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All-implanted lateral β-Ga2O3 MOSFET devices realized on semi-insulating (-201) β-Ga2O3 substrates

In this work, we report on the fabrication of all-implanted β-Ga2O3 metal-oxide-semiconductor field-effect transistor (MOSFET) devices on semi-insulating (-201) β-Ga2O3 substrates. Through the use of multiple energy Si+ implantation and subsequent annealing, we were able to achieve high activation efficiencies up to 87% allowing to realize the active transistor channel and Ohmic contact regions with electrical properties comparable to homoepitaxial layers grown by metal-organic chemical vapor deposition. The fabricated β-Ga2O3 MOSFET devices featured excellent current modulation with on/off current ratios up to 109, maximum drain current densities of 180 mA/mm, and specific on-resistances of 1.5 mΩcm2. Furthermore, breakdown measurements in air of the non-field-plated MOSFET devices with a gate-to-drain distance of 2 μm showed a catastrophic breakdown at 332 V, which equals an average breakdown strength of 1.7 MV/cm. The outcome of this work emphasizes the high potential of this all-implantation approach for fabricating high-performing Ga2O3-based electronic devices for next-generation power electronics applications without the need of sophisticated high-quality epitaxial growth.

HybridBranchNetV2: Towards reliable artificial intelligence in image classification using reinforcement learning

Many artificial intelligence (AI) algorithms struggle to adapt effectively in dynamic real-world scenarios, such as complex classification tasks and object relationship extraction, due to their predictable but non-adaptive behavior. This paper introduces HybridBranchNetV2, an optimized hybrid architecture designed to address these challenges. The key novelty of our approach lies in the integration of reinforcement learning for adaptive feature extraction and the use of graph-based techniques to analyze object relationships in complex environments. By dynamically adjusting feature extraction based on feedback from the environment, the model improves adaptability, while graph-based methods allow for a more comprehensive analysis of object relationships. Our extensive evaluations demonstrate that HybridBranchNetV2 achieves average 91.75% accuracy over four different challenging datasets. In particular, a 14% improvement obtained on the Visual Genome dataset and ImageNet 1K compared to the original HybridBranchNet model. Additional testing on CIFAR, Flowers, and ImageNet datasets revealed improvements of 6%, 1%, and 6%, respectively. These advancements not only enhance classification accuracy but also ensure efficient computation, making HybridBranchNetV2 suitable for real-time applications with minimal risk of overfitting. The proposed framework demonstrates significant improvements in adaptability, performance, and computational efficiency, addressing critical limitations in current AI models.

Optimal scheduling of solar powered EV charging stations in a radial distribution system using opposition-based competitive swarm optimization

Terahertz near-zero reflection modulator based on cascaded electrical length reconfiguration

Return loss is a core indicator of module connectivity performance in integrated communication systems. Reflections from the modulation device can cause power fluctuations, leading to excessive amplitude noise affecting the system's signal-to-noise ratio. To solve the problem of high return loss in existing terahertz amplitude modulation techniques, this paper proposes a near-zero reflection terahertz modulator based on an electrical length reconfiguration cascade. The ON-OFF effect of the modulator is achieved through the cascade's electrical length reconstruction, and the reflections are effectively suppressed from the ON state to the OFF state. Experimental results demonstrate that the proposed modulator achieves a broadband low-reflection effect in the 170–260 GHz band, with a Voltage Standing Wave Ratio (VSWR) of less than 1.5 over a bandwidth of 60 GHz and an optimal VSWR of 1.1. It has the potential to support high-speed response as well as the large-capacity, high-rate data transmission. Accordingly, the proposed modulator offers a promising solution for the design of high-performance terahertz modulators and multi-channel integrated terahertz communication systems.

