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Simulation Research on Structure Changing Control over the Follow Up System of the Smart Mine
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作者 李杰 王琳 +1 位作者 孟嘉友 李世义 《Journal of Beijing Institute of Technology》 EI CAS 2000年第3期278-282,共5页
By analyzing the target's motion pattern, in terms of the requirement for the performance indexes of the follow up system, the structure changing control and time optimal theory is proposed. The system's co... By analyzing the target's motion pattern, in terms of the requirement for the performance indexes of the follow up system, the structure changing control and time optimal theory is proposed. The system's control scheme from three different aspects(the dynamic response simulation, compound control simulation and dynamic tracking simulation) is also studied. And all the results proved the feasibility of the synthetical utilization of the open loop control, speed decreased control and position closed loop control. 展开更多
关键词 structure changing control compound control CONTROLLER system analysis simulation
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Plastid phylogenomics provides new insights into the systematics,diversification,and biogeography of Cymbidium(Orchidaceae) 被引量:1
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作者 Hai-Yao Chen Zhi-Rong Zhang +7 位作者 Xin Yao Ji-Dong Ya Xiao-Hua Jin Lin Wang Lu Lu De-Zhu Li Jun-Bo Yang Wen-Bin Yu 《Plant Diversity》 SCIE CAS CSCD 2024年第4期448-461,共14页
Cymbidium(Orchidaceae:Epidendroideae),with around 60 species,is widely-distributed across Southeast Asia,providing a nice system for studying the processes that underlie patterns of biodiversity in the region.However,... Cymbidium(Orchidaceae:Epidendroideae),with around 60 species,is widely-distributed across Southeast Asia,providing a nice system for studying the processes that underlie patterns of biodiversity in the region.However,phylogenetic relationships of Cymbidium have not been well resolved,hampering investigations of species diversification and the biogeographical history of this genus.In this study,we construct a plastome phylogeny of 56 Cymbidium species,with four well-resolved major clades,which provides a framework for biogeographical and diversification rate analyses.Molecular dating and biogeographical analyses show that Cymbidium likely originated in the region spanning northern IndoBurma to the eastern Himalayas during the early Miocene(~21.10 Ma).It then rapidly diversified into four major clades in East Asia within approximately a million years during the middle Miocene.Cymbidium spp.migration to the adjacent regions(Borneo,Philippines,and Sulawesi)primarily occurred during the Pliocene-Pleistocene period.Our analyses indicate that the net diversification rate of Cymbidium has decreased since its origin,and is positively associated with changes in temperature and monsoon intensity.Favorable hydrothermal conditions brought by monsoon intensification in the early Miocene possibly contributed to the initial rapid diversification,after which the net diversification rate was reduced with the cooling climate after the middle Miocene.The transition from epiphytic to terrestrial habits may have enabled adaptation to cooler environments and colonization of northern niches,yet without a significant effect on diversification rates.This study provides new insights into how monsoon activity and temperature changes affected the diversification dynamics of plants in Southeast Asia. 展开更多
关键词 CYMBIDIUM East Asia Asian monsoons Climate change Biogeographical patterns
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Spatiotemporal Variability and Environmental Controls of Temperature Sensitivity of Ecosystem Respiration across the Tibetan Plateau
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作者 Danrui SHENG Xianhong MENG +8 位作者 Shaoying WANG Zhaoguo LI Lunyu SHANG Hao CHEN Lin ZHAO Mingshan DENG Hanlin NIU Pengfei XU Xiaohu WEN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第9期1821-1842,共22页
Warming-induced carbon loss via ecosystem respiration(R_(e))is probably intensifying in the alpine grassland ecosystem of the Tibetan Plateau owing to more accelerated warming and the higher temperature sensitivity of... Warming-induced carbon loss via ecosystem respiration(R_(e))is probably intensifying in the alpine grassland ecosystem of the Tibetan Plateau owing to more accelerated warming and the higher temperature sensitivity of R_(e)(Q_(10)).However,little is known about the patterns and controlling factors of Q_(10)on the plateau,impeding the comprehension of the intensity of terrestrial carbon-climate feedbacks for these sensitive and vulnerable ecosystems.Here,we synthesized and analyzed multiyear observations from 14 sites to systematically compare the spatiotemporal variations of Q_(10)values in diverse climate zones and ecosystems,and further explore the relationships between Q_(10)and environmental factors.Moreover,structural equation modeling was utilized to identify the direct and indirect factors predicting Q_(10)values during the annual,growing,and non-growing seasons.The results indicated that the estimated Q_(10)values were strongly dependent on temperature,generally,with the average Q_(10)during different time periods increasing with air temperature and soil temperature at different measurement depths(5 cm,10 cm,20 cm).The Q_(10)values differentiated among ecosystems and climatic zones,with warming-induced Q_(10)declines being stronger in