The COVID-19 pandemic has had a profound impact on the mental health of healthcare workers (HCWs). We aimed to identify the factors associated with depression among HCWs during the pandemic. We conducted literature search using eight electronic databases up to July 27 2022. Observational studies with more than 200 participants investigating correlates of depression in HCWs after COVID-19 outbreak were included. We used fixed- and random-effects models to pool odds ratios (ORs) across studies, and Cochran's chi-squared test and I2 statistics to assess study heterogeneity. Publication bias was evaluated by funnel plots. Thirty-five studies involving 44,362 HCWs met the inclusion criteria. Female (OR=1.50, 95% CI [1.23,1.84]), single (OR=1.36, 95% CI [1.21,1.54]), nurse (OR=1.69, 95% CI [1.28,2.25]), history of mental diseases (OR=2.53, 95% CI [1.78,3.58]), frontline (OR=1.79, 95% CI [1.38,2.32]), health anxiety due to COVID-19 (OR=1.88, 95% CI [1.29,2.76]), working in isolation wards (OR=1.98, 95% CI [1.38,2.84]), and insufficient personal protective equipment (OR=1.49, 95% CI [1.33,1.67]) were associated with increased risk of depression. Instead, HCWs with a positive professional prospect (OR=0.34, 95% CI [0.24,0.49]) were less likely to be depressed. This meta-analysis provides up-to-date evidence on the factors linked to depression among HCWs during the COVID-19 pandemic. Given the persistent threats posed by COVID-19, early screening is crucial for the intervention and prevention of depression in HCWs.

Sterol regulatory element-binding protein 2 (SREBP2) is considered to be a major regulator to control cholesterol homeostasis in mammals. However, the role of SREBP2 in teleost remains poorly understand. Here, we explored the molecular characterization of SREBP2 and identified SREBP2 as a key modulator for 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) and 7-dehydrocholesterol reductase (DHCR7) which were rate-limiting enzymes of cholesterol biosynthesis. Moreover, dietary palm oil (PO) in vivo or palmitic acid (PA) treatment in vitro elevated cholesterol content through triggering SREBP2-mediated cholesterol biosynthesis in large yellow croaker. Furthermore, our results also found that PA-induced activation of SREBP2 was dependent on the stimulating of endoplasmic reticulum stress (ERS) in croaker myocytes and inhibition of ERS by 4-Phenylbutyric acid alleviated PA-induced SREBP2 activation and cholesterol biosynthesis. In summary, our findings reveal a novel insight for understanding the role of SREBP2 in regulation of cholesterol metabolism in fish and may deepen the link between dietary fatty acid and cholesterol biosynthesis.

Compared with nitrogen and argon, helium is lighter and can better reduce the beam loss caused by angular scattering during beam transmission. The molecular dissociation cross-section in helium is high and stable at low energies, which makes helium the prevalent stripping gas in low-energy accelerator mass spectrometry (AMS). To study the stripping behavior of 14C ions in helium at low energies, the charge state distributions of carbon ion beams with −1, +1, +2, +3, and +4 charge states were measured at energies of 70–220 keV with a compact 14C-AMS at Guangxi Normal University (GXNU). The experimental data were used to analyze the stripping characteristics of C-He in the energy range of 70–220 keV, and new charge state yields and exchange cross-sections in C-He were obtained at energies of 70–220 keV.

Childhood maltreatment exerts long-term consequences on sleep health, and different subtypes could constitute maltreatment patterns. However, how naturally occurring patterns of childhood maltreatment affect subsequent sleep quality and the underlying mechanisms remain relatively unclear, particularly in youths undergoing a transitional period and in the Chinese cultural context. In this study, we identified childhood maltreatment patterns and explored how these patterns predicted sleep problems through differential emotion regulation strategies. We tracked 1929 Chinese youths (M age = 18.49; 63.1% females) for one year. Three latent profiles were identified: low maltreatment exposure, high physical and emotional maltreatment, and high sexual abuse. Compared with “low maltreatment exposure,” youths in “high physical and emotional maltreatment” used fewer cognitive reappraisal strategies, and those in “high sexual abuse” used more expressive suppression, and then leading to more sleep problems. This study reveals new insights into the patterns of childhood maltreatment in Chinese youths and implies that individuals exposed to sexual abuse or a combination of physical and emotional maltreatment experience sleep problems through the impairment of differential emotion regulation processes. It also highlights the necessity of setting differential targets on emotion regulation strategies for distinct groups of maltreatment and considering the co-occurrence of physical and emotional maltreatment.

A single-stage accelerator mass spectrometer (GXNU-AMS) developed for radiocarbon and tritium measurements was installed and commissioned at Guangxi Normal University in 2017. After several years of operational and methodological upgrades, its performance has been continuously improved and applied in multidisciplinary fields. Currently, the measurement sensitivity for radiocarbon and tritium is 14C/12C ∼ (3.14 ± 0.05) ×10–15 and 3H/1H ∼ (1.23 ± 0.17)×10–16, respectively, and the measurement accuracy is ∼0.6%, which can meet the measurement requirements in the nuclear, earth, environmental and life science fields. This study presents the performance characteristics of GXNU-AMS and several interesting application studies.

