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The clinical characteristics of patients with COVID-19 were analysed to determine the factors influencing the prognosis and virus shedding time to facilitate early detection of disease progression. Logistic regression analysis was used to explore the relationships among prognosis, clinical characteristics and laboratory indexes. The predictive value of this model was assessed with receiver operating characteristic curve analysis, calibration and internal validation. The viral shedding duration was calculated using the Kaplan–Meier method, and the prognostic factors were analysed by univariate log-rank analysis and the Cox proportional hazards model. A retrospective study was carried out with patients with COVID-19 in Tianjin, China. A total of 185 patients were included, 27 (14.59%) of whom were severely ill at the time of discharge and three (1.6%) of whom died. Our findings demonstrate that patients with an advanced age, diabetes, a low PaO2/FiO2 value and delayed treatment should be carefully monitored for disease progression to reduce the incidence of severe disease. Hypoproteinaemia and the fever duration warrant special attention. Timely interventions in symptomatic patients and a time from symptom onset to treatment <4 days can shorten the duration of viral shedding.
The Wulian complex is located on the northern margin of the Sulu orogenic belt, and was formed by collision between the North China Craton (NCC) to the north and South China Craton (SCC) to the south. It consists of the metasedimentary Wulian Group, gneissic granite and meta-diorite. The U–Pb analyses for the detrital zircons from the Wulian Group exhibit one predominant age population of 2600–2400 Ma with a peak at c. 2.5 Ga and several secondary age populations of > 3000, 3000–2800, 2800–2600, 2200–2000, 1900–1800, 1500–1300 and 1250–950 Ma; some metamorphic zircons have metamorphic ages of c. 2.7, 2.55–2.45, 2.1–2.0 and 1.95–1.80 Ga, which are consistent with magmatic-metamorphic events in the SCC. Additionally, the Wulian Group was intruded by the gneissic granite and meta-diorite at c. 0.76 Ga, attributed to Neoproterozoic syn-rifting bimodal magmatic activity in the SCC and derived from partial melting of Archaean continental crust and depleted mantle, respectively. The Wulian Group therefore has tectonic affinity to the SCC and was mainly sourced from the SCC. The detrital zircons have positive and negative ϵHf(t) values, indicating that their source rocks were derived from reworking of both ancient and juvenile crustal rocks. The major early Precambrian crustal growth took place during c. 3.4–2.5 Ga with a dominant peak at 2.96 Ga and several secondary peaks at 3.27, 2.74 and 2.52 Ga. The two oldest zircons with ages of 3307 and 3347 Ma record the recycling of ancient continental crust (> 3.35 Ga) and crustal growth prior to c. 3.95 Ga in the SCC.
In late December 2019, patients of atypical pneumonia due to an unidentified microbial agent were reported in Wuhan, Hubei Province, China. Subsequently, a novel coronavirus was identified as the causative pathogen which was named SARS-CoV-2. As of 12 February 2020, more than 44 000 cases of SARS-CoV-2 infection have been confirmed in China and continue to expand. Provinces, municipalities and autonomous regions of China have launched first-level response to major public health emergencies one after another from 23 January 2020, which means restricting movement of people among provinces, municipalities and autonomous regions. The aim of this study was to explore the correlation between the migration scale index and the number of confirmed coronavirus disease 2019 (COVID-19) cases and to depict the effect of restricting population movement. In this study, Excel 2010 was used to demonstrate the temporal distribution at the day level and SPSS 23.0 was used to analyse the correlation between the migration scale index and the number of confirmed COVID-19 cases. We found that since 23 January 2020, Wuhan migration scale index has dropped significantly and since 26 January 2020, Hubei province migration scale index has dropped significantly. New confirmed COVID-19 cases per day in China except for Wuhan gradually increased since 24 January 2020, and showed a downward trend from 6 February 2020. New confirmed COVID-19 cases per day in China except for Hubei province gradually increased since 24 January 2020, and maintained at a high level from 24 January 2020 to 4 February 2020, then showed a downward trend. Wuhan migration scale index from 9 January to 22 January, 10 January to 23 January and 11 January to 24 January was correlated with the number of new confirmed COVID-19 cases per day in China except for Wuhan from 22 January to 4 February. Hubei province migration scale index from 10 January to 23 January and 11 January to 24 January was correlated with the number of new confirmed COVID-19 cases per day in China except for Hubei province from 22 January to 4 February. Our findings suggested that people who left Wuhan from 9 January to 22 January, and those who left Hubei province from 10 January to 24 January, led to the outbreak in the rest of China. The ‘Wuhan lockdown’ and the launching of the first-level response to this major public health emergency may have had a good effect on controlling the COVID-19 epidemic. Although new COVID-19 cases continued to be confirmed in China outside Wuhan and Hubei provinces, in our opinion, these are second-generation cases.
