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Aim: To evaluate the potential association between suicidality and glucagon‐like peptide‐1 receptor agonists (GLP‐1RAs), as well as other medications used for obesity and diabetes, using comprehensive global data. Materials and Methods: This study utilized the World Health Organization's pharmacovigilance database, encompassing adverse drug reaction reports from 1967 to 2023, from 170 countries (total reports, N = 131 255 418). We present the reported odds ratios (RORs) with 95% confidence intervals (CIs) and information component (IC) with IC025 regarding the association between GLP‐1RA use and suicidality. Results: Although reports of GLP‐1RA‐associated suicidality increased gradually from 2005 to 2023 (n = 332), no evidence of an association was observed (ROR 0.15 [95% CI 0.13 to 0.16]; IC −2.77 [IC025 −2.95]). The lack of evidence of an association persisted regardless of whether GLP‐1RAs were used for diabetes treatment (ROR 0.13 [95% CI 0.11 to 0.14]; IC −2.95 [IC025 −3.14]) or obesity treatment (ROR 0.44 [95% CI 0.34 to 0.58]; IC −1.16 [IC025 −1.62]). However, an association was found between suicidality and other diabetes medications excluding GLP‐1RAs (ROR 1.13 [95% CI 1.10 to 1.15]; IC 0.17 [IC025 0.13]). Similarly, the potential association with suicidality was observed in medications used to treat obesity excluding GLP‐1RAs (ROR 1.08 [95% CI 1.01 to 1.14]; IC 0.10 [IC025 0.01]). Conclusions: The suspected association between GLP‐1RA use and suicidality, as raised by the European Medicines Agency, was not found in our global analysis. This indicates that the sporadic reports of GLP‐1RA‐associated suicidality are likely influenced by factors such as comorbidities present in the GLP‐1RA user population. [ABSTRACT FROM AUTHOR]

Three-dimensional(3D) shape measurement using point clouds has recently gained significant attention. Phase measuring profilometry (PMP) is widely preferred for its robustness against external lighting changes and high-precision results. However, PMP suffers from long computation times due to complex calculations and its high memory usage. It also faces a 2π ambiguity issue, as the measured phase is limited to the 2π range. This is typically resolved using dual-wavelength methods. However, these methods require separate measurements of phase changes at two wavelengths, increasing the data processing volume and computation times. Our study addresses these challenges by implementing a 3D shape measurement system on a System-on-Chip (SoC)-type Field-Programmable Gate Array (FPGA). We developed a PMP algorithm with dual-wavelength methods, accelerating it through high-level synthesis (HLS) on the FPGA. This hardware implementation significantly reduces computation time while maintaining measurement accuracy. The experimental results demonstrate that our system operates correctly on the SoC-type FPGA, achieving computation speeds approximately 11.55 times higher than those of conventional software implementations. Our approach offers a practical solution for real-time 3D shape measurement, potentially benefiting applications in fields such as quality control, robotics, and computer vision. [ABSTRACT FROM AUTHOR]

Objectives: This consensus was developed by the Asian EUS Group (AEG), who aimed to formulate a set of practice guidelines addressing various aspects of endoscopic ultrasound‐guided tissue acquisition (EUS‐TA). Methods: The AEG initiated the development of consensus statements and formed an expert panel comprising surgeons, gastroenterologists, and pathologists. Three online consensus meetings were conducted to consolidate the statements and votes. The statements were presented and discussed in the first two consensus meetings and revised according to comments. Final voting was conducted at a third consensus meeting. The Grading of Recommendations, Assessment, Development, and Evaluation system was adopted to define the strength of the recommendations and quality of evidence. Results: A total of 20 clinical questions and statements regarding EUS‐TA were formulated. The committee recommended that fine‐needle biopsy (FNB) needles be preferred over conventional fine‐needle aspiration (FNA) needles for EUS‐TA of subepithelial lesions. For solid pancreatic masses, rapid on‐site evaluation is not routinely recommended when FNB needles are used. For dedicated FNB needles, fork‐tip and Franseen‐tip needles have essentially equivalent performance. Conclusion: This consensus provides guidance for EUS‐TA, thereby enhancing the quality of EUS‐TA. [ABSTRACT FROM AUTHOR]

Ensemble species distribution modeling offers a robust approach to reduce the inherent uncertainties associated with single models, and ultimately providing more accurate predictions of regions with a heightened probability of occurrence. As Corythucha ciliata (Say) damages deciduous trees in diverse environments, including urban, suburban and forested regions, the objective of this study was to predict the potential distribution of C. ciliata by developing an ensemble model that comprehensively considered the biological and habitat traits of the pest using the CLIMEX and MaxEnt models. Although the ensemble model did not have significantly improved performance, compared with the single MaxEnt model, it was robust compared with distribution data. Our predictions suggest that C. ciliata will gradually expand its range from its current distribution in response to climate change, necessitating focused monitoring and pest‐control efforts in the predicted regions. This study not only evaluates pest distribution but also provides crucial insights into effective control strategies, which are adaptable to other pest management scenarios. [ABSTRACT FROM AUTHOR]

We report the first North American origin class I avian orthoavulavirus 1 (AOAV-1) isolated from a faecal dropping of wild Eurasian teal (Anas crecca) in South Korea. Whole genome sequencing and comparative phylogenetic analysis revealed that the AOAV-1/Eurasian teal/South Korea/KU1405-3/2017 virus belongs to the sub-genotype 1.2 of class I AOAV-1. Phylogenetic analysis suggested multiple introductions of the North American sub-genotype 1.2 viruses into Asia and its establishment in the wild bird population in East Asia since May 2011. These results provide information on the epidemiology of AOAV-1, particularly the role of migratory wild birds in exchanging viruses between the Eurasian and North American continents. Enhanced genomic surveillance is required to improve our understanding on the evolution and transmission dynamics of AOAV-1 in wild birds. [ABSTRACT FROM AUTHOR]

