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Improved forecasting via physics-guided machine learning as exemplified using“21·7”extreme rainfall event in Henan

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Science China Earth Sciences 2024年第5期67卷 1652-1674页

作者： Qi ZHONG Zhicha ZHANG Xiuping YAO Shaoyu HOU Shenming FU Yong CAO Linguo JING China Meteorological Administration Training Center Beijing 100081China State Key Laboratory of Severe weather Chinese Academy of Meteorological SciencesBeijing 100081China Zhejiang Meteorological Observatory Hangzhou 310017China hebei Provincial weather modification Center Shijiazhuang 050020China Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China National Meteorological Center Beijing 100081China School of Computer Science Chengdu University of Information TechnologyChengdu 610225China

As a natural disaster,extreme precipitation is among the most destructive and influential,but predicting its occurrence and evolution accurately is very challenging because of its rarity and *** the example of the“21·7”extreme precipitation event(17–21 July 2021)in Henan province,this study explores the potential of using physics-guided machine learning to improve the accuracy of forecasting the intensity and location of extreme *** physics-guided ways of embedding physical features,fusing physical model forecasts and revised loss function are used,i.e.,(1)analyzing the anomalous circulation and thermodynamical factors,(2)analyzing the multi-model forecast bias and the associated underlying reasons for it,and(3)using professional forecasting knowledge to design the loss function,and the corresponding results are used as input for machine learning to improve the forecasting *** results indicate that by learning the relationship between anomalous physical features and heavy precipitation,the forecasting of precipitation intensity is improved significantly,but the location is rarely adjusted and more false alarms *** reasons for this are as *** anomalous features used here mainly contain information about large-scale systems and factors which are consistent with the model precipitation deviation;moreover,the samples of extreme precipitation are sparse and so the algorithm used here is ***,by combining“good and different”multi models with machine learning,the advantages of each model are extracted and then the location of the precipitation center in the forecast is improved ***,by combining the appropriate anomalous features with multi-model fusion,an integrated improvement of the forecast of the rainfall intensity and location is ***,this study is a novel exploration to improve the refined forecasting of heavy precipitation with extreme intensity and high variability,

关键词： Extreme precipitation event Refined assessment Anomalous physical features Multi-model fusion Machine learning

Study on Quantitative Precipitation Estimation by Polarimetric Radar Using Deep Learning

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Advances in Atmospheric Sciences 2024年第6期41卷 1147-1160页

作者： Jiang HUANGFU Zhiqun HU Jiafeng ZHENG Lirong WANG Yongjie ZHU State Key Lab of Severe weather Chinese Academy of Meteorological SciencesBeijing 100081China Meteorological observatory of Jiangxi province Nanchang 330096China hebei Meteorological Disaster Prevention and Environmental Meteorological Center Shijiazhuang 050021China School of Atmospheric Sciences Chengdu University of Information TechnologyChengdu 610225China

Accurate radar quantitative precipitation estimation(QPE)plays an essential role in disaster prevention and *** this paper,two deep learning-based QPE networks including a single-parameter network and a multi-parameter network are ***,a self-defined loss function(SLF)is proposed during *** dataset includes Shijiazhuang S-band dual polarimetric radar(CINRAD/SAD)data and rain gauge data within the radar’s 100-km detection range during the flood season of 2021 in North *** that the specific propagation phase shift(KDP)has a roughly linear relationship with the precipitation intensity,KDP is set to 0.5°km^(-1 )as a threshold value to divide all the rain data(AR)into a heavy rain(HR)and light rain(LR)***,12 deep learning-based QPE models are trained according to the input radar parameters,the precipitation datasets,and whether an SLF was adopted,*** results suggest that the effects of QPE after distinguishing rainfall intensity are better than those without distinguishing,and the effects of using SLF are better than those that used MSE as a loss function.A Z-R relationship and a ZH-KDP-R synthesis method are compared with deep learning-based *** mean relative errors(MRE)of AR models using SLF are improved by 61.90%,51.21%,and 56.34%compared with the Z-R relational method,and by 38.63%,42.55%,and 47.49%compared with the synthesis ***,the models are further evaluated in three precipitation processes,which manifest that the deep learning-based models have significant advantages over the traditional empirical formula methods.

