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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.
For the guarantee of the long-distance transport of the bunches of China Initiative Accelerator Driven System (CIADS), a new scheme is proposed that extra magnetic field is used in the accelerator-target coupling section before the windowless target to minimize the self-modulation (SM) mechanism. Particle-in-cell simulations are carried out to study the influence of the solenoidal magnetic field on the self-modulation mechanism when long proton bunches move in the background plasmas. The long proton bunches used in the simulations are similar to these in the linear accelerator of CIADS. It is found that the presence of the solenoidal magnetic field will significantly inhibit the self-modulation process. For the strong magnetic field, the longitudinal separation and transverse focusing of the long bunches disappear. We attribute these phenomena to the reason that the strong solenoidal magnetic field restricts the transverse movement of plasma electrons. Thus, there are not enough electrons around the bunch to compensate the space charge effect. Moreover, without transverse current, the longitudinal pinched effect disappears, and the long bunch can not be separated into small pulses anymore.
The effects of macronutrient intake on obesity are controversial. This research aims to investigate the associations between macronutrient intake and new-onset overweight/obesity. The relationship between the consumption of carbohydrate and total fat and obesity was assessed by the multivariable Cox model in this 11-year cohort, which included 6,612 adults (3,321 women and 3,291 men) who were free of overweight and obesity at baseline. The dietary intake was recorded using a 24-h recall method for three consecutive days. Moreover, substitution models were developed to distinguish the effects of macronutrient composition alteration from energy intake modification. During 7.5 person years (IQR 4.3-10.8) of follow-up, 1,807 participants became overweight or obesity. After adjusting for risk factors, the HR of overweight/obesity in extreme quintiles of fat was 1.48 (quintile 5 vs quintile 1, 95% CI, 1.16-1.89; Ptrend =0.02) in women. Additionally, replacing 5% of energy from carbohydrate with equivalent energy from fat was associated with an estimated 4.3% (HR, 1.043; 95% CI, 1.007-1.081) increase in overweight/obesity in women. Moreover, dietary carbohydrate was inversely associated with overweight/obesity (quintile 5 vs quintile 1, HR, 0.70; 95% CI, 0.55-0.89; Ptrend =0.02) in women. Total fat was related to a higher risk of overweight/obesity, whereas high carbohydrate intake was related to a lower risk of overweight/obesity in women, which was not observed in men.
In the present work, the ankle rehabilitation robot (ARR) dynamic model that implements a new series of connection control strategies is introduced. The dynamic models are presented in this regard. This model analyzes the robot LuGre friction model and the nonlinear disturbance model. To improve the ARR system’s rapidity and robustness, a composite 2-degree of freedom (2-DOF) internal model control (IMC) controller is presented. The control performance of the compound 2-DOF IMC controller is simulated and analyzed in the present work. The simulation shows that the composite 2-DOF IMC controller has high following performance. For practical testing purposes, 1-DOF passive training and predetermined trajectory following have been completed for different swing amplitudes and frequencies. Moreover, the thrust and tension torque of the robotic dynamic and static loading characteristics are studied in active control mode. The experimental results show the effectiveness of passive training of the given trajectory and impedance training active control strategy. This paper gives the specific functions of ARR.
Dietary salt intake may vary depending on different lifestyles. We aimed to estimate the different salt intakes and evaluate the knowledge and self-awareness about salt among people speaking the Teochew, Teochew–Hakka and Hakka dialects in the Chaoshan region of southern China.
The study followed a cluster sampling of residents in Chaoshan region. General characteristics, lifestyles, health status as well as knowledge and self-awareness related to salt intake were investigated using a questionnaire. Anthropometric variables as well as Na and K excretion in a 24-h urine collection were measured.
Chaoshan region of China.
Four hundred fifteen adults who spoke only one of these three dialects.
