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The C-doped P-gate-enhanced HEMT (PEHEMT) is simulated by using the Silvaco T-CAD tool. The interaction among the C acceptor trap, electron and hole in the buffer layer at different voltages promotes interesting electrical characteristic within the device. In off-state conditions, the peak electric field position shifts from the edge of gate to the edge of drain. During the process of peak electric field transfer, the gate electric field gradually saturates, and the increase rate of peak electric field shows a turning point at 350V (Vd < 600 V). As the voltage further increases (Vd > 600 V), the increase rate of the drain electric field gradually slows down and tends to saturation, and the corresponding saturated gate electric field begins to increase. The uniform, quasi- linear, and step distributions of three different C acceptor in the buffer layer exhibit different degrees of current collapse under 1 ms bias stress, with values of 21.8%, 12.7%, and 12.8%, respectively. In this work, we have provided appropriate explanations for the above phenomena.

Recently, the underlying mechanism of vascular calcification (VC) has been partially elucidated. However, it is still high incidence, and no effective treatment has been found. This study aims at figuring out the underlying mechanisms of microRNA-708-5p (miR-708-5p)/sodium-phosphate transporter 1 (Pit-1) axis in high phosphate (HP)-induced VC of T/G HA-VSMCs. Alizarin Red S staining was used to evaluate calcium salt deposition, and the activity of alkaline phosphatase (ALP) was determined by measuring the absorbance at 405 nm. RT-qPCR and Western blot were performed to assess the levels of miR-708-5p and Pit-1, the levels of ALP, Pit-1, β-catenin, glycogen synthesis kinase 3 β (GSK3β), and p-GSK3β proteins, respectively. The interaction between miR-708-5p and Pit-1 was validated by luciferase reporter assay. Our findings illustrated that miR-708-5p was downregulated and Pit-1was upregulated in HP-induced VC. MiR-708-5p mimics inhibited HP-induced VC. Further experiments demonstrated that miR-708-5p targets Pit-1. In addition, miR-708-5p inactivates the Wnt8b/β-catenin pathway via targeting Pit-1 to reduce HP-induced VC. MiR-708-5p has a crucial effect on VC via targeting Pit-1 and inhibiting Wnt8b/β-catenin pathway, it may serve as a new target for VC treatment.

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has led to more than 5 million deaths worldwide to date. Due to the limited therapeutic options so far available, target-based virtual screening with LC/MS support was applied to identify the novel and high-content compounds 1–4 with inhibitory effects on SARS-CoV-2 in Vero E6 cells from the plant Dryopteris wallichiana. These compounds were also evaluated against SARS-CoV-2 in Calu-3 cells and showed unambiguous inhibitory activity. The inhibition assay of targets showed that compounds 3 and 4 mainly inhibited SARS-CoV-2 3CLpro, with effective Kd values. Through docking and molecular dynamics modeling, the binding site is described, providing a comprehensive understanding of 3CLpro and interactions for 3, including hydrogen bonds, hydrophobic bonds, and the spatial occupation of the B ring. Compounds 3 and 4 represent new, potential lead compounds for the development of anti-SARS-CoV-2 drugs. This study has led to the development of a target-based virtual screening method for exploring the potency of natural products and for identifying natural bioactive compounds for possible COVID-19 treatment.

Hematocrit, a commonly used hematological indicator, is a simple and easily applicable test. As a marker of anisocytosis and anemia, it indicates the percentage of blood cells per unit volume of whole blood. This study aimed to evaluate the association between the level of the hematocrit at admission and preoperative deep vein thrombosis (DVT) in hip fractures of older people. We collected the demographic and clinical characteristics of patients with geriatric hip fractures between 1 January 2015, and 30 September 2019, at the largest trauma center in northwestern China. Doppler ultrasonography was used to diagnose DVT. The correlation between hematocrit levels at admission and preoperative DVT was assessed using linear and nonlinear multivariate logistic regression, according to the adjusted model. All analyzes were performed using EmpowerStats and R software. In total, 1840 patients were included in this study, of which 587 patients (32%) had preoperative DVT. The mean hematocrit level was 34.44 ± 5.64 vol%. Linear multivariate logistic regression models showed that admission hematocrit levels were associated with preoperative DVT (OR = 0.97, 95% CI: 0.95–0.99; p = 0.0019) after adjustment for confounding factors. However, the linear association was unstable, and nonlinearity was identified. An admission hematocrit level of 33.5 vol% was an inflection point for the prediction. Admission hematocrit levels 33.5 vol% were associated with preoperative DVT (OR = 0.94, 95% CI: 25 0.91–0.97, p = 0.0006). Hematocrit levels at admission were nonlinearly associated with preoperative DVT, and hematocrit at admission was a risk factor for preoperative DVT. However, the severity of a low hematocrit was not associated with preoperative DVT when the hematocrit was

