Ion and water are transported by electroconvection near permselective membranes, resulting in complex phenomena associated with the flow–fines interaction. Sheltering the flow chaos by the shear flow is a common strategy in plasma fluids and has recently been successfully applied to control ionic fluids. The paper herein reveals the critical selection of shear velocity regarding the fluid from a chaotic to a steady state through numerical and theoretical analyses. For the shear sheltering, the dimensionless Debye length ${\lambda _D}$ with varying channel height is introduced to achieve a comprehensive discussion of the factors and laws affecting the shear vortex state. Based on an analysis of the vortex driving mechanism, the scaling of the slip velocity ${u_s}\sim {(\lambda _D^{ - 1}\Delta {\phi ^4})^{1/3}}$ is recommended as the critical selection factor for the steady and chaotic state under a fixed shear flow velocity, which involves the dimensionless Debye length ${\lambda _D}$ and voltage difference $\Delta \phi $. Furthermore, for ionic fluid control by shear flow, a critical shear velocity ${U_{HPC}}$ is proposed to distinguish the electroconvective flow from a chaotic state to a steady state. When the shear flow velocity ${U_{HP}} > {U_{HPC}}$, the shear flow shelters chaos, and the scaling law is also recommended for the regulation of the critical shear flow velocity ${U_{HPC}}$ jointly by ${\lambda _D}$ and $\Delta \phi $. The analysis is confirmed by direct numerical simulation and existing experimental data (J. Fluid Mech, vol. 813, 2017, pp. 799–823). This work provides a more comprehensive physical insight for shear sheltering and affects the design of electromembrane microfluidics.

The selection of high-quality sperms is critical to intracytoplasmic sperm injection, which accounts for 70–80% of in vitro fertilization (IVF) treatments. So far, sperm screening is usually performed manually by clinicians. However, the performance of manual screening is limited in its objectivity, consistency, and efficiency. To overcome these limitations, we have developed a fast and noninvasive three-stage method to characterize morphology of freely swimming human sperms in bright-field microscopy images using deep learning models. Specifically, we use an object detection model to identify sperm heads, a classification model to select in-focus images, and a segmentation model to extract geometry of sperm heads and vacuoles. The models achieve an F1-score of 0.951 in sperm head detection, a z-position estimation error within ±1.5 μm in in-focus image selection, and a Dice score of 0.948 in sperm head segmentation, respectively. Customized lightweight architectures are used for the models to achieve real-time analysis of 200 frames per second. Comprehensive morphological parameters are calculated from sperm head geometry extracted by image segmentation. Overall, our method provides a reliable and efficient tool to assist clinicians in selecting high-quality sperms for successful IVF. It also demonstrates the effectiveness of deep learning in real-time analysis of live bright-field microscopy images.

A new system for preparing 14C samples was established for a compact accelerator mass spectrometer (GXNU-AMS) at Guangxi Normal University. This sample preparation system consists of three units: a vacuum maintenance unit, a CO2 purification unit, and a CO2 reduction unit, all of which were made of quartz glass. A series of radiocarbon (14C) preparation experiments were conducted to verify the reliability of the system. The recovery rate of graphite obtained was more than 80%. The carbon content in the commercial toner and wood sample was linearly fitted to the CO2 pressure in the measurement unit of the system. The results showed a good linear relationship, indicating that the reliability of the sample preparation system. AMS measurements were conducted on a batch of standard, wood, and dead graphite samples prepared using this system. The results showed that the beam current of 12C- for each sample was more than 40 μA, the carbon contamination introduced during the sample preparation process was ∼ 2 × 10–15, and that the new sample preparation system is compact, low-contamination, and efficient and meets the GXNU-AMS requirements for 14C samples.