colder regions than elsewhere based on spatial patterns.NDVI was the most cardinal factor in predicting annual Q_(10)values,significantly and positively correlated with Q_(10).Soil temperature(Ts)was identified as the other powerful predictor for Q_(10),and the negative Q_(10)-Ts relationship demonstrates a larger terrestrial carbon loss potentiality in colder than in warmer regions in response to global warming.Note that the interpretations of the effect of soil moisture on Q_(10)were complicated,reflected in a significant positive relationship between Q_(10)and soil moisture during the growing season and a strong quadratic correlation between the two during the annual and non-growing season.These findings are conducive to improving our understanding of alpine grassland ecosystem carbon-climate feedbacks under warming climates. 展开更多
关键词 carbon cycle eddy covariance measurements ecosystem respiration Q_(10)value Tibetan Plateau climate change
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Thermodynamic theory of flotation for a complex multiphase solid -liquid system and high-entropy flotation
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作者 Shuming Wen 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第6期1177-1197,共21页
The flotation of complex solid–liquid multiphase systems involve interactions among multiple components,the core problem facing flotation theory.Meanwhile,the combined use of multicomponent flotation reagents to impr... The flotation of complex solid–liquid multiphase systems involve interactions among multiple components,the core problem facing flotation theory.Meanwhile,the combined use of multicomponent flotation reagents to improve mineral flotation has become an important issue in studies on the efficient use of refractory mineral resources.However,studying the flotation of complex solid–liquid systems is extremely difficult,and no systematic theory has been developed to date.In addition,the physical mechanism associated with combining reagents to improve the flotation effect has not been unified,which limits the development of flotation theory and the progress of flotation technology.In this study,we applied theoretical thermodynamics to a solid–liquid flotation system and used changes in the entropy and Gibbs free energy of the reagents adsorbed on the mineral surface to establish thermodynamic equilibrium equations that de-scribe interactions among various material components while also introducing adsorption equilibrium constants for the flotation reagents adsorbed on the mineral surface.The homogenization effect on the mineral surface in pulp solution was determined using the chemical potentials of the material components of the various mineral surfaces required to maintain balance.The flotation effect can be improved through synergy among multicomponent flotation reagents;its physical essence is the thermodynamic law that as the number of compon-ents of flotation reagents on the mineral surface increases,the surface adsorption entropy change increases,and the Gibbs free energy change of adsorption decreases.According to the results obtained using flotation thermodynamics theory,we established high-entropy flotation theory and a technical method in which increasing the types of flotation reagents adsorbed on the mineral surface,increasing the adsorption entropy change of the flotation reagents,decreasing the Gibbs free energy change,and improving the adsorption efficiency and stability of the flotation reagents improves refractory mineral flotation. 展开更多
关键词 multicomponent flotation reagent adsorption entropy change equations of thermodynamic equilibrium adsorption equilibri-um constant high-entropy flotation
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Enhanced entropy generation and heat transfer characteristics of magnetic nano-encapsulated phase change materials in latent heat thermal energy storage systems
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作者 P.S.REDDY P.SREEDEVI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第6期1051-1070,共20页
The objective of the current study is to investigate the importance of entropy generation and thermal radiation on the patterns of velocity,isentropic lines,and temperature contours within a thermal energy storage dev... The objective of the current study is to investigate the importance of entropy generation and thermal radiation on the patterns of velocity,isentropic lines,and temperature contours within a thermal energy storage device filled with magnetic nanoencapsulated phase change materials(NEPCMs).The versatile finite element method(FEM)is implemented to numerically solve the governing equations.The effects of various parameters,including the viscosity parameter,ranging from 1 to 3,the thermal conductivity parameter,ranging from 1 to 3,the Rayleigh parameter,ranging from 102 to 3×10^(2),the radiation number,ranging from 0.1 to 0.5,the fusion temperature,ranging from 1.0 to 1.2,the volume fraction of NEPCMs,ranging from 2%to 6%,the Stefan number,ranging from 1 to 5,the magnetic number,ranging from 0.1 to 0.5,and the irreversibility parameter,ranging from 0.1 to 0.5,are examined in detail on the temperature contours,isentropic lines,heat capacity ratio,and velocity fields.Furthermore,the heat transfer rates at both the cold and hot walls are analyzed,and the findings are presented graphically.The results indicate that the time taken by the NEPCMs to transition from solid to liquid is prolonged inside the chamber region as the fusion temperatureθf increases.Additionally,the contours of the heat capacity ratio Cr decrease with the increase in the Stefan number Ste. 展开更多
