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Abstract To explore the clinical characteristics of patients infected with SARS-CoV-2 nationwide, especially the effect factors of asymptomatic infection and disappearance of clinical symptoms. A total of 66,448 COVID-19 patients in China who have been diagnosed by nucleic acid test or rapid antigen test were surveyed online (December 24, 2022 to January 16, 2023). Our cross-sectional study used descriptive analyses and binary Logistics regression model to assess the correlation between the clinical characteristics and relative factors, including age, gender, pre-existing conditions, reinfection, vaccination and treatment. A total of 64,515 valid questionnaires were collected. Among included participants, 5969 of which were asymptomatic. The symptoms were mainly upper respiratory symptoms, including dry and itchy throat (64.16%), sore throat (59.95%), hoarseness (57.90%), nasal congestion (53.39%). In binary Logistics regression model, we found that male, no pre-existing conditions, reinfection and vaccination have positive correlations with the appearance of asymptomatic COVID-19 patients. In Cox proportional-hazards regression model, considering all clinical symptoms disappeared in 14 days as outcome, we found that ≤ 60 years old, male, no pre-existing conditions, vaccination and adopted treatment have positive correlations with rapid amelioration of clinical symptoms in COVID-19 patients. The clinical symptoms of the participants were mainly upper respiratory symptoms which were according with the infection of Omicron variant. Factors including age, gender, pre-existing conditions and reinfection could influence the clinical characteristics and prognosis of COVID-19 patients. Importantly, vaccination has positive significance for the prevention and treatment of COVID-19. Lastly, the use of Chinese medicine maybe beneficial to COVID-19 patients, however, reasonable guidance is necessary.

Abstract Cervical cancer (CC) is a prevalent gynecological cancer worldwide that significantly impacts the quality of life and the physical and mental well-being of women. However, there have been limited studies utilizing Mendelian randomization (MR) analysis to investigate the connection between immune cells and CC. This study is to investigate the causal effects of immune traits on CC and non-neoplastic conditions of the cervix. The GWAS data for 731 immunophenotypes and six GWAS data for CC from the FinnGen database were downloaded. Subsequently, a two-sample MR analysis was conducted using the MR Egger, Weighted median, Inverse variance weighted (IVW), Simple mode, and Weighted mode methods. Our study has identified the potential causal effects of immune traits on inflammatory diseases of the cervix, other noninflammatory disorders of the cervix uteri, carcinoma in situ of cervix uteri, adenocarcinomas of cervix, squamous cell neoplasms and carcinoma of cervix, as well as malignant neoplasm of the cervix uteri, with the respective numbers being 8, 6, 11, 8, 23, and 12, respectively. A strong correlation between classic monocytes and various cervical diseases was revealed. Furthermore, we discovered that B cells expressing BAFF-R have the ability to impede the advancement of malignant CC, specifically squamous cell neoplasms and carcinoma of cervix. Our study has demonstrated a significant association between immune traits and both CC and non-neoplastic conditions of the cervix through two-sample Mendelian randomization, providing valuable insights for future clinical research.

Abstract In this paper, a double-layer patterned graphene-based frequency-selective absorber (DGFSA) is proposed as a means of reducing an antenna’s radar cross-section (RCS) while simultaneously increasing its gain. The antenna consists of a patch antenna with Multi-Graphene Frequency Selective Absorber (MGFSA) mounted on top. The DGFSA consists of double-layer patterned graphene and a band-pass frequency selective surface (FSS). Two patterned graphene lossy layers with different square resistances are used, which broaden the electromagnetic (EM) wave absorption bandwidth of the DGFSA, thus greatly reducing the out-band monostatic RCSs of the patch antenna. Meanwhile, due to the quasi-Fabry-Perot (F-P) effect, the gain of the proposed antenna is enhanced by 2.4 dB. Additionally, the low-RCS antenna reduces the monostatic RCS from 1.32 to 17 GHz under y-polarization and from 1.4 to 16.8 GHz under x-polarization, respectively. Furthermore, a decrease in the bistatic RCS is accomplished. Results from simulations and measurements match up nicely, which means the antenna we proposed has a good application on the stealth platform.

