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Geological and geochemical characteristics of the Baogudi Carlintype gold District(Southwest Guizhou, China) and their geological implications

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Acta Geochimica 2019年第4期38卷 587-609页

作者： Songtao Li Yong Xia Jianzhong Liu Zhuojun Xie Qinping Tan Yimeng Zhao Minghua Meng Lijin Tan Rong Nie Zepeng Wang Guanghong Zhou Haiyan Guo State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China University of Chinese Academy of Sciences Beijing 100049China No.105 Geological Team Guizhou Bureau of Geology and Mineral Exploration and DevelopmentGuiyang 550018China Bureau of Geology and Mineral Exploration and Development Guizhou Province Guiyang 550004China Guizhou Education University Guiyang 550018China School of Pharmacy Chengdu University of Traditional Chinese MedicineChengdu 611137China

The newly discovered Baogudi gold District is located in the southwestern Guizhou Province,China,where there are numerous Carlin-type gold deposits.To better understand the geological and geochemical characteristics of the Baogudi gold District,we carried out petrographic observations,elemental analyses,and fluid inclusion and isotopic composition studies.We also compared the results with those of typical Carlin-type gold deposits in southwestern Guizhou.Three mineralization stages,namely,the sedimentation diagenesis,hydrothermal(main-ore and late-ore substages),and supergene stages,were identified based on field and petrographic observations.The main-ore and late-ore stages correspond to Au and Sb mineralization,respectively,which are similar to typical Carlin-type mineralization.The mass transfer associated with alteration and mineralization shows that a significant amount of Au,As,Sb,Hg,Tl,Mo,and S were added to mineralized rocks during the main-ore stage.Remarkably,arsenic,Sb,and S were added to the mineralized rocks during the late-ore stage.Element migration indicates that the sulfidation process was responsible for ore formation.Four types of fluid inclusions were identified in ore-related quartz and fluorite.The main-ore stage fluids are characterized by an H2O–NaCl–CO2–CH4±N2system,with medium to low temperatures(180–260℃)and low salinity(0–9.08%NaCl equivalent).The late-ore stage fluids featured H2O–NaCl±CO2±CH4,with low temperature(120–200℃)and low salinity(0–7.48%Na Cl equivalent).The temperature,salinity,and CO2and CH4concentrations of ore-forming fluids decreased from the main-ore stage to the late-ore stage.The calculated δ^13C,d D,and δ^18O values of the ore-forming fluids range from-14.3 to-7.0%,-76 to-55.7%,and 4.5–15.0%,respectively.Late-ore-stage stibnite had δ^34S values ranging from-0.6 to 1.9%.These stable isotopic compositions indicate that the ore-forming fluids originated mainly from deep magmatic hydrothermal fluids,with minor contributions from strata.Collectively,the Baogudi metalloge

关键词： Elemental geochemistry Fluid inclusions Stable isotopes Carlin-type gold deposits Baogudi gold District Southwestern Guizhou

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Trends in the Prevalence of Births with Chromosomal Abnormalities—Haidian District,Beijing Municipality,China,2013–2022

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China CDC weekly 2023年第36期5卷 791-796页

作者： Shuangbo Xia Chao Meng Xiao Cheng Duoduo Wang Yaxian Wu Zhiwen Li Yuan Wei Jufen Liu Department of Epidemiology and Biostatistics School of Public HealthPeking UniversityBeijingChina Institute of Reproductive and Child Health/National Health Commission Key Laboratory of Reproductive Health Peking UniversityBeijingChina Department of Maternal Health Care Beijing Haidian Maternal and Child Health HospitalBeijingChina Department of Gynaecology and Obstetrics Peking University Third HospitalBeijingChina

Summary What is already known about this topic?The primary causes of early miscarriage and stillbirth are chromosomal abnormalities(CAs)whose prevalence has been observed to increase in recent years.What is added by this report?According to data received from a hospital-based birthdefect surveillance system in the Haidian District,Beijing,there was a significant increase in the prevalence of CAs along with most subtypes from 2013 to 2022.