A high image rejection 38 GHz demodulator in TSMC 65-nm CMOS process is presented. To achieve better than −40 dBc image rejection ratio (IRR), a low I/Q mismatch 45° LO power splitter of sub-harmonic mixer is proposed. In this design, the 45° LO power splitter is composed of a Wilkinson divider, a series delay line with electrical length of 45° on one side of the divider, and a shunt 90° transmission line on the other side. This configuration is attractive because of its design simplicity and easy fabrication. Compared with the conventional techniques that utilize capacitors and inductors instead of the shunt 90° transmission line, the proposed LO power splitter can alleviate the issue of process variation. The demodulator demonstrates an IRR lower than −40 dBc from 37.5 to 41.5 GHz. In addition, conversion gain is 1.3 ± 0.9 dB from 33 to 41 GHz with 6 dBm LO power. The total direct current power consumption is 78 mW from 1.0 V supply voltage. At the modulation scheme of 4096-QAM, the proposed demodulator demonstrates 1.7% (−35.1 dB) error vector magnitude (EVM), which is very close to the EVM measurement floor 1.6% (−36 dB) of our millimeter-wave signal analyzer.

Fat deposition and lipid metabolism are closely related to the morphology, structure and function of mitochondria. The morphology of mitochondria between fusion and fission processes is mainly regulated by protein posttranslational modification. Intermittent fasting (IF) promotes high expression of Sirtuin 3 (Sirt3) and induces mitochondrial fusion in high-fat diet (HFD)-fed mice. However, the mechanism by which Sirt3 participates in mitochondrial protein acetylation during IF to regulate mitochondrial fusion and fission dynamics remains unclear. This article demonstrates that IF promotes mitochondrial fusion and improves mitochondrial function in HFD mouse inguinal white adipose tissue. Proteomic sequencing revealed that IF increased protein deacetylation levels in HFD mice and significantly increased Sirt3 mRNA and protein expression. After transfecting with Sirt3 overexpression or interference vectors into adipocytes, we found that Sirt3 promoted adipocyte mitochondrial fusion and improved mitochondrial function. Furthermore, Sirt3 regulates the JNK-FIS1 pathway by deacetylating malate dehydrogenase 2 (MDH2) to promote mitochondrial fusion. In summary, our study indicates that IF promotes mitochondrial fusion and improves mitochondrial function by upregulating the high expression of Sirt3 in HFD mice, promoting deacetylation of MDH2 and inhibiting the JNK-FIS1 pathway. This research provides theoretical support for studies related to energy limitation and animal lipid metabolism.

The aeroacoustic characteristics of flying vehicles with pitch-fixed rotors differ from traditional helicopters with pitch-controlled rotor blades. Accurate predictions of rotor noise are still challenging because many uncertainty factors and unsteadinesses exist. This work investigates the aeroacoustic effects of rotational speed deviation, rotation speed fluctuation, blade vibration and blade geometric asymmetry. The analysis is based on the efficient computation of rotor noise under different working conditions. The mean aerodynamic variables are computed using the blade element moment theory, while small-amplitude fluctuations are introduced to account for the unsteadiness and uncertainty factors. It is shown that periodic rotation speed fluctuations and blade vibrations can produce significant extra tones. By contrast, if the fluctuations and vibrations are random, the noise level in a wide frequency range is increased. The intriguing result reminds us of the need to revisit the rotor broadband noise sources commonly attributed to turbulent flows. The influences are observer angle dependent, and the extra noise production is more significant in the upstream and downstream directions. The asymmetric blade geometry can cause extra tonal noise at the harmonics of the blade shaft frequency. The noise features of dual rotors are also investigated. Usually, the noise is sensitive to the initial phase difference and rotation directions due to the interference effect. However, the noise features are vastly altered if there are slight differences in the rotation speeds. Although the influences of some factors on rotor noise were already known, the present study provides a more comprehensive analysis of the problem. The results also highlight the need to consider these practical factors for accurate noise prediction of multi-rotor flying vehicles.

