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Analyses on cancer incidence and mortality in Huai’an area,China,from 2009 to 2011 被引量:3
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作者 Guangjin Yuan Qianwen Li +5 位作者 Yunxiang Du Shunlin Shan Zhimin Wang Enchun Pan Yuan He Ting Wang 《The Chinese-German Journal of Clinical Oncology》 CAS 2012年第9期497-503,共7页
Objective: The aim of the study was to investigate the cancer incidence and mortality in Huai'an area, China, from 2009 to 2011. Methods: The data about cancer incidence and mortality were provided by Huai'an Canc... Objective: The aim of the study was to investigate the cancer incidence and mortality in Huai'an area, China, from 2009 to 2011. Methods: The data about cancer incidence and mortality were provided by Huai'an Cancer Registry, China. Incidence and mortality rates, and standardized rates were calculated by age, gender, areas (urban and rural areas of Huai'an) and cancer sites. Results: The crude incidence rate for all cancer sites was 205.60/105 and the standardized incidence rate was 166.22/10. Both the crude and standardized rates were higher in urban area than in rural area for both sexes. The inci- dence rates increased in people aged 40 and over, and the peak ages of incidence were between 70-75 in both males and females. The crude mortality rate for all cancer sites was 153.88/105 and the standardized mortality rate was 122.14/105. Both the crude and standardized rates were similar in urban and rural areas for both men and women. The mortality rates were at low level under the age 50 in both sexes, but increased after the age 50, reaching the peak at the ages of 80-85 in both males and females. The top 10 most common cancer sites in rank were esophagus, stomach, lung, liver, colon-rectum, breast, pancreas, cervix uteri, brain and central nervous system, and leukemia, accounting for 87.56% of all cancers. The top 10 most leading causes of cancer death in order were cancers of esophagus, lung, liver, stomach, colon-rectum, pancreas, brain and central nervous system, leukemia, breast and lymphoma, accounting for 90.53% of all cancer deaths. Conclusion: Cancer is one kind of major diseases threatening people's health in Huai'an area, China. Cancer prevention and control should be enhanced, especially for esophageal cancer. 展开更多
关键词 CANCER INCIDENCE MORTALITY huai'an area
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Analyses on Cancer Incidence and Mortality in Huai’an Area, China, 2010 被引量:1
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作者 Qin Zhang Enchun Pan +2 位作者 Yuan He Wei Hu Chuang Wang 《Open Journal of Preventive Medicine》 2014年第6期504-512,共9页
Objective: The aim of this study was to investigate the cancer incidence and mortality in Huai’an area, China, 2010. Methods: On basis of the criteria of data quality from National Central Cancer Registry (NCCR), dat... Objective: The aim of this study was to investigate the cancer incidence and mortality in Huai’an area, China, 2010. Methods: On basis of the criteria of data quality from National Central Cancer Registry (NCCR), data submitted from 8 registries in Huai’an area in 2010 were checked and evaluated. Descriptive analysis included incidence and mortality stratified by areas (urban/rural), sex, age group and cancer sites. Results: The crude incidence rate was 231.17/100,000 (males 276.04/100,000, females 183.87/100,000), age-standardized incidence rate by Chinese standard population (ASIRC) was 179.53/100,000 and by World standard population (ASIRW) was 177.24/ 100,000. The incidence rates increased rapidly in people aged 40 and over, and the peak ages of incidence were at 75 - 79 (males over 85, females at 75 - 79). The cancer mortality rate was 151.26/100,000 (186.06/100,000 in males and 114.58/100,000 in females), age-standardized mortality rate by Chinese standard population (ASMRC) was 116.67/100,000 and by World standard population (ASMRW) was 115.64/100,000. The mortality rates increased rapidly after the age of 50, reaching the peak at the ages over 85 in both males and females. Esophageal, lung, gastric, liver, colorectal, breast, pancreas, lymphoma, brain and central nervous system,?cervical were the most common cancer incident sites. Esophageal, lung, liver, gastric, colorectal, pancreatic, brain and central nervous system, leukemia, breast and lymphoma were the most common cancer sites of death. Conclusions: The data quality of cancer registration is improving. As cancer burden remained high and was different between urban and rural areas, prevention and control should be implemented based on practical situation. 展开更多
关键词 CANCER INCIDENCE MORTALITY huai’an area
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Analysis on the epidemiological characteristics of esophageal cancer in Huai’an area,China from 2009 to 2011
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作者 Guangjin Yuan Qianwen Li +5 位作者 Yuxiang Du Shunlin Shan Zhimin Wang Enchun Pan Yuan He Ting Wang 《The Chinese-German Journal of Clinical Oncology》 CAS 2012年第9期504-507,共4页