关键词： Beijing District birth

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A method for extracting anomaly map of Au and As using combination of U-statistic and Euclidean distance methods in Susanvar District,Iran

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Journal of Central South University 2017年第11期24卷 2693-2704页

作者： Seyyed Saeed Ghannadpour Ardeshir Hezarkhani Mostafa Sharifzadeh Department of Mining & Metallurgical Engineering Amirkabir University of Technology (Tehran Polytechnic) Department of Mining Engineering and Metallurgical Engineering Western Australia School of MineCurtin University

Quantitative descriptions of geochemical patterns and providing geochemical anomaly map are important in applied geochemistry. Several statistical methodologies are presented in order to identify and separate geochemical anomalies. The U-statistic method is one of the most important structural methods and is a kind of weighted mean that surrounding points of samples are considered in U value determination. However, it is able to separate the different anomalies based on only one variable. The main aim of the presented study is development of this method in a multivariate mode. For this purpose, U-statistic method should be combined with a multivariate method which devotes a new value to each sample based on several variables. Therefore, at the first step, the optimum p is calculated in p-norm distance and then U-statistic method is applied on p-norm distance values of the samples because p-norm distance is calculated based on several variables. This method is a combination of efficient U-statistic method and p-norm distance and is used for the first time in this research. Results show that p-norm distance of p=2(Euclidean distance) in the case of a fact that Au and As can be considered optimized p-norm distance with the lowest error. The samples indicated by the combination of these methods as anomalous are more regular, less dispersed and more accurate than using just the U-statistic or other nonstructural methods such as Mahalanobis distance. Also it was observed that the combination results are closely associated with the defined Au ore indication within the studied area. Finally, univariate and bivariate geochemical anomaly maps are provided for Au and As, which have been respectively prepared using U-statistic and its combination with Euclidean distance method.

关键词： mineral anomaly Susanvar District U-statistic method Euclidean distance bivariate anomaly map

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Genesis of the Huoshenmiao Mo deposit in the Luanchuan ore District, China: Constraints from geochronology, ?uid inclusion, and H-O-Sisotopes

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Geoscience Frontiers 2019年第1期10卷 331-349页

作者： Sai Wang Bing Li Xingkang Zhang Peng Wang Weiwei Chao Huishou Ye Yongqiang Yang Key Laboratory of Marine Sedimentology and Environmental Geology First Institute of Oceanography State Oceanic Administration Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology Hebei Institute of Geological Survey School of Earth Sciences and Resources China University of Geosciences MLR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral Resources CAGS

The Huoshenmiao δeposit is Mo skarn δeposit, located in the western part of the Luanchuan ore δistrict.Mineralization process can be δivided into a skarn and a quartz-sulfide episodes with six stages: prograde(I), retrograde(II), quartz-K-feldspar(III), quartz-molybdenite(IV), quartz-pyrite(V), and quartzcalcite(VI). A combined study of geochronology, fluid inclusion(FI), and stable isotopes was conducted to constrain the mineralization age, source of ore materials, as well as the origin and evolution of the ore-forming fluids. Molybdenite Ree Os δating indicates that the δeposit was formed in the Late Jurassic(~145 Ma). The δ^(34)S values of sulfides range from 3.0‰ to 7.1‰, implying that the ore materials in the δeposit are magmatic in origin. Three types and six subtypes of FIs are δistinguished, namely, aqueous two-phase(W_1-and W_2-type), δaughter mineral-bearing multiphase(S_1-and S_2-type), and CO_2-bearing three-phase(C_1-and C_2-type). In stages I and II, the W_1-type FIs δisplay homogenization temperatures(Th) from 496°C to >600°C, with salinities of 14.9-18.3 wt.% NaCl eqv. The FIs in stages III, IV and early stage V composed of coeval S-, C-and W-types, respectively homogenize at similar Th, suggesting the occurrence of boiling. The W1-type FIs in late stage V and stage VI, yield Th of 102-406°C and salinities of 0-4.7 wt.% NaCl eqv. The δD_(H_2O)and δ^(18) O(H_2O)values of the ore-forming fluids in quartz-sulfide episode vary from-112‰ to-76‰, and 11.0‰ to 1.0‰, respectively. All these above observations reveal that the early ore-forming fluids are magmatic in origin, and characterized by high temperature and moderate to high salinity, and gradually evolve to low temperature, low salinity meteoric water. The Huoshenmiao Mo δeposit is associated with the magmatism event induced by the protracted subduction of the Izanagi plate beneath the eastern China continent. The δecrease in temperature, salinity and f(O_2), as well as change of p H δue to boiling and fluid-rock interaction, are the main factors c

关键词： Molybdenite Re-Os age Fluid inclusion H-O-S isotopes Huoshenmiao Mo deposit Luanchuan ore District

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Genetic Types and Metallogenic Model for the Polymetallic Copper–Gold Deposits in the Tongling Ore District, Anhui Province, Eastern China