Many waterflooding oil fields, injecting water into an oil-bearing reservoir for pressure maintenance, are in their middle to late stages of development. To explore the geological conditions and improve oilfield recovery of the most important well group of the Hu 136 block, located on the border areas of three provinces (Henan, Shandong, and Hebei), Zhongyuan Oilfield, Sinopec, central China, a 14C cross-well tracer monitoring technology was developed and applied in monitoring the development status and recognize the heterogeneity of oil reservoirs. The tracer response in the production well was tracked, and the water drive speed, swept volume of the injection fluid were obtained. Finally, the reservoir heterogeneity characteristics, such as the dilution coefficient, porosity, permeability, and average pore-throat radius, were fitted according to the mathematical model of the heterogeneous multi-layer inter-well theory. The 14C-AMS technique developed in this work is expected to be a potential analytical method for evaluating underground reservoir characteristics and providing crucial scientific guidance for the mid to late oil field recovery process.

In this paper, we present explicit and computable error bounds for the asymptotic expansions of the Hermite polynomials with Plancherel–Rotach scale. Three cases, depending on whether the scaled variable lies in the outer or oscillatory interval, or it is the turning point, are considered separately. We introduce the ‘branch cut’ technique to express the error terms as integrals on the contour taken as the one-sided limit of curves approaching the branch cut. This new technique enables us to derive simple error bounds in terms of elementary functions. We also provide recursive procedures for the computation of the coefficients appearing in the asymptotic expansions.

This study examines family context and sexual debut among young people in China. Using data from the 2018 Panel Study of Chinese University Students (PSCUS), it explores how the family is correlated with sexual debut among young people in China aged 18–24 years. The Kaplan–Meier method was adopted to detect a survival function for different family factors and related demographic variables. Cox proportional hazard regression analysis was adopted to calculate hazard ratios for the timing of sexual debut. The average age of sexual debut among the college students was 18.39 years. The Kaplan–Meier analysis showed that sexual intercourse initiation was earlier for female students who had no siblings, and those who had a mother with senior high school (including technical school) education or higher family income, but this correlation was insignificant among male students. The multivariate hazard regression analysis revealed that living in a family with a higher level of fathers’ education, having a lower level of family income and having siblings had positive correlations with later sexual debut among the college students. Moreover, family factors showed gender differences in their associations with the timing of sexual debut, typically parent’s education level, family income and left-behind experience. This study provides a comprehensive perspective on the role of family influences in timing of sexual debut among youth in China.

No relevant studies have yet been conducted to explore which measurement can best predict the survival time of patients with cancer cachexia. This study aimed to identify an anthropometric measurement that could predict the 1-year survival of patients with cancer cachexia. We conducted a nested case–control study using data from a multicentre clinical investigation of cancer from 2013 to 2020. Cachexia was defined using the Fearon criteria. A total of 262 patients who survived less than 1 year and 262 patients who survived more than 1 year were included in this study. Six candidate variables were selected based on clinical experience and previous studies. Five variables, BMI, mid-arm circumference, mid-arm muscle circumference, calf circumference and triceps skin fold (TSF), were selected for inclusion in the multivariable model. In the conditional logistic regression analysis, TSF (P = 0·014) was identified as a significant independent protective factor. A similar result was observed in all patients with cancer cachexia (n 3084). In addition, a significantly stronger positive association between TSF and the 1-year survival of patients with cancer cachexia was observed in participants aged > 65 years (OR: 0·94; 95 % CI 0·89, 0·99) than in those aged ≤ 65 years (OR: 0·96; 95 % CI 0·93, 0·99; Pinteraction = 0·013) and in participants with no chronic disease (OR: 0·92; 95 % CI 0·87, 0·97) than in those with chronic disease (OR: 0·97; 95 % CI 0·94, 1·00; Pinteraction = 0·049). According to this study, TSF might be a good anthropometric measurement for predicting 1-year survival in patients with cancer cachexia.