Objective: The aim of our study was to investigate the epidemiological characteristics of esophageal cancer from 2009 to 2011 in Huai'an area, China. Methods: The data about the incidence and mortality of esophage... Objective: The aim of our study was to investigate the epidemiological characteristics of esophageal cancer from 2009 to 2011 in Huai'an area, China. Methods: The data about the incidence and mortality of esophageal cancer were provid- ed by Huai'an Cancer Registry, and the epidemiological characteristics of the disease were analyzed. Results: Esophageal cancer was not only the first most common cancer, but also the leading cause of cancer death in Huai'an area. The crude and standardized incidence rates were 62.91/10 5 and 49.92/10 5 , and the crude and standardized mortality rates were 46.75/10 5 and 36.87/10 5 , respectively. The sex ratio (male-female) was 1.69:1 in incidence, and the incidence increased in people aged 40 years and over, reaching the peak at the ages of 70-75 years. The mortality rate was at low level under the age of 50 years, but increased after the age of 50 years, reaching the peak at the age of 75-85 years. Incidence and mortality rates varied regionally with the highest rate found in Chuzhou district (90.76/10 5 and 67.17/10 5 ) and lowest rate observed in Qinghe district (32.41/10 5 and 8.75/10 5 ). Conclusion: Esophageal cancer is the major burden of cancer in Huai'an area, and has marked geographic distribution difference. The key period of age for screening and prevention of the disease is 55-85 years old. 展开更多
关键词 esophageal cancer INCIDENCE MORTALITY huai'an area
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Spatio-temporal Evolution of the Rural Regional System and Its Evolution Mechanism in Huang-Huai-Hai Area of China 被引量:1
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作者 CHENG Mingyang CHEN Huiling 《Chinese Geographical Science》 SCIE CSCD 2023年第1期51-68,共18页
The problem of rural development arises from the evolution of rural regional system.It is urgent to deepen the research on the evolution process and mechanism of rural regional system.However,there are relatively few ... The problem of rural development arises from the evolution of rural regional system.It is urgent to deepen the research on the evolution process and mechanism of rural regional system.However,there are relatively few studies on rural development from the perspective of the evolution process,driving mechanism and evolution mechanism of rural regional system.Therefore,this study took Huang-Huai-Hai Area for example,started with the systematicness of the rural regional system,the spatio-temporal pattern and driving mechanism of rural regional system evolution,and further summarized and refined the evolution mechanism of the rural regional system.The methods of spatial pattern analysis,gray correlation degree and geographical detection were adopted.The results showed that the problems in rural areas were often dominated by one factor and produced by the joint action of many factors.Factors such as county urbanization,county economy,county public service,agricultural mechanization,surrounding cities and convenient transportation will affect the evolution of rural regional systems.Based on the evolution of the elements in the rural regional system,the evolution types of rural regional system can be divided into decline type,equilibrium type and growth type.This study can provide a reference for understanding the process of rural rise and fall and can also guide rural revitalization and rural sustainable development. 展开更多
关键词 rural evolution rural regional system population-land-industry evolution mechanism rural revitalization Huang-huai-Hai area(HHHA)
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Ecological-Based Mining:A Coal-Water-Thermal Collaborative Paradigm in Ecologically Fragile Areas in Western China 被引量:2
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作者 Xiaoxiu Liu Yifan Zeng +3 位作者 Qiang Wu Shihao Meng Jiyue Liang Zhuping Hou 《Engineering》 SCIE EI CAS CSCD 2024年第7期209-222,共14页
A substantial reduction in groundwater level,exacerbated by coal mining activities,is intensifying water scarcity in western China’s ecologically fragile coal mining areas.China’s national strategic goal of achievin... A substantial reduction in groundwater level,exacerbated by coal mining activities,is intensifying water scarcity in western China’s ecologically fragile coal mining areas.China’s national strategic goal of achieving a carbon peak and carbon neutrality has made eco-friendly mining that prioritizes the protection and efficient use of water resources essential.Based on the resource characteristics of mine water and heat hazards,an intensive coal-water-thermal collaborative co-mining paradigm for the duration of the mining process is proposed.An integrated system for the production,supply,and storage of mining companion resources is achieved through technologies such as roof water inrush prevention and control,hydrothermal quality improvement,and deep-injection geological storage.An active preventive and control system achieved by adjusting the mining technology and a passive system centered on multiobjective drainage and grouting treatment are suggested,in accordance with the original geological characteristics and dynamic process of water inrush.By implementing advanced multi-objective drainage,specifically designed to address the“skylight-type”water inrush mode in the Yulin mining area of Shaanxi Province,a substantial reduction of 50%in water drillings and inflow was achieved,leading to stabilized water conditions that effectively ensure subsequent safe coal mining.An integrated-energy complementary model that incorporates the clean production concept of heat utilization is also proposed.The findings indicate a potential saving of 8419 t of standard coal by using water and air heat as an alternative heating source for the Xiaojihan coalmine,resulting in an impressive energy conservation of 50.2%and a notable 24.2%reduction in carbon emissions.The ultra-deep sustained water injection of 100 m^(3)·h^(-1)in a single well would not rupture the formation or cause water leakage,and 7.87×10^(5)t of mine water could be effectively stored in the Liujiagou Formation,presenting a viable method for mine-water management in the Ordos Basin and providing insights for green and low-carbon mining. 展开更多
关键词 Dual carbon targets Coal-water-thermal co-mining Ecologically fragile areas Mine-water control Resource utilization