There is a need to design a hardware synapse array appropriate for enhancing the efficiency of neuromorphic computing systems while minimizing energy consumption. This study introduces a memristor device with an AlOx overshoot suppression layer (A‐OSL) to achieve a self‐compliance effect. By optimizing each cell within the 16 × 16 crossbar array, synaptic devices are successfully fabricated with reliable characteristics and 3‐bit multilevel capabilities. In addition, the oxygen composition of TiOx and the annealing conditions are optimized to reduce the forming voltage and minimize the variation in the switching voltage. As a result, stable forming‐free characteristics are obtained through A‐OSL insertion, a reduction in forming voltage, and TiOx oxygen composition optimization. Also, target weights are accurately transferred to the A‐OSL memristor crossbar array and conducted the inference process by applying spike signals to the array following the designated time step. The spiking neural network (SNN) is demonstrated by measuring vector‐matrix multiplication (VMM) of the 16 × 16 crossbar array. The VMM results exhibit a classification accuracy of 90.80% for the MNIST dataset, which is close to the accuracy achieved by software‐based approaches, amounting to 91.85%. [ABSTRACT FROM AUTHOR]

Background: Comprehensive quantitative evidence on the risk and protective factors for sudden infant death syndrome (SIDS) effects is lacking. We investigated the risk and protective factors related to SIDS. Methods: We conducted an umbrella review of meta-analyses of observational and interventional studies assessing SIDS-related factors. PubMed/MEDLINE, Embase, EBSCO, and Google Scholar were searched from inception until January 18, 2023. Data extraction, quality assessment, and certainty of evidence were assessed by using A Measurement Tool Assessment Systematic Reviews 2 following PRISMA guidelines. According to observational evidence, credibility was graded and classified by class and quality of evidence (CE; convincing, highly suggestive, suggestive, weak, or not significant). Our study protocol was registered with PROSPERO (CRD42023458696). The risk and protective factors related to SIDS are presented as equivalent odds ratios (eORs). Results: We identified eight original meta-analyses, including 152 original articles, covering 12 unique risk and protective factors for SIDS across 21 countries/regions and five continents. Several risk factors, including prenatal drug exposure [eOR = 7.84 (95% CI = 4.81–12.79), CE = highly suggestive], prenatal opioid exposure [9.55 (95% CI = 4.87–18.72), CE = suggestive], prenatal methadone exposure [9.52 (95% CI = 3.34–27.10), CE = weak], prenatal cocaine exposure [4.38 (95% CI = 1.95–9.86), CE = weak], prenatal maternal smoking [2.25 (95% CI = 1.95–2.60), CE = highly suggestive], postnatal maternal smoking [1.97 (95% CI = 1.75–2.22), CE = weak], bed sharing [2.89 (95% CI = 1.81–4.60), CE = weak], and infants found with heads covered by bedclothes after last sleep [11.01 (95% CI = 5.40–22.45), CE = suggestive], were identified. On the other hand, three protective factors, namely, breastfeeding [0.57 (95% CI = 0.39–0.83), CE = non-significant], supine sleeping position [0.48 (95% CI = 0.37–0.63), CE = suggestive], and pacifier use [0.44 (95% CI = 0.30–0.65), CE = weak], were also identified. Conclusions: Based on the evidence, we propose several risk and protective factors for SIDS. This study suggests the need for further studies on SIDS-related factors supported by weak credibility, no association, or a lack of adequate research. [ABSTRACT FROM AUTHOR]

Epitaxial regrowth of GaN pn junctions is a key technology for realization of a variety of high-performance GaN power electronic devices. However, the regrowth process can introduce impurities and defects that degrade a device's performance. Here, we show that scanning Kelvin probe force microscopy and scanning capacitance microscopy can be used in a cross-sectional geometry to probe dopant distributions and an electronic structure in epitaxially grown GaN pn junctions. These measurements enable profiling of potential and dopant distributions across GaN pn junctions produced by uninterrupted epitaxial growth and by regrowth on an etched surface. Clear differences are observed in comparisons to the electronic structure of these two types of junctions that can be correlated with results of complementary characterization of dopant distributions reported for similarly grown structures. These measurements also suggest the presence of defects in etch-and-regrow pn junction structures that extend nearly 1 μm below the regrown interface. [ABSTRACT FROM AUTHOR]

This study implements a highly uniform 3D vertically stack resistive random‐access memory (VRRAM) with a four‐layer contact hole structure. The fabrication process of a four‐layer VRRAM is demonstrated, and its physical and electrical properties are thoroughly examined. X‐ray photoelectron spectroscopy and transmission electron microscopy are employed to analyze the chemical distribution and physical structure of the VRRAM device. Multilevel capability, reliable endurance (>104 cycles), and retention (104 s) are successfully obtained. Synaptic memory plasticity, such as spike time‐dependent plasticity, spike rate‐dependent plasticity, excitatory post‐synaptic current, paired‐pulse facilitation, and long‐term potentiation and depression is presented. Finally, the vector‐matrix multiplication (VMM) operation is conducted on a 4 × 12 VRRAM array, according to the low resistance state ratio. It is ascertained that the accuracy drop, which can occur due to VMM error, can be limited to a decrease of less than 0.44% point. Utilizing the high‐density, multilevel, and biological characteristics of VRRAM, it is possible to implement high‐performance neuromorphic systems that require densely integrated synaptic devices. [ABSTRACT FROM AUTHOR]

Background: Reactive oxygen species (ROS) have been shown to promote tumour growth and metastasis in human cell lines. The superoxide anion (•O2−) is produced during ROS formation and is involved in tumour cell signalling. Objectives: Superoxide dismutase (SOD) has been applied to canine mammary gland tumours to investigate its antitumour effects in vitro. Methods: Cell proliferation, cell cycle cell migration assays, reverse transcription‐quantitative polymerase chain reaction, and western blot analysis were performed to determine the effects of SOD on canine mammary tumour cell line. Results: SOD treatment resulted in anti‐proliferative effects and mediated cell cycle arrest in the canine mammary gland tumour cell lines (CIPp and CIPm). It also downregulated the expression of N‐cadherin and Vimentin. Conclusions: The results confirmed that SOD inhibits tumour cell proliferation and migration, thus supporting the potential applications of SOD as a chemotherapeutic agent for canine mammary gland tumours. [ABSTRACT FROM AUTHOR]