Objective: The present study aimed to evaluate the association between hematocrit (HCT) levels and all-cause mortality in geriatric hip fractures. Methods: Older adult patients with hip fractures were screened between January 2015 and September 2019. The demographic and clinical characteristics of these patients were collected. Linear and nonlinear multivariate Cox regression models were used to identify the association between HCT levels and mortality. Analyses were performed using EmpowerStats and the R software. Results: A total of 2589 patients were included in this study. The mean follow-up period was 38.94 months. Eight hundred and seventy-five (33.8%) patients died due to all-cause mortality. Linear multivariate Cox regression models showed that HCT level was associated with mortality (hazard ratio [HR] = 0.97, 95% confidence interval [CI]: 0.96–0.99, p = 0.0002) after adjusting for confounding factors. However, the linear association was unstable and nonlinearity was identified. A HCT level of 28% was the inflection point for prediction. A HCT level of 28% was not a risk factor for mortality (HR = 0.99, 95% CI: 0.97–1.01, p = 0.3792). We found that the nonlinear association was very stable in the propensity score-matching sensitivity analysis. Conclusions: The HCT level was nonlinearly associated with mortality in geriatric hip fracture patients and could be considered a predictor of mortality in these patients. Registration: ChiCTR2200057323.

The aim of this study was to investigate the changes in type II neuregulin-1 (NRG-1) during the regeneration process following autologous sciatic nerve transplantation in rats.A total of 40 Sprague-Dawley(SD) rats were randomly divided into an experimental and control group. There were 20 rats in each group.Five time points were set on the 3rd, 7th, 14th, 21st and 28th days after surgery. In the experimental group, reversed autologous transplantation of the sciatic nerve was performed, while in the control group, the sciatic nerve was only exposed. Changes in the rat footprints were observed at different time points, the sciatic functional index(SFI) was calculated, regeneration of the myelin sheath were observed by transmission electron microscopy, type II NRG-1 protein were detected by western blotting, and type II NRG-1 mRNA were detected by real-time PCR.The SFI of the experimental group was lower than that of the control group at all time points after surgery, and the SFI of the experimental group was gradually increased. The expression of type II NRG-1 protein in the experimental group was significantly increased on the 3rd day, peaking on the 7th day, and continued until the 28th day after surgery. The area of medullated nerve fibers(um2) in the experimental group was significantly different from that in the control group on the 7th, 14th, 21st and 28th days(P 0.01).Type II NRG-1 peaked between the 3rd day and 14th day after autologous nerve transplantation and was probably involved in the regulation of myelin sheath regeneration during this period.

Background. During total knee arthroplasty (TKA), surgeons mobilize the patella to facilitate clear visualization of the articular surfaces and allow better prosthesis placement. According to the manipulation, this manipulation can be divided into patellar eversion and noneversion. However, the effect of patellar eversion in TKA is controversial, with substantial variability in clinical practice. This systematic review is aimed at assessing the adverse effects of patellar eversion and patellar noneversion duration in TKA. Methods. This updated systematic literature review identified randomized controlled trials comparing patellar eversion and noneversion durations in TKA. Two investigators independently extracted data and evaluated the quality of the studies. A meta-analysis was performed using RevMan version 5.3. Results. Nine studies with a total of 608 patients (730 knees) were included. Of these, 374 knees were classified in the eversion group and 356 knees in the noneversion group. The quality of the studies was high. The results showed that patellar eversion could increase the postoperative complication rate ( relative risk RR = 1.67 ; 95% confidence interval [CI], 1.09–2.54; P = 0.02 ) and postoperative pain before discharge ( mean deviation MD = 0.19 ; 95% CI, 0.04–0.34; P = 0.01 ), compared to noneversion. Additionally, patellar eversion could prolong the time until the patient is able to raise the leg while straightened ( MD = 0.42 ; 95% CI, 0.24–0.59; P < 0.00001 ) and increase the length of stay ( MD = 0.65 ; 95% CI, 0.05–1.25; P = 0.03 ). However, patellar eversion did not influence postoperative pain at 1 year ( MD = 0.02 ; 95% CI, -0.23–0.28; P = 0.85 ), operative time ( MD = − 2.66 ; 95% CI, -8.84–3.52; P = 0.40 ), recovery of quadriceps force throughout the follow-up period, and Insall–Salvati ratio ( MD = − 0.04 ; 95% CI, [-0.11–0.02]; P = 0.23 ). Conclusions. The patellar eversion could increase the postoperative complication rate and postoperative pain. Current evidence supports the avoidance of patellar eversion in TKA. Further large-sample and long-term trials are required to validate these results.