关键词： polarimetric radar quantitative precipitation estimation deep learning single-parameter network multi-parameter network

On the Shallowing of Antarctic Low-Level Temperature Inversions Projected by CESM-LE under RCP8.5

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Journal of Meteorological Research 2024年第3期38卷 586-599页

作者： Minghu DING Lin ZHANG Tingfeng DOU Yi HUANG Yingyan LUO Junmei LYU Cunde XIAO State Key Laboratory of Severe weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing100081China Key Laboratory of Meteorology and Ecological Environment of hebei province Hebei Provincial Institute of Meteorological SciencesShijiazhuang050021China College of Resources and Environment University of Chinese Academy of SciencesBeijing100049China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing100875China

Temperature inversions are frequently observed in the boundary layer and lower troposphere of polar *** variations of the low-level temperature inversions in these regions,especially the Antarctic,are still poorly *** to the scarcity of observations in the Antarctic,reanalysis data and numerical simulations are often used in the study of Antarctic climate *** on ERA-Interim,ERA5,JRA-55,and NCEP-NCAR reanalysis products,this study examines temporal and spatial variations of Antarctic inversion depth in austral autumn and winter during *** inversions are found to occur over the high plateau areas of the Antarctic *** on the Mann-Kendall test,ERA-Interim and ERA5 data reveal that the Antarctic inversion depth in austral autumn and winter increased during 1992-2007,roughly maintained afterwards,and then significantly decreased since around *** decrease trend is more obvious in the last two months of ***,JRA-55 better represents the spatial distribution of inversion depth,and ERA-Interim has better interannual *** Community Earth System Model Large Ensemble(CESM-LE)30-member simulations in 1979-2005 were first verified against JRA-55,showing reasonable consistency,and were then used to project the future changes of Antarctic low-level inversion depth over 2031-2050 under *** CESM-LE projection results reveal that the temperature inversion will shallow in the Antarctic at the end of the 21st century,and the decrease in depth in autumn will be more pronounced than that in *** particular,the temperature inversion will weaken over the ice-free ocean,while it will remain stable over the ice sheet,showing certain spatial heterogeneity and seasonal dependence on the underlying cryospheric surface *** addition,the decrease of inversion depth is found closely linked with the reduction in sea ice,suggesting the strong effect of global warming on the thermal structure change o

关键词： boundary layer temperature inversion Antarctic climate change Community Earth System Model Large Ensemble(CESM-LE)

Analysis of the Current Situation and Influencing Factors of Psychological Well-Being of Elderly People in the Community

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Journal of Clinical and Nursing Research 2024年第9期8卷 174-182页

作者： Ying Wang Zhijuan Hua Xiaopan Shi Yang Wang Jiaqi Fu Yanling Li Weihua Liu Department of Integrated Traditional Chinese and Western Medicine Affiliated Hospital of Hebei UniversityBaoding 071000Hebei ProvinceChina Quality Control office Affiliated Hospital of Hebei UniversityBaoding 071000Hebei ProvinceChina Department of Nursing Affiliated Hospital of Hebei UniversityBaoding 071000Hebei ProvinceChina Surgical Comprehensive Ward Affiliated Hospital of Hebei UniversityBaoding 071000Hebei ProvinceChina

Objective:To investigate the current psychological well-being of older people in the community and analyze its influencing ***:A total of 265 community-dwelling older adults aged 60 and above in Baoding City,hebei province,were selected through convenience sampling from November 2023 to March *** were surveyed using a general information questionnaire and a comprehensive well-being questionnaire,with results analyzed statistically using SPSS ***:Six dimensions of the psychological well-being scale for community older adults were identified:life vitality(P50=4.83),health concern(P50=4.6),self-worth(P50=5.6),friendly relationships(P50=5.33),altruistic behavior(P50=5.2),personality growth(P50=4.67),and comprehensive well-being(P50=161).Multivariate regression analysis showed that social isolation(β=-0.021,P<0.001),type of work(β=-0.142,P<0.001),chronic disease history(β=0.004,P<0.001),need for mobility aid(β=0.192,P<0.001),and monthly income(β=0.381,P<0.001)were factors influencing psychological ***:The psychological well-being of the elderly is slightly above moderate and requires *** factors such as reducing social isolation,addressing chronic disease history,and improving financial support could improve psychological well-being in older adults.