Individually functionalized cation‐ and anion‐based ionic additives are designed to mitigate the interfacial side reaction occurring on both the positive and negative electrode surfaces. By applying 1‐phenyl‐1H‐imidazole‐3‐ium trifluoromethanesulfonate as a surface‐targeting electrolyte additive, the reciprocal failure from multiple electrolyte addition applications is theoretically prevented. Selective interface modification is performed using ionic additives by the migration of cations and anions to the negative and positive electrode surfaces, respectively. A drastic improvement in cycleability compared with that by a general carbonate electrolyte is achieved because the reinforcement of both the graphite and LiNi0.8Co0.1Mn0.1O2 electrode surface is possible by ionic additives. Moreover, a further improvement in the cycle performance compared with that by the typical solid electrolyte interphase‐forming additives, such as vinylene carbonate and fluoroethylene carbonate, is demonstrated by the ionic additive. [ABSTRACT FROM AUTHOR]

To efficiently develop an extremely intensive storage memory, the resistive random‐access memory (RRAM), which operates by producing and rupturing conductive filaments, is essential. However, due to the stochastic nature of filament production, this filamentary type resistive switching has an inherent limitation, which entails the unpredictability of the driving voltage and resistance states. Several strategies such as doping, research into multilayer stacks, and interface engineering, are suggested to tackle this challenge. This work fabricates a CMOS‐compatible TiN/HfOx/TiN‐NCs (nanocrystals)/HfOx/TiN RRAM to implement analog resistive switching and advance the development of the synaptic device. Specifically, atomic force microscopy (AFM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) are utilized to observe the formation of TiN nanocrystals, which play a crucial role in the enhancement of resistive switching. By comparing HfOx–based RRAM devices with and without NCs, the DC I–V curves, retention, endurance, and switching speed are properly examined. Interestingly, it is found that the TiN/HfOx/TiN‐NCs/HfOx/TiN device is more appropriately utilized as an artificial synapse in neuromorphic systems mainly due to its stable and reliable resistive switching properties. Finally, this work demonstrates well‐controlled resistive switching 3D vertical RRAM with TiN‐NCs, which is particularly suitable for high‐density memory. [ABSTRACT FROM AUTHOR]

Single‐crystalline inorganic semiconductor nanomembranes (NMs) have attracted great attention over the last decade, which poses great advantages to complex device integration. Applications in heterogeneous electronics and flexible electronics have been demonstrated with various semiconductor nanomembranes. Single‐crystalline aluminum nitride (AlN), as an ultrawide‐bandgap semiconductor with great potential in applications such as high‐power electronics has not been demonstrated in its NM forms. This very first report demonstrates the creation, transfer‐printing, and characteristics of the high‐quality single‐crystalline AlN NMs. This work successfully transfers the AlN NMs onto various foreign substrates. The crystalline quality of the NMs has been characterized by a broad range of techniques before and after the transfer‐printing and no degradation in crystal quality has been observed. Interestingly, a partial relaxation of the tensile stress has been observed when comparing the original as‐grown AlN epi and the transferred AlN NMs. In addition, the transferred AlN NMs exhibits the presence of piezoelectricity at the nanoscale, as confirmed by piezoelectric force microscopy. This work also comments on the advantages and the challenges of the approach. Potentially, the novel approach opens a viable path for the development of the AlN‐based heterogeneous integration and future novel electronics and optoelectronics. [ABSTRACT FROM AUTHOR]

Memristor devices can be utilized for various computing applications, and stochastic computing is one of them. The intrinsic stochastic characteristics of the memristor cause unpredictable current fluctuations by the capture and emission of electrons in a trap site. Herein, a true random number generator (TRNG) using the random telegraph noise (RTN) of the memristor as an entropy source is proposed. TiOx/Al2O3 memristors are fabricated, and the capture time probability of the RTN characteristics is modulated to 50% with varying read‐voltage and device conductance state. In addition, the TRNG operations with the RTN current signals as entropy sources are experimentally demonstrated with a customized breadboard, and the randomness is verified with the National Institute of Standards and Technology (NIST) tests. [ABSTRACT FROM AUTHOR]

Obesity produces many health problems, including systemic oxidative stress. This study comprehensively investigated the effects of Sanguisorba officinalis L. extract (SO) as an antioxidant on abnormal lipid accumulation and oxidative stress in 3T3-L1 adipocytes and high-fat diet (HFD)-induced obese mice (n = 48). We evaluated the anti-adipogenic and antioxidant effects of SO on 3T3-L1 by cell viability, Oil red O staining, and NBT assays. The ameliorative effects of SO in HFD-induced C57BL/6J mice were investigated by measuring body weight, serum lipids, adipocyte size, hepatic steatosis, AMPK pathway-related proteins, and thermogenic factors. In addition, the effect of SO on oxidative stress in obese mice was evaluated by the activity of antioxidant enzymes and the production of lipid peroxidation products and ROS production in adipose tissue. We found that SO dose-dependently decreased lipid accumulation and ROS production in 3T3-L1 adipocytes. In C57BL/6J obese mice, SO (above 200 mg/kg) attenuated the HFD-induced gain in body weight and white adipose tissue (WAT) weight without affecting appetite. SO also decreased serum glucose, lipid, and leptin levels and attenuated adipocyte hypertrophy and hepatic steatosis. Furthermore, SO increased the expression of SOD1 and SOD2 in WAT, decreased ROS and lipid peroxides, and activated the AMPK pathway and thermogenic factors. In summary, SO reduces oxidative stress in adipose tissue by increasing antioxidant enzyme activity and improves obesity symptoms through AMPK-pathway-regulated energy metabolism and mitochondrial respiratory thermogenesis. [ABSTRACT FROM AUTHOR]

