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Properties and Characterization of Two Clays Raw Material from Mountain District (West of Côte d’Ivoire) for Use in Low-Carbon Cements
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作者 Wedjers Max Robin Manouan Bi Irié Hervé Gouré Doubi +3 位作者 Lébé Prisca Marie-Sandrine Kouakou Atta Kouamé Brice Koffi Alfred Niamien Kouamé Namory Méité 《Advances in Materials Physics and Chemistry》 CAS 2024年第8期137-145,共9页
This work was devoted to the study of the physico-chemical properties of two clay minerals from the Mountain District (West Côte d'Ivoire) referenced ME1 and ME2. These samples were characterized by the exper... This work was devoted to the study of the physico-chemical properties of two clay minerals from the Mountain District (West Côte d'Ivoire) referenced ME1 and ME2. These samples were characterized by the experimental techniques, such as X-ray diffraction (XRD), Infrared spectroscopy (IR), Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES), Differential Thermal Analysis and Thermogravimetry (DTA-TG), Brunauer, Emett and Teller method (BET), laser particle size analysis and Scanning Electron Microscope (SEM). The main results of these analyses reveal that the two clay samples mainly contain quartz (52.91% for ME1 and 51.72% for ME2), kaolinite (36.60% for ME1 and 41.6% for ME2) and associated phases, namely goethite and hematite (13.47% for ME1 and 11.00% for ME2). The specific surface values obtained for samples ME1 and ME2 are 34.78 m2/g and 29.18 m2/g respectively. The results obtained show that the samples studied belong to the kaolinite family. After calcination, they could have good pozzolanic activity and therefore be used in the manufacture of low-carbon cements. 展开更多
关键词 QUARTZ KAOLINITE Mountain district Low-Carbon Cements
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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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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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Improving the Quality of Public Space in Old Residential Areas Based on Superposition and Intervention:A Case Study of Baihuazhou District of Nanchang City
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作者 LI Shengnan 《Journal of Landscape Research》 2024年第4期13-16,20,共5页
With the development of cities,China has entered an era of stock planning.The functions of old residential areas in urban development can no longer meet the needs of residents in the new era for a better life,and new ... With the development of cities,China has entered an era of stock planning.The functions of old residential areas in urban development can no longer meet the needs of residents in the new era for a better life,and new standards have been put forward for the quality of public spaces for living.This paper analyzes and sorts out the characteristics and problems of the public space in the old residential areas of Baihuazhou district.Combining superposition and intervention techniques,the spatial,historical,cultural and other characteristic elements of the residential areas are preserved to the greatest extent.The public space in the old residential areas of Baihuazhou District is updated and reconstructed in order to achieve the goal of improving the quality of its public space. 