Objective: To observe the significance of subchondral bone microfracture in the human osteoarthritic tibial plateau on cartilage tidemark drift.Methods: Human knee tibial plateau cartilage samples with different OARSI grades were obtained, and the numbers of cartilage tidemarks and microfracture lines were determinedafter safranin O staining and compared among groups. Osteogenesis caused by microfracture in subchondral bone was observed and staged according to biological properties.Immunohistochemistry, western blotting, PCR and laser microdissection were performedto detect the biological properties of osteogenic areas caused by microfractures.The accompanying relationship between the ossification process and new tidemark formation inosteogenic areas caused by microfractures was then evaluated.Results: With the increase in OARSI grade, the numbers of cartilage tidemarks and subchondral bone microfracture lines in human knee tibial plateau cartilage tissue samples showed increasing trends.The subchondral bone microfracture line was observed toextend as far asthe basal area of hyaline cartilage and cause endochondral osteogenesis.The endochondral osteogenesis caused by subchondral microfracture was categorized into chondrocyte,calcareous sedimentary and ossification stages. A new tidemark appeared in the osteogenic region near the hyaline cartilage when the ossification process of the osteogenic region was completed.Conclusions:Endochondral osteogenesis canoccur at the base of hyaline cartilage induced by microfractures in the tibial plateau subchondral bone. A new cartilage tidemark can form on the side of the osteogenic tissue close to hyaline cartilage when the process of osteogenesis is completed.There is a positive correlation between the degree of cartilage tissue degeneration and the number of tidemarks in articular cartilage.

Objective: CA-125 is widely used as biomarker of ovarian cancer. However, CA-125 suffers low accuracy. We developed a hybrid analytical model, the Ovarian Cancer Decision Tree (OCDT), employing a two-layer decision tree, which considers genetic alteration information from cell-free DNA along with CA-125 value to distinguish malignant tumors from benign tumors. Methods: We consider major copy number alterations at whole chromosome and chromosome-arm level as the main feature of our detection model. Fifty-eight patients diagnosed with malignant tumors, 66 with borderline tumors, and 10 with benign tumors were enrolled. Results: Genetic analysis revealed significant arm-level imbalances in most malignant tumors, especially in high-grade serous cancers in which 12 chromosome arms with significant aneuploidy ( PConclusions: The results suggested that genetic variations extracted from cfDNA can be combined with CA-125, and together improved the differential diagnosis of malignant from benign ovarian tumors. The model would aid in the pre-operative assessment of women with adnexal masses. Future clinical trials need to be conducted to further evaluate the value of CScore in clinical settings and search for the optimal threshold for malignancy detection.

In a hybrid coupled wall (HCW), a steel coupling beam with a good shear performance can replace a concrete coupling beam. This is especially applicable for locations in which height restrictions do not permit the use of deep reinforced concrete beams or in which it is not possible to economically develop required capacity, stiffness, or deformation demands with concrete beams. In this study, a new type of connection design with a steel boundary element of hybrid coupled wall (SBE-HCW) was proposed, and a 23-story SBE-HCW structure was analyzed under both gravity and seismic load to examine the seismic performance using ABAQUS. The structural failure process, base shear force, vertex displacement, and damage distribution of core tube were investigated. The analysis results confirmed that the response of specimen exhibited good plastic deformation behavior under seismic, thereby satisfying the demands of seismic ductility design. The connection between the steel coupling beams and the shear walls in the specimen appeared to be intact. The analysis evidence indicated that the proposed connection detailing appeared to be effective.

Over the last few decades, transition metal-catalyzed direct C-H activation with the assistance of a coordinating directing group has emerged as an atom- and stepeconomical synthetic tools to transform C–H bonds into carbon-carbon or carbonheteroatom bonds. Although the strategies involving regioselective C–H cleavage assisted by various directing groups have been extensively reviewed in the literature, we now attempt to give an overview of the recent advances on phosphorus-containing functional group assisted C-H activation reactions catalyzed by transition-metal catalysts including mechanistic study and synthetic applications. The discussion is directed towards C-H olefination, C-H activation/cyclization, C-H arylation, C-H amination, C-H hydroxylation and acetoxylation as well as miscellaneous C-H activation.

