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Hand, foot, and mouth disease (HFMD) is a common infectious disease in the Asia-Pacific region that primarily affects children younger than 5 years. Previous studies have confirmed that the seasonal transmission of this disease is strongly related to meteorological factors, but the results are not consistent. In addition, the associations between weather conditions and HFMD in northwestern China have not been investigated. Therefore, we aimed to examine this issue in Xi’an, the largest city of northwestern China that has been suffering from serious HFMD epidemics. In the current study, data for HFMD and six meteorological factors were collected from 2009 to 2018. Using cross-correlation analysis, the Granger causality test, and the distributed lag nonlinear model, we estimated the quantitative relationships and exposure-lag–response effects between weekly meteorological factors and HFMD incidence among children. We found that the seasonal distribution of HFMD in Xi’an has two peaks each year and is significantly impacted by the weekly temperature, precipitation, and evaporation over an 8-week period. Higher values of temperature and evaporation had positive associations with disease transmission, whereas the association between precipitation and HFMD showed an inverted-U shape. The maximum relative risks (RRs) of HFMD for the weekly mean temperature (approximately 31.1°C), weekly cumulative evaporation (57.9 mm), and weekly cumulative precipitation (30.0 mm) were 1.56 (95% CI: 1.35–1.81), 1.40 (95% CI: 1.05–1.88), and 1.16 (95% CI: 1.11–1.70), respectively. The identified risk determinants and lag effects could provide important information for early interventions to reduce the local disease burden.

Background The unprecedented outbreak of corona virus disease 2019 (COVID-19) infection in Wuhan City has caused global concern; the outflow of the population from Wuhan was believed to be a main reason for the rapid and large-scale spread of the disease, so the government implemented a city-closure measure to prevent its transmission considering the large amount of travel before the Chinese New Year. Methods Based on the daily reported new cases and the population-movement data between 1 and 31 January, we examined the effects of population outflow from Wuhan on the geographical expansion of the infection in other provinces and cities of China, as well as the impacts of the city closure in Wuhan using different closing-date scenarios. Results We observed a significantly positive association between population movement and the number of the COVID-19 cases. The spatial distribution of cases per unit of outflow population indicated that the infection in some areas with a large outflow of population might have been underestimated, such as Henan and Hunan provinces. Further analysis revealed that if the city-closure policy had been implemented 2 days earlier, 1420 (95% confidence interval, 1059–1833) cases could have been prevented, and if 2 days later, 1462 (1090–1886) more cases would have been possible. Conclusions Our findings suggest that population movement might be one important trigger for the transmission of COVID-19 infection in China, and the policy of city closure is effective in controlling the epidemic.

ObjectiveTo determine the characteristics and spatiotemporal distribution of major gastrointestinal (GI) neoplasms in inpatients from 1995 to 2016 in Wuwei city, northwestern China.MethodData from all paper and electronic medical records entered between 1995 and 2016 at 12 major public hospitals in Wuwei city were retrospectively collected. Patients with GI neoplasms were identified and classified according to the International Classification of Diseases (ICD)-10. Trends in the incidence of major GI neoplasms were expressed as an annual percentage change (APC), and the Z test was used to assess the time fluctuation trends. Age-standardized incidence rates (ASIRs) were also calculated and the corresponding APC was estimated by the Joinpoint software for long-term trend analysis. Thematic maps of annual incidence at the township level were produced.ResultsAmong the 19,137 new inpatients identified with GI neoplasms in Wuwei, gastric cancer was the leading cause of morbidity, followed by cancers of the esophagus, colorectum, gastric cardia, liver, and pancreas with ASIRs of 21.8, 11.0, 5.8, 5.7, 4.4, and 1.7 per 100,000 person-years, respectively. Overall, there was a steady increase in the ASIR for all GI neoplasms, and male cases were 2.1 times more frequent than female cases. The ASIR significantly increased by 12.2% per year from 1995 to 2009 for all GI neoplasms, and the increase rates ranged 9.4%-16.7% per year for the individual GI neoplasm. Despite an increase by 1.4% per year from 2009 to 2016, the ASIR decreased for esophageal and gastric cardia cancers by 4.6% and 17.3% per year, respectively. The annual incidence of all GI neoplasms showed significantly differential geographic distributions among different townships of the city during the study period.