Background and Aim: Dedicated studies evaluating the impact of COVID‐19 on outcomes of pancreatobiliary IgG4 related disease (IgG4‐RD) patients are scarce. Whether COVID‐19 infection or vaccination would trigger IgG4‐RD exacerbation remains unknown. Methods: Pancreatobiliary IgG4‐RD patients ≥ 18 years old with active follow‐up since January 2020 from nine referral centers in Asia, Europe, and North America were included in this multicenter retrospective study. Outcome measures include incidence and severity of COVID‐19 infection, IgG4‐RD disease activity and treatment status, interruption of indicated IgG4‐RD treatment. Prospective data on COVID‐19 vaccination status and new COVID‐19 infection during the Omicron outbreak were also retrieved in the Hong Kong cohort. Results: Of the 124 pancreatobiliary IgG4‐RD patients, 25.0% had active IgG4‐RD, 71.0% were on immunosuppressive therapies and 80.6% had ≥ 1 risk factor for severe COVID. In 2020 (pre‐vaccination period), two patients (1.6%) had COVID‐19 infection (one requiring ICU admission), and 7.2% of patients had interruptions in indicated immunosuppressive treatment for IgG4‐RD. Despite a high vaccination rate (85.0%), COVID‐19 infection rate has increased to 20.0% during Omicron outbreak in the Hong Kong cohort. A trend towards higher COVID‐19 infection rate was noted in the non‐fully vaccinated/unvaccinated group (17.6% vs 33.3%, P = 0.376). No IgG4‐RD exacerbation following COVID‐19 vaccination or infection was observed. Conclusion: While a low COVID‐19 infection rate with no mortality was observed in pancreatobiliary IgG4‐RD patients in the pre‐vaccination period of COVID‐19, infection rate has increased during the Omicron outbreak despite a high vaccination rate. No IgG4‐RD exacerbation after COVID‐19 infection or vaccination was observed. [ABSTRACT FROM AUTHOR]

Memristor‐based ternary content‐addressable memory (TCAM) has emerged as an alternative to conventional static random‐access memory (SRAM)‐based TCAM because of its high‐density integration and zero‐static energy consumption. Herein, 0T2R TCAM operation on a 32 × 32 passive memristor crossbar circuit is experimentally verified. The effective margin, which is the difference between the match case and 1‐bit mismatch case, is improved through precise tuning operations. Moreover, the number of mismatch bits and match cases can be accurately detected thanks to the linear relationship between the number of mismatch bits and match‐line current. In addition, the nonideal effects in the passive crossbar array including dynamic voltage drop and sneak current are analyzed through SPICE studies. These results indicate that the proposed TCAM operating conditions can ensure stable TCAM operation in larger arrays. [ABSTRACT FROM AUTHOR]

Metabolism, is a complex process involving the gut and the liver tissue, is difficult to be reproduced in vitro with conventional single cell culture systems. To tackle this challenge, we developed a gut-liver-axis chip consisting of the gut epithelial cell chamber and three-dimensional (3D) uniform-sized liver spheroid chamber. Two cell culture chamber compartments were separated with a porous membrane to prevent microorganisms from passing through the chamber. When the hepG2 spheroids cultured with microbiota-derived metabolites, we observed the changes in the physiological function of hepG2 spheroids, showing that the albumin and urea secretion activity of liver spheroids was significantly enhanced. Additionally, the functional validation of hepG2 spheroids treated with microbiota-derived exosome was evaluated that the treatment of the microbiota-derived exosome significantly enhanced albumin and urea in hepG2 spheroids in a gut-liver axis chip. Therefore, this gut-liver axis chip could be a potentially powerful co-culture platform to study the interaction of microbiota and host cells. [ABSTRACT FROM AUTHOR]

A three-dimensional (3D) tumor spheroid model plays a critical role in mimicking tumor microenvironments in vivo. However, the conventional culture methods lack the ability to manipulate the 3D tumor spheroids in a homogeneous manner. To address this limitation, we developed a microfluidic-based droplet system for drug screening applications. We used a tree-shaped gradient generator to control the cell density and encapsulate the cells within uniform-sized droplets to generate a 3D gradient-sized tumor spheroid. Using this microfluidic-based droplet system, we demonstrated the high-throughput generation of uniform 3D tumor spheroids containing various cellular ratios for the analysis of the anti-cancer drug cytotoxicity. Consequently, this microfluidic-based gradient droplet generator could be a potentially powerful tool for anti-cancer drug screening applications. [ABSTRACT FROM AUTHOR]

To apply resistive random‐access memory (RRAM) to the neuromorphic system and improve performance, each cell in the array should be able to operate independently by reducing device variation. In addition, it is necessary to lower the operating current of the RRAM cell and enable gradual switching characteristics to mimic the low‐energy operations of biological. In most filamentary RRAMs, however, overshoot current occurs in the forming stage, and the RRAM shows large device variation, high operating current, and abrupt set and reset switching characteristics. Herein, the shortcomings occurring in the forming stage are overcome by introducing and optimizing an overshoot suppression layer. Consequently, the RRAM exhibits gradual switching characteristics both in the set and reset regions, thereby enabling implementation of 4‐bit multilevel operation. In addition, the forming step can be easily performed in a 16 × 16 crossbar array owing to its self‐compliance characteristics without disturbing neighboring cells in the array. The tuning and vector–matrix multiplication (VMM) operations are also experimentally verified in the array. Finally, classification performance with off‐chip training is compared in terms of accuracy and robustness to tuning tolerance depending on the number of bits of the implemented multiconductance levels. [ABSTRACT FROM AUTHOR]

To analyze the effect of the intrinsic variations of the memristor device on the neuromorphic system, we fabricated 32 × 32 Al2O3/TiO x -based memristor crossbar array and implemented 3 bit multilevel conductance as weight quantization by utilizing the switching characteristics to minimize the performance degradation of the neural network. The tuning operation for 8 weight levels was confirmed with a tolerance of ±4 μ A (±40 μ S). The endurance and retention characteristics were also verified, and the random telegraph noise (RTN) characteristics were measured according to the weight range to evaluate the internal stochastic variation effect. Subsequently, a memristive neural network was constructed by off-chip training with differential memristor pairs for the Modified National Institute of Standards and Technology (MNIST) handwritten dataset. The pre-trained weights were quantized, and the classification accuracy was evaluated by applying the intrinsic variations to each quantized weight. The intrinsic variations were applied using the measured weight inaccuracy given by the tuning tolerance, RTN characteristics, and the fault device yield. We believe these results should be considered when the pre-trained weights are transferred to a memristive neural network by off-chip training. [ABSTRACT FROM AUTHOR]

