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Mutation in CFAP43 leads to severe asthenozoospermia and multiple morphological abnormalities of the sperm flagellum (MMAF) in both human and mouse. Previous studies have shown that disruption of intra-manchette transport (IMT) caused failure of flagellum assembly and sperm head shaping. In a previous study, therefore, we postulated that disruption of IMT may contribute to the failure of sperm flagellum formation and result in MMAF, however the mechanisms underlying these defects are still poorly understood. Cfap43-deficient mice were studied here to reveal the cellular mechanisms of abnormal sperm head morphology and MMAF. Depletion of Cfap43 led to abnormal spermiogenesis and caused MMAF, sperm head abnormality and oligozoospermia. Furthermore, both abnormal manchette and disorganized ectoplasmic specialization (ES) could be observed at the elongated spermatids in Cfap43-deficient mice. Therefore, our findings demonstrated that, in mice, CFAP43-mediated IMT is essential for sperm head shaping and sperm flagellum formation.
A recently developed pneumonia caused by SARS-CoV-2 has quickly spread across the world. Unfortunately, a simplified risk score that could easily be used in primary care or general practice settings has not been developed. The objective of this study is to identify a simplified risk score that could easily be used to quickly triage severe COVID-19 patients. All severe and critical adult patients with laboratory-confirmed COVID-19 on the West campus of Union Hospital, Wuhan, China, from 28 January 2020 to 29 February 2020 were included in this study. Clinical data and laboratory results were obtained. CURB-65 pneumonia score was calculated. Univariate logistic regressions were applied to explore risk factors associated with in-hospital death. We used the receiver operating characteristic curve and multivariate COX-PH model to analyse risk factors for in-hospital death. A total of 74 patients (31 died, 43 survived) were finally included in the study. We observed that compared with survivors, non-survivors were older and illustrated higher respiratory rate, neutrophil-to-lymphocyte ratio, D-dimer and lactate dehydrogenase (LDH), but lower SpO2 as well as impaired liver function, especially synthesis function. CURB-65 showed good performance for predicting in-hospital death (area under curve 0.81, 95% confidence interval (CI) 0.71–0.91). CURB-65 ⩾ 2 may serve as a cut-off value for prediction of in-hospital death in severe patients with COVID-19 (sensitivity 68%, specificity 81%, F1 score 0.7). CURB-65 (hazard ratio (HR) 1.61; 95% CI 1.05–2.46), LDH (HR 1.003; 95% CI 1.001–1.004) and albumin (HR 0.9; 95% CI 0.81–1) were risk factors for in-hospital death in severe patients with COVID-19. Our study indicates CURB-65 may serve as a useful prognostic marker in COVID-19 patients, which could be used to quickly triage severe patients in primary care or general practice settings.
Early life stress has been associated with emotional dysregulations and altered architecture of limbic-prefrontal brain systems engaged in emotional processing. Serotonin regulates both, developmental and experience-dependent neuroplasticity in these circuits. Central serotonergic biosynthesis rates are regulated by Tryptophan hydroxylase 2 (TPH2) and transgenic animal models suggest that TPH2-gene associated differences in serotonergic signaling mediate the impact of aversive early life experiences on a phenotype characterized by anxious avoidance.
The present study employed an imaging genetics approach that capitalized on individual differences in a TPH2 polymorphism (703G/T; rs4570625) to determine whether differences in serotonergic signaling modulate the effects of early life stress on brain structure and function and punishment sensitivity in humans (n = 252).
Higher maltreatment exposure before the age of 16 was associated with increased gray matter volumes in a circuitry spanning thalamic-limbic-prefrontal regions and decreased intrinsic communication in limbic-prefrontal circuits selectively in TT carriers. In an independent replication sample, associations between higher early life stress and increased frontal volumes in TT carriers were confirmed. On the phenotype level, the genotype moderated the association between higher early life stress exposure and higher punishment sensitivity. In TT carriers, the association between higher early life stress exposure and punishment sensitivity was critically mediated by increased thalamic-limbic-prefrontal volumes.
The present findings suggest that early life stress shapes the neural organization of the limbic-prefrontal circuits in interaction with individual variations in the TPH2 gene to promote a phenotype characterized by facilitated threat avoidance, thus promoting early adaptation to an adverse environment.