展开更多
关键词 Superposition and intervention Old residential area Public space Quality improvement Baihuazhou district
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Analysis of Characteristics and Meteorological Influencing Factors of Air Pollution in Luojiang District,Deyang City
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作者 Zirui ZUO Hao XIANG +1 位作者 Huan YANG Yuxiang GAO 《Meteorological and Environmental Research》 2024年第4期24-28,共5页
Based on the monitoring data of ambient air quality and meteorological observation data,the characteristics and meteorological influencing factors of air pollution in Luojiang District of Deyang City from 2018 to 2022... Based on the monitoring data of ambient air quality and meteorological observation data,the characteristics and meteorological influencing factors of air pollution in Luojiang District of Deyang City from 2018 to 2022 were analyzed.The results show that from 2018 to 2022,the main air pollutants affecting the air quality of Luojiang District of Deyang City were PM 2.5 and PM 10,and the primary pollutant on heavy pollution days was basically PM 2.5.PM 2.5 and PM 10 pollution showed obvious seasonal differences,and PM 2.5 concentration exceeded the limit mainly in spring and winter,among which it was the most serious in early spring,especially in January and February,followed by December.PM 10 exceeding the standard had a high seasonal correlation with PM 2.5 exceeding the standard,mainly in spring and winter,among which it was the most serious in winter,especially in December,followed by January.PM 2.5 and PM 10 pollution showed an overall weakening trend.PM 2.5 and PM 10 concentration were closely related to meteorological factors such as temperature,relative humidity,wind speed,precipitation and air pressure,and were mainly affected by rainfall. 展开更多
关键词 Luojiang district of Deyang City Air pollution METEOROLOGY CHARACTERISTICS
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区县级医院学科发展竞争力指标体系研究 被引量:2
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作者 石景芬 王宇婵 +3 位作者 刘志会 廖萱 罗月 刘军 《中国医院》 北大核心 2024年第5期37-40,共4页
目的:构建一套科学实用的区县级医院学科发展竞争力评价指标。方法:基于PEST+SWOT分析法探索区县级医院学科发展关键要素及其运行机制,初筛学科发展竞争力指标体系;运用德尔菲法开展两轮专家咨询确定指标体系及权重。结果:该指标体系包... 目的:构建一套科学实用的区县级医院学科发展竞争力评价指标。方法:基于PEST+SWOT分析法探索区县级医院学科发展关键要素及其运行机制,初筛学科发展竞争力指标体系;运用德尔菲法开展两轮专家咨询确定指标体系及权重。结果:该指标体系包括一级指标4个维度(医院管理及综合实力、人才队伍建设、科研创新、教育培训)、二级指标16个、三级指标38个。两轮专家咨询积极系数均为100%,各指标评分变异系数CV值均<0.2,专家协调程度较高,专家权威系数分别为0.94和0.91;各指标第二轮专家评分均值>3.8,大多数指标得分4以上。结论:经专家反馈和统计检验,该指标体系具备科学性和实用性。 展开更多
