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Identifying the Hydrochemical Characteristics,Genetic Mechanisms and Potential Human Health Risks of Fluoride and Nitrate Enriched Groundwater in the Tongzhou District,Beijing,North China
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作者 ZHANG Shouchuan LIU Kai +2 位作者 MA Yan WANG Luyao SUN Junliang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第2期468-476,共9页
Fluoride and nitrate enriched groundwater are potential threats to the safety of the groundwater supply that may cause significant effects on human health and public safety,especially in aggregated population areas an... Fluoride and nitrate enriched groundwater are potential threats to the safety of the groundwater supply that may cause significant effects on human health and public safety,especially in aggregated population areas and economic hubs.This study focuses on the high F^(−)and NO_(3)^(−)concentration groundwater in Tongzhou District,Beijing,North China.A total of 36 groundwater samples were collected to analyze the hydrochemical characteristics,elucidate genetic mechanisms and evaluate the potential human health risks.The results of the analysis indicate:Firstly,most of the groundwater samples are characterized by Mg-HCO_(3) and Na-HCO_(3) with the pH ranging from 7.19 to 8.28 and TDS with a large variation across the range 471-2337 mg/L.The NO_(3)^(−)concentration in 38.89%groundwater samples and the F^(−)concentration in 66.67%groundwater samples exceed the permissible limited value.Secondly,F^(−)in groundwater originates predominantly from water-rock interactions and the fluorite dissolution,which is also regulated by cation exchange,competitive adsorption of HCO_(3)−and an alkaline environment.Thirdly,the effect of sewage disposal and agricultural activities have a significant effect on high NO3-concentration,while the high F^(−)concentration is less influenced by anthropogenic activity.The alkaline environment favors nitrification,thus being conducive to the production of NO_(3)^(−).Finally,the health risk assessment is evaluated for different population groups.The results indicate that high NO_(3)^(−)and F^(−)concentration in groundwater would have the largest threat to children’s health.The findings of this study could contribute to the provision of a scientific basis for groundwater supply policy formulation relating to public health in Tongzhou District. 展开更多
关键词 fluoride concentration nitrate pollution genetic mechanism health risk assessment tongzhou district
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PMF+双门限Tong检测的北斗B1I信号捕获算法
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作者 刁彦华 徐亚丽 +1 位作者 王晓君 刘昊昱 《通信与信息技术》 2024年第2期1-5,共5页
针对传统Tong检测算法检测时间长、漏警概率大的问题,提出将PMF+双门限Tong检测算法应用于北斗B1I信号的捕获中。首先,将射频前端模块处理得到的中频信号下变频至基带,对基带信号进行降速等预处理;然后,利用部分匹配滤波(PMF)算法计算... 针对传统Tong检测算法检测时间长、漏警概率大的问题,提出将PMF+双门限Tong检测算法应用于北斗B1I信号的捕获中。首先,将射频前端模块处理得到的中频信号下变频至基带,对基带信号进行降速等预处理;然后,利用部分匹配滤波(PMF)算法计算相关值,通过PMF算法将数据信号分成几个均等片段,对每一段信号都分别计算相关值,会出现三组具有同相位的相关结果;最后,利用双门限Tong检测算法对PMF算法计算得到的相关结果检测,达到捕获B1I信号的目的。仿真结果表明,利用该算法捕获北斗B1I信号,有效提高了捕获时的检测概率并缩短了检测时间,提高了捕获B1I信号的速度。 展开更多
关键词 B1I信号 匹配滤波 双门限tong检测 信号捕获
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Effects of drip and flood irrigation on carbon dioxide exchange and crop growth in the maize ecosystem in the Hetao Irrigation District,China
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作者 LI Chaoqun HAN Wenting PENG Manman 《Journal of Arid Land》 SCIE CSCD 2024年第2期282-297,共16页
Drip irrigation and flood irrigation are major irrigation methods for maize crops in the Hetao Irrigation District,Inner Mongolia Autonomous Region,China.This research delves into the effects of these irrigation metho... Drip irrigation and flood irrigation are major irrigation methods for maize crops in the Hetao Irrigation District,Inner Mongolia Autonomous Region,China.This research delves into the effects of these irrigation methods on carbon dioxide(CO_(2))exchange and crop growth in this region.The experimental site was divided into drip and flood irrigation zones.The irrigation schedules of this study aligned with the local commonly used irrigation schedule.We employed a developed chamber system to measure the diurnal CO_(2)exchange of maize plants during various growth stages under both drip and flood irrigation methods.From May to September in 2020 and 2021,two sets of repeated experiments were conducted.In each experiment,a total of nine measurements of CO_(2)exchange were performed to obtain carbon exchange data at different growth stages of maize crop.During each CO_(2)exchange measurement event,CO_(2)flux data were collected every two hours over a day-long period to capture the diurnal variations in CO_(2)exchange.During each CO_(2)exchange measurement event,the biological parameters(aboveground biomass and crop growth rate)of maize and environmental parameters(including air humidity,air temperature,precipitation,soil water content,and photosynthetically active radiation)were measured.The