This cross-sectional study aimed to examine the associations between dietary fibers (DF) intake and depressive symptoms in a general adult population in Tianjin, China. A total of 24,306 participants (mean age, 41 years; range 18-91 years) were enrolled. DF intake was assessed using a validated self-administered food frequency questionnaire. Depressive symptoms were assessed using the Self-Rating Depression Scale. Associations between DF intake and depressive symptoms were estimated using logistic regression analysis. Socio-demographic, behavioral, health status, and dietary factors were adjusted. In men, compared to participants in the lowest quartiles for total, soluble, vegetable, and soy DF, odds ratios (ORs; 95% confidence intervals [CIs]) for depressive symptoms in the highest were 0.83 (0.69, 0.99), 0.74 (0.63, 0.87), 0.79 (0.65, 0.96), and 0.69 (0.60, 0.81), respectively. In women, compared to participants in the lowest quartiles for vegetable and soy DF, the ORs (95% CIs) for depressive symptoms in the highest were 0.77 (0.64, 0.93) and 0.82 (0.70, 0.95), respectively. No association was found between total or soluble DF intake and depressive symptoms in women. No association was found between insoluble, cereal, fruit, or tuber DF intake and depressive symptoms in men and women. Linear associations between DF intake and depressive symptoms were only detected for soy foods DF (men, β = -0.148, P < 0.0001; women, β = -0.069, P = 0.04). Results suggest intake of soluble, vegetable, and soy DF were inversely associated with depressive symptoms. These results should be confirmed through prospective and interventional studies.
Fat-soluble vitamins during pregnancy are of vital importance for fetal growth and development. The present study aimed at exploring the association between vitamin A, E and D status during pregnancy and birth weight. A total of 19,640 women with singleton deliveries from a retrospective study were included. Data were collected by the hospital electronic information system. Maternal serum vitamin A, E and D concentrations were measured during pregnancy. Logistic regression was performed to estimate the association between the vitamins status and low birth weight (LBW) or macrosomia. Women with excessive vitamin E were more likely to have macrosomia (OR: 1.30, 95% CI: 1.07-1.59) compared with adequate concentration. When focusing on Z scores, there was a positive association between vitamin E and macrosomia in the 1st (OR: 1.07, 95% CI: 1.00-1.14), 2nd (OR: 1.27, 95% CI: 1.11-1.46) and 3rd (OR: 1.28, 95% CI: 1.06-1.54) trimesters; vitamin A was positively associated with LBW in the 1st (OR: 1.14, 95% CI: 1.01-1.29), 2nd (OR: 1.31, 95% CI: 1.05-1.63) and 3rd (OR: 2.00, 95% CI: 1.45-2.74) trimesters, and negatively associated with macrosomia in the 2nd (OR: 0.79, 95% CI: 0.70-0.89) and 3rd (OR: 0.77, 95% CI: 0.62-0.95) trimesters. The study identified that high concentrations of vitamin E are associated with macrosomia. Maintaining a moderate concentration of vitamin A during pregnancy might be beneficial to achieve optimal birth weight. Further studies to explore the mechanism of associations above are warranted.
No studies have reported on how to relieve distress or relax in medical health workers while wearing medical protective equipment in coronavirus disease 2019 (COVID-19) pandemic. The study aimed to establish which relaxation technique, among six, is the most feasible in first-line medical health workers wearing medical protective equipment.
This was a two-step study collecting data with online surveys. Step 1: 15 first-line medical health workers were trained to use six different relaxation techniques and reported the two most feasible techniques while wearing medical protective equipment. Step 2: the most two feasible relaxation techniques revealed by step 1 were quantitatively tested in a sample of 65 medical health workers in terms of efficacy, no space limitation, no time limitation, no body position requirement, no environment limitation to be done, easiness to learn, simplicity, convenience, practicality, and acceptance.
Kegel exercise and autogenic relaxation were the most feasible techniques according to step 1. In step 2, Kegel exercise outperformed autogenic relaxation on all the 10 dimensions among the 65 participants while wearing medical protective equipment (efficacy: 24 v. 15, no space limitation: 30 v. 4, no time limitation: 31 v. 4, no body position requirement: 26 v. 4, no environment limitation: 30 v. 11, easiness to learn: 28 v. 5, simplicity: 29 v. 7, convenience: 29 v. 4, practicality: 30 v. 14, acceptance: 32 v. 6).
Kegel exercise seems a promising self-relaxation technique for first-line medical health workers while wearing medical protective equipment among COVID-19 pandemic.
In this paper, the microstructure and the shear property of Cu/In–45Cu/Ni solder joints by transient liquid phase were studied, and the intermetallic compounds (IMCs) growth mechanism was investigated. The results showed that the IMCs volume ratio of solder joints was increased firstly and then decreased with increasing bonding time, and the IMCs volume ratio reached its maximum value of 95.8% at 60 min. The Cu interfacial IMC of the solder joint with dense microstructure was Cu2In phase at 60 min, and the Ni interfacial IMC was Ni3In7. The maximum shear strength of solder joints was obtained at 60 min, which is 15.21 MPa. The shear fracture appeared honeycomb structure, and the fracture occurred at the phase interface of Ni3In7/Cu11In9. The thickness of the interfacial IMCs and the white IMCs around the Cu particles (Cu@IMC) was increased continuously with increasing bonding time, and thus, the interconnection of Cu–Ni substrates was realized ultimately.