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Acta Geologica Sinica(English Edition) 2019年第1期93卷 88-110页

作者： FU Zhongyang XU Xiaochun HE Jun FAN Ziliang XIE Qiaoqin DU Jianguo CHEN Fang School of Resources and Environmental Engineering Hefei University of Technology Geological Survey of Anhui Province

The Tongling ore District is one of the most economically important ore areas in the Middle–Lower Yangtze River Metallogenic Belt, eastern China. It contains hundreds of polymetallic copper–gold deposits and occurrences. Those deposits are mainly clustered(from west to east) within the Tongguanshan, Shizishan, Xinqiao, Fenghuangshan, and Shatanjiao orefields. Until recently, the majority of these deposits were thought to be skarn-or porphyry–skarn-type deposits; however there have been recent discoveries of numerous vein-type Au, Ag, and Pb-Zn deposits that do not fall into either of these categories. This indicates that there is some uncertainty over this classification. Here, we present the results of several systematic geological studies of representative deposits in the Tongling ore District. From investigation of the ore-controlling structures, lithology of the host rock, mineral assemblages, and the characteristics of the mineralization and alteration within these deposits, three genetic types of deposits(skarn-, porphyry-, and vein-type deposits) have been identified. The spatial and temporal relationships between the orebodies and Yanshanian intrusions combined with the sources of the ore-forming fluids and metals, as well as the geodynamic setting of this ore District, indicate that all three deposit types are genetically related each other and constitute a magmatic–hydrothermal system. This study outlines a model that relates the polymetallic copper–gold porphyry-, skarn-, and vein-type deposits within the Tongling ore District. This model provides a theoretical basis to guide exploration for deep-seated and concealed porphyry-type Cu(–Mo, –Au) deposits as well as shallow vein-type Au, Ag, and Pb–Zn deposits in this area and elsewhere.

关键词： polymetallic copper–gold deposits genetic types metallogenic model magmatic–hydrothermal system Tongling ore District Anhui Province

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COVID-19 vaccine hesitancy and related factors among primary healthcare workers in a District of Istanbul:a cross-sectional study from Turkey

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Family Medicine and Community Health 2022年第2期10卷 32-39页

作者： Haticeİkiışık Mehmet Akif Sezerol Yusuf Taşçı Işıl Maral Department of Public Health Faculty of MedicineIstanbul Medeniyet UniversityIstanbulTurkey Public Health Department Institute of Health SciencesIstanbul UniversityIstanbulTurkey

Objectives This study aimed to determine the COVID-19 risk perceptions,vaccination intentions and predictive factors of family physicians and family healthcare staff working in primary care inÜsküdar.Design A cross-sectional study was performed using an online questionnaire to determine the demographic and general characteristics of the participants and their willingness to be vaccinated.Setting An online questionnaire was applied to family physicians and family health workers working in primary care family health centres inÜsküdar between 25 and 29 December 2020.Multivariate analysis was performed to identify independent predictors of the willingness of individuals to be vaccinated.Participants Out of 323 health workers working in 44 family health centres in the District,a total of 276 health workers were reached,including 126 physicians(n=158,79.7%)and 150 midwives/nurses(n=165,90.9%)(response rate 85.4%).Results 50.4%(n=139)of the healthcare workers were willing to have the COVID-19 vaccine,29%(n=80)were undecided and 20.7%(n=57)refused the vaccine.The rate of acceptance to be vaccinated was higher in physicians,in men and in those who had not received a seasonal influenza vaccination regularly each year.Conclusions Half of the primary healthcare workers,one of the high-risk groups in the pandemic,were hesitant or refused to be vaccinated for COVID-19.Knowing the factors affecting the vaccine acceptance rates of healthcare professionals can be considered one of the most strategic moves in reaching the target of high community vaccination rates.For evidence-based planning in vaccination studies,there is a need to investigate the reasons for COVID-19 vaccine acceptance by healthcare workers at all levels.