By integrating role theory and social identity theory, this study examines the differential effects of organizational identification of the chief executive officer (CEO) and the chief financial officer (CFO) on corporate philanthropy. We argue that CEO organizational identification can positively affect corporate philanthropy, whereas the opposite holds for CFO organizational identification. This is because the CEO and the CFO have varying attitudes about corporate philanthropy owing to their different role expectations; thus, those who identify strongly with their organizations would act for the best interests of the firm. Moreover, because the beliefs of top executives are probably influenced by those of other executives, we further explore the interaction between the CEO and the CFO. We propose that the positive influence of CEO organizational identification on corporate philanthropy will be weakened by CFO organizational identification, and the moderating effect of CFO organizational identification will become stronger when the CEO and the CFO have opposite genders or when the CFO has ownership. From a sample of 880 publicly traded firms in China, we found support for our hypotheses. Our study can contribute to the corporate philanthropy literature and research on executive organizational identification by highlighting the importance of executive roles and their interactions.

The present study evaluated whether fat mass assessment using the triceps skinfold (TSF) thickness provides additional prognostic value to the Global Leadership Initiative on Malnutrition (GLIM) framework in patients with lung cancer (LC). We performed an observational cohort study including 2672 LC patients in China. Comprehensive demographic, disease and nutritional characteristics were collected. Malnutrition was retrospectively defined using the GLIM criteria, and optimal stratification was used to determine the best thresholds for the TSF. The associations of malnutrition and TSF categories with survival were estimated independently and jointly by calculating multivariable-adjusted hazard ratios (HR). Malnutrition was identified in 808 (30·2 %) patients, and the best TSF thresholds were 9·5 mm in men and 12 mm in women. Accordingly, 496 (18·6 %) patients were identified as having a low TSF. Patients with concurrent malnutrition and a low TSF had a 54 % (HR = 1·54, 95 % CI = 1·25, 1·88) greater death hazard compared with well-nourished individuals, which was also greater compared with malnourished patients with a normal TSF (HR = 1·23, 95 % CI = 1·06, 1·43) or malnourished patients without TSF assessment (HR = 1·31, 95 % CI = 1·14, 1·50). These associations were concentrated among those patients with adequate muscle mass (as indicated by the calf circumference). Additional fat mass assessment using the TSF enhances the prognostic value of the GLIM criteria. Using the population-derived thresholds for the TSF may provide significant prognostic value when used in combination with the GLIM criteria to guide strategies to optimise the long-term outcomes in patients with LC.

We report a direct numerical simulation (DNS) study of the mean velocity and temperature profiles in turbulent Rayleigh–Bénard convection (RBC) at low Prandtl numbers ($Pr$). The numerical study is conducted in a vertical thin disk with $Pr$ varied in the range $0.17\leq Pr\leq 4.4$ and the Rayleigh number ($Ra$) varied in the range $5\times 10^8\leq Ra \leq 1\times 10^{10}$. By varying $Pr$ from 4.4 to 0.17, we find a sharp change of flow patterns for the large-scale circulation (LSC) from a rigid-body rotation to a near-wall turbulent jet. We numerically examine the mean velocity equation in the bulk region and find that the mean horizontal velocity profile $u(z)$ can be determined by a balance equation between the mean convection and turbulent diffusion with a constant turbulent viscosity $\nu _t$. This balance equation admits a self-similarity jet solution, which fits the DNS data well. In the boundary-layer region, we find that both the mean temperature profile $T(z)$ and $u(z)$ can be determined by a balance equation between the molecular diffusion and turbulent diffusion. Within the viscous boundary layer, both $u(z)$ and $T(z)$ can be solved analytically and the analytical results agree well with the DNS data. Our careful characterisation of the mean velocity and temperature profiles in low-$Pr$ RBC provides a further understanding of the intricate interplay between the LSC, plume emission and boundary-layer dynamics, and pinpoints the physical mechanism for the emergence of a pronounced LSC in low-$Pr$ RBC.