This paper is a retrospective analysis of the sole transfer of monopronucleated zygotes (1PN) embryos both in in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) to determine the value of transferring embryos formed from 1PN. In fresh cycles, 1PN cleavage-stage embryos (1PN cleavage fresh) were transferred. In frozen–thawed cycles, 1PN blastocyst-stage embryos (1PN blast frozen) were transferred. We used comparison groups: for fresh cycles, 2PN cleavage-stage embryos (2PN cleavage fresh) were transferred; and for frozen–thawed cycles, 2PN blastocyst-stage embryos (2PN blast frozen) were transferred. Comparison groups were matched for cycle and patient characteristics to the 1PN group. Finally, for fresh cycles, live birth rates (LBR) in the 1PN cleavage group were significantly lower than those in 2PN cleavage group, both for IVF [LBR = 7.64% vs. pregnancy rate (PR) = 22.12%, P = 0.003, respectively] and ICSI (LBR = 0% vs. LBR = 20.00%, P < 0.001, respectively). For frozen–thawed IVF cycles, the PR in the 1PN blastocyst group were comparable with those of the 2PN blastocyst group (1PN: LBR = 33.14% vs. 2PN: LBR = 37.24%, P = 0.289, respectively), while in ICSI, the PR in the 1PN blastocyst group were lower than those in the 2PN blastocyst group (LBR = 15.25% vs. LBR = 40.68%, P = 0.002, respectively). So, for IVF, blastocyst culture was capable of selecting normal 1PN embryos for transfer and achieves satisfying outcomes. However, for ICSI, blastocyst culture was not effective enough to eliminate abnormal embryos and 1PN embryo transfer needed to be treated with caution.
To explore whether different polyvinylpyrrolidone (PVP) concentrations affect the results of intracytoplasmic sperm injection (ICSI), a prospective study was conducted for 194 couples undergoing 210 ICSI therapy cycles. These cycles were divided into three groups (10, 7 and 5% groups) using the corresponding concentration of PVP for sperm immobilization. The main outcome measures were analyzed. Results indicated that, with a decrease in PVP concentrations, all of the main outcome measures increased. In particular, the high-quality cleavage embryo rate in the 7% group was significantly lower than in the 5% group (P < 0.01), and the cleavage, high-quality cleavage embryo, and high-quality blastocyst rates in the 5% group were significantly higher than those in the 10% group (all P < 0.001). For high-/intermediate-quality semen, all of the main outcome measures were significantly increased with 5% PVP. For the poor-quality semen, only the high-quality cleavage embryo and high-quality blastocyst rates were significantly higher in the 5% group. Therefore, lowering PVP concentrations greatly promoted the development of embryos in ICSI cycles, with an optimal concentration of 5% for ICSI.