Abstract Evidence from histopathology and clinical imaging suggest that choroidal anatomy and hemodynamic perfusion are among the earliest changes in retinal diseases such as age-related macular degeneration (AMD). However, how inner choroidal anatomy affects hemodynamic perfusion is not well understood. Therefore, we sought to understand the influences of choroidal microvascular architecture on the spatial distribution of hemodynamic parameters in choriocapillaris from human donor eyes using image-based computational hemodynamic (ICH) simulations. We subjected image-based inner choroid reconstructions from eight human donor eyes to ICH simulation using a kinetic-based volumetric lattice Boltzmann method to compute hemodynamic distributions of velocity, pressure, and endothelial shear stress. Here, we demonstrate that anatomic parameters, including arteriolar and venular arrangements and intercapillary pillar density and distribution exert profound influences on inner choroidal hemodynamic characteristics. Reductions in capillary, arteriolar, and venular density not only reduce the overall blood velocity within choriocapillaris, but also substantially increase its spatial heterogeneity. These first-ever findings improve understanding of how choroidal anatomy affects hemodynamics and may contribute to pathogenesis of retinal diseases such as AMD.

Abstract Uridine, a pyrimidine nucleoside, is crucial in the synthesis of metabolites. According to observational studies, a higher plasma uridine level is associated with a lower risk of atrial fibrillation (AF). However, the casual relationship between uridine and AF is still unknown. In this study, we used the Mendelian randomisation (MR) approach to explore causality. Three genetic variants associated with uridine were identified from the Metabolomics GWAS server (7824 participants); summary-level datasets associated with AF were acquired from a genome-wide association study (GWAS) meta-analysis with 1,030,836 European participants (60,620 AF cases). We duplicated the MR analyses using datasets from AF HRC studies and the FinnGen Consortium, and then conducted a meta-analysis which combined the main results. The risk of AF was significantly associated with the genetically determined plasma uridine level (odds ratio [OR] 0.27; 95% confidence interval [CI] 0.16, 0.47; p = 2.39 × 10–6). The association remained consistent in the meta-analysis of the various datasets (OR 0.27; 95% CI 0.17, 0.42; p = 1.34 × 10–8). In conclusion, the plasma uridine level is inversely associated with the risk of AF. Raising the plasma uridine level may have prophylactic potential against AF.

Abstract Studies have demonstrated that exercise benefits executive function. However, it remains unclear which type of exercise is optimal for preserving executive function among young adults and the cerebral blood flow (CBF) mechanisms that underlie exercise-induced cognitive benefits. Therefore, this study aims to compare the intervention effects of high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) on executive function and the CBF mechanism. This was a double-blinded, randomized, controlled trial study conducted between October 2020 and January 2021 (ClinicalTrials.gov identifier: NCT04830059). Ninety-three healthy young adults (25.23 ± 2.18 years old; 49.82% male) were randomized into the HIIT (N = 33), MICT (N = 32), and control (N = 28) groups. Participants in exercise groups were guided to perform 40 min of HIIT and MICT three times a week for 12 weeks, while the control group received health education for the same period. The primary outcomes, changes in executive function assessed by the trail-making test (TMT), and CBF measured by transcranial Doppler flow analyzer (EMS-9WA), were evaluated before and after the interventions. The time taken to complete the TMT task improved significantly in the MICT group compared to the control group [β = −10.175, 95%, confidence interval (CI) = −20.320, −0.031]. Additionally, the MICT group showed significant improvements in the pulsatility index (PI) (β = 0.120, 95% CI = 0.018, 0.222), resistance index (RI) (β = 0.043, 95% CI = 0.005, 0.082), and peak-systolic/end-diastolic velocity (S/D) (β = 0.277, 95% CI = 0.048, 0.507) of CBF compared to the control group. The time taken to complete the TMT was associated with the velocity of peak-systolic (F = 5.414, P = 0.022), PI (F = 4.973, P = 0.012), and RI (F = 5.845, P = 0.006). Furthermore, the accuracy of TMT was associated with PI (F = 4.797, P = 0.036), RI (F = 5.394, P = 0.024), and S/D (F = 4.312, P = 0.05) of CBF. A 12-week MICT intervention improved CBF and executive function more effectively than HIIT among young adults. Furthermore, the findings suggest that CBF was one of the potential mechanisms underlying the cognitive benefits of exercise in young people. These results provide practical evidence supporting the promotion of regular exercise to maintain executive function and improve brain health.