results indicated a V-shaped trend in net ecosystem CO_(2)exchange in daytime,reducing slowly at night,while the net assimilation rate(net primary productivity)exhibited a contrasting trend.Notably,compared with flood irrigation,drip irrigation demonstrated significantly higher average daily soil CO_(2)emission and greater average daily CO_(2)absorption by maize plants.Consequently,within the maize ecosystem,drip irrigation appeared more conducive to absorbing atmospheric CO_(2).Furthermore,drip irrigation demonstrated a faster crop growth rate and increased aboveground biomass compared with flood irrigation.A strong linear relationship existed between leaf area index and light utilization efficiency,irrespective of the irrigation method.Notably,drip irrigation displayed superior light use efficiency compared with flood irrigation.The final yield results corroborated these findings,indicating that drip irrigation yielded higher harvest index and overall yield than flood irrigation.The results of this study provide a basis for the selection of optimal irrigation methods commonly used in the Hetao Irrigation District.This research also serves as a reference for future irrigation studies that consider measurements of both carbon emissions and yield simultaneously. 展开更多
关键词 carbon dioxide exchange maize growth drip irrigation harvest index net primary productivity Hetao Irrigation district
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Optimization of Agricultural Industrial Structure in Changping District of Beijing Based on Grey Relational Analysis
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作者 Haosong LI Rao CHEN 《Asian Agricultural Research》 2024年第4期3-7,共5页
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 stabilit... 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. 展开更多
关键词 GREY RELATION theory Changping district AGRICULTURAL INDUSTRIAL structure
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Genetic Types and Metallogenic Model for the Polymetallic Copper–Gold Deposits in the Tongling Ore District, Anhui Province, Eastern China 被引量:6
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作者 FU Zhongyang XU Xiaochun +4 位作者 HE Jun FAN Ziliang XIE Qiaoqin DU Jianguo CHEN Fang 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2019年第1期88-110,共23页
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 occurre... 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. 展开更多
关键词 POLYMETALLIC copper–gold deposits genetic types METALLOGENIC model magmatic–hydrothermal system tongLING ore district Anhui Province
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Geochemistry and Geochronology of the Causative Intrusion and a New Genetic Model Study of the Yaojialing Polymetallic Skarn Deposit, Tongling District, China 被引量:1
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作者 XIONG Yanyun ZHOU Taofa +2 位作者 FAN Yu CHEN Jing LIU Jun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2020年第6期1997-2011,共15页
The Yaojialing deposit is the first large-scale Zn-Au-Cu polymetallic skarn deposit located in the Shatanjiao ore field of the Tongling area in the Middle-Lower Yangtze belt.It has distinct metallogenic characteristic... The Yaojialing deposit is the first large-scale Zn-Au-Cu polymetallic skarn deposit located in the Shatanjiao ore field of the Tongling area in the Middle-Lower Yangtze belt.It has distinct metallogenic characteristics and is clearly different from the known skarn Cu-Au deposits in the Tongling area and the Middle-Lower Yangtze belt.Previous studies of the Yaojialing deposit have included rock geochemistry,alteration and mineralization characteristics,as well as metallogenesis and metallogenic models.However,there are still numerous problems concerning the coexistence of multiple elements,metallogenetic specialization of the magma and the metallogenic model.In this study,using the latest production exploration work on the deposit,we investigated the Yaojialing deposit including its geological characteristics,petrography,LA-ICP MS zircon U-Pb dating and whole rock geochemistry.Two kinds of magmatic rocks have been distinguished for the first time in the deposit,amongst which the granodiorite porphyry exposed on the surface of the mining area,which is the host rock of the veined lead-zinc ore body,is the wall-rock intrusion;and the deep concealed quartz monzonite porphyry is the causative intrusion,the distribution of orebodies and wall-rock alteration characteristics showing regular zoning around the quartz monzonite porphyry.The^(206)Pb/^(238)U weighted average age of the granodiorite porphyry is 140.2±1.0 Ma(MSWD=0.85,n=13)by LA-ICP MS zircon U-Pb dating,while the quartz monzonite porphyry is 138.9±1.2 Ma(MSWD=0.60,n=16),which is consistent with petrographic evidence.The geochemical characteristics show that the quartz monzonite porphyry is a high-K calc-alkaline series peraluminous rock.The trace element characteristics show that the quartz monzonite porphyry is enriched in LILE such as K,Rb,Sr,Ba and LREE,yet depleted in HFSE such as Nb,Ta,P and Ti.The Yaojialing deposit shows the mineralization characteristics of proximal skarn and distal skarn,having the common characteristics of'multi-storey'and'Trinity'metallogenic models. 展开更多