关键词 PEST+SWOT分析 德尔菲法 区县级医院 学科发展 指标体系
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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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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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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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降水和地下水开采对通辽市科尔沁区潜水位的影响 被引量:1
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作者 束龙仓 张彤豪 +2 位作者 澈丽木格 刘圣昱 刘波 《吉林大学学报(地球科学版)》 CAS CSCD 北大核心 2024年第3期954-966,共13页
变化环境下(气候变化和人类活动)潜水位动态演化过程识别是当前我国乃至全球水资源领域面临的主要科学问题。为了分析多影响因素下的潜水位时空动态变化,以降水和地下水开采为例,基于通辽市科尔沁区2016年1月—2019年12月实测地下水位... 变化环境下(气候变化和人类活动)潜水位动态演化过程识别是当前我国乃至全球水资源领域面临的主要科学问题。为了分析多影响因素下的潜水位时空动态变化,以降水和地下水开采为例,基于通辽市科尔沁区2016年1月—2019年12月实测地下水位动态数据,采用Mann-Kendall(MK)趋势检验和栅格代数法分析了区域潜水位的时空变化规律,并利用交叉小波分析、斯皮尔曼相关系数和多元线性回归法进一步量化分析了不同区域降水和地下水开采对潜水位的影响。结果表明:研究时段内科尔沁区潜水位总体呈下降趋势,年均降幅为0.36 m,中部和西部地区潜水位下降较为严重;根据潜水位差值空间分布特征,将研究区划分为潜水位基本平衡区、下降区和严重下降区,其分别占研究区总面积的9.88%、49.65%和40.47%;基本平衡区的潜水位受降水因素影响显著,受地下水开采变化影响极小,下降区和严重下降区潜水位受地下水开采的影响相较于降水影响更大。 展开更多
关键词 通辽市科尔沁区 潜水位动态 降水 地下水开采 交叉小波
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智慧水利理论体系与数字孪生流域虚拟模型研究成果述要 被引量:3
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作者 冶运涛 蒋云钟 +5 位作者 曹引 尚毅梓 顾晶晶 董甲平 黄建雄 关昊哲 《中国水利》 2024年第5期41-51,共11页
智慧水利是水利高质量发展的显著标志之一。围绕智慧水利理论体系不完善、流域映射精准度不高、模型精度不高、决策支撑程度低等问题,建立了由智慧流域基础理论、数字孪生流域基础理论和智能水网理论框架组成的智慧水利理论体系,研究了... 智慧水利是水利高质量发展的显著标志之一。围绕智慧水利理论体系不完善、流域映射精准度不高、模型精度不高、决策支撑程度低等问题,建立了由智慧流域基础理论、数字孪生流域基础理论和智能水网理论框架组成的智慧水利理论体系,研究了由数字孪生感知节点模型、数字孪生降水遥感模型、数字孪生蒸散发遥感模型、数字孪生土壤水遥感模型、数字孪生水体遥感模型、数字孪生地下水遥感模型、数字孪生水质遥感模型组成的数字孪生流域感知模型,构建了由数字孪生流域水文模型、数字孪生水动力水质模型、数字孪生动态调控模型、数字孪生虚拟仿真模型、数字孪生协同决策模型、数字孪生并行组合模型等组成的数字孪生流域虚拟模型。研究成果可为我国智慧水利建设提供理论基础和技术支撑。 展开更多
关键词 智慧水利 智慧流域 数字孪生流域 智能水网 数字孪生水网 数字孪生水利工程 数字孪生灌区
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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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基于PSR模型的城市河流湿地生态健康评价——以苏州市姑苏区为例 被引量:1
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作者 朱颖 王春文 +1 位作者 周昕宇 冯育青 《湿地科学与管理》 2024年第1期41-45,51,共6页
城市河流湿地的生态健康是城市生态可持续的重要基础。本研究以苏州市姑苏区河流湿地为研究对象,运用层次分析法与模糊综合评价法评价其河流湿地健康状况。结果表明:苏州市姑苏区河流湿地的生态健康状况处于“中等”等级,接近“亚健康... 城市河流湿地的生态健康是城市生态可持续的重要基础。本研究以苏州市姑苏区河流湿地为研究对象,运用层次分析法与模糊综合评价法评价其河流湿地健康状况。结果表明:苏州市姑苏区河流湿地的生态健康状况处于“中等”等级,接近“亚健康”状态;准则层的排序权重为状态层指标>压力层指标>响应层指标,说明状态层指标能直观反映河流湿地的健康状态,其状态层的综合健康指数为0.658;各河段健康状态与其所对应的城市流域所承受的压力存在着密切联系,城市的建设强度和植被覆盖率因素对姑苏区河流湿地的健康状态具有显著影响。 展开更多
关键词 城市河流湿地 PSR模型 模糊综合评价 生态健康评价 姑苏区
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交通出行提质推动城市转型升级——中国城市交通发展论坛第34次研讨会 被引量:1
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作者 陈小鸿 崔扬 +9 位作者 王婷 景国胜 金伟 白雪洁 郭继孚 钱林波 罗斌 张耘华 董志国 丘银英 《城市交通》 2024年第1期107-123,共17页