The aim of the present study was to explore the influence of tea consumption on diabetes mellitus in the Chinese population. This multi-centre, cross-sectional study was conducted in eight sites from south, east, north, west and middle regions in China by enrolling 12 017 subjects aged 20–70 years. Socio-demographic and general information was collected by a standardised questionnaire. A standard procedure was used to measure anthropometric characteristics and to obtain blood samples. The diagnosis of diabetes was determined using a standard 75-g oral glucose tolerance test. In the final analysis, 10 825 participants were included and multiple logistic models and interaction effect analysis were applied for assessing the association between tea drinking with diabetes. Compared with non-tea drinkers, the multivariable-adjusted OR for newly diagnosed diabetes were 0·80 (95 % CI 0·67, 0·97), 0·88 (95 % CI 0·71, 1·09) and 0·86 (95 % CI 0·67, 1·11) for daily tea drinkers, occasional tea drinkers and seldom tea drinkers, respectively. Furthermore, drinking tea daily was related to decreased risk of diabetes in females by 32 %, elderly (>45 years) by 24 % and obese (BMI > 30 kg/m2) by 34 %. Moreover, drinking dark tea was associated with reduced risk of diabetes by 45 % (OR 0·55; 95 % CI 0·42, 0·72; P < 0·01). The results imply that drinking tea daily was negatively related to risk of diabetes in female, elderly and obese people. In addition, drinking dark tea was associated with decreased risk of type 2 diabetes mellitus.
Flaxseed oil is rich in α-linolenic acid (ALA), which is the metabolic precursor of EPA and DHA. The present study investigated the effect of flaxseed oil supplementation on lipopolysaccharide (LPS)-induced muscle atrophy and carbohydrate oxidation impairment in a piglet model. Twenty-four weaned pigs were used in a 2 × 2 factorial experiment including dietary treatment (5 % maize oil v. 5 % flaxseed oil) and LPS challenge (saline v. LPS). On day 21 of treatment, the pigs were injected intraperitoneally with 100 μg/kg body weight LPS or sterile saline. At 4 h after injection, blood, gastrocnemius muscle and longissimus dorsi muscle were collected. Flaxseed oil supplementation increased ALA, EPA, total n-3 PUFA contents, protein:DNA ratio and pyruvate dehydrogenase complex quantity in muscles (P < 0·05). In addition, flaxseed oil reduced mRNA expression of toll-like receptor (TLR) 4 and nucleotide-binding oligomerisation domain protein (NOD) 2 and their downstream signalling molecules in muscles and decreased plasma concentrations of TNF-α, IL-6 and IL-8, and mRNA expression of TNF-α, IL-1β and IL-6 (P < 0·05). Moreover, flaxseed oil inclusion increased the ratios of phosphorylated protein kinase B (Akt) 1:total Akt1 and phosphorylated Forkhead box O (FOXO) 1:total FOXO1 and reduced mRNA expression of FOXO1, muscle RING finger (MuRF) 1 and pyruvate dehydrogenase kinase 4 in muscles (P < 0·05). These results suggest that flaxseed oil might have a positive effect on alleviating muscle protein loss and carbohydrates oxidation impairment induced by LPS challenge through regulation of the TLR4/NOD and Akt/FOXO signalling pathways.
In order to reveal the quantitative relationship between fatigue crack deflection path and cross-sectional grain boundary (GB) arrangement of metallic nanolayered composites (NLCs), a stochastic model was established based on the interface-dominant fatigue damage for the ultrafine-scale NLCs. The model indicates that the crack deflection length decreases with decreasing GB arrangement deviation and grain size of constituent layers. The observation and quantitative analysis of fatigue cracking behavior of the Cu/W multilayers with a layer thickness of 5 and 20 nm was conducted to verify the model.
Schizophrenia is a complex mental disorder with high heritability and polygenic inheritance. Multimodal neuroimaging studies have also indicated that abnormalities of brain structure and function are a plausible neurobiological characterisation of schizophrenia. However, the polygenic effects of schizophrenia on these imaging endophenotypes have not yet been fully elucidated.
To investigate the effects of polygenic risk for schizophrenia on the brain grey matter volume and functional connectivity, which are disrupted in schizophrenia.