关键词 LA-ICP MS zircon U-Pb dating GEOCHEMISTRY Yaojialing deposit tongling district
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Viability of high-density resistivity method for evaluating mountain slope stability in Erdaojiang District,Tonghua City,China 被引量:2
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作者 XIN Zhonghua HAN Jiangtao +1 位作者 LI Zhuoyang LIU Lijia 《Global Geology》 2020年第4期225-233,共9页
The authors employ the high-density resistivity method to image the subsurface structure of a mountain in Erdaojiang District,Tonghua City,Jilin Province,China,to evaluate the potential risk of slope failure on surrou... The authors employ the high-density resistivity method to image the subsurface structure of a mountain in Erdaojiang District,Tonghua City,Jilin Province,China,to evaluate the potential risk of slope failure on surrounding residential areas and infrastructure,and identify a shallow fault that extends across the center of the mountain and is perpendicular to the mountain slope and accurately locate the spatial position and depth of another fault on the southern side of the mountain.The results provide an important basis for evaluating mountain slope stability.This study also demonstrates that the high-density resistivity method is effective for detecting mountain faults. 展开更多
关键词 Erdaojiang district tonghua City Jilin Province high-density resistivity method electrical resistivity structure mountain faults
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Public Effective Dose Assessment Using Gross Alpha and Beta Radioactivity Levels of Tap Drinking Water in the District of Abidjan, Cote d’Ivoire
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作者 Ponaho Claude Kezo Issa Konate Tekpo Paul Dali 《Journal of Environmental Protection》 CAS 2023年第3期127-138,共12页
In order to assess public effective dose due to gross alpha and beta in water, 43 tap water samples were collected from different areas in the District of Abidjan. Using the low background Gas-less Automatic Alpha/Bet... In order to assess public effective dose due to gross alpha and beta in water, 43 tap water samples were collected from different areas in the District of Abidjan. Using the low background Gas-less Automatic Alpha/Beta counting system (Canberra iMatic<sup>TM</sup>) for analysis, the gross alpha and beta concentrations found varied from 0.001 ± 0.002 to 0.063 ± 0.050 Bq/l with an average of 0.013 ± 0.012 Bq/l and from 0.067 ± 0.080 to 0.320 ± 0.120 Bq/l with an average of 0.174 ± 0.076 Bq/l, respectively in samples. The public effective dose assessment showed values of dose to ingestion of alpha and beta emitter radionuclides lower than the recommended value of dose for drinking water 0.1 mSv/y, except in 30% of the samples. These results show the need for additional studies to be conducted in order to clarify the hazardousness of these water samples. However, this study still remains important because it has provided necessary data for future tap water quality monitoring studies in the District of Abidjan. 展开更多
关键词 Gross Alpha and Beta Concentration Tap Water Effective Dose district of Abidjan
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Acceptability of Ambulatory Surgical Services and Its Predictors among Residents of Budondo Sub-County—Jinja District, Uganda
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作者 Anna Turumanya Kalumuna 《Surgical Science》 2023年第3期170-191,共22页
Background: 25% of all people requiring surgical care are not able to access it due to its high cost. These people stand a high risk of preventable severe morbidity and mortality due to poor prognosis of surgically co... Background: 25% of all people requiring surgical care are not able to access it due to its high cost. These people stand a high risk of preventable severe morbidity and mortality due to poor prognosis of surgically correctable illnesses. Ambulatory surgical care services are significantly cheaper than orthodox surgical care and have become very relevant in this time and age where health conditions that can only be treated with surgical intervention are on the rise. The acceptability of ambulatory surgical care services will determine how this model increases universal health coverage. Objective: To assess the acceptability of ambulatory surgical services and its predictors among residents of Budondo Sub-County—Jinja district. Methods: The study was cross-sectional targeting 371 household heads in Budondo Sub-County, which was stratified by parish, with villages in each randomly sampled. Systematic random sampling was used to sample households and households therein were purposively sampled. Structured interviews and questionnaires were the data collection techniques, and data was analyzed in SPSS version 25 using descriptive