The salt intake of adults who spoke the Teochew, Teochew–Hakka and Hakka dialects was 7·19 (interquartile range (IQR) 5·29–10·17), 9·03 (IQR 6·62–11·54) and 10·12 (IQR 7·61–12·82) g/d, respectively, with significant differences between Teochew and Teochew–Hakka speakers and between Teochew and Hakka speakers (both P < 0·05). The Na:K ratio for adults who spoke the three dialects was 3·00 (IQR 2·00–4·11), 3·50 (IQR 2·64–4·82) and 4·52 (IQR 3·35–5·97), respectively, and differed significantly among the groups (all P < 0·05). Multiple linear regression analysis showed increased Na:K ratio associated with hypertension (β = 0·71, P = 0·043) in Hakka speakers. Knowledge and self-awareness about salt intake were poor in this population.
Salt intake was closely related to lifestyles and was higher than the upper limit (5 g/d) recommended by the WHO in adults of Chaoshan, especially those speaking the Hakka dialect.
Age effects may be important for improving models for the prediction of conversion to psychosis for individuals in the clinical high risk (CHR) state. This study aimed to explore whether adolescent CHR individuals (ages 9–17 years) differ significantly from adult CHR individuals (ages 18–45 years) in terms of conversion rates and predictors.
Consecutive CHR individuals (N = 517) were assessed for demographic and clinical characteristics and followed up for 3 years. Individuals with CHR were classified as adolescent (n = 244) or adult (n = 273) groups. Age-specific prediction models of psychosis were generated separately using Cox regression.
Similar conversion rates were found between age groups; 52 out of 216 (24.1%) adolescent CHR individuals and 55 out of 219 (25.1%) CHR adults converted to psychosis. The conversion outcome was best predicted by negative symptoms compared to other clinical variables in CHR adolescents (χ2 = 7.410, p = 0.006). In contrast, positive symptoms better predicted conversion in CHR adults (χ2 = 6.585, p = 0.01).
Adolescent and adult CHR individuals may require a different approach to early identification and prediction. These results can inform the development of more precise prediction models based on age-specific approaches.
There has been no study exploring the prognostic values of neutrophil percentage-to-albumin ratio (NPAR). We hypothesised that NPAR is a novel marker of inflammation and is associated with all-cause mortality in patients with severe sepsis or septic shock. Patient data were extracted from the MIMIC-III V1.4 database. Only the data for the first intensive care unit (ICU) admission of each patient were used and baseline data were extracted within 24 h after ICU admission. The clinical endpoints were 30-, 90- and 365-day all-cause mortality in critically ill patients with severe sepsis or septic shock. Cox proportional hazards models and subgroup analyses were used to determine the relationship between NPAR and these clinical endpoints. A total of 2166 patients were eligible for this analysis. In multivariate analysis, after adjustments for age, ethnicity and gender, higher NPAR was associated with increased risk of 30-, 90- and 365-day all-cause mortality in critically ill patients with severe sepsis or septic shock. Furthermore, after adjusting for more confounding factors, higher NPAR remained a significant predictor of all-cause mortality (tertile 3 vs. tertile 1: HR, 95% CI: 1.29, 1.04–1.61; 1.41, 1.16–1.72; 1.44, 1.21–1.71). A similar trend was observed in NPAR levels stratified by quartiles. Higher NPAR was associated with increased risk of all-cause mortality in critically ill patients with severe sepsis or septic shock.
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.
Evidence on the relationship between maternal Hb concentration and spontaneous abortion (SA) risk is limited and conflicting. The purpose of the study was to evaluate whether maternal preconception anaemia or high Hb concentration is associated with risk of SA.
A population-based cohort study established between 2013 and 2017.
Local maternal and child care service centres in each county.
In total, 3 971 428 women aged 20–49 years, who participated in National Free Pre-Pregnancy Checkups Project from 2013 to 2016 and successfully got pregnant before 2017 in rural China.