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Correlation of periodontal inflamed surface area with glycated hemoglobin,interleukin-6 and lipoprotein(a)in type 2 diabetes with retinopathy 被引量:3
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作者 Nusreen Jamal Thazhe Poyil Rosamma Joseph Vadakkekuttical Chandni Radhakrishnan 《World Journal of Diabetes》 SCIE 2024年第4期686-696,共11页
BACKGROUND The two-way relationship between periodontitis and type 2 diabetes mellitus(T2DM)is well established.Prolonged hyperglycemia contributes to increased periodontal destruction and severe periodontitis,accentu... BACKGROUND The two-way relationship between periodontitis and type 2 diabetes mellitus(T2DM)is well established.Prolonged hyperglycemia contributes to increased periodontal destruction and severe periodontitis,accentuating diabetic complications.An inflammatory link exists between diabetic retinopathy(DR)and periodontitis,but the studies regarding this association and the role of lipoprotein(a)[Lp(a)]and interleukin-6(IL-6)in these conditions are scarce in the literature.AIM To determine the correlation of periodontal inflamed surface area(PISA)with glycated Hb(HbA1c),serum IL-6 and Lp(a)in T2DM subjects with retinopathy.METHODS This cross-sectional study comprised 40 T2DM subjects with DR and 40 T2DM subjects without DR.All subjects were assessed for periodontal parameters[bleeding on probing(BOP),probing pocket depth,clinical attachment loss(CAL),oral hygiene index-simplified,plaque index(PI)and PISA],and systemic parameters[HbA1c,fasting plasma glucose and postprandial plasma glucose,fasting lipid profile,serum IL-6 and serum Lp(a)].RESULTS The proportion of periodontitis in T2DM with and without DR was 47.5%and 27.5%respectively.Severity of periodontitis,CAL,PISA,IL-6 and Lp(a)were higher in T2DM with DR group compared to T2DM without DR group.Significant difference was observed in the mean percentage of sites with BOP between T2DM with DR(69%)and T2DM without DR(41%),but there was no significant difference in PI(P>0.05).HbA1c was positively correlated with CAL(r=0.351,P=0.001),and PISA(r=0.393,P≤0.001)in study subjects.A positive correlation was found between PISA and IL-6(r=0.651,P<0.0001);PISA and Lp(a)(r=0.59,P<0.001);CAL and IL-6(r=0.527,P<0.0001)and CAL and Lp(a)(r=0.631,P<0.001)among study subjects.CONCLUSION Despite both groups having poor glycemic control and comparable plaque scores,the periodontal parameters were higher in DR as compared to T2DM without DR.Since a bidirectional link exists between periodontitis and DM,the presence of DR may have contributed to the severity of periodontal destruction and periodontitis may have influenced the progression of DR. 展开更多
关键词 Type 2 diabetes mellitus PERIODONTITIS Periodontal inflamed surface area Glycated Hb Diabetic retinopathy
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Research on the Relationship Between Environmental and Economic Coupling Systems in Bohai Bay Area Based on a Vector Autoregression(VAR)Model 被引量:1
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作者 CAO Huimin WANG Ping +2 位作者 ZHANG Surong XU Dongpo TIAN Weijun 《Journal of Ocean University of China》 CAS CSCD 2024年第2期557-566,共10页
This study analyzed the impact of land-based contaminants and tertiary industrial structure on economic development in the selected Bohai Bay area,China.Based on panel data spanning 2011-2020,a vector autoregressive(V... This study analyzed the impact of land-based contaminants and tertiary industrial structure on economic development in the selected Bohai Bay area,China.Based on panel data spanning 2011-2020,a vector autoregressive(VAR)model is used to analyze and forecast the short-run and long-run relationships between three industrial structures,pollutant discharge,and economic development.The results showed that the environmental index had a long-term cointegration relationship with the industrial structure economic index.Per capital chemical oxygen demand(PCOD)and per capita ammonia nitrogen(PNH_(3)N)had a positive impact on delta per capita GDP(dPGDP),while per capita solid waste(PSW),the secondary industry rate(SIR)and delta tertiary industry(dTIR)had a negative impact on dPGDP.The VAR model under this coupling system had stability and credibility.The impulse response results showed that the short-term effect of the coupling system on dPGDP was basically consistent with the Granger causality test results.In addition,variance decomposition was used in this study to predict the long-term impact of the coupling system in the next ten periods(i.e.,ten years).It was found that dTIR had a great impact on dPGDP,with a contribution rate as high as 74.35%in the tenth period,followed by the contribution rate of PCOD up to 3.94%,while the long-term contribution rates of PSW,SIR and PNH3N were all less than 1%.The results show that the government should support the development of the tertiary industry to maintain the vitality of economic development and prevent environmental deterioration. 展开更多
关键词 Bohai Bay area environmental pollution industrial structure cointegration theory VAR model impulse response
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Seismic response of a mid-story isolated structure considering SSI in mountainous areas under long-period earthquakes 被引量:1
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作者 Wan Feng Qin Shengwu +7 位作者 Liu Dewen Zhao Tiange Zheng Yanping Shan Hang Li Zhiang Peng Fusong Xu Jingran Lei Min 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第1期151-161,共11页