statistics and a binomial logit model. Results: The level of acceptability of ambulatory surgical care services among residents of Budondo Sub-County was found to be near-universal, at 96.5%. The odds of accepting ambulatory surgical care were least among household heads who agreed that surgery done in a hospital would be cheaper than surgery done at community level (aOR = 0.174 [CI = 0.055 - 0.553]), those who had health insurance (aOR = 0.105 [95% CI = 0.030 - 0.371]), and household heads who were covered with private health insurance (aOR = 0.078 [95% CI = 0.008 - 0.792]). Acceptability of ASC was higher among household heads who agreed that they would trust ambulatory surgical centers with their life were more likely to accept ambulatory surgical care (aOR = 1.124, [95% CI = 1.122 - 3.218], P = 0.000), and household heads from households that had less than five members with surgery history were twice as likely to accept ambulatory surgical care (aOR = 2.431 [95% CI = 1.122 - 5.898], P = 0.000). Conclusion: Acceptability of ambulatory surgical care services among residents of Budondo Sub-County is high, and near-universal. It is mainly predicted by intrapersonal correlates and to a small extent by socio-demographic characteristics, with the implication that the administration of Global Surgical Initiatives in Kyabirwa ought to focus on modifying or uphold the intrapersonal characteristics found to be antagonists and protagonists of acceptability, respectively. 展开更多
关键词 ACCEPTABILITY Ambulatory Surgery PREDICTORS Jinja district
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Factors Affecting the Adoption of Agricultural Mechanization Technologies by Women Farmers in the Karaga District of Ghana
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作者 Emelia Guo Mamudu A. Akudugu 《Agricultural Sciences》 2023年第9期1238-1248,共11页
Labour-saving or mechanization technologies have become the driving force behind modern agriculture, yet adoption of these technologies remains low in many parts of the developing world, particularly among female farm... Labour-saving or mechanization technologies have become the driving force behind modern agriculture, yet adoption of these technologies remains low in many parts of the developing world, particularly among female farmers in Ghana. This study aims to investigate the factors that hinder the adoption of agricultural mechanization technologies by female farmers in the Karaga District of the Northern Region of Ghana. This region is known for its large agricultural lands and significant role in commercial farming. The research was conducted using qualitative research methodology and involved interviewing 60 female farmers using an interview guide. The principle of sample saturation was used, meaning that further interviews were deemed unnecessary after the 60th interview. The results showed that low adoption of agricultural mechanization technologies is due to poor access to commercial lands, gender biases, lack of access to credit, and poor awareness about the benefits of these technologies. In conclusion, the low adoption of agricultural mechanization technologies is preventing women farmers in the Karaga District and elsewhere in Ghana from fully participating in commercial agricultural production. It is recommended that gender biases and cultural stereotypes be addressed to improve women farmers’ access to lands and credit, which will facilitate the adoption of mechanization technologies and lead to improved agricultural production. 展开更多
关键词 ADOPTION Agricultural Mechanization Women Farmers Ghana Karaga district
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The Prevalence Outcome and Associated Factors of Teenage Pregnancy in the Bamenda Health District
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作者 Takang William Ako Dobgima Walter Pisoh +5 位作者 Nguemaim Flore Kwangfis Richard Nemline Achuo Ascensius Mforteh Tameh Theodore Boten Bouyom Pierre Merlin Robert J.I. Leke 《Open Journal of Obstetrics and Gynecology》 2023年第7期1163-1183,共21页
Teenage pregnancy is a common public health problem worldwide because teenagers in general are ill-prepared to deal with the burden of pregnancy. Sub-Saharan Africa has the highest burden of teenage pregnancy precisel... Teenage pregnancy is a common public health problem worldwide because teenagers in general are ill-prepared to deal with the burden of pregnancy. Sub-Saharan Africa has the highest burden of teenage pregnancy precisely in the west and central Africa;in Cameroon, about 12% of all births are to teenage mothers. Complications from pregnancy and childbirth are the leading cause of death among girls aged 15 to 19. Though the trend of teenage pregnancy tends to decrease in most parts of the world, this is not the case in our setting. The main aim of this study was to determine the prevalence, outcomes and the associated factors of teenage pregnancy in the Bamenda Health District (BHD). Materials and Method: This was a hospital-based cross-sectional