关键词 volume fraction of nano-encapsulated phase change material(NEPCM) RADIATION Stefan number heat capacity ratio entropy generation
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Impacts of multi-scenario land use change on ecosystem services and ecological security pattern: A case study of the Yellow River Delta
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作者 XueHua Cen Hua Zhang 《Research in Cold and Arid Regions》 CSCD 2024年第1期30-44,共15页
The Yellow River Delta(YRD), a critical economic zone along China's eastern coast, also functions as a vital ecological reserve in the lower Yellow River. Amidst rapid industrialization and urbanization, the regio... The Yellow River Delta(YRD), a critical economic zone along China's eastern coast, also functions as a vital ecological reserve in the lower Yellow River. Amidst rapid industrialization and urbanization, the region has witnessed significant land use/cover changes(LUCC), impacting ecosystem services(ES) and ecological security patterns(ESP). Investigating LUCC's effects on ES and ESP in the YRD is crucial for ecological security and sustainable development. This study utilized the PLUS model to simulate 2030 land use scenarios, including natural development(NDS), economic development(EDS), and ecological protection scenarios(EPS). Subsequently, the InVEST model and circuit theory were applied to assess ES and ESP under varying LUCC scenarios from 2010 to 2030. Findings indicate:(1) Notable LUCC from 2010 to 2030, marked by decreasing cropland and increasing construction land and water bodies.(2) From 2010 to 2020, improvements were observed in carbon storage,water yield, soil retention, and habitat quality, whereas 2020–2030 saw increases in water yield and soil retention but declines in habitat quality and carbon storage. Among the scenarios, EPS showed superior performance in all four ES.(3) Between 2010 and 2030, ecological sources, corridors, and pinchpoints expanded, displaying significant spatial heterogeneity. The EPS scenario yielded the most substantial increases in ecological sources,corridors, and pinchpoints, totaling 582.89 km^(2), 645.03 km^(2),and 64.43 km^(2), respectively. This study highlights the importance of EPS, offering insightful scientific guidance for the YRD's sustainable development. 展开更多
关键词 Land use change Multi-scenario simulation Ecosystem services Ecological security pattern the Yellow River Delta Circuit theory
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Exploring the Spatiotemporal Changes and Driving Forces of Ecosystem Services of Zhejiang Coasts,China,Under Sustainable Development Goals
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作者 ZHANG Shu SUN Chao +2 位作者 ZHANG Yixin HU Ming SHEN Xingru 《Chinese Geographical Science》 SCIE CSCD 2024年第4期647-661,共15页
Ecosystem services(ESs)refer to the continuous provisioning of ecosystem goods and services that benefit human beings.Over recent decades,rapid urbanization has exerted significant pressure on coastal ecosystems,resul... Ecosystem services(ESs)refer to the continuous provisioning of ecosystem goods and services that benefit human beings.Over recent decades,rapid urbanization has exerted significant pressure on coastal ecosystems,resulting in biodiversity and habitat loss,environmental pollution,and the depletion of natural resources.In response to these environmental challenges,the Sustainable Development Goals(SDGs)were proposed.Given the pressing need to address these issues,understanding the changes in ESs under the SDGs is crucial for formulating specific ecological strategies.In this study,we first analyzed land use and cover change in the Zhejiang coasts of China during 2000–2020.Then,we investigated the spatiotemporal configuration of ESs by integrating carbon storage(CS),soil retention(SR),habitat quality(HQ)and water yield(WY)using the Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model.The driving mechanisms of ESs,which varied by space and time,were also explored using the Geo-detector method.The results revealed that,over the past two decades:1)the Zhejiang coasts have experienced a significant increase of 2783.72 km^(2) in built-up land areas and a continuous decrease in farmland areas due to rapid urbanization;2)owing to higher precipitation,extensive vegetation cover,and reduced anthropogenic disturbances,forests emerge as a crucial land use type for maintaining ecosystem services such as HQ,CS,WY,and SR;3)ESs have generally declined across the entire Zhejiang coasts,with a significant decrease observed in the northern areas and an increase in the southern areas spatially;4)the expansion of built-up land areas emerged as the primary factor affecting ecosystem services,while the vegetation factor has been increasingly significant and is expected to become predominant in the near future.Our study provides insights of understanding of ecosystem service theory and emphasizing the importance of preserving biodiversity for long-term sustainable development,and valuable scientific references to support the ecological management decision-making for local governments. 展开更多
关键词 ecosystem services(ESs) Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model Geo-detector land use and cover change(LUCC) Zhejiang coasts China
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Response of ecosystem carbon storage to land use change from 1985 to 2050 in the Ningxia Section of Yellow River Basin,China