A total of 101 700 (2·56 %) women were recorded having SA, with highest SA rate in women with severe anaemia (4·58 %). Compared with women with Hb of 110–149 g/l, the multivariable-adjusted OR for SA was 1·52 (95 % CI: 1·25, 1·86) for women with Hb < 70 g/l, 0·92 (0·84, 1·01) for 70–99 g/l, 0·80 (0·77, 0·83) for 100–109 g/l, 1·11 (1·08, 1·15) for 150–159 g/l, 1·12 (1·04, 1·20) for 160–169 g/l and 1·02 (0·93, 1·12) for ≥ 170 g/l, respectively. An approximate U-shaped curve for the risk of SA with Hb concentrations was observed when Hb concentrations less than 145 g/l, above which the association plateaued (Pnon-linear < 0·001).
Severe anaemia and high Hb concentration before pregnancy were associated with an increased risk of SA. Women with mild anaemia prior to pregnancy had lower risk of SA. Underlying mechanisms need to be further studied.
This article presents a brief review of our case studies of data-driven Integrated Computational Materials Engineering (ICME) for intelligently discovering advanced structural metal materials, including light-weight materials (Ti, Mg, and Al alloys), refractory high-entropy alloys, and superalloys. The basic bonding in terms of topology and electronic structures is recommended to be considered as the building blocks/units constructing the microstructures of advanced materials. It is highlighted that the bonding charge density could not only provide an atomic and electronic insight into the physical nature of chemical bond of materials but also reveal the fundamental strengthening/embrittlement mechanisms and the local phase transformations of planar defects, paving a path in accelerating the development of advanced metal materials via interfacial engineering. Perspectives on the knowledge-based modeling/simulations, machine-learning knowledge base, platform, and next-generation workforce for sustainable ecosystem of ICME are highlighted, thus to call for more duty on the developments of advanced structural metal materials and enhancement of research productivity and collaboration.
In recent years, there have been a significant influenza activity and emerging influenza strains in China, resulting in an increasing number of influenza virus infections and leading to public health concerns. The aims of this study were to identify the epidemiological and aetiological characteristics of influenza and establish seasonal autoregressive integrated moving average (SARIMA) models for forecasting the percentage of visits for influenza-like illness (ILI%) in urban and rural areas of Shenyang. Influenza surveillance data were obtained for ILI cases and influenza virus positivity from 18 sentinel hospitals. The SARIMA models were constructed to predict ILI% for January–December 2019. During 2010–2018, the influenza activity was higher in urban than in rural areas. The age distribution of ILI cases showed the highest rate in young children aged 0–4 years. Seasonal A/H3N2, influenza B virus and pandemic A/H1N1 continuously co-circulated in winter and spring seasons. In addition, the SARIMA (0, 1, 0) (0, 1, 2)12 model for the urban area and the SARIMA (1, 1, 1) (1, 1, 0)12 model for the rural area were appropriate for predicting influenza incidence. Our findings suggested that there were regional and seasonal distinctions of ILI activity in Shenyang. A co-epidemic pattern of influenza strains was evident in terms of seasonal influenza activity. Young children were more susceptible to influenza virus infection than adults. These results provide a reference for future influenza prevention and control strategies in the study area.
In order to improve the training efficiency and establish a multi-person cooperative training simulation system, including “virtual human,” in the process of virtual reality-based astronaut training, it is necessary to plan the velocity at which astronauts carry the target object. A velocity planning algorithm, combining a traditional six-stage acceleration/deceleration algorithm, based on a time-discrete model with high-order dynamic constraints, considering the elastic damping torque of the space suit, is proposed. The described algorithm is verified on MATLAB to prove its feasibility. Compared to other algorithms, the planning time of the proposed algorithm is significantly reduced.
Aiming at the influence of coupling coefficient variation on the output voltage of a high-power LCC-S topology inductively coupled power transfer (ICPT) system, a synchronous three-phase triple-parallel Buck converter is used as the voltage adjustment unit. The control method for the three-phase current sharing of synchronous three-phase triple-parallel Buck converter and the constant voltage output ICPT system under the coupling coefficient variation is studied. Firstly, the hybrid model consisting of the circuit averaging model of the three-phase triple-parallel Buck converter and the generalized state-space average model for the LCC-S type ICPT system is established. Then, the control methods for three-phase current sharing of the synchronous three-phase triple-parallel Buck converter and constant voltage output of ICPT system are studied to achieve the multi-objective integrated control of the system. Finally, a 3.3 kW wireless charging system platform is built, the experimental results have verified the effectiveness of the proposed modeling and control method, and demonstrated the stability of the ICPT system.