Genomic and neuroimaging data from a large sample of Han Chinese patients with schizophrenia (N = 509) and healthy controls (N = 502) were included in this study. We examined grey matter volume and functional connectivity via structural and functional magnetic resonance imaging, respectively. Using the data from a recent meta-analysis of a genome-wide association study that comprised a large number of Chinese people, we calculated a polygenic risk score (PGRS) for each participant.
The imaging genetic analysis revealed that the individual PGRS showed a significantly negative correlation with the hippocampal grey matter volume and hippocampus–medial prefrontal cortex functional connectivity, both of which were lower in the people with schizophrenia than in the controls. We also found that the observed neuroimaging measures showed weak but similar changes in unaffected first-degree relatives of patients with schizophrenia.
These findings suggested that genetically influenced brain grey matter volume and functional connectivity may provide important clues for understanding the pathological mechanisms of schizophrenia and for the early diagnosis of schizophrenia.
M3:2 high-speed steel (HSS) billets with or without Nb addition were prepared by spray deposition. The effects of Nb and post-thermal-mechanical processing (decomposition treatment and hot forging), as well as heat treatment, on the microstructure and properties of M3:2 HSS were investigated. The microstructure of the as-deposited M3:2 HSS consisted of equiaxed grains with a mean size of approximately 25 μm and discontinuous plate-like M2C and irregular MC carbides distributed along grain boundaries. 0.5% Nb addition can refine the M2C plates and spheroidize MC carbides. With 2% Nb addition, the refined grains with a mean size of approximately 12 μm and continuous net of M6C and a uniform distribution of NbC carbides were obtained. The decomposition of metastable M2C carbides can be accelerated with 0.5% Nb addition due to the refined size and lower thermodynamic stability of M2C plates. With the increased degree of decomposition of M2C carbide, the M6C and MC carbides became refined and more uniformly distributed after optimal thermal-mechanical processing and heat treatment, which leads to a significant increase in bend strength and toughness.
FM-to-AM (frequency modulation-to-amplitude modulation) conversion caused by nonuniform spectral transmission of broadband beam is harmful to high-power laser facility. Smoothing by spectral dispersion (SSD) beam is a special broadband beam for its monochromatic feature at the given time and space on the near field. The traditional method which uses the optical spectral transfer function as filters cannot accurately describe its AM characteristics. This paper presents the theoretical analysis of the etalon effect for SSD beam. With a low-order approximation, the analytic model of the temporal shape of SSD beam is obtained for the first time, which gives the detailed AM characteristics at local and integral aspects, such as the variation of ripples width and amplitude in general situation. We also analyze the FM-to-AM conversion on the focal plane; in the focusing process, the lens simply acts as an integrator to smooth the AM of SSD beam. Because AM control is necessary for the near field to avoid optics damage and for the far field to ensure an optimal interaction of laser–target, our investigations could provide some important phenomena and rules for pulse shape control.
In this paper, we reported both the experimental demonstration and theoretical analysis of a Raman fiber laser based on a master oscillator–power amplifier configuration. The Raman fiber laser adopted the dual-wavelength bidirectional pumping configuration, utilizing 976 nm laser diodes and 1018 nm fiber lasers as the pump sources. A 60-m-long
ytterbium-doped fiber was used to convert the power from 1070 to 1124 nm, realizing a maximum power output of 3.7 kW with a 3 dB spectral width of 6.8 nm. Moreover, we developed a multi-frequency model taking into consideration the Raman gain spectrum and amplified spontaneous emission. The calculated spectral broadening of both the forward and backward laser was in good agreement with the experimental results. Finally, a 1.5 kW, 1183 nm second-order Raman fiber laser was further experimentally demonstrated by the addition of a 70-m-long germanium-doped passive fiber.