Abstract Spectral technology is theoretically effective in diagnosing N stress in maize (Zea mays L.), but its application is affected by varietal differences. In this study, the responses to N stress, leaf N spectral diagnostic models and the differences between two maize varieties were analysed. The variety “Jiyu 5817” exhibited a greater response to different N stresses at the 12-leaf stage (V12), while “Zhengdan 958” displayed a greater response in the silking stage (R1). Correlation analysis showed that the spectral bands more sensitive to leaf N content were 548–556 nm and 706–721 nm at the V12 stage in “Jiyu 5817” and 760–1142 nm at the R1 stage in “Zhengdan 958”. An N spectral diagnostic model that considers the varietal effect improves the model fit and root mean square error (RMSE) with respect to the model without it by 10.6% and 29.2%, respectively. It was concluded that the V12 stage for “Jiyu 5817” and the R1 stage for “Zhengdan 958” were the best diagnostic stages and were more sensitive to N stress, which can further guide fertilization decision-making in precision fertilization.

Abstract The emergence of Omicron variant raises great concerns because of its rapid transmissibility and its numerous mutations in spike protein (S-protein). S-protein can act as a pathogen-associated molecular pattern and complement activator as well as antigen. We compared some immune characteristics of trimer S-proteins for wild type (WT-S) and B.1.1.529 Omicron (Omicron-S) to investigate whether the mutations have affected its pathogenicity and antigenic shift. The results indicated that WT-S and Omicron-S directly activated nuclear factor-κB (NF-κB) and induced the release of pro-inflammatory cytokines in macrophages, but the actions of Omicron-S were weaker. These inflammatory reactions could be abrogated by a Toll-like receptor 4 antagonist TAK-242. Two S-proteins failed to induce the production of antiviral molecular interferon-β. In contrast to pro-inflammatory effects, the ability of two S-proteins to activate complement was comparable. We also compared the binding ability of two S-proteins to a high-titer anti-WT-receptor-binding domain antibody. The data showed that WT-S strongly bound to this antibody, while Omicron-S was completely off-target. Collectively, the mutations of Omicron have a great impact on the pro-inflammatory ability and epitopes of S-protein, but little effect on its ability to activate complement. Addressing these issues can be helpful for more adequate understanding of the pathogenicity of Omicron and the vaccine breakthrough infection.

Abstract Assessing the stability characteristics of high rock slope under rainfall via theoretical research, numerical simulation, and field monitoring is of great implications for safety construction in open-pit mine engineering. Thus, based on the Hoke-Brown criterion, instantaneous internal friction angle and cohesion of high-slope rock mass under high stress conditions were deduced, and a nonlinear strength reduction method for high rock slope was established. The safety factors of the open-pit mine were calculated by COMSOL Multiphysics, which considering the high rock southwest slope and detected rainfall in Dagushan Open-pit Mine, China. The results showed that high rock slope stability could be more accurately analyzed by the proposed method due to its full consideration of slope stress state effect compared with the equivalent Mohr- Coulomb method. When the slope is low, the difference between the calculation results of the equivalent Mohr- Coulomb method and the proposed method is small, but with the increase of the slope height, the difference between the two calculation results gradually increases. When the transient saturated is formed in the slope surface layer and gradually increases, the reduction rate of the factor of safety (FOS) gradually increases. When the total rainfall is the same, the effect of short-term heavy rainfall on slope stability is less than that of long-term ordinary rainfall. The results obtained form this work provided important insights into the stability of high rock slope and rainfall infiltration in open-pit mine, and the safety factor is crucial for guiding the mining process design.