Recently, various memory devices have been actively studied as suitable candidates for synaptic devices, which are important memory and computing units in neuromorphic systems. One of the ways to manage these devices is off-chip training, where it is essential to transfer the pretrained weights accurately. Previous studies, however, have a few limitations, such as a lack of consideration of program errors that occur during the transfer process. Although the smaller the program error, the higher the accuracy, the corresponding increase in the program time must be considered. To evaluate the practical applicability, we fabricated Al2O3/TiOx-based resistive random access memory (RRAM) and investigated the effect of program errors on program time and system degradation. It was confirmed that for smaller program errors, the program time was exponentially longer. Furthermore, we examined the effect of variation with respect to the number of quantized weight states (${N}_{state}$) through system-level simulation. We observed that the optimized ${N}_{state}$ varies depending on whether the program error is small or large. This result is meaningful as it experimentally shows the tradeoff between the program error, program time, and system performance. We expect it to be useful in the development of neuromorphic systems. [ABSTRACT FROM AUTHOR]

We report the first detection of Y280‐lineage H9N2 avian influenza viruses in live bird markets in Korea during July 2020. The viruses were isolated from domestic ducks and chickens traded in three markets in two different provinces, indicating dispersal of the newly introduced viruses. Complete genome sequencing and comparative phylogenetic analyses of all eight gene segments of the viruses showed high nucleotide homology to a Y280‐lineage H9N2 avian influenza virus isolated in a chicken farm in China, which belongs to one of the most prevalent H9N2 genotypes in China. Increasing human cases of the same genotype H9N2 infection in China and the mammalian specific markers present in the viruses isolated suggest potential implications for public health. [ABSTRACT FROM AUTHOR]

A ZnFe2O4/poly(diphenylamine) (PDPA) particle with a core–shell structure was successfully synthesized with a ZnFe2O4 core via the solvothermal method, modifying ZnFe2O4 through a grafting agent and coating with a PDPA shell through the radical polymerization method. ZnFe2O4 is introduced as a new magnetorheological (MR) material because of its low density and sufficient saturation magnetization ($M_{s}$) value. PDPA does not require an additional de-doping process during electrorheological (ER) measurements because it has a lower electrical conductivity than typical conducting polymer of polyaniline. By measuring the morphology of the synthesized particles through transmission electron microscopy, it was confirmed that the core–shell structure was successfully synthesized and that the shell thickness of PDPA was approximately 14 nm. The density of the synthesized particles is 2.7 g/cm3, which is sufficiently lower than the density of ZnFe2O4 (4.67 g/cm3), showing good sedimentation stability. The results from measuring the magnetic properties using a vibrating sample magnetometer indicate that the saturation magnetization value of ZnFe2O4/PDPA was approximately 40.8 emu/g. ZnFe2O4/PDPA particles were dispersed in 100 cs silicone oil by 5 vol.% to prepare a ZnFe2O4/PDPA-based electro/magnetorheological (EMR) fluid, and the shear response and dynamic response were measured using a rotational rheometer to measure the MR/ER properties. [ABSTRACT FROM AUTHOR]

As the computing paradigm has shifted toward edge computing, improving the security of edge devices is attracting significant attention. However, because edge devices have limited resources in terms of power and area, it is difficult to apply a conventional cryptography system to protect them. On the other hand, as a simple security application, a physical unclonable function (PUF) can be implemented without power and area problems because it provides a security key by utilizing process variations without additional external circuits. Ferroelectric tunnel junctions (FTJs) are 2-terminal devices that store information by changing the resistance of a ferroelectric material, where the resistance is determined by the polarization states of the ferroelectric domains. Because polycrystalline ferroelectric materials have a multi-domain nature, domain variation can also be used as a randomness source to induce cell-to-cell variations along with process variations. In this paper, we demonstrate PUF operations of a low-power, small area 16 × 16 hafnium oxide (pure-HfOx)-based FTJ array using certain metrics. It is clear that the proposed array consisting of scaled FTJs has adequate randomness for security applications such that the array-level PUF operations are robust against model-based machine learning attacks. [ABSTRACT FROM AUTHOR]

The semiconductor manufacturing processes have been evolved to improve the yield rate. Here, we studied a sequential and comprehensive algorithm that could be used for fault detection and classification (FDC) of the semiconductor chips. A statistical process control (SPC) method is employed for inspecting whether sensors used in the semiconductor manufacturing process become stable or not. When the sensors are individually stable, the algorithm conducts the relational inspection to identify the relationship between two sensors. The key factor here is the coefficient of determination (R2). If R2 is calculated as more than 0.7, their relationship is analyzed through the regression analysis, while the algorithm conducts the clustering analysis to the sensor pair with R2 less than 0.7. This analysis also provided the capability to determine whether the newly generated data are defective or defect-free. Therefore, this study is not only applied to the semiconductor manufacturing process but can also be to the various research fields where the big data are treated. [ABSTRACT FROM AUTHOR]

In recent days, more hardware-driven artificial intelligence system capable of brain-like low-energy consumption is gaining ever-increasing interest. The hardware-driven property lies in the low-power synaptic device and its array along with the area and energy-efficient neuron circuits. In this work, a spiking neural network (SNN) based on analog synaptic device of resistive-switching random access memory (RRAM) is constructed from the experimentally fabricated devices. Furthermore, the capability of the designed SNN hardware for sequential tasks through an optimal reinforcement learning (RL) algorithm is demonstrated. More specifically, the Rush Hour game is conducted as an example of applications for the sequential task for which an SNN architecture is plausibly suited. The rule of the game is simple but has not been demonstrated by a hardware-oriented artificial neural network (ANN) yet, and in this work, it is reported that the analog RRAM synaptic devices in the cross-point array architecture successfully solve the problem via the RL algorithm. [ABSTRACT FROM AUTHOR]

