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Spatiotemporal variations of ambient air pollutants and meteorological influences over typical urban agglomerations in China during the COVID-19 lockdown

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Journal of Environmental Sciences 2021年第8期33卷 26-38页

作者： Linping Fan Shuang Fu Xin Wang Qingyan Fu Haohao Jia Hao Xu Guimei Qin Xue Hu Jinping Cheng School of Environmental Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China China National Environmental monitoring center Beijing 100012China Shanghai Environmental monitor center Shanghai 200235China

To investigate the air quality change during the COVID-19 pandemic,we analyzed spatiotemporal variations of six criteria pollutants in nine typical urban agglomerations in China using ground-based data and examined meteorological influences through correlation analysis and backward trajectory analysis under different *** of PM2.5,PM10,NO2,SO2 and CO in urban agglomerations respectively decreased by 18%–45%(30%–62%),17%–53%(22%–39%),47%-64%(14%–41%),9%–34%(0%–53%)and 16%-52%(23%–56%)during Lockdown(Post-lockdown)period relative to Pre-lockdown ***2.5 pollution events occurred during Lockdown in Beijing-Tianjin-Hebe(BTH)and Middle and South Liaoning(MSL),and daily O3 concentration rose to gradeⅡstandard in Post-lockdown *** from the nationwide slump of NO2 during Lockdown period,a rebound(~40%)in Post-lockdown period was observed in Cheng-Yu(CY),Yangtze River Middle-Reach(YRMR),Yangtze River Delta(YRD)and Pearl River Delta(PRD).With slightly higher wind speed compared with 2019,the reduction of PM2.5(51%–62%)in Post-lockdown period is more than2019(15%–46%)in HC(Harbin-Changchun),MSL,BTH,CP(Central Plain)and SP(ShandongPeninsula),suggesting lockdown measures are effective to PM2.5 *** O3 concentrations generally increased during the lockdown,its increment rate declined compared with 2019 under similar sunlight duration and ***,unlike HC,MSL and BTH,which suffered from additional(>30%)air masses from surrounding areas after the lockdown,the polluted air masses reaching YRD and PRD mostly originated from the long-distance transport,highlighting the importance of joint regional governance.

关键词： COVID-19 Air pollutants Spatial and temporal variations Urban agglomeration Meteorological condition China

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WRF/CHEM modeling of impacts of weather conditions modified by urban expansion on secondary organic aerosol formation over Pearl River Delta

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Particuology 2009年第5期7卷 384-391页

作者： Xuemei Wang Zhiyong Wu Guixiong Liang School of Environmental Science and Engineering Sun Yat-sen University 135 Xingang Awest Road Guangzhou 510275 China Guangzhou Environmental monitor center Guangzhou 510010 China

In this paper, the online Weather Research and Forecasting and Chemistry （WRF/CHEM） model, coupled with urban canopy （UCM） and biogenic-emission models, is used to explore impacts of urban expansion on secondary organic aerosols （SOA） formation. Two scenarios of urban maps are used in WRF/CHEM to represent early 1990s （pre-urbanization） and current urban distribution in the Pearl River Delta （PRD）. Month-long simulation results using the above land-use scenarios for March 2001 show：（1） urbanization can increase monthly averaged temperatures by about 0.63 ℃, decrease monthly averaged 10-m wind speeds by 38%, increase monthly averaged boundary-layer depths by 80 m, and decrease monthly aver- aged water mixing ratio by 0.2g/kg. （2） Changes in meteorological conditions can result in detectable concentration changes of NOx, VOC, O3 and NO3 radicals. Urbanization decreases surface NOx and VOC concentrations by a maximum of 4 ppbv and 1.5 ppbv, respectively. Surface O3 and NO3 radical concentrations over major cities increase by about 2-4 ppbv and 4-12 pptv, respectively; areas with increasing O3 and NO3 radical concentrations generally coincide with the areas of temperature increase and wind speed reduction where NOx and VOC decrease. （3） Urbanization can induce 9% increase of SOA in Foshan, Zhongshan and west Guangzhou and 3% decrease in Shenzhen and Dongguan. Over PRD major cities, SOA from Aitken mode reduces by 30% but with more than 70% SOA from accumulate mode. Urbanization has stronger influence on SOA formation from Aitken mode. （4） Over the PRD, 55-65% SOA comes from aromatics precursors. Urbanization has strongest influence on aromatics precursors to produce SOA （14% increase）, while there is less influence on alkane precursors. Alkene precursors have negative contribution to SOA formation under urbanization situation.