descriptive and analytic study carried out at the maternity and postnatal units of the Bamenda Regional Hospital and the Nkwen Medicalised Health Center. A consecutive non-probabilistic sampling technique was used to recruit participants. A pretested questionnaire was used to collect information from the participant. Data was analysed using the software SPSS version 23. Bivariate logistic regression was used to test for associations. Statistical significance was set at p-value less than 0.05. Result: A total of 325 participants were recruited of which 44 were teenagers. The mean age of the participants was 25.02 ± 0.257 years. The mean age of teenagers was 17.49 ± 0.63 years, and mean adult age was 28.43 ± 5.64 years. The youngest participant was 15 years. Teenagers were significantly more likely to prematurity (OR = 0.14;95% CI = 0.06 - 0.31;PV = 0.001), Low birth weight among teenagers (OR = 0.077;95% CI = 0.03 - 0.21;PV = 0.001), Still birth;OR = 0.07;95% CI = 0.01 - 0.86;PV = 0.03) Neonatal admission also high among teenagers (OR = 0.172, 95% CI = 0.08 - 0.39, PV = 0.001) compared to the babies of their adult counterpart. The rate of caesarean section and episiotomy was high among adult deliveries (21.7%). Conclusion: There is a high prevalence of teenage pregnancy (13.54%) in the Bamenda Health District. prematurity was independently associated with teenage pregnancy. perineal tears were the most common maternal outcome of teenage pregnancy. Adolescents/teenagers in rural areas, having a low level of income, and low level of education were associated with high level of teenage pregnancy. 展开更多
关键词 Adolescent/Teenage Pregnancy PREVALENCE OUTCOMES Associated Factors Bamenda Health district
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Optimization of Green Space Plant Configuration in Residential Areas of Chongqing Central Business District Based on Green Plot Ratio—A Case Study of Xuhui City Residential Community
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作者 Xianteng Ma Tinghan Yan +2 位作者 Yangyang Qin Haoli Wang Yifan Yan 《Journal of Geoscience and Environment Protection》 2023年第6期37-49,共13页
The current urban green space construction was guided by a two-dimensional index evaluation system, resulting in weak ecological benefits of green space. Green plot ratio (GPR), as a three-dimensional indicator, can c... The current urban green space construction was guided by a two-dimensional index evaluation system, resulting in weak ecological benefits of green space. Green plot ratio (GPR), as a three-dimensional indicator, can characterize the ecological benefits of green areas and the ability of green areas to participate in the operation and regulation of urban ecosystems. As an important component of urban green space, the GPR index was added to the two-dimensional index evaluation system to optimize the green space, which can promote the development of low-carbon, healthy and ecological green space. Based on the research of 22 residential districts in the central city of Chongqing, the Leaf area index (LAI) index of common native garden plants in Chongqing was formed to improve the accuracy of green capacity index measurement in Chongqing. The study also took the residential community of Sunrise City in Banan District of Chongqing as an example, and carried out the optimization design practice from four types of residential community green areas: green areas next to houses, road green areas, concentrated green areas, and green areas attached to public service facilities. 展开更多
关键词 Urban Greening Ecological Benefits Residential district Leaf Area Index Plant Selection
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Study on the mechanism of effect of Daodi Tongguan Decoction on rats with premature ovarian failure
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作者 LONG Yun-xia ZHONG Yi-hui +5 位作者 WU Yuan-yuan CHEN Qiu-jin DU Li ZHENG Hong LI Yin-ying LUO Zhi-juan 《Journal of Hainan Medical University》 CAS 2023年第12期18-23,共6页
Objective:To investigate the mechanism of the effect of Daodi Tongguan Decoction on ovarian function in rats with premature ovarian failure.Methods:Forty SD female rats with regular estrous cycle were randomly divided... Objective:To investigate the mechanism of the effect of Daodi Tongguan Decoction on ovarian function in rats with premature ovarian failure.Methods:Forty SD female rats with regular estrous cycle were randomly divided into the blank group,the model group,the positive group(Bujiale 0.099 mg/kg),the Daodigitongguan decoction high-dose group(1.4 g/100 g)and the Daodigitongguan decoction medium-dose group(0.7 g/100 g).The model group,positive group,Daodi Tongguan Decoction high-dose group and Daodi Tongguan decoction medium-dose group were given Tripterygium wilfordii polyglycoside tablets suspension(50 mg/kg)by continuous gavage for 14 days to establish a rat model of premature ovarian failure.After the modeling,each group was given the corresponding intervention agent for 28 consecutive