Monodisperse semiconducting poly(N-methylaniline) (PNMA) microspheres with a suitable electrical conductivity were fabricated using a chemical oxidation process and employed in an electrorheological (ER) suspension. Morphological image of the synthesized PNMA microsphere was assessed via scanning electron microscope and transmission electron microscope. Its chemical composition and thermal behavior were determined using Fourier-transform infrared and thermal gravimetric analysis, respectively. Chain-like structure formation under an input electric field in ER fluid containing silicone oil and 10 wt% PNMA microspheres was observed directly with optical microscopy. Viscoelastic characteristics of the ER fluid under an input electric field were evaluated with a rotational rheometer. Yield stress with a power exponent of 1.5 was observed, along with typical solid-like property under electric field. Dielectric behavior of the ER suspension measured was also found to be closely associated with its ER behavior. [ABSTRACT FROM AUTHOR]

As interest in artificial intelligence (AI) and relevant hardware technologies has been developed rapidly, algorithms and network structures have become significantly complicated, causing serious power consumption issues because an enormous amount of computation is required. Neuromorphic computing, a hardware AI technology with memory devices, has emerged to solve this problem. For this application, multilevel operations of synaptic devices are important to imitate floating point weight values in software AI technologies. Furthermore, weight transfer methods to desired weight targets must be arranged for off-chip training. From this point of view, we fabricate 32 × 32 memristor crossbar array and verify the 3-bit multilevel operations. The programming accuracy is verified for 3-bit quantized levels by applying a reset-voltage-control programming scheme to the fabricated TiOx/Al2O3-based memristor array. After that, a synapse composed of two differential memristors and a fully-connected neural network for modified national institute of standards and technology (MNIST) pattern recognition are constructed. The trained weights are post-training quantized in consideration of the 3-bit characteristics of the memristor. Finally, the effect of programming error on classification accuracy is verified based on the measured data, and we obtained 98.12% classification accuracy for MNIST data with the programming accuracy of 1.79% root-mean-square-error. These results imply that the proposed reset-voltage-control programming scheme can be utilized for a precise tuning, and expected to contribute for the development of a neuromorphic system capable of highly precise weight transfer. [ABSTRACT FROM AUTHOR]

Experiments are conducted to compare the resistive switching characteristics for several samples with different amounts of Ag deposition in TiN/Ag/SiNx/TiN conductive bridging random access memory (CBRAM). The compliance current in TiN/Ag/SiNx/TiN CBRAM determines the volatile/non-volatile memory operation as the current level controls the strength of the filament made of Ag. The transient measurement showed that the effective thickness of Ag source layer in the TiN/Ag/SiNx/TiN controls the supply of the Ag atoms into the insulating layer, affecting the strength of the conductive bridge. The mechanism for the switching characteristics and the volatility trend with the amount of Ag deposition is closely investigated using transmission electron microscopy and scanning electron microscopy images. The device shows the conductance potentiation by a voltage pulse train under 1 µA current level, and the higher potentiation rate is observed in the CBRAM with thick Ag source layer. [ABSTRACT FROM AUTHOR]

In this study, silicon nanowire (SiNW) FET-based and SiNW tunnel FET (TFET)-based biosensors are co-integrated with CMOS circuits by using top-down approached and CMOS-compatible back-end process simultaneously. The possibility of multiplexed sensing is verified with the fabricated FET and TFET biosensors. For multiplexed-sensing, two separate sensing materials which react with two distinct bio-targets are formed by partially capping the gold on SiO2 film through a lift-off process. Then two bio-receptors which selectively combine to the gold and the SiO2 are deposited. After the reaction of each biomolecule to each receptor, the changes of saturation and gate-induced-drain-leakage (GIDL) currents are monitored in the FET sensor. It is experimentally confirmed that two different biomolecules are independently detectable by the changes of the saturation and the GIDL currents in the FET sensor. To solve the dependence of the gold formation position on the sensitivity as well as the large current difference between the saturation and the GIDL currents, we demonstrated the TFET biosensor which uses the changes of tunneling and ambipolar currents generated in the source and the drain end. As a result, it is clearly revealed that two different biomolecules can be detected without interference, regardless of the position of the gold layer by the changes of the tunneling and the ambipolar currents with almost equivalent sensing current level. [ABSTRACT FROM AUTHOR]

Although insertion of a thin insulating layer between metal electrodes and a semiconducting channel is an effective way to improve device performance, the exact reason for improvement in performance is not elucidated. Herein, the role of an Al2O3 interlayer sandwiched between Al metal electrodes and an amorphous indium–gallium–zinc–oxide semiconducting channel is systematically investigated. The Al2O3 interlayer results in not only a good transistor performance with increased on current but also improved gate bias stress stability. The improvement is primarily attributed to a doping effect and mitigation of interface defects. Energy‐band diagrams, experimentally obtained from temperature‐variable electrical characterization and electrostatic force microscopy, validate the channel doping effect, which increase the tunneling probability of the electron charge carriers via a reduction of the Schottky barrier width. A comprehensive study on the influence of various processing parameters, including Al2O3 thickness, post‐annealing treatment conditions, and types of electrodes, on the transistor device is also performed. This approach guides the practical implementation of stable sol–gel oxide‐based thin‐film transistors and promotes integrated circuitry applications. [ABSTRACT FROM AUTHOR]

Low operation power and high endurance of resistive random access memory (RRAM) as a synaptic device are critical parameters for in-memory computing applications. Yet, high power consumption and reliability issue of silicon bottom electrode (BE) RRAM hinder its commercialization as a synaptic device. In this experiment, we report on the improvement of switching characteristics of silicon BE nanowedge RRAM via the Nickel (Ni) silicidation process. Existing highly doped Si-BE forms a SiO2 interfacial layer (IL) during a switching layer deposition and increases an effective thickness, leading to increased voltage drop within the RRAM device and large cycle-to-cycle variations. By siliciding the Si-BE with Ni, the issue of IL formation is removed and the resistance of metallic NiSi BE is further reduced compared to Arsenic (As+) doped Si BE. Both dc and ac analyses of the fabricated NiSi-BE nanowedge RRAM have shown the reduction of overshoot and switching current down to 55% of the original value. Transmission electron microscopy (TEM) and energy-dispersive spectroscopy (EDS) analysis convinced the formation of NiSi BE. In addition, gradual switching characteristics, uniform low resistance state (LRS), and better endurance of NiSi-BE nanowedge RRAM enable the Si compatible approach to fabricate a large-size RRAM cross-point array for utilization in hardware-implemented neuromorphic computing applications. [ABSTRACT FROM AUTHOR]

