites is of high interest for the development of advanced optical devices with tailored unique properties. Achieving these objectives requires a combination of synthesis techniques and post-fabrication strategies. Here, we combine the use of two well-established physical strategies: MeV ion implantation and femtosecond laser processing. Firstly, we synthesize Au-doped soda lime glass nanocomposite through ion beam implantation (Au2+ at 1.8 MeV) followed by thermal annealing. This synthesis procedure results in a peculiar optical response based on the combination of Au-nanoparticle plasmonic resonance and a Fabry-Perot interference, caused by the deep implantation (centered at 480 nm). Secondly, this dual response is demonstrated to be highly tuneable by non-resonant femtosecond laser irradiation (800-nm wavelength and 130-fs pulse duration). Depending on the laser fluence, three transformation regimes are distinguished: supressing the interferometric response by spallative ablation, inducing vivid blue colors by surface swelling, and producing red-shifted color changes by multi-shot irradiation at low fluences. The proposed method is very versatile, since it is applicable to any dielectric matrix or implanted element. This work paves the way to a new route for the development of scalable and tuneable nanocomposites with several potential applications in optics.

Significant enhancement of bi-directional ultrahigh thermal conductivity in polymer composites fabricated via Polyetherimide@Silver core–shell structured microspheres

Nowadays, the polymer-based composites with excellent thermal-conductive ability and ideal electromagnetic interference shielding performance are in great demand with the advent of developing modern electronic technology. However, most conventional thermal-conductive materials were typically designed to enhance thermal conductivity in just one single direction (through-plane or in-plane direction), which will be inadequate to meet increasing heat-dissipation requirements. Hence, polyetherimide/Silver (PEI/Ag) composites with unique segregated thermal-conductive network were fabricated via hot-pressing the core–shell (PEI@Ag) particles, which was endowed with superior thermal-conductive ability in bi-directions. By this process, the Ag shell was deposited on the surface of various polymer microsphere, and diverse morphology of composite particles would lead to different findings. The results show the PEI@Ag composites with filler content of 18.9 vol% exhibited high in-plane thermal conductivity and through-plane thermal conductivity of 19.9 and 14.0 W/mK, respectively. Particularly, these results achieved obvious improvements of 331 % and 1264 % higher than the composites with filler random distribution, indicating the composite materials obtained outstanding advantage in both horizontal and vertical direction. The research also found that the composites prepared from PEI@Ag core–shell structures possess better properties than those prepared with Ag nanoparticles growing on polymers, indicating the importance of continuous heat-transfer path, and their heat transfer behavior was further demonstrated by finite element analysis. Besides, the composites also exhibited remarkable EMI shielding performance (40.1 dB)). In a word, this study provides viable strategies to enhance the thermal conductivity of composites based on organic solvent-soluble polymer with EMI capability for the development of electronic devices.