Preferential apical infection of Caco-2 intestinal cell monolayers by SARS-CoV-2 is associated with damage to cellular barrier integrity: Implications for the pathophysiology of COVID-19

SARS-CoV-2 can infect different organs, including the intestine. In an in vitro model of Caco-2 intestinal cell line, we previously found that SARS-CoV-2 modulates the ACE2 receptor expression and affects the expression of molecules involved in intercellular junctions. To further explore the possibility that the intestinal epithelium can serve as an alternative infection route for SARS-CoV-2, we used a model of polarized monolayers of Caco-2 cells (or co-cultures of two intestinal cell lines: Caco-2 and HT29) grown on the polycarbonate membrane of Transwell inserts, inoculated with the virus either in the upper or lower chamber of culture to determine the tropism of the virus for the apical or basolateral pole of these cells. In both polarized Caco-2 cell monolayers and co-culture Caco-2/HT29 cell monolayer, apical SARS-CoV-2 inoculation was found to be much more effective in establishing infection than basolateral inoculation. In addition, apical SARS-CoV-2 infection triggers monolayer degeneration, as shown by histological examination, measurement of trans-epithelial electrical resistance, and cell adhesion molecule expression. During apical infection, the infectious viruses reach the lower chamber, suggesting either a transcytosis mechanism from the apical side to the basolateral side of cells, a paracellular trafficking of the virus after damage to intercellular junctions in the epithelial barrier, or both. Taken together, these data indicate a preferential tropism of SARS-CoV-2 for the apical pole of the human intestinal tract and suggest that infection via the intestinal lumen leads to a systemic infection.

A robust deep learning framework for multiclass skin cancer classification

Enhanced stability and mobility of aligned In2O3 nanofiber field-effect transistors with Y2O3 passivation

Field-effect transistors (FETs) based on indium oxide (In2O3) nanofibers demonstrate significant potential for applications in next-generation electronic devices. However, In2O3 nanofiber FETs typically exhibit deteriorated electrical performance and bias stability due to the disordered arrangement of nanofibers and a high concentration of oxygen vacancy defects. In this study, In2O3 nanofibers were prepared by electrospinning, and the effects of nanofiber orientation and Y2O3 passivation on FET electrical performance were systematically investigated. The results indicate that after Y2O3 passivation, the aligned In2O3 nanofiber FETs exhibit enhanced electrical performance and superior positive bias stress and negative bias illumination stress stability. The Y2O3 passivation layer effectively prevents the penetration of external O2 and H2O molecules, while the diffusion of Y3+ into the back channel reduces oxygen vacancies, thereby improving device stability. When Al2O3 was employed as the dielectric layer, the electrical performance of aligned In2O3 nanofiber FET with Y2O3 passivation was further optimized, achieving a mobility of 18.2 cm2/V s and a subthreshold swing of 85 mV/dec. Meanwhile, the FET exhibits excellent environmental stability after 60 days of atmospheric exposure. This work provides a strategy for fabricating nanofiber-based FETs with high mobility and stability.

Bronchoalveolar lavage single-cell transcriptomics reveals immune dysregulations driving COVID-19 severity