关键词： Secondary organic aerosol Urban expansion WRF/CHEM model

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Predictors of Adverse Pregnancy Outcomes Following Traumatic Injuries

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Current Medical Science 2024年第3期44卷 642-647页

作者： Wan-rong LU Ping WU Gong SONG Mei-qi GU Zhe XU Li HE National Clinical Research center for Gynecology and Obstetrics Cancer Biology Research CenterTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Department of Traumatic Surgery Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China

Objective After traumatic injury in pregnant women,providing timely and appropriate management for high-risk patients is crucial for both pregnant women and *** study aimed to identify risk factors that predict adverse pregnancy outcomes after traumatic *** A retrospective cohort study including 317 pregnant patients who experienced trauma was *** collected data included general demographics,injury mechanisms and adverse pregnancy *** were divided into two subgroups based on the absence or presence of trauma-related adverse pregnancy *** and multivariate logistic regressions were conducted to estimate the associations between clinical variables and adverse pregnancy *** A total of 41(12.93%)patients experienced adverse pregnancy outcomes within the first 24 h *** study revealed that age>35 years(OR=14.995,95%CI:5.024–44.755,Pmonitor patients to prevent adverse pregnancy outcomes.

关键词： adverse pregnancy outcomes predictive factors abnormal delivery trauma

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Genetic and pathogenic characterization of new infectious bronchitis virus strains in the GVI-1 and GI-19 lineages isolated in central China

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Journal of Integrative Agriculture 2024年第7期23卷 2407-2420页

作者： Yuhan Yang Dou Wang Yaning Bai Wenyan Huang Shimin Gao Xingchen Wu Ying Wang Jianle Ren Jinxin He Lin Jin Mingming Hu Zhiwei Wang Zhongbing Wang Haili Ma Junping Li Libin Liang College of Veterinary Medicine Shanxi Agricultural UniversityJinzhong 030801China Shanxi Provincial Animal Disease Prevention and Control center Taiyuan 030000China

Avian infectious bronchitis(IB)is a highly contagious infectious disease caused by infectious bronchitis virus(IBV),which is prevalent in many countries worldwide and causes serious harm to the poultry *** present,many commercial IBV vaccines have been used for the prevention and control of IB;however,IB outbreaks occur *** this study,two new strains of IBV,SX/2106 and SX/2204,were isolated from two flocks which were immunized with IBV H120 vaccine in central *** and recombination analysis indicated that SX/2106,which was clustered into the GI-19 lineage,may be derived from recombination events of the GI-19 and GI-7 strains and the LDT3-A *** analysis showed that SX/2204 belongs to the GVI-1 lineage,which may have originated from the recombination of the GI-13 and GVI-1 strains and the H120 *** virus cross-neutralization test showed that the antigenicity of SX/2106 and SX/2204 was different from *** experiments found that both SX/2106 and SX/2204 could replicate effectively in the lungs and kidneys of chickens and cause disease and death,and H120 immunization could not provide effective protection against the two IBV *** is noteworthy that the pathogenicity of SX/2204 has significantly increased compared to the GVI-1 strains isolated previously,with a mortality rate up to 60%.Considering the continuous mutation and recombination of the IBV genome to produce new variant strains,it is important to continuously monitor epidemic strains and develop new vaccines for the prevention and control of IBV epidemics.

关键词： infectious bronchitis virus GI-19 lineage GVI-1 lineage complete genome recombination pathogenicity

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Precisely Control Relationship between Sulfur Vacancy and H Absorption for Boosting Hydrogen Evolution Reaction

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Nano-Micro Letters 2024年第4期16卷 14-24页

作者： Jing Jin Xinyao Wang Yang Hu Zhuang Zhang Hongbo Liu Jie Yin Pinxian Xi College of Chemistry and Chemical Engineering Frontiers Science Center for Rare IsotopesState Key Laboratory of Applied Organic ChemistryLanzhou UniversityLanzhou 730000People’s Republic of China