Although many studies have been continuously conducted to reduce the power consumption of a resistive random access memory (RRAM) cross-point array with the current-compliance effect, it has been difficult yet to realize intrinsic self-compliance effects in an RRAM device itself. In this study, a simple oxygen-rich TiOy layer is inserted into the Al2O3/TiOx-based RRAM stack as a current suppression layer, and XPS analysis is provided to compare the stoichiometry of the TiOx and TiOy layers. A self-compliance region is formed between the different breakdown voltages of Al2O3 and TiOy layers, and a relatively thinner current path is formed in the Al2O3 layer than a device without the TiOy layer and the overall current level is significantly decreased since the TiOy layer limits the overshoot current. [ABSTRACT FROM AUTHOR]

In this Letter, we present reset-voltage-dependent precise tuning operation of TiOx/Al2O3-based memristive devices. For the high resistance state (HRS) with high reset voltage, abrupt set operations are observed with a large variation, while the HRS obtained by low reset voltage provides gradual and uniform switching behaviors. The improvement of gradual switching and the programming accuracy are analyzed regarding cycle-to-cycle as well as device-to-device variations. We believe that these results can be applied to operate TiOx/Al2O3-based memristors in areas requiring highly accurate tuning characteristics. [ABSTRACT FROM AUTHOR]

Objectives: Endoscopic transpapillary gallbladder drainage (ETGBD) has been proposed as an alternative to surgery or percutaneous cholecystostomy in patients with acute calculus cholecystitis (ACC). We aimed to evaluate the safety and efficacy of ETGBD via endoscopic transpapillary gallbladder stenting (ETGBS) or endoscopic naso-gallbladder drainage (ENGBD) as either a bridging or a definitive treatment option for patients with ACC when a cholecystectomy is delayed or cannot be performed. Methods: From July 2014 to December 2018, 171 patients with ACC in whom ETGBD were attempted were retrospectively reviewed. The technical and clinical success rates and adverse events were evaluated. Moreover, the predictive factors for technical success and the stent patency in the ETGBS group with high surgical risk were examined. Results: The technical and clinical success rates by intention-to-treat analysis for ETGBD were 90.6% (155/171) and 90.1% (154/171), respectively. Visible cystic duct on cholangiography were significant technical success predictor (adjusted odds ratio: 7.099, 95% confidence interval: 1.983–25.407, P = 0.003) as per logistic regression analysis. Adverse events occurred in 12.2% of patients (21/171: mild pancreatitis, n = 9; acute cholangitis, n = 6; post-endoscopic sphincterotomy bleeding, n = 4; and stent migration, n = 1; ACC recurrence, n = 1), but all patients were treated with conservative management and endoscopic treatment. Among the ETGBS group, the median stent patency in 70 patients with high surgical risk was 503 days (interquartile range: 404.25–775 days). Conclusions: ETGBD, using either ETGBS or ENGBD, may be a suitable bridging option for ACC patients unfit for urgent cholecystectomy. In high surgical risk patients, ETGBS may be a promising and useful treatment modality with low ACC recurrence. [ABSTRACT FROM AUTHOR]

We fabricated a silicon based nano-wedge resistive switching memory device with the stack of Ti/HfOx/p+-Si. By using 25% tetra-methyl-ammonium hydroxide (TMAH) aqueous solution, the anisotropic wet etching process is carried out to minimize the tip structure of the silicon bottom electrode to a width of 4 nm, and the structure was validated through TEM analysis. Due to the minimized device area, low read current levels (<1 μA) were obtained in the nano-wedge RRAM while the opposites were measured in large size RRAM devices. In addition, the fabricated nano-wedge RRAM exhibited low power consumption during the DC switching process. Additionally, pulse measurement and retention tests were performed to demonstrate the synaptic behaviors of long-term potentiation and depression. Software neural network simulation was followed to test the feasibility of nano-wedge RRAM's array implementation. These results demonstrate the fabricated nano-wedge RRAM devices' potential usage as a synaptic device in neuromorphic computing systems. [ABSTRACT FROM AUTHOR]

We fabricated a silicon based nano-wedge resistive switching memory device with the stack of Ti/HfOx/p+-Si. By using 25% tetra-methyl-ammonium hydroxide (TMAH) aqueous solution, the anisotropic wet etching process is carried out to minimize the tip structure of the silicon bottom electrode to a width of 4 nm, and the structure was validated through TEM analysis. Due to the minimized device area, low read current levels (<1 μA) were obtained in the nano-wedge RRAM while the opposites were measured in large size RRAM devices. In addition, the fabricated nano-wedge RRAM exhibited low power consumption during the DC switching process. Additionally, pulse measurement and retention tests were performed to demonstrate the synaptic behaviors of long-term potentiation and depression. Software neural network simulation was followed to test the feasibility of nano-wedge RRAM's array implementation. These results demonstrate the fabricated nano-wedge RRAM devices' potential usage as a synaptic device in neuromorphic computing systems. [ABSTRACT FROM AUTHOR]

In this article, we report a method for recovering a resistive-switching random access memory (RRAM) from the reset breakdown and enhancing the endurance characteristics. A SiNx-based RRAM device has been fabricated and its switching characteristics are analyzed with a particular interest in reset breakdown. It has been found that the SiNx RRAM in permanent reset breakdown can be revived to high-resistance state (HRS) by thermal recovery, a low-temperature annealing method. The memory window could be widened even with enhanced reset stability and conductance distribution. Temperature-dependent conductance change has been measured in order to figure out the substantial component of conductive filament and the mechanism of thermal recovery. The experimental evidences show that the reset breakdown process is the result of unwanted Si dangling bond (Si-DB) formation. By thermal recovery, Ni filament could be ruptured without applying a high electric field which induces negative set. [ABSTRACT FROM AUTHOR]