At present,there is not much research on mid-story isolated structures in mountainous areas.In this study,a model of a mid-story isolated structure considering soil-structure interaction(SSI)in mountainous areas is es... At present,there is not much research on mid-story isolated structures in mountainous areas.In this study,a model of a mid-story isolated structure considering soil-structure interaction(SSI)in mountainous areas is established along with a model that does not consider SSI.Eight long-period earthquake waves and two ordinary earthquake waves are selected as inputs for the dynamic time history analysis of the structure.The results show that the seismic response of a mid-story isolated structure considering SSI in mountainous areas can be amplified when compared with a structure that does not consider SSI.The structure response under long-period earthquakes is larger than that of ordinary earthquakes.The structure response under far-field harmonic-like earthquakes is larger than that of near-fault pulse-type earthquakes.The structure response under near-fault pulse-type earthquakes is larger than that of far-field non-harmonic earthquakes.When subjected to long-period earthquakes,the displacement of the isolated bearings exceeded the limit value,which led to instability and overturning of the structure.The structure with dampers in the isolated story could adequately control the nonlinear response of the structure,effectively reduce the displacement of the isolated bearings,and provide a convenient,efficient and economic method not only for new construction but also to retrofit existing structures. 展开更多
关键词 SSI in mountainous areas long-period earthquakes mid-story isolated structure structural dynamic analysis
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Diversity of Orchids in Terms of Their Distribution, Uses and Conservation in Annapurna Conservation Area of Nepal
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作者 Babu Lal Tiruwa Basu Dev Neupane +2 位作者 Rabin Kadariya Chiranjibi Prasad Pokheral Bijaya Pant 《American Journal of Plant Sciences》 CAS 2024年第6期422-440,共19页
The Annapurna Conservation Area (ACA), the first conservation area and the largest protected area (PA) in Nepal, is incredibly rich in biodiversity. Notwithstanding this, orchids in the ACA have not been explored enou... The Annapurna Conservation Area (ACA), the first conservation area and the largest protected area (PA) in Nepal, is incredibly rich in biodiversity. Notwithstanding this, orchids in the ACA have not been explored enough yet thus making the need for ambitious research to be carried out. Previous study only included 81 species of orchids within ACA. This study aims to update the record of species and genera richness in the ACA. In total 198 species of orchids, belonging to 67 genera (40% and 62% of the total recorded orchid species and genera in Nepal) has been recorded in ACA. This represents an increase of 144% in species and 56% in genera over the previous data. Out of the 198 species, 99 were epiphytes, 6 were holomycotrophic and 93 were terrestrial. Among the 67 genera, Bulbophyllum (17) species were dominant, followed by Dendrobium (16), Herminium (10), Coelogyne, Plantanthera (9 each), Eria, Habenaria, Oberonia (8 each), Calanthe (7), and Liparis (6). Fifty-six species were found to be ornamentally significant and 85 species medicinally significant. 展开更多
关键词 ORCHIDS Annapurna Conservation area DIVERSITY DISTRIBUTION USES
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The environmental analysis and site selection of mussel and large yellow croaker aquaculture areas based on high resolution remote sensing
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作者 Lina Cai Jie Yin +3 位作者 Xiaojun Yan Yongdong Zhou Rong Tang Menghan Yu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第3期66-86,共21页
Mussel aquaculture and large yellow croaker aquaculture areas and their environmental characteristics in Zhoushan were analyzed using satellite data and in-situ surveys.A new two-step remote sensing method was propose... Mussel aquaculture and large yellow croaker aquaculture areas and their environmental characteristics in Zhoushan were analyzed using satellite data and in-situ surveys.A new two-step remote sensing method was proposed and applied to determine the basic environmental characteristics of the best mussel and large yellow croaker aquaculture areas.This methodology includes the first step of extraction of the location distribution and the second step of the extraction of internal environmental factors.The fishery ranching index(FRI1,FRI2)was established to extract the mussel and the large yellow croaker aquaculture area in Zhoushan,using Gaofen-1(GF-1)and Gaofen-6(GF-6)satellite data with a special resolution of 2 m.In the second step,the environmental factors such as sea surface temperature(SST),chlorophyll a(Chl-a)concentration,current and tide,suspended sediment concentration(SSC)in mussel aquaculture area and large yellow croaker aquaculture area were extracted and analyzed in detail.The results show the following three points.(1)For the extraction of the mussel aquaculture area,FRI1 and FRI2 are complementary,and the combination of FRI1 and FRI2 is suitable to extract the mussel aquaculture area.As for the large yellow croaker aquaculture area extraction,FRI2 is suitable.(2)Mussel aquaculture and the large yellow croaker aquaculture area in Zhoushan are mainly located on the side near the islands that are away from the eastern open waters.The water environment factor template suitable for mussel and large yellow croaker aquaculture was determined.(3)This two-step remote sensing method can be used for the preliminary screening of potential site selection for the mussels and large yellow croaker aquaculture area in the future.the fishery ranching index(FRI1,FRI2)in this paper can be applied to extract the mussel and large yellow croaker aquaculture areas in coastal waters around the world. 展开更多
关键词 mussel aquaculture area large yellow croaker aquaculture area high resolution satellite site selection environmental analysis