This experiment was designed to investigate the effect of supplementing conjugated linoleic acid (CLA) in breeder hens diet on development and hepatic lipid metabolism of chick offspring. Hy-Line Brown breeder hens were allocated into two groups, supplemented with 0 (control (CT)) or 0·5 % CLA for 8 weeks. Offspring chicks were grouped according to the mother generation and fed for 7 d. CLA treatment had no significant influence on development, egg quality and fertility of breeder hens but darkened the egg yolks in shade and increased yolk sac mass compared with the CT group. Addition of CLA resulted in increased body mass and liver mass and decreased deposition of subcutaneous adipose tissue in chick offspring. The serum TAG and total cholesterol levels of chick offspring were decreased in CLA group. CLA treatment increased the incorporation of both CLA isomers (c9t11 and t10c12) in the liver of chick offspring, accompanied by the decreased hepatic TAG levels, related to the significant reduction of fatty acid synthase (FAS) and acetyl-CoA carboxylase (ACC) enzyme activities and the increased carnitine palmitoyltransferase-1 (CPT1) enzyme activity. Meanwhile, CLA treatment reduced the mRNA expression of genes related to fatty acid biosynthesis (FAS, ACC and sterol regulatory element-binding protein-1c) and induced the expression of genes related to β-oxidative (CPT1, AMP-activated protein kinase and PPARα) in chick offspring liver. In summary, the addition of CLA in breeder hens diet significantly increased the incorporation of CLA in the liver of chick offspring, which further regulate hepatic lipid metabolism.

Tuberculosis (TB) remains a global public health threat. Misdiagnosis and delayed therapy of sputum smear-negative TB can affect the treatment outcomes and promote pathogen transmission. The application of Xpert MTB/RIF assay in bronchoalveolar lavage fluid (BALF) has been recommended but needs clinical evidence. We carried out a prospective study in the Nanjing Public Health Medical Center from September 2018 to August 2019. Pulmonary tuberculosis (PTB) patients were enrolled in the study if they had negative results of sputum smear. We compared the performance of Xpert MTB/RIF assay in sputum and BALF using sputum culture as the reference. In addition to this, we applied parallel tests using sputum culture, sputum-based Xpert MTB/RIF assay and BALF-based Xpert MTB/RIF assay to jointly detect smear-negative PTB using clinical diagnosis as the reference. With mycobacterial culture as the reference standard, Xpert MTB/RIF of BALF showed a higher sensitivity (14/16, 87.5%), but a relatively lower specificity (57/92, 62.0%). Xpert MTB/RIF of sputum showed relatively lower sensitivity (6/10, 60.0%) and higher specificity (63/88, 71.6%). Compared with sputum culture, Xpert MTB /RIF assay reduced the median detection time of MTB from 30 to 0 days, which significantly shortened the diagnosis time of the smear-negative TB patients. Among the combined detections, the positive detection proportion was improved with significant differences comparing with sputum culture only, from 11.1% (10/90) to 46.7% (42/90) (P < 0.05). Our study showed Xpert MTB/RIF in BALF had a better performance in detecting MTB of smear-negative patients.

The upsurge in the number of people affected by the COVID-19 is likely to lead to increased rates of emotional trauma and mental illnesses. This article systematically reviewed the available data on the benefits of interventions to reduce adverse mental health sequelae of infectious disease outbreaks, and to offer guidance for mental health service responses to infectious disease pandemic. PubMed, Web of Science, Embase, PsycINFO, WHO Global Research Database on infectious disease, and the preprint server medRxiv were searched. Of 4278 reports identified, 32 were included in this review. Most articles of psychological interventions were implemented to address the impact of COVID-19 pandemic, followed by Ebola, SARS, and MERS for multiple vulnerable populations. Increasing mental health literacy of the public is vital to prevent the mental health crisis under the COVID-19 pandemic. Group-based cognitive behavioral therapy, psychological first aid, community-based psychosocial arts program, and other culturally adapted interventions were reported as being effective against the mental health impacts of COVID-19, Ebola, and SARS. Culturally-adapted, cost-effective, and accessible strategies integrated into the public health emergency response and established medical systems at the local and national levels are likely to be an effective option to enhance mental health response capacity for the current and for future infectious disease outbreaks. Tele-mental healthcare services were key central components of stepped care for both infectious disease outbreak management and routine support; however, the usefulness and limitations of remote health delivery should also be recognized.