This Research Reflection short review presents an overview of the effects of heat stress on dairy cattle udder health and discusses existing heat stress mitigation strategies for a better understanding and identification of appropriate abatement plans for future stress management. Due to high ambient temperatures with high relative humidity in summer, dairy cows respond by changes of physical, biochemical and biological pathways to neutralize heat stress resulting in decreased production performance and poorer immunity resulting in an increased incidence of intramammary infections (IMI) and a higher somatic cell count (SCC). In vitro studies on bovine polymorphonuclear cells (PMN) suggested that heat stress reduces the phagocytosis capacity and oxidative burst of PMN and alters the expression of apoptotic genes and miRNA which, together with having a negative effect on the immune system, may explain the increased susceptibility to IMI. Although there are limited data regarding the incidence rate of clinical mastitis in many countries or regions, knowledge of SCC at the cow or bulk tank level helps encourage farmers to improve herd health and to develop strategies for infection prevention and cure. Therefore, more research into bulk tank SCC and clinical mastitis rates is needed to explain the effect of heat stress on dairy cow udder health and functions that could be influenced by abatement plans.
In the current research, a 60-day experiment was conducted with the purpose of exploring the impacts of methionine on growth performance, muscle nutritive deposition, muscle fibre growth and type I collagen synthesis as well as related signaling pathway. Six diets (iso-nitrogenous) differing in methionine concentrations (2.54, 4.85, 7.43, 10.12, 12.40 and 15.11 g kg-1 diets) were fed to 540 grass carp (178.47 ± 0.36 g). Results showed (P < 0.05) that, compared with methionine deficiency, optimal level of dietary methionine (1) increased feed intake (FI), feed efficiency (FE), specific growth rate (SGR) and percentage weight gain (PWG); (2) increased fish muscle protein, lipid and free amino acid contents, and improved fish muscle fatty acid profile as well as increased protein content in part associated with TORC1/S6K1 signaling pathway; (3) increased the frequency distribution of muscle fibre with >50 µm of diameter; (4) increased type I collagen synthesis partly related to TGF-β1/Smads and CK2/TORC1 signaling pathways. In conclusion, dietary methionine improved muscle growth, which might be due to the regulation of muscle nutritive deposition, and muscle fibre growth and type I collagen synthesis related signal molecules. Finally, according to PWG and muscle collagen content, the methionine requirements for on-growing grass carp (178-626 g) were estimated to be 9.56 g kg-1 diet (33.26 g kg-1 protein of diet) and 9.28 g kg-1 diet (32.29 g kg-1 of dietary protein), respectively.
The recent outbreak of a novel coronavirus pneumonia (COVID-19) may have acute psychological consequences, both in relation to the impact of the virus itself and the restrictions imposed to tackle its spread. We conducted an online survey of 403 residents in Guangzhou, China. We found the prevalence of anxiety (defined as Generalized Anxiety Disorder–7 score ≥5) was 37.7%, and anxiety was significantly and moderately correlated with worry about COVID-19. Higher anxiety levels in community residents was associated with the presence of individuals with COVID-19 in the same building; a longer time spent each day gathering information about the virus; and choosing social media as their preferred source of information. Our findings provide an insight into the psychological support and guidance about information sources that are required in this type of public health emergency.
The evolution of melt ponds on Arctic sea ice in summer is one of the main factors that affect sea-ice albedo and hence the polar climate system. Due to the different spectral properties of open water, melt pond and sea ice, the melt pond fraction (MPF) can be retrieved using a fully constrained least-squares algorithm, which shows a high accuracy with root mean square error ~0.06 based on the validation experiment using WorldView-2 image. In this study, the evolution of ponds on first-year and multiyear ice in the Canadian Arctic Archipelago was compared based on Sentinel-2 and Landsat 8 images. The relationships of pond coverage with air temperature and albedo were analysed. The results show that the pond coverage on first-year ice changed dramatically with seasonal maximum of 54%, whereas that on multiyear ice changed relatively flat with only 30% during the entire melting period. During the stage of pond formation, the ponds expanded rapidly when the temperature increased to over 0°C for three consecutive days. Sea-ice albedo shows a significantly negative correlation (R = −1) with the MPF in melt season and increases gradually with the refreezing of ponds and sea ice.