Identifying risk factors and mortality of individuals with Alzheimer’s disease (AD) could have important implications for the clinical management of AD.
This pilot study aimed to examine the overall mortality of AD patients over a 10-year surveillance period in Shanghai, China. This study is an extension of our previous investigation on mortality of neurodegenerative diseases.
One hundred and thirty-two AD patients recruited from the memory clinics of two hospitals in Shanghai in 2007 were followed up until December 31, 2017 or death, representing a follow-up period of up to 10 years. Overall standardized mortality ratios (SMRs) were calculated, and predictors for survival at recruitment were estimated.
Sixty-seven patients had died by December 31, 2017, and the SMR at 10 years of follow-up was 1.225 (95% confidence interval 0.944–1.563). Employing Cox’s proportional hazard modeling, lower Mini-Mental State Examination score, and comorbid diabetes predicted poor survival in this cohort.
This pilot study suggests a similar survival trend of patients with AD compared to the general population in Shanghai urban region. Poor cognitive status and comorbid diabetes had a negative impact on the survival of AD patients.
Synaptotagmin 1 (Syt1) is an abundant and important presynaptic vesicle protein that binds Ca2+ for the regulation of synaptic vesicle exocytosis. Our previous study reported its localization and function on spindle assembly in mouse oocyte meiotic maturation. The present study was designed to investigate the function of Syt1 during mouse oocyte activation and subsequent cortical granule exocytosis (CGE) using confocal microscopy, morpholinol-based knockdown and time-lapse live cell imaging. By employing live cell imaging, we first studied the dynamic process of CGE and calculated the time interval between [Ca2+]i rise and CGE after oocyte activation. We further showed that Syt1 was co-localized to cortical granules (CGs) at the oocyte cortex. After oocyte activation with SrCl2, the Syt1 distribution pattern was altered significantly, similar to the changes seen for the CGs. Knockdown of Syt1 inhibited [Ca2+]i oscillations, disrupted the F-actin distribution pattern and delayed the time of cortical reaction. In summary, as a synaptic vesicle protein and calcium sensor for exocytosis, Syt1 acts as an essential regulator in mouse oocyte activation events including the generation of Ca2+ signals and CGE.
The microbiota–gut–brain axis, especially the microbial tryptophan (Trp) biosynthesis and metabolism pathway (MiTBamp), may play a critical role in the pathogenesis of major depressive disorder (MDD). However, studies on the MiTBamp in MDD are lacking. The aim of the present study was to analyze the gut microbiota composition and the MiTBamp in MDD patients.
We performed shotgun metagenomic sequencing of stool samples from 26 MDD patients and 29 healthy controls (HCs). In addition to the microbiota community and the MiTBamp analyses, we also built a classification based on the Random Forests (RF) and Boruta algorithm to identify the gut microbiota as biomarkers for MDD.
The Bacteroidetes abundance was strongly reduced whereas that of Actinobacteria was significantly increased in the MDD patients compared with the abundance in the HCs. Most noteworthy, the MDD patients had increased levels of Bifidobacterium, which is commonly used as a probiotic. Four Kyoto Encyclopedia of Genes and Genomes (KEGG) orthologies (KOs) (K01817, K11358, K01626, K01667) abundances in the MiTBamp were significantly lower in the MDD group. Furthermore, we found a negative correlation between the K01626 abundance and the HAMD scores in the MDD group. Finally, RF classification at the genus level can achieve an area under the receiver operating characteristic curve of 0.890.
The present findings enabled a better understanding of the changes in gut microbiota and the related Trp pathway in MDD. Alterations of the gut microbiota may have the potential as biomarkers for distinguishing MDD patients form HCs.