Background: Various core biopsy needles have previously been developed for endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB). However, the properties of needle gauge in the diagnostic outcomes of solid pancreatic lesions remain unknown. This trial compared the procurement rates of histologic cores from solid pancreatic lesions with EUS-FNB using 20- and 25-gauge (G) FNB needles.Methods: In a prospective randomized multicenter clinical trial, patients with solid pancreatic lesions underwent EUS-FNB with either a 20-gauge or a 25-gauge FNB needle. The rates of histologic core procurement, overall diagnostic accuracy, and adverse events were compared between the two groups (20-gauge or 25-gauge FNB needle).Results: In total, 88 patients (48 men, 40 women, mean age 65.7 years) were enrolled. No significant differences were found in the demographic characteristics between the two groups (20-gauge or 25-gauge FNB needle). The procurement rate of histologic cores in the 20-guage FNB needle group (41/45, 91.1%) was significantly higher than that in the 25-guage FNB needle group (32/43, 74.4%, P = 0.037). However, no significant differences were found in the overall diagnostic accuracy between 20-guage FNB needle (40/45, 88.9%) and 25-guage FNB needle (34/43, 79.1%, P = 0.208). No procedure-related adverse events were observed in either group.Conclusions: Although both FNB needles provided high overall diagnostic accuracy, the reliability of the 20-guage FNB needle is better than the 25-guage FNB needle when retrieving samples for histological analysis. [ABSTRACT FROM AUTHOR]

The guidelines for pancreatic intraductal papillary mucinous neoplasms (IPMNs) recommend surgical resection of all main-duct (MD) and mixed-type IPMNs in surgically fit patients. We conducted this study to identify the rates of high-grade dysplasia (HGD) and invasive carcinoma according to the morphological features of the main pancreatic duct (MPD) in patients with MD and mixed IPMN. We performed a retrospective study of 259 patients with histologically proven MD and mixed-type IPMNs who underwent surgery at six academic institutions. The rate of HGD and invasive carcinoma was 11.1% (24/216) in patients without enhancing mural nodules (MNs) and 69.8% (30/43) in patients with MNs. Multivariate analysis showed that MPD diameter of ≥10 mm [odds ratio (OR), 2.5; 95% confidence interval (CI), 1.155–5.505; P = 0.02], diffuse MPD dilatation (OR, 3.2; 95% CI, 1.152–8.998; P = 0.02), and presence of enhancing MNs in MPD (OR, 9.6; 95% CI, 3.928–23.833, P < 0.0001) were significant predictors of HGD and invasive carcinoma. Of the 216 patients without enhancing MNs, 79 patients (36.6%) having both segmental MPD dilatation and MPD diameter of <10 mm showed significantly lower rates of HGD and invasive carcinoma (3/79, 3.8%) than patients having both diffuse MPD dilatation and MPD diameter ≥10 mm (9/36, 25%, P = 0.001). MD and mixed-type IPMNs having segmental MPD dilatation with MPD dilation <10 mm and no enhancing MNs on imaging showed a significantly lower rate of HGD and invasive carcinoma, and watchful follow-up instead of immediate surgical resection might be possible in these patients. [ABSTRACT FROM AUTHOR]

Background: Recurrence of common bile duct stone (CBDS) is not common after laparoscopic common bile duct exploration (LCBDE). This study aimed to investigate the risk factors of recurrence of CBDS after LCBDE. Methods: Patients who underwent LCBDE between January 2001 and December 2018 in four teaching hospitals of The Catholic University of Korea were included. The operation, fluoroscopy, and endoscopic retrograde cholangiopancreatography records were investigated retrospectively. The primary outcome of this study was the independent risk factors for recurrence of CBDS. Results: A total of 230 patients were included in this study. Thirty‐one patients had recurrence of CBDS. In univariate analysis, CBDS size (>9 mm) (P = 0.003), multiple stones (≥2) (P = 0.031), stone size (≥1.5 cm) (P = 0.041), CBD diameter (≥12 mm) (P = 0.005), CBD dilatation (≥10 mm) (P = 0.02), prior history of laparoscopic cholecystectomy (P = 0.002) were associated with recurrence. After multivariable logistic regression, CBDS size (>9 mm) (OR 4.67, 95% CI 1.35–16.18, P = 0.011), CBD dilatation (≥10 mm) (OR 5.66, 95% CI 1.47–21.82, P = 0.012), and prior history of laparoscopic cholecystectomy (AOR 3. 90, 95% CI 1.34–11.37, P = 0.013) were associated with recurrence. Conclusions: Stone size >9 mm, CBD diameter ≥10 mm, and prior history of laparoscopic cholecystectomy were risk factors for recurrence of CBDS after LCBDE. [ABSTRACT FROM AUTHOR]

To develop proliposome formulations to improve the oral bioavailability of l-glutathione (GSH), GSH-loaded proliposomes were prepared using the granule method. Mannitol was selected as an effective excipient to achieve the desired particle size, entrapment efficiency (EE), and solubility for oral delivery of the final formulation. To evaluate the effect of surface charge of proliposomes on the oral bioavailability of GSH, negative (F1–F4) and positive proliposomes (F5–F9) were prepared. Particle size of F1 and F5 was 167.8 ± 0.9 and 175.9 ± 2.0 nm, and zeta potential of F1 and F5 was –8.1 ± 0.7 and 21.1 ± 2.0 mV, respectively. Encapsulation efficiency of F1 and F5 was 58.6% and 54.7%, respectively. Considering their particle size, zeta potential, and EE, the proliposomes F1 and F5 were adopted as the optimal formulations for further experiments. Solid state characterization of the proliposomes confirmed lipid coating on the surface of mannitol. The release of GSH from F1 and F5 formulations was prolonged until 24 h and pH independent. The total antioxidant capacity of GSH was concentration-dependent and maintained after formulation of GSH proliposomes. Circular dichroism spectroscopy confirmed that the molecular structure of GSH was maintained in the proliposome formulations. GSH proliposomes exhibited no significant changes in particle size and zeta potential for 4 weeks. An oral bioavailability study in rats revealed that F5 exhibited 1.05-, 1.08-, and 1.11-fold higher bioavailability than F1, commercial capsule formulation, and pure GSH, respectively. In conclusion, the prepared GSH proliposomes enhanced the poor bioavailability of GSH and prolonged its duration of action. [ABSTRACT FROM AUTHOR]