Few studies examined the association of energy, macronutrients and food consumption at dinner v. breakfast with hypercholesterolaemia. A total of 27 911 participants from the National Health and Nutrition Examination Survey (2003–2016) were included in the cross-sectional study. Energy, macronutrients and food consumption at breakfast, dinner and the difference at dinner v. breakfast (Δratio) were calculated. Multiple logistic regression models and substitution effects of foods at dinner with breakfast were also performed. After adjustment for potential covariates, compared with the lowest quintile, participants in the highest quintile of Δratio in terms of energy had a higher risk of prevalent hypercholesterolaemia (ORΔratio of energy 1·16, 95 % CI (1·01, 1·33)) mainly due to Δratio of low-quality carbohydrates and plant protein (ORΔratio of low-quality carbohydrates 1·19; 95 % CI (1·05, 1·35)); ORΔratio of plant protein 1·13; 95 % CI (1·01, 1·28)). ΔAdded sugars and Δnuts were associated with hypercholesterolaemia (ORΔadded sugars 1·01; 95 % CI (1·00, 1·02)); ORΔnuts 1·08; 95 % CI (1·01, 1·16)). Furthermore, the substitution of added sugars, nuts and processed meat at dinner with breakfast could reduce the OR of hypercholesterolaemia. This study indicated that among US adults, overconsumption of energy, macronutrients including low-quality carbohydrates and plant protein at dinner than breakfast was significantly associated with a higher risk of prevalent hypercholesterolaemia. The replacing of added sugar, nuts and processed meat at dinner with breakfast reduced the risk of prevalent hypercholesterolaemia. This study emphasised the importance of meal timing in the prevention of hypercholesterolaemia.

Se is an essential trace element associated with animal growth and antioxidant and metabolic processes. However, whether Se, especially organic Se with higher bioavailability, can alleviate the adverse effects of low salinity stress on marine economic crustacean species has not been investigated. Accordingly, juvenile Pacific white shrimp (Litopenaeus vannamei) were reared in two culture conditions (low and standard salinity) fed diets supplemented with increasing levels of l-selenomethionine (0·41, 0·84 and 1·14 mg/kg Se) for 56 d, resulting in four treatments: 0·41 mg/kg under standard seawater (salinity 31) and 0·41, 0·84 and 1·14 mg/kg Se under low salinity (salinity 3). The diet containing 0·84 mg/kg Se significantly improved the survival and weight gain of shrimp under low salinity stress and enhanced the antioxidant capacity of the hepatopancreas. The increased numbers of B and R cells may be a passive change in hepatopancreas histology in the 1·14 mg/kg Se group. Transcriptomic analysis found that l-selenomethionine was involved in the regulatory pathways of energy metabolism, retinol metabolism and steroid hormones. In conclusion, dietary supplementation with 0·84 mg/kg Se (twice the recommended level) effectively alleviated the effects of low salinity stress on L. vannamei by regulating antioxidant capacity, hormone regulation and energy metabolism.

The North China Plain is an important summer maize/winter wheat rotation area. However, over the years, continued intensive tillage has destroyed the soil aggregate accelerating the mineralization and decomposition of soil organic carbon (SOC), which plays an important role in soil quality, as increased organic carbon storage improves soil fertility and crop yields. Thus, the objective of this study was to explore the comprehensive impact of tillage methods on soil aggregates, aggregate-associated SOC, and carbon sequestration capacity under a regime of straw return. In 2002, we started a 14-year long-term tillage experiment; then in 2016–2017, we tested the following tillage methods, zero tillage (ZT), rotary tillage (RT), subsoiling (SS), and conventional tillage (CT). The results showed that in the 0–10 cm soil layer, tillage methods significantly reduced the proportion of aggregates in the order of 2–0.25 > 5–2 > 0.25–0.053 mm. Additionally, conservation tillage (i.e., SS and ZT) significantly increased the percentage of macroaggregates (0–40 cm) and their SOC content, compared to CT. Additionally, the contribution rate of macroaggregates to SOC was 17.2% and 30.6% higher under SS and ZT than under CT, respectively. Conservation tillage methods improved the carbon sequestration capacity of soil aggregates. Our study provides a theoretical basis for the development of more suitable tillage methods. Furthermore, long-term conservation tillage seemingly protected large aggregates and, SOC, whereby carbon sequestration was enhanced and soil carbon emissions were effectively reduced.

In this paper, a compact four-element quasi-self-complementary (QSC) ultra-wideband (UWB) multiple-input multiple-output antenna with triple band-notched characteristics is proposed. Coplanar waveguides fed QSC structure is designed as radiation element to achieve wideband and small size. Besides, regular hexagonal split-ring resonators with single negative properties are designed and added on the back of the substrate to obtain high isolation in the whole operating band. Moreover, a double-fork-shaped slit is etched in each radiating element to generate three notched bands covering 3.63–4.24, 5.15–5.98, and 7.17–8 GHz. The experiment results indicate that the isolation of the proposed antenna is higher than 22 dB and the peak gain varies from 2.5 to 6.7 dB in the entire band of 3–18 GHz, which demonstrates that it is suitable for UWB applications.

Biped robots with dynamic motion control have shown strong robustness in complex environments. However, many motion planning methods rely on models, which have difficulty dynamically modifying the walking cycle, height, and other gait parameters to cope with environmental changes. In this study, a heuristic model-free gait template planning method with dynamic motion control is proposed. The gait trajectory can be generated by inputting the desired speed, walking cycle, and support height without a model. Then, the stable walking of the biped robot can be realized by foothold adjustment and whole-body dynamics model control. The gait template can be changed in real time to achieve gait flexibility of the biped robot. Finally, the effectiveness of the method is verified by simulations and experiments of the biped robot BHR-B2. The research presented here helps improve the gait transition ability of biped robots in dynamic locomotion.