Abstract Image-based computational fluid dynamics (CFD) has become a new capability for determining wall stresses of pulsatile flows. However, a computational platform that directly connects image information to pulsatile wall stresses is lacking. Prevailing methods rely on manual crafting of a hodgepodge of multidisciplinary software packages, which is usually laborious and error-prone. We present a new computational platform, to compute wall stresses in image-based pulsatile flows using the volumetric lattice Boltzmann method (VLBM). The novelty includes: (1) a unique image processing to extract flow domain and local wall normality, (2) a seamless connection between image extraction and VLBM, (3) an en-route calculation of strain-rate tensor, and (4) GPU acceleration (not included here). We first generalize the streaming operation in the VLBM and then conduct application studies to demonstrate its reliability and applicability. A benchmark study is for laminar and turbulent pulsatile flows in an image-based pipe (Reynolds number: 10 to 5000). The computed pulsatile velocity and shear stress are in good agreements with Womersley's analytical solutions for laminar pulsatile flows and concurrent laboratory measurements for turbulent pulsatile flows. An application study is to quantify the pulsatile hemodynamics in image-based human vertebral and carotid arteries including velocity vector, pressure, and wall-shear stress. The computed velocity vector fields are in reasonably well agreement with MRA (magnetic resonance angiography) measured ones. This computational platform is good for image-based CFD with medical applications and pore-scale porous media flows in various natural and engineering systems.

Abstract Based on a new elastic clump model, a flexible membrane is proposed for the discrete element numerical simulations of triaxial tests. Conversional triaxial tests of sandstone under the confining pressures of 2 MPa and 8 MPa were carried out, in order to validate the effectiveness of the proposed numerical simulation method. The numerical model is validated by comparing the numerical results with the test results. The deformation and failure process of numerical model is analyzed by stress–strain curves, micro fractures, displacement fields, stress fields and energy fields. The model shows an X-shape shear failure zone, of which the angle is very close to that of the test; the dip angle of most shear fractures is close to the angle of the internal friction; and there is a large amount of slipping frictional heat generated on the failure surface. During the loading process, the stress chain and stress concentration appear in the middle of the model, which lead to displacement zoning in the model. The failure of the model is associated with the growth of the micro tensile- and shear fractures. This study provides an effective tool for the macro–micro investigation of rock failure processes.

Abstract Tramadol is an opioid used as an analgesic for treating moderate or severe pain. The long-term use of tramadol can induce several adverse effects. The toxicological mechanism of tramadol abuse is unclear. Limited literature available indicates the change of proteomic profile after chronic exposure to tramadol. In this study, we analyzed the proteomic and metabolomic profile by TMT-labeled quantitative proteomics and untargeted metabolomics between the tramadol and the control group. Proteomic analysis revealed 31 differential expressed serum proteins (9 increased and 22 decreased) in tramadol-treated mice (oral, 50 mg/kg, 5 weeks) as compared with the control ones. Bioinformatics analysis showed that the dysregulated proteins mainly included: enzyme inhibitor-associated proteins (i.e. apolipoprotein C-III (Apoc-III), alpha-1-antitrypsin 1–2 (Serpina 1b), apolipoprotein C-II (Apoc-II), plasma protease C1 inhibitor, inter-alpha-trypsin inhibitor heavy chain H3 (itih3)); mitochondria-related proteins (i.e. 14-3-3 protein zeta/delta (YWHAZ)); cytoskeleton proteins (i.e. tubulin alpha-4A chain (TUBA4A), vinculin (Vcl)). And we found that the differential expressed proteins mainly involved in the pathway of the protein digestion and absorption. Metabolomics analysis revealed that differential expressed metabolites mainly involved in protein ingestion and absorption, fatty acid biosynthesis, steroid hormone biosynthesis and bile secretion. Our overall findings revealed that chronic exposure to tramadol changed the proteomic and metabolomic profile of mice. Moreover, integrated proteomic and metabolomic revealed that the protein digestion and absorption is the common enrichment KEGG pathway. Thus, the combination of proteomics and metabolomics opens new avenues for the research of the molecular mechanisms of tramadol toxicity.