Ef fective and robust catalyst is the core of water splitting to produce ***, we report an anionic etching method to tailor the sulfur vacancy(VS) of NiS_(2) to further enhance the electrocatalytic performance for hydrogen evolution reaction(HER). With the VS concentration change from 2.4% to 8.5%, the H* adsorption strength on S sites changed and NiS_(2)-VS 5.9% shows the most optimized H* adsorption for HER with an ultralow onset potential(68 m V) and has long-term stability for 100 h in 1 M KOH media. In situ attenuated-total-reflection Fourier transform infrared spectroscopy(ATR-FTIRS) measurements are usually used to monitor the adsorption of intermediates. The S-H* peak of the Ni S_(2)-VS 5.9% appears at a very low voltage, which is favorable for the HER in alkaline media. Density functional theory calculations also demonstrate the Ni S_(2)-VS 5.9% has the optimal |ΔG^(H*)| of 0.17 e V. This work offers a simple and promising pathway to enhance catalytic activity via precise vacancies strategy.

关键词： Hydrogen evolution reaction S vacancies Nanosheet H Adsorption

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Relation between the characteristics of strong earthquake activities in Chinese mainland and the Wenchuan earthquake

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Earthquake Science 2009年第5期22卷 505-518页

作者： Xiaodong Zhang Guohua Yang Xian Lu Mingxiao Li Zhigao Yang China Earthquake Networks center Beijing 100045 China First Crustal Deformation monitor and Observation center China Earthquake Administration Tianjin 300180 China

This paper studies the relations between the great Wenchuan earthquake and the active-quiet periodic characteristics of strong earthquakes, the rhythmic feature of great earthquakes, and the grouped spatial distribution of Ms8.0 earthquakes in Chinese mainland. We also studied the relation between the Wenchuan earthquake and the stepwise migration characteristics of Ms≥7.0 earthquakes on the North-South seismic belt, the features of the energy releasing acceleration in the active crustal blocks related to the Wenchuan earthquake and the relation between the Wenchuan earthquake and the so called second-arc fault zone. The results can be summarized as follows： ① the occurrence of the Wenchuan earthquake was consistent with the activequiet periodic characteristics of strong earthquakes; ② its occurrence is consistent with the features of grouped occurrence of Ms8.0 earthquakes and follows the 25 years rhythm （each circulation experiences the same time） of great earthquakes; ③ the Wenchuan Ms8.0 earthquake follows the well known stepwise migration feature of strong earthquakes on the North-South seismic belt; ④ the location where the Wenchuan Ms8.0 earthquake took place has an obvious consistency with the temporal and spatial characteristic of grouped activity of Ms≥7.0 strong earthquakes on the second-arc fault zone; ⑤ the second-arc fault zone is not only the lower boundary for earthquakes with more than 30 km focal depth, but also looks like a lower boundary for deep substance movement; and ⑥ there are obvious seismic accelerations nearby the Qaidam and Qiangtang active crustal blocks （the northern and southern neighbors of the Bayan Har active block, respectively）, which agrees with the GPS observation data.

关键词： characteristic of Ms8.0 earthquakes Wenchuan earthquake second arc fault zone

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Prevalence of Cannabis Use around the World:A Systematic Review and Meta-Analysis,2000-2024

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China CDC weekly 2024年第25期6卷 597-604,I0013,I0014页

作者： Qianning Wang Zhen Qin Xing Xing He Zhu Zhongwei Jia National Institute of Health Data Science Center for Drug Abuse Prevention and ControlPeking UniversityBeijingChina School of Public Health Peking UniversityBeijingChina

This study aims to perform a systematic review and meta-analysis on the global prevalence of cannabis use to inform drug prevention strategies,policy-making,and resource *** study initially screened 177,843 studies published between January 1,2000,and January 15,2024,using peer-reviewed databases including Web of Science,PubMed,Scopus,Embase,and Cochrane ***,595 studies were identified for data extraction,and 39 of these were selected as country-representative *** among the selected studies was assessed using the chi-squared test and I2 statistic,while sensitivity analysis was conducted to evaluate the robustness of the *** prevalence of cannabis use varied between 0.42%and 43.90%across 33 European countries,1.40%to 38.12%across 15 North and South American countries,0.30%to 19.10%across 16 Asian countries,and 1.30%to 48.70%across 18 Oceania and African *** pooled prevalence of cannabis use was 12.0%[95%confidence interval(CI):10.0,14.3]in countries where cannabis is legalized,compared to 5.4%(95%CI:4.3,6.9)in non-legalized *** findings indicate that the prevalence of cannabis use has disproportionately increased in most countries with the implementation of medical or recreational cannabis legalization policies and relevant geographic *** efforts are needed to monitor newly cannabis-legalized countries and prevent initial use.