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Prevalence of Malnutrition and Anaemia in Children ≤ 5 Years of Age in Some Conflict Hit Areas of Meme Division of the South West Region of Cameroon
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作者 Asoba Gillian Nkeudem Ebong Fidelis Sameh +3 位作者 Samuel Metuge Teh Rene Ning Ngede Laura Senge Sumbele Irene Ngole 《Food and Nutrition Sciences》 CAS 2024年第4期235-244,共10页
Malnutrition refers to the deficiency, imbalances, or excesses in a person’s intake of energy or nutrients [1]. Khan defines anaemia as below level of Haemoglobin in red blood shown by a lower number of functioning r... Malnutrition refers to the deficiency, imbalances, or excesses in a person’s intake of energy or nutrients [1]. Khan defines anaemia as below level of Haemoglobin in red blood shown by a lower number of functioning red blood cells [2]. The crisis in the North West and South West Regions of Cameroon has led to several negative effects on children’s living conditions. There has been an increase in malnutrition and anaemia in the South West Region and Kumba in particular. The main objective of this study was “to examine the prevalence of malnutrition and anaemia in children ≤ 5 years of age in some conflict-hit areas of Meme Division”. A descriptive cross-sectional study was conducted in 2023 from March to June. We recruited 200 children ≤ 5 years into the study from three hospitals. The regional hospital annex in Kumba, Presbyterian General Hospital Kumba and the Ntam Hospital in Kumba. Socio-demographic factors were assessed using questionnaire, nutritional status was assessed by the use anthropometric measurements and an auto haematology analyser was used to determine anaemia. The overall prevalence of malnutrition in the study area was 40.5%. The prevalence of malnutrition varied significantly (P < 0.001) with the study sites. The overall prevalence of anaemia in the study area was 70.5%. The prevalence of anaemia was not significantly associated with the study sites. The prevalence of Malnutrition and Anaemia in children ≤ 5 years of age is very high in the Kumba municipalities. This could be attributed to the ongoing crisis which has caused a lot of social migrations from rural areas to Urban areas which are safer. 展开更多
关键词 MALNUTRITION ANAEMIA PREVALENCE Conflict Hit areas
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Exploring well-being disparities between urban and rural areas:A case study in the Stavropol Territory,Russia
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作者 Anastasia CHAPLITSKAYA Wim HEIJMAN Johan van OPHEM 《Regional Sustainability》 2024年第1期80-92,共13页
Rural areas are crucial for a country’s sustainable economy.New strategies are needed to develop rural areas to improve the well-being of rural population and generate new job opportunities.This is especially importa... Rural areas are crucial for a country’s sustainable economy.New strategies are needed to develop rural areas to improve the well-being of rural population and generate new job opportunities.This is especially important in countries where agricultural production accounts for a significant share of the gross product,such as Russia.In this study,we identified the key indicators of satisfaction and differences between rural and urban citizens based on their social,economic,and environmental backgrounds,and determined whether there are well-being disparities between rural and urban areas in the Stavropol Territory,Russia.We collected primary data through a survey based on the European Social Survey framework to investigate the potential differences between rural and urban areas.By computing the regional well-being index using principal component analysis,we found that there was no statistically significant difference in well-being between rural and urban areas.Results of key indicators showed that rural residents felt psychologically more comfortable and safer,assessed their family relationships better,and adhered more to traditions and customs.However,urban residents showed better economic and social conditions(e.g.,infrastructures,medical care,education,and Internet access).The results of this study imply that we can better understand the local needs,advantages,and unique qualities,thereby gaining insight into the effectiveness of government programs.Policy-makers and local authorities can consider targeted interventions based on the findings of this study and strive to enhance the well-being of both urban and rural residents. 展开更多
关键词 WELL-BEING Sustainable development Rural areas Urban areas Principal component analysis(PCA) RUSSIA
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Glacier area change (1993-2019) and its relationship to debris cover, proglacial lakes, and morphological parameters in the Chandra-Bhaga Basin, Western Himalaya, India
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作者 VATSAL Sarvagya AZAM Mohd Farooq +5 位作者 BHARDWAJ Anshuman MANDAL Arindan BAHUGUNA Ishmohan RAMANATHAN Alagappan RAJU N.Janardhana TOMAR Sangita Singh 《Journal of Mountain Science》 SCIE CSCD 2024年第4期1287-1306,共20页