Haxilegen Glacier No.51 (43.731°N, 84.391°E; CN5Y741C0051) is located in the Kuytun river basin, Erenharbirga range, eastern Tien Shan. This study presents the annual mass balance of Haxilegen Glacier No.51 for 7 hydrological years and uses a temperature-index and an accumulation model to reconstruct the annual mass balance from 1999 to 2015. The model is calibrated against annual altitudinal mass-balance measurements and then applied to the period with no measurements. We find an accumulated mass balance of −6.06 ± 0.88 m w.e.a−1 over the period of 16 hydrological years, with an average annual value of −0.32 ± 0.22 m w.e.a−1. The mean glacier-wide annual, summer and winter balances for 1999 to 2015 are −0.37, −0.54 and 0.16 ± 0.22 m w.e.a−1, respectively, with a high correlation coefficient (r = 0.95, p < 0.001) between annual balance and summer balance. The calculated mass-balance sensitivity of the glacier to temperature is −0.51 m w.e.a−1 °C−1 and to precipitation is 0.08 m w.e.a−1 for a 10% increase. The sensitivity of seasonal mass balance indicates that temperature during the melt season (May–August) and annual precipitation are the major contributors to mass-balance fluctuation.
Specific adipokines, such as adiponectin and resistin, are secreted from adipose tissue and are associated with the development of obesity. Supplementation of dietary SCFA can prevent and reverse high-fat-diet (HFD)-induced obesity. However, it is not clear whether SCFA ameliorate abnormal expression of adiponectin and resistin in the obese state. The aim of this study was to investigate the effects of SCFA on adiponectin and resistin’s expressions in diet-induced obese mice, as well as the potential mechanisms associated with DNA methylation. C57BL/6J male mice were fed for 16 weeks with five types of HFD (34·9 % fat by wt., 60 % kJ) – a control HFD and four HFD with acetate (HFD-A), propionate (HFD-P), butyrate (HFD-B) and their admixture (HFD-SCFA). Meanwhile, a low-fat diet (4·3 % fat by wt., 10 % kJ) was used as the control group. The reduced mRNA levels of adiponectin and resistin in the adipose tissue of the HFD-fed mice were significantly reversed by dietary supplementation of acetate, propionate, butyrate or their admixture to the HFD. Moreover, the expressional changes of adiponectin and resistin induced by SCFA were associated with alterations in DNA methylation at their promoters, which was mediated by reducing the expressions of enzyme-catalysed DNA methyltransferase (DNMT1, 3a, 3b) and the methyl-CpG-binding domain protein 2 (MBD2) and suppressing the binding of these enzymes to the promoters of adiponectin and resistin. Our results indicate that SCFA may correct aberrant expressions of adiponectin and resistin in obesity by epigenetic regulation.
In high power laser facility for inertial confinement fusion research, final optics assembly (FOA) plays a critical role in the frequency conversion, beam focusing, color separation, beam sampling and debris shielding. The design and performance of FOA in SG-II Upgrade laser facility are mainly introduced here. Due to the limited space and short focal length, a coaxial aspheric wedged focus lens is designed and applied in the FOA configuration. Then the ghost image analysis, the focus characteristic analysis, the B integral control design and the optomechanical design are carried out in the FOA design phase. In order to ensure the FOA performance, two key technologies are developed including measurement and adjustment technique of the wedged focus lens and the stray light management technique based on ground glass. Experimental results show that the design specifications including laser fluence, frequency conversion efficiency and perforation efficiency of the focus spot have been achieved, which meet the requirements of physical experiments well.
In this paper, we review the status of the multifunctional experimental platform at the National Laboratory of High Power Laser and Physics (NLHPLP). The platform, including the SG-II laser facility, SG-II 9th beam, SG-II upgrade (SG-II UP) facility, and SG-II 5 PW facility, is operational and available for interested scientists studying inertial confinement fusion (ICF) and a broad range of high-energy-density physics. These facilities can provide important experimental capabilities by combining different pulse widths of nanosecond, picosecond, and femtosecond scales. In addition, the SG-II UP facility, consisting of a single petawatt system and an eight-beam nanosecond system, is introduced including several laser technologies that have been developed to ensure the performance of the facility. Recent developments of the SG-II 5 PW facility are also presented.