With the rapid development of electric vehicle industry in China, the contradiction between the increasing users' demand for real-time charging and the unbalanced planning and design of charging piles is increasingly apparent. DC charging pile on the market is developed rapidly, but its structure is with multi-gun to one-pile. It is difficult to meet the demand of different kinds of electric vehicle battery charging, different battery capacity and the user expected charging time. To solve the problems, a flexible power distribution method of DC charging pile is proposed in this paper. When multiple EV in different types and states are charged at the same time, and the actual charging demands of each user and the charging battery are considered, the power module can be dynamically switched to realize the flexible power distribution, the idea of flexible power distribution is described. Then the algorithm steps of power distribution were presented. Finally, the Matlab/Simulink was used for example analysis to simulate the power distribution process when different initial SOC batteries were charged simultaneously.

BACKGROUND At the beginning of the COVID-19 pandemic, a cluster outbreak caused by an imported case from Hubei Province was reported in Xi'an City, Shaanxi Province, China. Ten patients from 2 families and 1 hospital were involved in the transmission. MATERIAL AND METHODS We conducted an epidemiological investigation to identify the cluster transmission of COVID-19. The demographic, epidemiological, clinical, laboratory, and cluster characteristics were described and analyzed. RESULTS From January 27 to February 13, 2020, a total of 10 individuals were confirmed to be infected with SARS-CoV-2 by the nucleic acid testing of nasopharyngeal swabs from 2 families and 1 hospital. Among the confirmed cases, 7 had atypical clinical symptoms and 3 were asymptomatic. The median times from onset to diagnosis and to discharge were 3.5 days (range, 1-5 days) and 19.5 days (range, 16-38 days), respectively. There were 4 patients whose exposure dates were 1, 3, 3, and 2 days earlier than the onset dates of their previous-generation cases, respectively. Four prevention and control measures were effectively used to interrupt the disease transmission. CONCLUSIONS SARS-CoV-2 can be easily transmitted within families and in hospitals, and asymptomatic patients could act as a source of disease transmission. The results of this outbreak at the early epidemic stage support the recommendation that individuals with confirmed COVID-19 and all their close contacts should be subjected to medical quarantined observation and nucleic acid screening as early as possible, even if they do not have any symptoms. Meanwhile, people in high-risk areas should improve their protective measures.

Wireless power transfer (WPT) plays a crucial role in battery charging of electric vehicles (EVs). In order to compensate for leakage inductance and magnetizing inductance, the resonant compensation topology is usually added to the magnetically coupled resonant wireless power transfer system (MCR-WPTS). The S-S compensation topology is studied and analyzed. A detailed mathematical model and a simulation model are established. The expressions of output current, voltage and transmission power are derived. The relationship between the input, output current, output voltage, transmission power and load and mutual inductance of S-S compensation topology is shown by simulation. The simulation shows consistent results with the analysis. In addition, this paper analyzes the sensitivity of the capacitance parameters in the Matlab/Simulink simulation model, and obtains the changing trend of the transmission power of the system with the capacitance parameters, which provides support for the further research on the selection of capacitance parameters.

Background Human brucellosis imposes a heavy burden on the health and economy of endemic regions. Since 2011, China has reported at least 35,000 human brucellosis cases annually, with more than 90% of these cases reported in the northern. Given the alarmingly high incidence and variation in the geographical distribution of human brucellosis cases, there is an urgent need to decipher the causes of such variation in geographical distribution. Method We conducted a retrospective epidemiological study in Shaanxi Province from January 1, 2005 to December 31, 2018 to investigate the association between meteorological factors and transmission of human brucellosis according to differences in geographical distribution and seasonal fluctuation in northwestern China for the first time. Results Human brucellosis cases were mainly distributed in the Shaanbei upland plateau before 2008 and then slowly extended towards the southern region with significant seasonal fluctuation. The results of quasi-Poisson generalized additive mixed model (GAMM) indicated that air temperature, sunshine duration, rainfall, relative humidity, and evaporation with maximum lag time within 7 months played crucial roles in the transmission of human brucellosis with seasonal fluctuation. Compared with the Shaanbei upland plateau, Guanzhong basin had more obvious fluctuations in the occurrence of human brucellosis due to changes in meteorological factors. Additionally, the established GAMM model showed high accuracy in predicting the occurrence of human brucellosis based on the meteorological factors. Conclusion These findings may be used to predict the seasonal fluctuations of human brucellosis and to develop reliable and cost-effective prevention strategies in Shaanxi Province and other areas with similar environmental conditions.