The continuous threats posed by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the virus that causes COVID-19, including the emergence of potentially more infectious and deadly variants, necessitate ongoing studies to uncover novel and detailed mechanisms driving disease severity. Using single-cell transcriptomics, we conducted a secondary data analysis of bronchoalveolar lavage fluid (BALF) from COVID-19 patients of varying severities and healthy controls to comprehensively examine immune responses. We observed significant immune cell alterations correlating with disease severity. In severe cases, macrophages showed upregulation of pro-inflammatory genes TNFα and IL1β, contributing to severe inflammation and tissue damage. Neutrophils exhibited increased activation, marked by S100A8, CXCL8, and IL1β expression, with extended viability and reduced phagocytosis. Genes such as MCL1 and HIF1α supported extended viability, while MSR1 and MRC1 indicated reduced phagocytosis. Enhanced formation of neutrophil extracellular traps (NETs) and reduced clearance, indicated by NET-associated markers, were linked to thrombo-inflammation and organ damage. Both macrophages and neutrophils in severe cases showed impaired efferocytosis, indicated by decreased expression of MSR1 and TREM2 in macrophages and downregulation of FCGR3B in neutrophils, leading to the accumulation of apoptotic cells and exacerbating inflammation. Severe cases were characterized by M1 macrophages with high TNFα and IL1β, while milder cases had M2 macrophages with elevated PPARγ. Dendritic cells (DCs) in severe cases exhibited reduced proportions and attenuated expression of MHC class I genes (HLA-A, HLA-B, HLA-C) and co-stimulatory molecules (CD80, CD86), alongside increased cytochrome c expression, indicating impaired antigen presentation and enhanced apoptosis. NK and T cells in severe cases demonstrated altered receptor and gene expression, with increased activation markers IFNγ and ISG15, suggesting a paradoxical state of activation and exhaustion. This analysis highlights the critical role of dysregulated neutrophil, macrophage, dendritic cell, NK, and T cell responses in severe COVID-19, identifying potential therapeutic targets and providing novel insights into the disease.

Model sensitivity limits attribution of greenhouse gas emissions to polar bear demographic rates

Abstract Greenhouse gas emissions continue to increase and negatively affect sea ice conditions that polar bears rely on. It is therefore important to better understand how specific emissions levels affect polar bear demography. A recent study proposed a framework to address this issue, but sensitivity to decisions rules of the approach may limit its utility. We tested how sensitive the approach is to decisions rules related to sea ice concentration, choice of subpopulation boundaries, and modeling choices for bears in the Chukchi Sea and Southern Beaufort Sea subpopulations. We found that the number of ice-free days, number of fasting days, and when 10% of reproductive females exhibited recruitment failure varied considerably depending on equally-valid decisions rules versus those used in the existing study. Whereas the previous study suggested that both subpopulations surpassed the critical number of ice-free days that negatively affect recruitment, we found this threshold was never reached by the Southern Beaufort Sea subpopulation and only once for the Chukchi Sea subpopulation for the decision rules we considered. Our results suggest that the previously published approach is too sensitive to modeling assumptions and choice of decision rules to accurately evaluate the impacts of GHG emissions on polar bear demographic rates.

Anti-irradiation reinforcement in NiFe/oxide composite structure by electronic reconstruction and structural stabilization for efficient magnetoresistive sensor in aerospace/radiotherapy applications

The construction of irradiation-tolerant anisotropic magnetoresistance (AMR) sensors is crucial for weak-field detection in scenarios of aerospace and radiotherapy. Presently, the utilization of the NiFe/oxide composite structure was considered to be an effective scheme to optimize the spin-dependent transport property; however, it exhibited poor anti-irradiation ability due to the crystal instability of oxide. Here, a strategy was proposed to break through the limitation based on the electronic reconstruction and structural stabilization. By introducing an oxygen-affinitive Hf intercalation into the Ta/MgO/NiFe/MgO/Ta multilayer, the electron coordination was modified to tune the 3d orbital occupancy of Fe, apparently boosting the s-d electron scattering and spin-related transport property. Meanwhile, the irradiation stability of electronic and crystal structures was effectively improved due to the emergence of the Hf–O–Mg bond with high dissociation energy. Therefore, we constructed a highly reliable AMR sensor with both the ultrahigh sensitivity of 3.1 mV/V/Oe and excellent irradiation-tolerant ability capable of resisting the γ-ray irradiation of 1000 Gy. These results not only build an important basis for the sensor application in the irradiation environment but also provide a possible idea for the anti-irradiation design in spintronic devices.