Objective This study aims to develop an artificial intelligence-based method to screen patients with left ventricular ejection fraction (LVEF) of 50% or lesser using electrocardiogram (ECG) data alone. Methods Convolutional neural network (CNN) is a class of deep neural networks, which has been widely used in medical image recognition. We collected standard 12-lead ECG and transthoracic echocardiogram (TTE) data including the LVEF value. Then, we paired the ECG and TTE data from the same individual. For multiple ECG-TTE pairs from a single individual, only the earliest data pair was included. All the ECG-TTE pairs were randomly divided into the training, validation, or testing data set in a ratio of 9:1:1 to create or evaluate the CNN model. Finally, we assessed the screening performance by overall accuracy, sensitivity, specificity, positive predictive value, and negative predictive value. Results We retrospectively enrolled a total of 26 786 ECG-TTE pairs and randomly divided them into training (n = 21 732), validation (n = 2 530), and testing data set (n = 2 530). In the testing set, the CNN algorithm showed an overall accuracy of 73.9%, sensitivity of 69.2%, specificity of 70.5%, positive predictive value of 70.1%, and negative predictive value of 69.9%. Conclusion Our results demonstrate that a well-trained CNN algorithm may be used as a low-cost and noninvasive method to identify patients with left ventricular dysfunction.

Objective. Adding vitamin E to highly cross-linked polyethylene liners is frequently performed in clinical practice, aiming at reducing liner wear, increasing liner survival, and delaying revision surgery. This study is aimed at evaluating the revision rate, total femoral head penetration, and postoperative clinical function of highly cross-linked polyethylene liners with and without vitamin E in total hip arthroplasty. Methods. We conducted a systematic literature search to identify the use of highly cross-linked vitamin E liners compared to other liners in patients who received total hip arthroplasty (THA) before April 2021. The study quality assessment and data collection were conducted by two independent reviewers. Studies were artificially grouped, and vitamin E-enhanced liners (VE-PE) were compared with vitamin E-free liners (non-VE-PE). Analyses were executed using Review Manager version 5.4.1. Results. From the preliminary screening of 568 studies, fourteen studies met the research criteria. Compared to non-VE-PE, using VE-PE reduced the all-cause revision rate ( odds ratio = 0.54 ; 95% confidence interval (CI) 0.40, 0.73; P < 0.0001 ). The total femoral head penetration of the VE-PE was lower than that of the non-VE-PE ( mean difference = − 0.10 ; 95% CI -0.17, -0.03; P = 0.007 ). However, there was no difference in clinical function, including the Harris Hip Score and EuroQol Five-Dimension Questionnaire scores. Conclusion. Compared to the liners without vitamin E, the addition of vitamin E to liners could reduce the all-cause revision rate by approximately 46% in the short-term follow-up. In addition, even though addition of vitamin E could also slow down femoral head penetration, there is no contribution to clinical function.

Background This study aimed to investigate the trend of cardiovascular disease (CVD)-specific mortality in patients with non-small cell lung cancer (NSCLC) and identify prognostic factors for CVD-specific death in stage NSCLC patients. Methods In this study, 270,618 NSCLC patients were collected from the Surveillance, Epidemiology, and End Results database. CVD- and NSCLC-specific cumulative mortality and proportion of death were calculated and graphically displayed to describe the probability of specific endpoints. Prognostic factors for CVD-specific mortality were evaluated by cause-specific hazard ratios (HR) with 95% confidence intervals (CI) using the competing risk model with non-cardiovascular death as competing risks. Results Among all competing causes of death, lung cancer resulted in the highest cumulative mortality, followed by CVDs and other causes. In the proportion of cause-specific death, heart diseases accounted for approximately 5.3% of the total death, only secondary to primary cancer. In all three stages, higher age, squamous cell carcinoma, and no-or-unknown chemotherapy and/or radiotherapy were associated with a higher risk of CVD-specific death, while surgery treatment seemed to be a protective factor. Female gender was statistically related to CVD-specific death in stage I and III patients with HRs of 0.84 (0.78–0.91) and 0.84 (0.77–0.93), respectively. Interestingly, right-sided laterality was correlated with lower CVD-specific mortality with HR of 0.82 (0.74–0.90) in stage III. Conclusions This study illustrated the historical trend of CVD-specific death in NSCLC patients and assesses potential prognostic risk factors, highlighting the involvement of cardio-oncology teams in cancer treatment to provide optimal comprehensive care and long-term surveillance for cancer patients.