城市交通发展重点由增量建设转入存量优化阶段,通过优化城市既有交通设施提升居民出行品质,是适应新时代城市交通需求、助力城市发展转型升级的必然要求。中国城市交通发展论坛于2023年12月11日在天津市举办了2023年第4次(总第34次)常... 城市交通发展重点由增量建设转入存量优化阶段,通过优化城市既有交通设施提升居民出行品质,是适应新时代城市交通需求、助力城市发展转型升级的必然要求。中国城市交通发展论坛于2023年12月11日在天津市举办了2023年第4次(总第34次)常规研讨会,主题为“交通出行提质推动城市转型升级”,聚焦高质量发展目标下城市交通面临的机遇与挑战、新趋势与战略思路、发展路径和关键举措。与会嘉宾围绕面向2035年中国城市交通发展战略、传统商业街区更新的经验与路径、建设国际消费中心城市、天津和广州高质量发展转型的实践案例等展开研讨,提出多项城市交通转型升级和城市高品质宜居发展策略。本次论坛由中国城市交通发展论坛组委会主办,天津市城市规划设计研究总院有限公司承办。 展开更多
关键词 交通政策 城市转型升级 传统商业街区更新 国际消费中心城市
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人本视角下的历史文化街区更新思考 被引量:5
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作者 张菁 徐萌 +1 位作者 李晨然 李佳薇 《中国名城》 2024年第2期3-11,共9页
历史文化街区是我国历史文化名城保护的核心地区,也是保护与发展冲突最为集中的地方。在城市更新的时代背景下,历史文化街区在更新发展过程中往往面临建筑质量维护欠佳、基础设施和公共服务设施缺乏、历史环境整治不当、生活延续性割裂... 历史文化街区是我国历史文化名城保护的核心地区,也是保护与发展冲突最为集中的地方。在城市更新的时代背景下,历史文化街区在更新发展过程中往往面临建筑质量维护欠佳、基础设施和公共服务设施缺乏、历史环境整治不当、生活延续性割裂等问题。在“以人为本”的价值导向下,重点关注街区安全、全龄友好、文脉传承、合理发展和公众参与5个方面,结合部分城市的实践经验,对历史文化街区更新的技术方法和实践模式进行综合思考。 展开更多
关键词 以人为本 历史文化街区 文化视角 城市更新
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考虑动态定价和碳交易的多园区综合能源服务商低碳合作优化策略 被引量:1
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作者 栗然 吕慧敏 +2 位作者 彭湘泽 王炳乾 祝晋尧 《太阳能学报》 EI CAS CSCD 北大核心 2024年第3期337-346,共10页
为解决多园区综合能源服务商参与综合能源市场和碳交易市场带来的利益分配和动态定价问题,该文提出一种新的多园区服务商合作交易框架。首先,设计阶梯式碳交易下多园区综合能源服务商合作运行交易机制,针对区域零售市场制定动态价格,以... 为解决多园区综合能源服务商参与综合能源市场和碳交易市场带来的利益分配和动态定价问题,该文提出一种新的多园区服务商合作交易框架。首先,设计阶梯式碳交易下多园区综合能源服务商合作运行交易机制,针对区域零售市场制定动态价格,以指导各园区服务商购能行为;其次,在新型电力系统的逐步构建下,根据新能源占比变化,完善碳配额与碳排放模型,并通过市场下阶梯式碳交易机制约束各园区的碳排放;最后,建立多园区服务商纳什议价模型,将所建模型分解为联盟成本最小化与电热交易支付谈判子问题,通过算例验证所提模型和方法能提高各园区参与联盟主动性,并有效降低各园区碳排放和总运行成本。 展开更多
关键词 多园区综合能源服务商 综合能源市场 碳交易 动态定价 纳什议价
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非正式治理的制度化运作:管区制与乡镇治理现代化的路径选择 被引量:1
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作者 袁明宝 《西南大学学报(社会科学版)》 北大核心 2024年第1期79-88,共10页
管区作为一种非正式的组织设置,在乡镇与村级治理单元之间建构出实体性质的中间结构,具有低成本、非正式性和制度稳定性等特点,成为乡镇政权的延伸。管区设置虽然增加了乡镇内部的“委托—代理”层级,但通过行政体制上的形式化设置和实... 管区作为一种非正式的组织设置,在乡镇与村级治理单元之间建构出实体性质的中间结构,具有低成本、非正式性和制度稳定性等特点,成为乡镇政权的延伸。管区设置虽然增加了乡镇内部的“委托—代理”层级,但通过行政体制上的形式化设置和实践中的非正式运作,具有了超越科层体制约束的优势,借助激励动员和组织重构实现了有效治理。管区借助乡镇内部人力资源的重新配置,在不变体制的情况下进行机制创新,实现了非正式治理的制度化运作,匹配了当前乡村社会转型和治理转型的需求,成为当前强国家治理背景下探索乡镇治理现代化的一条可行路径。 展开更多
关键词 管区制 非正式治理 准行政组织 制度化运作 行政发包 乡镇治理现代化
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2013-2022年北京市朝阳区HIV确证实验结果分析
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作者 黄平 孙灵利 +2 位作者 李崇 李丽 刘洁 《中国人兽共患病学报》 CAS CSCD 北大核心 2024年第5期478-482,共5页
目的分析2013-2022年北京市朝阳区筛查结果为阳性的HIV(艾滋病)病毒确证实验结果,了解辖区内HIV检测工作情况。方法辖区内58家筛查实验室上送的13128份HIV筛查阳性样本,通过免疫印迹实验(Western blot,WB)进行确证实验,应用SPSS22.0对... 目的分析2013-2022年北京市朝阳区筛查结果为阳性的HIV(艾滋病)病毒确证实验结果,了解辖区内HIV检测工作情况。方法辖区内58家筛查实验室上送的13128份HIV筛查阳性样本,通过免疫印迹实验(Western blot,WB)进行确证实验,应用SPSS22.0对实验结果进行统计学分析。结果2013-2022年本确证实验室检出HIV-1抗体阳性样本8417件,HIV-2阳性样本未检出,不确定样本1263份,阴性样本3448份。HIV-1抗体阳性中,男性占94.32%,性别差异有统计学意义;年龄在19~30岁组占48.65%;WB条带中全条带和次全带占96.92%,其中gp160检出率为99.94%,gp120检出率为99.67%。结论2013-2022年北京市朝阳区HIV-1抗体阳性以男性为主,年龄主要分布在19到30岁。不同年龄、性别、职业和送检人群的HIV-1抗体不确定的构成比差异不大。HIV-1抗体阳性样本的WB条带显示全条带和次全带占比最高。 展开更多
关键词 朝阳区 HIV 确证实验 条带
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