Pathology and parasitology of free-ranging coyotes from Tennessee and South Carolina

Coyotes are exposed to many parasites and pathogens of veterinary and zoonotic concern. To assess the prevalence of the diseases caused by these microbes, we opportunistically obtained coyote samples from a variety of sources including a GPS collaring study, rabies testing facilities, wildlife resources agents, and road-side mortalities. We performed necropsies, serological testing, fecal flotations, and molecular analyses on coyotes from Tennessee and South Carolina. Dirofilaria immitis (heartworm) infected 46% (41/89) of coyotes and was associated with eosinophilic alveolitis and arteritis. Paragonimus kellicotti, a zoonotic lung fluke, was found in 24% (17/71) of Tennessee coyotes, including one coyote with extrapulmonary infection affecting the liver and lymph nodes. Trichinella spp., a zoonotic nematode, was present in 17% (12/71) of Tennessee coyotes but was not associated with muscular inflammation. Sarcoptes scabiei, the causative agent of sarcoptic mange, was detected in one Tennessee coyote. Most coyotes (86% [90/105]) were seropositive for Toxoplasma gondii, while 8.5% (9/106) were seropositive for Trypanosoma cruzi, an emerging zoonotic, vector-borne parasite. This study demonstrated that coyotes are commonly exposed to numerous parasites and pathogens that affect people and pets and are excellent sentinels for these diseases.

Vericiguat prevents high glucose-mediated impaired vascular smooth muscle cGMP production and vasorelaxation

Giant persistent photoconductivity at room temperature in Sn-based perovskites

Long avoided due to adverse effects in traditional optoelectronic devices, persistent photoconductivity (PPC) is now sought-after for emerging technologies, including artificial synapses and coupled solar batteries. We report on a giant PPC effect at room temperature in the mixed Sn/Pb-based perovskite MAPb0.5Sn0.5I3 (MA = methylammonium). Using Hall and photo-Hall measurements, we identify macroscopic separation of negative and positive carriers as the most likely origin for delayed photoconductivity decay, with a strong electron localization expected at grain boundaries or cracks within the polycrystalline films. Additionally, measurements on perovskite films with varying morphology and SnF2 additive content reveal that large apparent grain size (>5 μm) and effective passivation of recombination centers combine to provide a path for achieving PPC extending over 100 h at room temperature.

Effect of organizational change on employee innovation performance: A dual mediation model

Affected by the COVID-19 pandemic and the international development pattern, the international environment has undergone profound changes. Enterprises, as the main body of activities on the front line of production and operation and the main battlefield of market competition, are facing various risk challenges. In both domestic and international markets, these challenges are becoming increasingly complex for businesses to navigate. For theoretical research, the impact of organizational change on employee innovation performance has become a key issue in organizational behavior and human resource management research. However, the influence mechanism of organizational change on employee innovation performance is still unclear. In this study, we examine whether, how, and when organizational change increases employee innovation performance in accordance with job demands-resource theory, as well as the effect of work pressure and work engagement on employee innovation performance. Data from 289 employees at three time points are examined. The results show that: (1) Organizational change negatively affects employee innovation performance through work pressure, i.e., work pressure mediates the impact of organizational change on employee innovation performance. (2) Organizational change positively affects employee innovation performance through work engagement, i.e., work engagement mediates the impact of organizational change on employee innovation performance. (3) Organizational identity plays a moderating role between organizational change and work pressure and work engagement, respectively, and there is a moderating effect in the process of mediation of work pressure and work engagement. The findings of this study provide important insights into how and when organizational change influences employee innovation performance.

A novel in silico molecular tool for comprehensive differentiation of Mycobacterium species

Abstract The Identification of various mycobacterial species is critical for understanding their pathogenicity and epidemiology. Despite the existence of several established methods for identifying mycobacterial species, each of these methods has several significant limitations, including high costs, substantial time demands, and a restricted ability to detect a wide range of recoverable species. This study presents an in silico method using restriction fragment length polymorphism (RFLP) to differentially identify 75 clinically important mycobacterial species.The present investigation employed specific primer combinations to identify and generate a distinct hypervariable sequence across the ribosomal RNA gene. This unique sequence using appropriate restriction enzyme digestion followed by gel electrophoresis enabled the creation of highly precise and distinct patterns or profiles for each of the 75 medically relevant Mycobacterium species, including members of closely related Mycobacterium complex groups. This approach can quickly and reliably identify mycobacterial species, allowing for more timely treatment decisions and contributing to beneficial epidemiological investigations.