关键词： nurse workers District

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Optimization of Agricultural Industrial Structure in Changping District of Beijing Based on Grey Relational Analysis

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Asian Agricultural Research 2024年第4期16卷 3-7页

作者： Haosong LI Rao CHEN College of Economics and Management Beijing University of AgricultureBeijing Research Center of Rural RevitalizationBeijing 102206China

In the economic development of Beijing,although the share of the total amount of agricultural industry in the overall economy is relatively low,it has an important impact on the daily life of residents,social stability and the development of other industries.Changping District,as an important agricultural production base of Beijing,its agricultural development has an indispensable strategic significance for the stability and growth of the entire regional economy.Therefore,it is very important to study the structure of agricultural industry in Changping District.Based on the detailed analysis of the agricultural industrial structure of Changping District,this paper uses the grey relation theory to analyze the different industries in the agricultural industrial structure of Changping District,including planting,forestry,animal husbandry,fishery and agricultural,forestry,service industries,in order to reveal the impact of these industries on the agricultural industrial structure of Changping District.Through this study,it comes up with specific and feasible suggestions for the optimization of agricultural industrial structure in Changping District,and provides valuable reference for the agricultural development of other areas in Beijing.

关键词： Grey relation theory Changping District Agricultural industrial structure

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A study on traditional medicinal plants of uthapuram,Madurai District,Tamilnadu,south India

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Asian Pacific Journal of Tropical Biomedicine 2013年第12期3卷 975-979页

作者： Balayogan Sivasankari Subburaj Pitchaimani Marimuthu Anandharaj Department of Biology Gandhigram Rural Institute-Deemed University

Objective:To record the medicinal plants of Uthapuram Village,Madurai District,Tamilnadu,South India for the first time and the usage of these medicinal plants to remediate the diseases among the peoples.Methods:Explorative field trips were made to the village for about twelve months from April 2012to May 2013 to survey the medicinal plants and collect the information from the villagers.Results:From this study 52 species of valuable medicinal plants belonging to 36 families were recorded and their ethnomedicinal values were collected from the village peoples.Conclusion:This study focuses the importance,utilization and conservation of the medicinal plants among the people.

关键词： Traditional medicine Medicinal plants Uthapuram Madurai District

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Ethnobotanical survey of folklore plants used in treatment of snakebite in Paschim Medinipur District,West Bengal

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Asian Pacific Journal of Tropical Biomedicine 2014年第5期4卷 416-420页

作者： Sumana Sarkhel Department of Human Physiology with Community Health Vidyasagar University

Objective:To investigate and collect information from traditional health healers/tribal communities on the use of medicinal plants for treatment of snakebite.Methods:The ethno-medicinal study was conducted in 8 villages of the Paschim Medinipur District of West Bengal in 2012-2013 through questionnaire and personal interviews.Following the method of Martin,information about medicinal plants used in snake bite,precise plant parts used,methods of treatment and administration was enquired from the tribal communities(Santhals,Mundas,Lodhas,Bhumijs,Oram Kherias) of the region.Results:The present study enumerates 20 ethnomedicinal plant species belonging to 16 families used by the tribal communities and medicinal healers of Paschim Medinipur District,West Bengal in treatment of snakebite.Each plant species has been listed alphabetically according to its botanical name,family,vernacular name,part(s) used,mode of preparation/administration.Conclusions:The importance of traditional medicinal system among the tribal communities of Paschim Medinipur District of West Bengal has been highlighted in the present study.

关键词： Traditional medicinal system Snakebite Paschim Medinipur District

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Analysis of Micro Thermal Environment for Residential District Planning

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湖南大学学报（自然科学版） 2009年第S1期36卷 51-54页

作者： ZHANG Wei-jie1,QI Jing2,JIN Wen2(1.Institute of Urban Construction,Hebei University of Engineering,Handan,Hebei 056038,China 2.School of Architecture,Hebei University of Engineering,Handan,Hebei 056038,China) Institute of Urban Construction Hebei University of Engineering Handan 056038 China School of Architecture Hebei University of Engineering Handan 056038 China

This paper focused on residential District planning process.Using GIS and SketchUp software,a common digital relief map model of a residential District was created,and the air distribution(both velocity and temperature)within this residential District was established by CFD simulation.So,the velocity and temperature of the air at any location within the residential District,as well as the worse flow area and overheat area can be clearly presented.An index of micro thermal environment for the air distribution evaluation was established.Depending on a certain residential District planning model,from the air parameters of the micro environment at any location within the residential District,such as air velocity and air temperature,the index of micro thermal environment was obtained by certain principles and data processing process.By this index,the residential District planning scheme was evaluated corresponding to the thermal characteristics of the residential District.If this index is not good enough or unsatisfied,the residential District planning idea and process can be changed or improved accordingly in order to get a better thermal characteristics of the residential District judged by the established evaluation index system.

关键词： residential District planning micro thermal environment micro thermal environmental index CFD SketchUp

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