days.After the intervention,serum and ovarian tissue were collected from rats in each group.The morphological structure of rat ovarian tissue was observed after HE staining.Serum AMH level was determined by ELISA.The expressions of Bcl-2,Bax and VEGF in ovarian tissue were detected by IHC.The apoptosis of granulosa cells in ovary was observed by TUNEL.Results:Compared to the normal group,the growth follicles in the model group were reduced and the atretic follicles were increased.Serum AMH level was significantly decreased(P<0.01).The expression of Bax protein in ovarian tissue was increased(P<0.01).The protein expressions of Bcl-2 and VEGF were decreased(P<0.01,P<0.05),and the apoptosis rate of follicular granulosa cells in ovarian tissue was increased(P<0.01).Compared to the molding group,the serum AMH level in the TCM dose groups was increased to varying degrees,and the change of the AMH in high-dose group was the most significant(P<0.05).The expression of Bax protein in ovarian tissue decreased(P<0.05),while the expression of Bcl-2 and VEGF protein increased(P<0.05,P<0.05).The apoptosis rate of follicular granulosa cells in ovarian tissue was decreased in the high dose group(P<0.05).Conclusion:Daodi Tongguan Decoction can improve the histological morphology of ovary and relieve ovarian injury,and its mechanism may be related to improving the sex hormone level of POF model rats,reducing the expression level of Bax protein in ovarian tissue,increasing the expression level of Bcl-2 and VEGF protein in ovarian tissue,and reducing the apoptosis rate of follicular granulosa cells in ovarian tissue. 展开更多
关键词 LPremature ovarian failure Daodi tong guan soup VEGF BAX Bcl-2 APOPTOSIS
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Evaluation and Improvement Strategies for Slow Traffic Systems Based on Multi-source Big Data:A Case Study of Shijingshan District of Beijing City
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作者 LI Yiwen 《Journal of Landscape Research》 2023年第4期62-64,68,共4页
The slow traffic system is an important component of urban transportation,and the prerequisite and necessary condition for Beijing to continue promoting“green priority”are establishing a good urban slow traffic syst... The slow traffic system is an important component of urban transportation,and the prerequisite and necessary condition for Beijing to continue promoting“green priority”are establishing a good urban slow traffic system.Shijingshan District of Beijing City is taken as a research object.By analyzing and processing population distribution data,POI data,and shared bicycle data,the shortcomings and deficiencies of the current slow traffic system in Shijingshan District are explored,and corresponding solutions are proposed,in order to provide new ideas and methods for future urban planning from the perspective of data. 展开更多
关键词 Multi-source data Slow traffic system Shijingshan district
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A new approach towards the sustainability of urban-rural integration:The development strategy for central villages in the Abbasiya District of Iraq using GIS techniques
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作者 Ahmed Hussein ALLAWI Haider Mohammed Jawad AL-JAZAERI 《Regional Sustainability》 2023年第1期28-43,共16页
The development of rural areas usually has a positive impact on the urban-rural integration. This study explores an innovative approach to stimulate rural development by proposing qualified villages as central village... The development of rural areas usually has a positive impact on the urban-rural integration. This study explores an innovative approach to stimulate rural development by proposing qualified villages as central villages that can provide basic urban services for their residents and residents of neighboring villages. This approach can contribute to overcoming the various problems that rural areas faced at the social, economic, and environmental levels. It seeks to achieve spatial sustainability of rural areas, representing a new approach by integrating urban development methods to revitalize rural villages. The study analyzed 15 villages belonging to Abbasiya District of AL Kufa City in the Najaf Governorate of Iraq. Based on the GIS techniques and the analysis of urban service indicators(village population, percentage of urban building materials used in villages, distance between village and health centers, distance between village and main roads, nature of economic activity, distance between village and educational institutions, distance between village and drinking water sources, number of communication towers, and distance between village and urban administrative center), this study proposed that Abu Gharb and Albu Ghraib can served as central villages in Abbasiya District in the future. This study establishes a new rural spatial structure to achieve rural sustainable development, improves the development status of rural areas, and provides a theoretical basis for the government and relevant institutions to use urban service indicators, achieving rural sustainable development and formulating relevant development policies in Abbasiya District. 展开更多