A controllable doping method for Ga2O3 film construction and optimized density for high-performance photodetectors

Gallium oxide (Ga2O3), a wide bandgap semiconductor, has been extensively studied for its potential applications in deep ultraviolet photodetectors and next-generation power electronic devices. To enhance the optoelectronic properties of Ga2O3 films, a controllable doping strategy is proposed in this work. Using a sol-gel method, Ga2O3 films doped with magnesium (Mg) are prepared, with the Mg concentration adjustable through the precursor solution. The results indicate that the bandgap of Ga2O3 increases with higher doping levels, while the electrical conductivity decreases proportionally. To evaluate their optoelectronic characteristics, a series of photodetectors with Mg-doped Ga2O3 active layers are fabricated. Under a 254 nm incident light, the device with an optimal doping concentration of 4.2% demonstrates the best performance, achieving the highest responsivity (R) of 1.97 A/W and a photo-dark current ratio of 2.6 × 103. Furthermore, density functional theory calculations are employed to provide a detailed analysis of the fundamental mechanisms behind the enhanced optoelectronic properties. This approach to controllable and optimized doping in Ga2O3 films shows promise for future applications in semiconductor devices.

Prevalence and determinants of poor glycemic control among diabetic chronic kidney disease patients on maintenance hemodialysis in Tanzania

Background Poor glycemic control in diabetic chronic kidney disease (CKD) patients on maintenance hemodialysis is of great challenge, resulting in increased risk of morbidity and mortality. This study aimed to determine the prevalence and determinants of poor glycemic control among diabetic CKD patients on maintenance hemodialysis. Methodology A cross-sectional study was conducted in 12 dialysis centers located in four regions of Tanzania from March to June 2023. The study population was diabetic CKD patients above 18 years on maintenance hemodialysis for three months or more. A consecutive sampling technique was used for patient recruitment, and a semi-structured questionnaire was used to collect data. The primary outcome was poor glycemic control were considered when glycated hemoglobin (HbA1c) levels were <  6% or > 8%. Statistical Package for Social Sciences (SPSS) version 23 was used for data analysis. Univariate and multivariable regression models were used to evaluate the determinants of poor glycemic control. A p-value < 0.05 was considered statistically significant. Results Out of 233 enrolled patients, the overall prevalence of poor glycemic control was 55.4%, whereby 27.0% had HbA1c < 6% and 28.33% had HbA1c > 8%. A high risk of HbA1c > 8% was observed among patients who were on antidiabetic medication (2.16 (95% CI: 1.06–4.41) p =  0.035) and those attending dialysis sessions less than 3 times a week (1.59 (95% CI: 1.02–2.48) p =  0.040). The lower risk of HbA1c < 6% was observed in patients dialyzed using glucose-containing dialysates than those dialyzed with glucose-free dialysate (0.57 (95% CI 0.36–0.87) p =  0.020). Conclusion The high prevalence of poor glycemic control among diabetic CKD patients, as revealed by this study, has significant implications. Patients on antidiabetic medication and those with less than three dialysis sessions per week are at a high risk of HbA1c > 8%. Conversely, patients dialyzed using glucose-free dialysates are at a high risk of HbA1c < 6%. Glycemic control in diabetic chronic kidney disease (CKD) patients is a great challenge due to altered glucose homeostasis, gluconeogenesis, tubular glucose reabsorption and inaccuracy of glycemic regulation metrics [1]. Furthermore, changed renal pharmacokinetics of antihyperglycemic agents (AHA), uremic milieu, and dialysis therapy also contribute to this challenge [2]. Based on the severe risk of hyperglycemia and hypoglycemia in patients with diabetic end-stage renal disease (ESRD), glycemic control is of paramount importance.