Glacier inventories serve as critical baseline data for understanding the impacts of climate change on glaciers.The present study maps the outlines of glaciers in the Chandra-Bhaga Basin(western Himalaya)for the years... Glacier inventories serve as critical baseline data for understanding the impacts of climate change on glaciers.The present study maps the outlines of glaciers in the Chandra-Bhaga Basin(western Himalaya)for the years 1993,2000,2010,and 2019 using Landsat Thematic Mapper(TM),Enhanced Thematic Mapper(ETM),and Operational Land Imager(OLI)datasets.A total of 251 glaciers,each having an area above 0.5 km^(2),were identified,which include 216 clean-ice and 35 debris-covered glaciers.Area changes are estimated for three periods:1993-2000,2000-2010,and 2010-2019.The total glacierized area was 996±62 km^(2) in 1993,which decreased to 973±70 km^(2) in 2019.The mean rate of glacier area loss was higher in the recent decade(2010-2019),at 0.036 km^(2),compared to previous decades(0.029 km^(2) in 2000-2010 and 0.025 km^(2) in 1993-2000).Supraglacial debris cover changes are also mapped over the period of 1993 and 2019.It is found that the supraglacial debris cover increased by 14.12±2.54 km^(2)(15.2%)during 1993-2019.Extensive field surveys on Chhota Shigri,Panchi II,Patsio,Hamtah,Mulkila,and Yoche Lungpa glaciers were carried out to validate the glacier outlines and supraglacial debris cover estimated using satellite datasets.Controls of various morphological parameters on retreat were also analyzed.It is observed that small,clean ice,south oriented glaciers,and glaciers with proglacial lakes are losing area at faster rates than other glaciers in the basin. 展开更多
关键词 GLACIER area change Debris cover MORPHOLOGY Proglacial lake
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Acetylacetone-TiO_(2) Promoted Large Area Compatible Cascade Electron Transport Bilayer for Efficient Perovskite Solar Cells
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作者 Hyong Joon Lee Jin Kyoung Park +1 位作者 Jin Hyuck Heo Sang Hyuk Im 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第2期221-228,共8页
In designing efficient perovskite solar cells(PSCs),the selection of suitable electron transport layers(ETLs)is critical to the final device performance as they determine the driving force for selective charge extract... In designing efficient perovskite solar cells(PSCs),the selection of suitable electron transport layers(ETLs)is critical to the final device performance as they determine the driving force for selective charge extraction.SnO_(2)nanoparticles(NPs)based ETLs have been a popular choice for PSCs due to superior electron mobility,but their relatively deep-lying conduction band energy levels(ECB)result in substantial potential loss.Meanwhile,TiO_(2)NPs establish favorable band alignment owing to shallower ECB,but their low intrinsic mobility and abundant surface trap sites impede the final performance.For this reason,constructing a cascaded bilayer ETL is highly desirable for efficient PSCs,as it can rearrange energy levels and exploit on advantages of an individual ETL.In this study,we prepare SnO_(2)NPs and acetylacetone-modified TiO_(2)(Acac-TiO_(2))NPs and implement them as bilayer SnO_(2)/Acac-TiO_(2)(BST)ETL,to assemble cascaded energy band structure.SnO_(2)contributes to rapid charge carrier transport from high electron mobility while Acac-TiO_(2)minimizes band-offset and effectively suppresses interfacial recombination.Accordingly,the optimized BST ETL generates synergistic influence and delivers power conversion efficiency(PCE)as high as 23.14%with open-circuit voltage(V_(oc))reaching 1.14 V.Furthermore,the BST ETL is transferred to a large scale and the corresponding mini module demonstrates peak performance of 18.39%PCE from 25 cm^(2)aperture area.Finally,the BST-based mini module exhibit excellent stability,maintaining 83.1%of its initial efficiency after 1000 h under simultaneous 1 Sun light-soaking and damp heat(85℃/RH 85%)environment. 展开更多
关键词 ACETYLACETONE large area PEROVSKITE solar cells TiO_(2)
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Geographical Accessibility to Basic Infrastructures and Services in Rural Senegal: The Case of the Niakhar Area
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作者 Alphousseyni Ndonky Soda Loum Mouhamadou Moustapha Mbacké Ndour 《Journal of Geographic Information System》 2024年第5期343-366,共24页
Access to basic infrastructure and services is a factor in economic development and an important aspect in combatting social and spatial disparities. But this access is often subject to several constraints, including ... Access to basic infrastructure and services is a factor in economic development and an important aspect in combatting social and spatial disparities. But this access is often subject to several constraints, including geographical accessibility. In this article, we aim to analyze the geographical accessibility to basic infrastructure and services in the Niakhar area, using the improved two step floating catchment area method and local spatial association indicators. The results reveal that the areas with high accessibility to health and education infrastructures and services are mainly located along the south-east and north-west gradient, while those with low accessibility are found in the south-west and north-east center. They also show high accessibility to trade services in the center of the study area. 展开更多
关键词 Two-Stage Floating areas Spatial Disparities Local Spatial Association Indicators
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Food Hygiene and Safety Practices amongst Food Vendors in the Western Area, Sierra Leone
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作者 Philip John Kanu Hamid Turay 《Food and Nutrition Sciences》 CAS 2024年第6期421-431,共11页