Corona Virus Disease 2019 (COVID-19) has presented an unprecedented challenge to the health-care system across the world. The current study aims to identify the determinants of illness severity of COVID-19 based on ordinal responses. A retrospective cohort of COVID-19 patients from four hospitals in three provinces in China was established, and 598 patients were included from 1 January to 8 March 2020, and divided into moderate, severe and critical illness group. Relative variables were retrieved from electronic medical records. The univariate and multivariate ordinal logistic regression models were fitted to identify the independent predictors of illness severity. The cohort included 400 (66.89%) moderate cases, 85 (14.21%) severe and 113 (18.90%) critical cases, of whom 79 died during hospitalisation as of 28 April. Patients in the age group of 70+ years (OR = 3.419, 95% CI: 1.596–7.323), age of 40–69 years (OR = 1.586, 95% CI: 0.824–3.053), hypertension (OR = 3.372, 95% CI: 2.185–5.202), ALT >50 μ/l (OR = 3.304, 95% CI: 2.107–5.180), cTnI >0.04 ng/ml (OR = 7.464, 95% CI: 4.292–12.980), myohaemoglobin>48.8 ng/ml (OR = 2.214, 95% CI: 1.42–3.453) had greater risk of developing worse severity of illness. The interval between illness onset and diagnosis (OR = 1.056, 95% CI: 1.012–1.101) and interval between illness onset and admission (OR = 1.048, 95% CI: 1.009–1.087) were independent significant predictors of illness severity. Patients of critical illness suffered from inferior survival, as compared with patients in the severe group (HR = 14.309, 95% CI: 5.585–36.659) and in the moderate group (HR = 41.021, 95% CI: 17.588–95.678). Our findings highlight that the identified determinants may help to predict the risk of developing more severe illness among COVID-19 patients and contribute to optimising arrangement of health resources.
Double-layer absorbers have recently been extensively studied because single-layer absorbers can hardly meet the requirements of advanced absorbing materials. However, determining how to couple the matching and absorption layers remains a challenge. In the present work, we applied the hydrothermal method to prepare an ultrasmall Fe3O4 nanoparticle and a hierarchical MXene/Fe3O4 composite and then studied the microwave attenuation capabilities of single- and double-layer absorbers containing these two materials with different thicknesses. Absorbers with well-coupled layers showed improved absorption performance on account of the excellent impedance matching behavior of the Fe3O4 layer and the high microwave attenuation capability of the MXene/Fe3O4 layer. When the thickness of the matching layer filled with Fe3O4 was 0.1 mm and that of the absorption layer filled with MXene/Fe3O4 was 1.9 mm, a maximum reflection loss of −48.7 dB was achieved at 9.9 GHz. More importantly, when the thicknesses of the matching and absorption layers were 0.9 and 1.1 mm, respectively, the effective bandwidth was nearly 3.9 GHz. The double-layer absorbers with enhanced absorption properties may be regarded as a new generation of materials for electromagnetic wave absorption.
In this paper, the generation of relativistic electron mirrors (REM) and the reflection of an ultra-short laser off the mirrors are discussed, applying two-dimension particle-in-cell simulations. REMs with ultra-high acceleration and expanding velocity can be produced from a solid nanofoil illuminated normally by an ultra-intense femtosecond laser pulse with a sharp rising edge. Chirped attosecond pulse can be produced through the reflection of a counter-propagating probe laser off the accelerating REM. In the electron moving frame, the plasma frequency of the REM keeps decreasing due to its rapid expansion. The laser frequency, on the contrary, keeps increasing due to the acceleration of REM and the relativistic Doppler shift from the lab frame to the electron moving frame. Within an ultra-short time interval, the two frequencies will be equal in the electron moving frame, which leads to the resonance between laser and REM. The reflected radiation near this interval and corresponding spectra will be amplified due to the resonance. Through adjusting the arriving time of the probe laser, a certain part of the reflected field could be selectively amplified or depressed, leading to the selective adjustment of the corresponding spectra.
The first case of 2019-nCoV pneumonia infection occurred in Wuhan, Hubei Province, South China Seafood Market in December 2019. As a group with a high probability of infection, health workers are faced with a certain degree of psychological challenges in the process of facing the epidemic. This study attempts to evaluate the impact of 2019-nCoV outbreak on the psychological state of Chinese health workers and to explore the influencing factors. During the period from 31 January 2020 to 4 February 2020, the ‘Questionnaire Star’ electronic questionnaire system was used to collect data. The 2019-nCoV impact questionnaire and The Impact of Event Scale (IES) were used to check the psychological status of health workers in China. A total of 442 valid data were collected in this study. Seventy-four (16.7%) male and 368 (83.3%) female individuals participated in this study. The average score of high arousal dimension was 5.15 (s.d. = 4.71), and the median score was 4.0 (IQR 2.0, 7.0). The average score of IES was 15.26 (s.d. = 11.23), and the median score was 13.5 (IQR 7.0, 21.0). Multiple regression analysis showed that there were critical statistical differences in high arousal scores among different gender groups (male 3.0 vs. female 5.0, P = 0.075). Whether being quarantined had significant statistical differences of IES scores (being quarantined 16.0 vs. not being quarantined 13.0, P = 0.021). The overall impact of the 2019-nCoV outbreak on health workers is at a mild level. Chinese health workers have good psychological coping ability in the face of public health emergencies.