Dynamic interplay of cNHEJ and MMEJ pathways of DNA double-strand break repair during embryonic development in zebrafish

Abstract Double strand breaks (DSBs) are the most deleterious DNA lesions as they frequently result in mutations when repaired by canonical non homologous end-joining (cNHEJ) and microhomology-mediated end-joining (MMEJ). Here, we investigated the relative importance of cNHEJ and MMEJ pathways during zebrafish embryonic development. We have analyzed the expression of cNHEJ and MMEJ related genes and found that it was dynamic during development and often become increased in specific tissues. We showed that inactivation of nuclear DNA ligase 3 (nLig3) or DNA polymerase theta (Polθ), two key MMEJ factors, did not affect zebrafish development but sensitized embryos to ionizing radiations and that deficiency of Polθ, but not nLig3, profoundly alters the mutation spectrum induced during repair of Cas9-mediated DSBs. By contrast, inactivation of DNA ligase 4, required for cNHEJ, did not seem to sensitize embryos to ionizing radiations nor to affect repair of Cas9-mediated DSBs but resulted in important larval growth defects. Our study underscores the dynamic and context-dependent roles of cNHEJ and MMEJ pathways during zebrafish development, highlighting their differential requirements across developmental stages and in response to genotoxic stress.

Construction of oriented Zn (002) facets via 3D conductive frameworks for enhanced performance in fiber-based zinc-ion batteries

Zinc-ion batteries (ZIBs) are poised to play a pivotal role in the future energy storage market. However, the undesired growth of zinc dendrites and the prevalence of side reactions pose significant challenges that limit the practical application of ZIBs. The sophisticated structural design and crystal orientation of the Zn anode can effectively suppress the occurrence of zinc dendrites and side reactions. Herein, a highly oriented Zn (002) lattice plane on 3D conductive frameworks [Zn/TiN nanotubes (NTs)] is designed to address uncontrolled dendrite growth, water-induced side reactions, and suboptimal Zn metal utilization in ZIBs. By leveraging an abundance of active sites for Zn2+ adsorption, minimal charge transfer resistance, and the controlled growth of Zn crystal facets, the reversibility and stability of ZIBs can be significantly enhanced during the Zn plating/stripping process. Remarkably, fiber-ZIBs based on Zn/TiN NTs exhibit a large specific capacity, long-term cycling durability, and excellent mechanical properties. This work proposes an approach to achieve highly reversible zinc anodes from the perspective of nanostructure and crystal orientation.

Talent identification of 12-year old male Australian rules footballers: Physical advantages and prognosis for junior and senior national-level selection

Talent identification focuses on the ability to identify and select young athletes who show potential for future sporting success. The aim of this study was to compare the anthropometry and physical performance of male youth Australian Football players selected and not selected into a high performance sports academy program. Its secondary aim was to determine whether selection into a talent development environment at 12 years old affects the odds of selection into subsequent junior national level representative and senior professional Australian Football programs. 168 youth males (11.7 ± 0.4 years) who nominated for the selection process to attend a specialised high school sports academy completed a series of physical and anthropometric assessments. The data collection period occurred over seven years (2013–2019), with a prognostic period between one to ten years. Results found selected 12 years olds were taller and had greater lower body power, speed and aerobic fitness than non-selected athletes. A combination of height, aerobic fitness, and lower body power best distinguished between selected and non-selected players. This discriminant analysis had high accuracy and greater sensitivity than specificity. Further, athletes selected into the talent development environment had a much greater likelihood of being selected into junior state/national (54-fold) and senior professional (5-fold) teams than non-selected athletes. Overall, the findings demonstrate some support for the prognostic ability of selection into a talent development program at 12 years old to predict later selection in the talent pathway. These findings support the role of talent development programs in the development of male Australian footballers.