Food safety and hygiene practices require a multisectoral approach including food, water, sanitation, waste management, transport, education, trade, policies and programs that enable safe food preparation, storage and... Food safety and hygiene practices require a multisectoral approach including food, water, sanitation, waste management, transport, education, trade, policies and programs that enable safe food preparation, storage and service. Unsafe food can cause illness keeping people from achieving their full potential and death. This was a descriptive study that uses a mixed method approach to derive insights into the characteristics of food vendors related to demography, knowledge, practices, infrastructure, compliance and recommendation for a policymaking framework. Using the Lemeshows’ sample size formula, 473 vendors from formal (restaurants) and informal (cookri-baffa/table top) sites were interviewed and observed. We found from discussions that respondents had a good understanding on how to keep food safe. However, observed practices were poor 93% handled food with their bare hands, 83% did not cover their hair, and 76% did not wear an apron whilst handling, preparing or serving food, 61% did not keep their finger nails clean or short and 57% did not wash their hand before preparing or serving food. Over half (51%) had access to a toilet but 32% reported their use required payment and emphasized their poor condition/inadequate management. Nearly half (47%) of the vending sites did not have a handwashing facility, with soap and water available. Only 7% reported having any authority oversight of food safety. Food safety and hygiene practices in most cookri shops and restaurants was ‘poor’ with very limited surveillance system in place by competent authorities for compliance of food operators. Hand washing, clean surroundings, and covered food were the most common and emphasized practices to mitigate the risks associated with unsafe food. 展开更多
关键词 Food Safety and Hygiene Formal and Informal Food Vendors Western area Sierra Leone
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Identified the hydrochemical and the sulfur cycle process in subsidence area of Pingyu mining area using multi-isotopes combined with hydrochemistry methods
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作者 Hui-Meng Su Fa-Wang Zhang +4 位作者 Jing-Yu Hu Jin-Feng Lei Wei Zuo Bo Yang Yu-Hua Liu 《Journal of Groundwater Science and Engineering》 2024年第1期62-77,共16页
Groundwater serves as an important water source for residents in and around mining areas.To achieve scientific planning and efficient utilization of water resources in mining areas,it is essential to figure out the ch... Groundwater serves as an important water source for residents in and around mining areas.To achieve scientific planning and efficient utilization of water resources in mining areas,it is essential to figure out the chemical formation process and the ground water sulfur cycle that transpire after the coal mining activities.Based on studies of hydrochemistry and D,^(18)O-H_(2)O,^(34)S-SO_(4)isotopes,this study applied principal component analysis,ion ratio and other methods in its attempts to reveal the hydrogeochemical action and sulfur cycle in the subsidence area of Pingyu mining area.The study discovered that,in the studied area,precipitation provides the major supply of groundwater and the main water chemistry effects are dominated by oxidation dissolution of sulfide minerals as well as the dissolution of carbonate and silicate rocks.The sulfate in groundwater primarily originates from oxidation and dissolution of sulfide minerals in coal-bearing strata and human activities.The mixed sulfate formed by the oxidation of sulfide minerals and by human activities continuously recharges the groundwater,promoting the dissolution of carbonate rock and silicate rock in the process. 展开更多
关键词 PCA Ion ratio Water chemistry Sulfide minerals Multi-isotopes Subsidence area of mining area
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Impact of climate change and human activities on the spatiotemporal dynamics of surface water area in Gansu Province, China
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作者 LU Haitian ZHAO Ruifeng +3 位作者 ZHAO Liu LIU Jiaxin LYU Binyang YANG Xinyue 《Journal of Arid Land》 SCIE CSCD 2024年第6期798-815,共18页
Understanding the dynamics of surface water area and their drivers is crucial for human survival and ecosystem stability in inland arid and semi-arid areas.This study took Gansu Province,China,a typical area with comp... Understanding the dynamics of surface water area and their drivers is crucial for human survival and ecosystem stability in inland arid and semi-arid areas.This study took Gansu Province,China,a typical area with complex terrain and variable climate,as the research subject.Based on Google Earth Engine,we used Landsat data and the Open-surface Water Detection Method with Enhanced Impurity Control method to monitor the spatiotemporal dynamics of surface water area in Gansu Province from 1985 to 2022,and quantitatively analyzed the main causes of regional differences in surface water area.The findings revealed that surface water area in Gansu Province expanded by 406.88 km2 from 1985 to 2022.Seasonal surface water area exhibited significant fluctuations,while permanent surface water area showed a steady increase.Notably,terrestrial water storage exhibited a trend of first decreasing and then increasing,correlated with the dynamics of surface water area.Climate change and human activities jointly affected surface hydrological processes,with the impact of climate change being slightly higher than that of human activities.Spatially,climate change affected the'source'of surface water to a greater extent,while human activities tended to affect the'destination'of surface water.Challenges of surface water resources faced by inland arid and semi-arid areas like Gansu Province are multifaceted.Therefore,we summarized the surface hydrology patterns typical in inland arid and semi-arid areas and tailored surface water'supply-demand'balance strategies.The study not only sheds light on the dynamics of surface water area in Gansu Province,but also offers valuable insights for ecological protection and surface water resource management in inland arid and semi-arid areas facing water scarcity. 展开更多
关键词 surface water area terrestrial water storage Open-surface Water Detection Method with Enhanced Impurity Control method Google Earth Engine climate change human activities inland arid and semi-arid areas