关键词： prevention legal initially

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Preparation of monodisperse agglomerated pellicul aranion-exchange resins compatible with HPLC solvents for ion chromatography

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Chinese Science Bulletin 1998年第8期43卷 702-703页

作者： Ning, Jun Kong, Fanzuo Li, Dianhai Du, Yuezong Research center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing China City monitor Station of Waste Water Exclusion Tianjin China

Discusses the preparation and properties of polymeric stationary phase for ion chromatography using monodisperse and highly cross-linked polymer beads by seed polymerization. Use of ion chromatography in neat water sample analysis; Microsuspension process for preparing the monosized nonporous DVB particles; Synthesis of the ion-exchange latex; Anion separation.

关键词： HPLC Preparation of monodisperse agglomerated pellicul aranion-exchange resins compatible with HPLC solvents for ion chromatography

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Identification of Early Warning Signals of Infectious Diseases in Hospitals by Integrating Clinical Treatment and Disease Prevention

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Current Medical Science 2024年第2期44卷 273-280页

作者： Lei ZHANG Min-ye LI Chen ZHI Min ZHU Hui MA Sixth Medical center Chinese PLA General HospitalBeijing100048China The Nursing Department Chinese PLA General HospitalBeijing 100853China

The global incidence of infectious diseases has increased in recent years,posing a significant threat to human *** typically serve as frontline institutions for detecting infectious ***,accurately identifying warning signals of infectious diseases in a timely manner,especially emerging infectious diseases,can be ***,there is a pressing need to integrate treatment and disease prevention data to conduct comprehensive analyses aimed at preventing and controlling infectious diseases within *** paper examines the role of medical data in the early identification of infectious diseases,explores early warning technologies for infectious disease recognition,and assesses monitoring and early warning mechanisms for infectious *** propose that hospitals adopt novel multidimensional early warning technologies to mine and analyze medical data from various systems,in compliance with national strategies to integrate clinical treatment and disease ***,hospitals should establish institution-specific,clinical-based early warning models for infectious diseases to actively monitor early signals and enhance preparedness for infectious disease prevention and control.

关键词： infectious disease disease prevention and control medical data warning signals

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X-Ray Source Classification Using Machine Learning:A Study with EP-WXT Pathfinder LEIA

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Research in Astronomy and Astrophysics 2024年第8期24卷 175-195页

作者： Xiaoxiong Zuo Yihan Tao Yuan Liu Yunfei Xu Wenda Zhang Haiwu Pan Hui Sun Zhen Zhang Chenzhou Cui Weimin Yuan National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China National Astronomical Data center Beijing 100101China

X-ray observations play a crucial role in time-domain *** Einstein Probe(EP),a recently launched X-ray astronomical satellite,emerges as a forefront player in the field of time-domain astronomy and high-energy *** a focus on systematic surveys in the soft X-ray band,EP aims to discover high-energy transients and monitor variable sources in the *** achieve these objectives,a quick and reliable classification of observed sources is *** this study,we developed a machine learning classifier for autonomous source classification using data from the EP-WXT Pathfinder—Lobster Eye Imager for Astronomy(LEIA)and EP-WXT *** proposed Random Forest classifier,built on selected features derived from light curves,energy spectra,and location information,achieves an accuracy of approximately 95%on EP simulation data and 98%on LEIA observational *** classifier is integrated into the LEIA data processing pipeline,serving as a tool for manual validation and rapid classification during *** paper presents an efficient method for the classification of X-ray sources based on single observations,along with implications of most effective features for the *** work facilitates rapid source classification for the EP mission and also provides valuable insights into feature selection and classification techniques for enhancing the efficiency and accuracy of X-ray source classification that can be adapted to other X-ray telescope data.

关键词： methods data analysis-X-rays binaries-stars variables general-X-rays bursts

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