关键词 Central villages Spatial reorganization Rural sustainable development Urban-rural integration Urban service Abbasiya district Iraq
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Impacts of Sulfur and Microalgae Co-fertilization on Saline-alkaline Soil of Sunflower Field in Hetao Irrigation District
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作者 Ruimin DONG Liming LAI +5 位作者 Peng ZHANG Yanxiong ZHAO Yang YANG Haiwei WANG Man WANG Yuelong DONG 《Asian Agricultural Research》 2023年第3期30-33,36,共5页
[Objectives]To evaluate the impacts of the elemental sulfur(S 0)and micro-algae(MA)co-fertilization on saline-alkaline soil of sunflower field in the Hetao Irrigation District(HID).[Methods]The greenhouse pot experime... [Objectives]To evaluate the impacts of the elemental sulfur(S 0)and micro-algae(MA)co-fertilization on saline-alkaline soil of sunflower field in the Hetao Irrigation District(HID).[Methods]The greenhouse pot experiment was conducted with four treatments:control(CK),single S 0 fertilization(S),single MA fertilization(A),and S 0 and MA co-fertilization(SA)for comparing the selected soil properties and sunflower plant heights and weights in different treatments.[Results]The results showed that the mean soil organic matter(SOM)under the SA(25.08 g/kg)was significantly higher than that for the CK(20.59 g/kg),S(22.47 g/kg),and A(22.95 g/kg).The mean pH under the SA(7.75)was significantly lower than that for the CK(8.14),S(7.82),and A(7.96).The mean soil exchangeable Na+concentration under the SA was significantly lower than that for the S.The mean soil electrical conductivity(EC)under the SA was 9.76%lower than that for the S.The means of Cl-(1.22 g/kg)and SO 2-4(1.90 g/kg)in soil under the SA were lower than that for the S(1.30,2.06 g/kg)and A(1.31,1.97 g/kg),respectively.For plant height 3 at the late stage of plant growth,the mean plant height 3 under the SA(89.00 cm)was higher than that of the CK(69.60 cm)and A(74.33 cm).The total weights of the fresh sunflower heads,fresh stems,and dry seeds under the SA were higher than that for the CK,S,and A.[Conclusions]In conclusion,the S 0 and MA co-fertilization had positive effects on improving saline-alkaline soils,the soil under the S 0 and MA co-fertilization could be better conditions for promoting sunflower growth than that for the S,Z,and CK,and thereby the S 0 and MA co-fertilization could be a new idea to improve saline-alkaline soil in the cold and arid regions. 展开更多
关键词 Sulfur and microalgae co-fertilization SUNFLOWER Saline-alkaline soil Hetao Irrigation district(HID)
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Risk behaviours associated with HIV and AIDS among couples in Rwamiko Sector, Gicumbi District, Rwanda
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作者 Jean Marie Vianney Tuyisenge Erigene Rutayisire 《Life Research》 2023年第3期59-65,共7页
Background:Risk behaviours have been linked to the spread of the Human Immunodeficiency Virus(HIV)epidemic in both urban and rural areas.Despite the progress made in the fight against HIV,it remains a public health co... Background:Risk behaviours have been linked to the spread of the Human Immunodeficiency Virus(HIV)epidemic in both urban and rural areas.Despite the progress made in the fight against HIV,it remains a public health concern worldwide.Risk behaviours such as not using condoms,having multiple sexual partners,and engaging in early sexual activity increase the risk of HIV infection.Therefore,it is important to assess these risk behaviours and understand the relationship between different factors and HIV,specifically among couples,in order to better understand the dynamics of the epidemic.The main objective of this study was to assess risk behaviours for HIV and AIDS among couples in Rwamiko sector,Gicumbi District,and suggest appropriate interventions for this group.Methods:This cross-sectional survey aimed to assess associated HIV and AIDS risk behaviours among couples in Rwamiko Sector,Gicumbi District,in order to determine the dynamics of the epidemic in this group and suggest appropriate interventions.Data was collected using a self-administered questionnaire and a multistage cluster random sampling technique.The collected data was then computed,analyzed,and presented in the form of tables and figures.Descriptive statistics were used to analyze all variables.Multivariate logistic regression was used to calculate odds ratios and 95%confidence intervals(CI)to investigate the relationship between the assessed factors,such as independent and dependent variables.The association between the studied factors was described using odds ratios with 95%CIs.Results:The majority of respondents were in the age group of 30-39 years.All respondents were married,and approximately 45%had completed primary education.The majority of respondents were unemployed.Respondents