关键词： Community-dwelling older adults Psychological well-being Influencing factors

Observations of Cloud Condensation Nuclei in North China

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Acta meteorologica Sinica 2008年第1期22卷 97-106页

作者：石立新段英 weather modification office of hebei province

Using a DMT （Droplet Measurement Technologies） continuous flow streamwise thermal gradient cloud condensation nuclei （CCN） counter mounted on a Cheyenne IIIA aircraft, about 20 flights for aircraft mea- surements of CCN over North China were conducted in the autumn of 2005 and spring of 2006. According to the design for aircraft observation, the method of spiral ascent or descent in the troposphere was used for the vertical measurement of CCN, and some certain levels were chosen for horizontal measurement. The vertical distributions of CCN concentrations show that most CCN particles are concentrated in the low level of troposphere and CCN concentration decreased with height increasing. It suggests that the main source of CCN is from the surface. This result is consistent with former studies during 1983-1985 in China with a static thermal gradient CCN counter. The comparison of vertical observations between polluted rural area near Shijiazhuang and non-polluted rural area near Zhangjiakou shows that there is about five times difference in CCN concentration. But over two polluted cities, Shijiazhuang and Handan, there is no notable difference in CCN concentration. The horizontal flight measurements for penetrating the cumulus clouds experiment show the apparent decrease of CCN in clouds. It confirms that cloud has a definite consumptive effect on CCN particles because some CCN particles can form cloud droplets. The surface measurements of CCN in Shijiazhuang City were made during June-August 2005. The statistical CCN data show the great difference in concentration at the same supersaturation （S） in Shijiazhuang summertime. The minimum CCN concentrations were 584, 808, and 2431 cm-3, and the maximum concentrations were 9495, 16332, and 21812 cm-3 at S=0.1%, 0.3%, and 0.5%, respectively. CCN has a diurnal variation cycle. From 0600 BT, the concentration began to increase and reached the maximum at about noon. Then it generally decreased throughout the afternoon. The re

关键词： North China cloud condensation nuclei (CCN) observation

Scraping therapy for knee osteoarthritis: a systematic review and Meta-analysis

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Journal of Traditional Chinese Medicine 2024年第4期44卷 633-641页

作者： CHEN Dandan JIN Qianhong SHEN Yuanjuan WANG Qing DAI Zhengxiang School of Nursing Guangxi University of Chinese Medicine School of Nursing Nanjing University of Chinese Medicine General Surgery Department Jiangsu Province Hospital of Chinese Medicine Hospital Infection Control office Jiangsu Province Hospital of Chinese Medicine

OBJECTIVE: To systematically evaluate the efficacy of scraping therapy on knee osteoarthritis(KOA). METHODS: A computerized search was conducted in several databases, including PubMed, Web of Science, Cochrane Library, China National Knowledge Infrastructure Database, China Science and Technology Journal Database,Wanfang, and Chinese BioMedical Literature Database,from the establishment date of these databases to April 9,2023. Randomized controlled trials(RCTs) on scraping therapy for KOA were collected in accordance with the “Participants-Intervention-Control-Outcome-Study design”criteria. The methodological evaluation of the included studies was carried out using RoB 2.0, and Meta-analysis was conducted using RevMan. The Grades of Recommendations Assessment, Development and Evaluation(GRADE System) was applied to grade the quality of evidence. RESULTS: A total of 12 RCTs with 997 subjects were included in the Meta-analysis. Results indicated that compared with the control group, the scraping therapy treatment group exhibited increased Lysholm scores [mean difference(MD) = 4.96, 95% confidence intervals(CI)(3.18, 6.74), P < 0.000 01] and Hospital for Special Surgery scores [MD = 8.35, 95% CI(3.92, 12.78), P = 0.0002] and decreased visual analog scale scores [MD =-2.11, 95% CI(-3.79,-0.44), P = 0.01] and Western Ontario and McM aster University Osteoarthritis Index scores [MD =-6.77, 95% CI(-8.99,-4.56), P < 0.000 01)]. The quality of evidence obtained in this Meta-analysis was low according to the GRADE system. CONCLUSION: The available evidence suggests that scraping therapy may have certain clinical efficacy in the treatment of KOA. However, further high-quality RCTs are needed to confirm the findings.