Objectives: COVID-19 remains a global challenge. Corticosteroids are a group of anti-inflammatory and suppressive immune response drugs that are widely used in the treatment of COVID-19, especially when it presents with viral pneumonia. Comprehensive reviews investigating the comparative proportion and efficacy of corticosteroid use are scarce. Therefore, we conducted a systematic review and meta-analysis of clinical trials to evaluate the proportion and efficacy of corticosteroid use for the treatment of COVID-19.Methods: We conducted a comprehensive literature review of PubMed, EMBASE, the Cochrane Controlled Trials Registry, and the China Academic Journal Network Publishing Database for relevant trials on glucocorticoid therapy in COVID-19 patients. Outcome measures were the proportion of patients administered corticosteroids, viral clearance and mortality. Effect size was reported as weighted mean differences (WMDs) for continuous outcomes and odds ratios (ORs) for dichotomous outcomes with associated 95% confidence intervals (CIs).Results: Forty-three trials involving 6603 patients were included. The meta-analysis demonstrated that the proportion of COVID-19 patients who received corticosteroids was significantly lower than that of patients who did not receive corticosteroids. In addition, our meta-analysis demonstrated no significant difference in the proportions of severe and nonsevere patients who were administered corticosteroids. We also performed subgroup analyses stratified by severity, indicating that the proportion of patients administered corticosteroids was significantly higher among intensive care unit (ICU) patients than among non-ICU patients. The results of our meta-analysis indicated that corticosteroid treatment significantly delayed the viral clearance time. Finally, our meta-analysis demonstrated no significant difference between the use of corticosteroids for COVID-19 patients who died and those who survived. This result indicated that mortality was not correlated with corticosteroid therapy.Conclusion: The proportion of COVID-19 patients who received corticosteroids was significantly lower than that of patients who did not receive corticosteroids. Corticosteroid use in subjects with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections delayed virus clearance and did not convincingly improve survival;therefore, corticosteroids should be used with caution in the treatment of COVID-19.

Quercetin has attracted more attention in recent years due to its protective role against ischemia/reperfusion injury. Quercetin can alleviate oxidative stress injury through the inhibition of NADPH oxidase and xanthine oxidase, blockage of the Fenton reaction, and scavenging of reactive oxygen species. Quercetin can also exert anti-inflammatory and anti-apoptotic effects by reducing the response to inflammatory factors and inhibiting cell apoptosis. Moreover, it can induce vasodilation effects through the inhibition of endothelin-1 receptors, the enhancement of NO stimulation and the activation of the large-conductance calcium-activated potassium channels. Finally, Quercetin can also antagonize the calcium overload. These multifaceted activities of Quercetin make it a potential therapeutic alternative for the treatment of ischemia/reperfusion injury.

The dislocation slip behaviors in GaN bulk crystal are investigated by nanoindentation, the dislocation distribution patterns formed around an impress are observed by cathodoluminescence (CL) and cross-sectional transmission electron microscope (TEM). Dislocation loops, vacancy luminescence, and cross-slips show hexagonal symmetry around the 〈11-20〉 and 〈1-100〉 direction on c-plane. It is found that the slip planes of dislocation in GaN crystal are dominated in {0001} basal plane and {10-11} pyramid plane. According to the dislocation intersection theory, we come up with the dislocation formation process and the related mechanisms are discussed.

Organic-inorganic hybrid perovskite materials offer the potential for realization of low-cost and flexible next-generation solar cells fabricated by low-temperature solution processing. Although efficiencies of perovskite solar cells have dramatically improved up to 22.1% within the past 6 years, there is still considerable room for further improvement in device efficiency through development of smooth and large grain size perovskite films. Commonly, the smooth perovskite layers and large grains are alternative to CH3NH3PbI3-xClx. However, the previous one-step fabrication of CH3NH3PbI3-xClx using PbCl2 needs long annealing time. Herein, the active layer, a noncontinuous CH3NH3PbI3-xClx film with micrometre-level crystalline grain, was fabricated using a one-step spin-coating process followed by high-temperature annealing and exhibited an increased efficiency of 9.93%. This finding enables the formation of larger grain size perovskite films and the demonstration of efficient perovskite heterojunction solar cells.