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Quantifying the impact of earthquakes and geological factors on spatial heterogeneity of debris-flow prone areas:A case study in the Hengduan Mountains
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作者 HU Xudong SHEN Yitong +6 位作者 HU Kaiheng XU Wennian LIU Daxiang HE Songtang GAO Jiazhen WEI Li LIU Shuang 《Journal of Mountain Science》 SCIE CSCD 2024年第5期1522-1533,共12页
Understanding the spatial heterogeneity of debris-flow-prone areas holds significant implications for regional risk management, particularly in seismically active regions with geological faults. Despite the significan... Understanding the spatial heterogeneity of debris-flow-prone areas holds significant implications for regional risk management, particularly in seismically active regions with geological faults. Despite the significance of this knowledge, a comprehensive quantification of the influence of regional topographical and geological factors on the spatial heterogeneity of debris-flow-prone areas has been lacking. This study selected the Hengduan Mountains, an earthquake-prone region characterized by diverse surface conditions and complex landforms, as a representative study area. An improved units zoning and objective factors identification methodology was employed in earthquake and fault analysis to assess the impact of seismic activity and geological factors on spatial heterogeneity of debrisflow prone areas. Results showed that the application of GIS technology with hydrodynamic intensity and geographical units analysis can effectively analyze debris-flow prone areas. Meanwhile, earthquake and fault zones obviously increase the density of debrisflow prone catchments and make them unevenly distributed. The number of debris-flow prone areas shows a nonlinear variation with the gradual increase of geomorphic factor value. Specifically, the area with 1000 m-2500 m elevation difference, 25°-30° average slope, and 0.13-0.15 land use index is the most favorable conditions for debris-flow occurrence;The average annual rainfall from 600 to 1150 mm and landslides gradient from 16° to 35° are the main causal factors to trigger debris flow. Our study sheds light on the quantification of spatial heterogeneity in debris flow-prone areas in earthquake-prone regions, which can offer crucial support for post-debris flow risk management strategies. 展开更多
关键词 debris-flow prone areas causal factors GIS-based method spatial heterogeneity Hengduan Mountains
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Impact of typical environments in China’s western mountainous areas on the durability of railway concrete:a review
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作者 Jiahe Wang Yanbin Tan +3 位作者 Huajian Li Xinhua Zhong Jiaxuan Wang Yu Gao China 《Railway Sciences》 2024年第5期650-669,共20页
Purpose–This study aims to analyze the impact mechanism of typical environments in China’s western mountainous areas on the durability of railway concrete and propose measures to improve durability.Design/methodolog... Purpose–This study aims to analyze the impact mechanism of typical environments in China’s western mountainous areas on the durability of railway concrete and propose measures to improve durability.Design/methodology/approach–With the continuous promotion of infrastructure construction,the focus of China’s railway construction has gradually shifted to the western region.The four typical environments of large temperature differences,strong winds and dryness,high cold and low air pressure unique to the western mountainous areas of China have adverse effects on the durability of typical railway structure concrete(bridges,ballastless tracks and tunnels).This study identified the characteristics of four typical environments in the western mountainous areas of China through on-site research.The impact mechanism of the four typical environments on the durability of concrete in different structural parts of railways has been explored through theoretical analysis and experimental research;Finally,a strategy for improving the durability of railway concrete suitable for the western mountainous areas of China was proposed.Findings–The daily temperature difference in the western mountainous areas of China is more than twice that of the plain region,which will lead to significant temperature deformation and stress in the multi-layered structure of railway ballastless tracks.It will result in cracking.The wind speed in the western plateau region is about 2.5 to 3 times that of the plain region,and the average annual rainfall is only 1/5 of that in the plain region.The drying effect on the surface of casting concrete will significantly accelerate its cracking process,leading to serious durability problems.The environmental temperature in the western mountainous areas of China is generally low,and there are more freeze-thaw cycles,which will increase the risk of freeze-thaw damage to railway concrete.The environmental air pressure in the western plateau region is only 60%of that in the plain region.The moisture inside the concrete is more likely to diffuse into the surrounding environment under the pressure difference,resulting in greater water loss and shrinkage deformation of the concrete in the plateau region.The above four issues will collectively lead to the rapid deterioration of concrete durability in the western plateau region.The corresponding durability improvement suggestions from theoretical research,new technology development and standard system was proposed in this paper.Originality/value–The research can provide the mechanism of durability degradation of railway concrete in the western mountainous areas of China and corresponding improvement strategies. 展开更多
关键词 Western mountainous areas CONCRETE DURABILITY ENVIRONMENT
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