关键词： Meta-analysis osteoarthritis, knee scraping systematic review

Antimicrobial Resistance Analysis and Whole-Genome Sequencing of Salmonella Isolates from Environmental Sewage — Guangzhou City, Guangdong province, China, 2022–2023

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China CDC weekly 2024年第13期6卷 254-260页

作者： Bihui Su Guanghong Du Shuiping Hou Zongqiu Chen Xiaoying Wu Gang He Jun Yuan Chaojun Xie Tuberculosis Management and Treatment Department Guangzhou Chest HospitalGuangzhou CityGuangdong ProvinceChina School of Public Health Guangzhou Medical UniversityGuangzhou CityGuangdong ProvinceChina Guangzhou Center for Disease Control and Prevention Guangzhou CityGuangdong ProvinceChina office of the Director Huadu District Center for Disease Control and PreventionGuangzhou CityGuangdong ProvinceChina

What is already known about this topic?S.1,4,[5],12:i:-and *** are emerging serotypes of Salmonella that require close monitoring for antimicrobial resistance and containment of their *** is added by this report?The study aimed to identify antimicrobial resistance genes(ARGs)in S.1,4,[5],12:i:-and *** strains isolated from environmental sewage in Guangzhou City,Guangdong province,China.A phylogenetic tree was constructed using single nucleotide polymorphism data to assess genetic relatedness among strains,offering insights for Salmonella infection outbreak investigations in the *** are the implications for public health practice?It is crucial to implement strategies,such as integrating different networks,to control the spread of drugresistant *** technologies must be utilized to disinfect sewage and eliminate *** food safety and proper sewage disinfection are essential to curb the dissemination of Salmonella.

关键词： Whole offering integrating

The Impact of New Regulations on Prevention and Control of E-Cigarettes on Adolescents in Middle Schools—A City in China,2022–2023

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China CDC weekly 2024年第14期6卷 289-293页

作者： Meng Lyu Wenlong Lu Lanhua Zou Jingfan Xiong Jie Yang Tobacco Control office Chinese Center for Disease Control and PreventionBeijingChina Shenzhen Center for Chronic Disease Control Shenzhen CityGuangdong ProvinceChina

What is already known about this topic?To protect the health of young people from the harmful impacts of electronic cigarettes(e-cigarettes),China has enacted various policies and regulations since *** of October 1,2022,the Electronic Cigarette Management Measures were put into *** prohibited the sale of flavored e-cigarettes,permitting only those of plain tobacco flavor to be *** is added by this report?The illegal market for flavored e-cigarettes,often disguised as milk tea cups,cola cans,and violent bear images,continues to *** is an increased need to bolster support for the prohibition of flavored e-cigarettes and enhance public awareness of associated *** are the implications for public health practice?To advance the health of China’s youth,it is crucial to improve the implementation and understanding of ecigarette policies and guidelines.

关键词： Middle Impact plain

The Protective Effects of Flavonoids from Scutellaria Baicalensis Georgi Stems and Leaves on Oligodendrocyte Damage Induced by Aβ_1-42

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Pharmacology & Pharmacy 2024年第1期15卷 1-13页

作者： Tangtang Song Yinhui Yao Yazhen Shang Institute of Traditional Chinese Medicine Chengde Medical College Chengde China hebei province Key Research office of Traditional Chinese Medicine against Dementia Hebei Province Key Laboratory of Traditional Chinese Medicine Research and Development Hebei Key Laboratory of Nerve Injury and Repair Chengde China

Aim: This study aimed to investigate the protective effects of flavonoids from the stem and leaves of Scutellaria baicalensis Georgi (SSFs) against Aβ1-42-induced oligodendrocytes (OL) damage. Methods: Immunofluorescence was used for the detection of myelin-associated glycoprotein (MAG), a characteristic protein of rat oligodendrocytes (OLN-93 cells). To evaluate the potential protective effects of SSFs on OLN-93 cells injured by Aβ1-42, an injury model was established by subjecting OLN-93 cells to Aβ1-42 exposed. Cell morphology was examined using an inverted microscope, while cell viability was assessed using the colorimetric method of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). Additionally, lactate dehydrogenase (LDH) was measured using the pyruvic acid reduction assay. The Ginkgo biloba leaf extract (GBE) injection was used as a positive control. Results: A total of >95% of the MAG immunofluorescence-positive cells were identified as oligodendrocytes. Gradually increasing concentrations of SSFs impaired the cells, and the maximum nondetrimental dose for OLN-93 cells was 75 mg/L. This study assessed the effects of SSFs on OLN-93 cells damaged by Aβ1-42. The results indicated that SSFs significantly improved OLN-93 cell morphological abnormal changes, increased the OLN-93 cell survival rate, and reduced LDH release. Conclusion: SSFs can alleviate Aβ1-42-induced damage of OL.

关键词： Flavonoids form the Stem and Leaves of Scutellaria baicalensis Georgi Aβ1-42 Oligodendrocytes Damage