reported receiving HIV information from multiple sources,including radio,TV,films,school,church,health workers,parents,and friends.The findings of this study showed that some participants had knowledge about HIV transmission and prevention,while others did not.The proportion of respondents with a high level of HIV and AIDS knowledge was 30.61%(n=60),while moderate knowledge accounted for 53.57%(n=105).Furthermore,the proportion of respondents with a low level of knowledge on HIV and AIDS was 15.81%(n=31).The attitude towards HIV and AIDS was positive for 58.16%(n=114)of respondents,while 41.83%(n=82)had a negative attitude.None of the respondents reported using injection drugs.Significant associations were found between age(P-value=0.002,odds ratio(OR)=3.4,95%CI=1.59-7.67),gender(p=0.001,OR=2.6,95%CI=1.44-4.68),and alcohol consumption.There was also an association between age(P=0.001,OR=5.13,95%CI=2.04-12.91)and having multiple sexual partners.Conclusion:The majority of couples in Rwamiko Sector,Gicumbi District have a moderate level of knowledge and a positive attitude towards HIV and AIDS.However,the proportions of respondents with a low level of knowledge and a negative attitude should not be overlooked.The results of this study suggest the need to improve communication messages related to HIV,its transmission risks,and safer sexual behavior,particularly among couples in Rwamiko Sector,Gicumbi District. 展开更多
关键词 Risk Behaviour Couples Rwamiko Sector Gicumbi district
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Big Data Analysis and Optimization Suggestions of Cultural Facilities in Shijingshan District,Beijing City
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作者 KANG Yue YUAN Leyi DING Zhengli 《Journal of Landscape Research》 2023年第2期49-53,共5页
With the successful holding of Beijing Winter Olympic Games in 2022,the planning and cultural services of Shijingshan District have been reviewed,but the systematic planning theory has not been fully applied.Through t... With the successful holding of Beijing Winter Olympic Games in 2022,the planning and cultural services of Shijingshan District have been reviewed,but the systematic planning theory has not been fully applied.Through the big data research method,the location advantages and disadvantages of Shijingshan District were analyzed,and the distribution of its cultural facilities was defined.Feasible optimization schemes were proposed according to its advantages and disadvantages as well as the experience and conditions of the Winter Olympics. 展开更多
关键词 BEIJING Shijingshan district Cultural service facilities Big data Renovation of old functional areas
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Research on the Public Perception of Yangzhou Historical and Cultural Districts Based on Network Review Text Analysis
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作者 WU Tao SHAO Yuanhua 《Journal of Landscape Research》 2023年第3期36-41,共6页
The historical and cultural districts of a city serve as important cultural heritage and tourism resources.This paper focused on four such districts in Yangzhou and performed semantic analysis on online public comment... The historical and cultural districts of a city serve as important cultural heritage and tourism resources.This paper focused on four such districts in Yangzhou and performed semantic analysis on online public comments using ROST CM6 software.According to the high frequency words,attention preference of district site elements,activities and feelings in Yangzhou historical and cultural districts were analyzed.Through the analysis of semantic network and public emotional tendency,the relationship between the protection and utilization of Yangzhou historical and cultural districts and the perception and demand of users were discussed,and some suggestions for the protection,utilization and renewal of historical and cultural districts were put forward. 展开更多
关键词 Yangzhou historical and cultural districts Text analysis Public perception Protection and renewal
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Yangrou Hutong:Beijing’s Low-Key Jewelry District
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作者 Zheng Yang 《ChinAfrica》 2011年第11期52-52,共1页
YANGROU Hutong is 600 years old.Located in the Xisi area of Beijing’s Xicheng District,the area was originally a trading market for cattle,which usually ended up in the imperial kitchen.But with the name Yangrou(mean... YANGROU Hutong is 600 years old.Located in the Xisi area of Beijing’s Xicheng District,the area was originally a trading market for cattle,which usually ended up in the imperial kitchen.But with the name Yangrou(meaning mutton),butchers and mutton stores replaced the cattle traders starting in the Ming Dynasty (1368-1644).In those days,cries of sellers and the pungent smell of mutton overwhelmed every passerby. But today,those smells and sounds are 展开更多
关键词 Yangrou Hutong:Beijing’s Low-Key Jewelry district
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