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作者 LIN Yanmin HU Zhirui +5 位作者 LI Wenhui CHEN Haonan WANG Fang NAN Xiongxiong YANG Xuelong ZHANG Wenjun 《Journal of Arid Land》 SCIE CSCD 2024年第1期110-130,共21页
Regional sustainable development necessitates a holistic understanding of spatiotemporal variations in ecosystem carbon storage(ECS),particularly in ecologically sensitive areas with arid and semi-arid climate.In this... Regional sustainable development necessitates a holistic understanding of spatiotemporal variations in ecosystem carbon storage(ECS),particularly in ecologically sensitive areas with arid and semi-arid climate.In this study,we calculated the ECS in the Ningxia Section of Yellow River Basin,China from 1985 to 2020 using the Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model based on land use data.We further predicted the spatial distribution of ECS in 2050 under four land use scenarios:natural development scenario(NDS),ecological protection scenario(EPS),cultivated land protection scenario(CPS),and urban development scenario(UDS)using the patch-generating land use simulation(PLUS)model,and quantified the influences of natural and human factors on the spatial differentiation of ECS using the geographical detector(Geodetector).Results showed that the total ECS of the study area initially increased from 1985 until reaching a peak at 402.36×10^(6) t in 2010,followed by a decreasing trend to 2050.The spatial distribution of ECS was characterized by high values in the eastern and southern parts of the study area,and low values in the western and northern parts.Between 1985 and 2020,land use changes occurred mainly through the expansion of cultivated land,woodland,and construction land at the expense of unused land.The total ECS in 2050 under different land use scenarios(ranked as EPS>CPS>NDS>UDS)would be lower than that in 2020.Nighttime light was the largest contributor to the spatial differentiation of ECS,with soil type and annual mean temperature being the major natural driving factors.Findings of this study could provide guidance on the ecological construction and high-quality development in arid and semi-arid areas. 展开更多
关键词 carbon storage land use change nighttime light Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model patch-generating land use simulation(PLUS)model geographical detector(Geodetector) Yellow River Basin
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Comparative Analysis for the Development of a Green Building Rating System for Nigeria
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作者 Usman Aminu Umar 《Journal of Civil Engineering and Architecture》 2024年第7期340-347,共8页
The functionality of buildings depends on the climate they are subjected to,this means buildings constructed these days need to be built to perform efficiently within the current and future climate and with the aim of... The functionality of buildings depends on the climate they are subjected to,this means buildings constructed these days need to be built to perform efficiently within the current and future climate and with the aim of reducing the greenhouse emission induced on the environment.In order to lower CO_(2) emissions and assist in reinforcing the capability of cities to adapt to climate change whilst enhancing the quality of the built environment,it is vital to improve the environmental performance and energy efficiency in buildings.This study aims to identify and compare existing GBRS(green building rating system)with Nigerian climatic condition.Proposal criteria weighting was developed from the questionnaire supplying expert opinions.It began with a comparative analysis of GBRS.The analysis was conducted to find the similarities and differences between existing rating systems and come up with an appropriate rating system for Nigeria.These approaches included a fieldwork approach(pilot study,survey);questionnaire;and interviews,both structured and unstructured.Then,the information generated in this pre-test investigation formed the conversational guide and described the decision to determine the main factors that should be involved in the new assessment system for Nigeria. 展开更多
关键词 Green building GBRS climate change NIGERIA
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A Systematic Literature Review of the Impact of Climate Change on Menopause: Altering the Age, Severity of Symptoms and Long-Term Effects
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作者 Vaidehi Chauhan Sameena Rahman 《Open Journal of Obstetrics and Gynecology》 2024年第7期1018-1026,共9页
Objective: This systematic review investigates the impact of climate change on menopause, focusing on the correlation between geographical location—considering altitude, temperature, humidity, and annual temperature ... Objective: This systematic review investigates the impact of climate change on menopause, focusing on the correlation between geographical location—considering altitude, temperature, humidity, and annual temperature range—and women’s menopausal experiences. This study aims to interpret how these environmental factors influence the age of onset, severity of symptoms such as hot flushes and night sweats, and other long-term effects of menopause. Understanding these relationships addresses a significant gap in current knowledge and could guide future public health strategies. Methods: Through a comprehensive analysis of three cross-continental studies involving 1500 postmenopausal women from Spain, South American countries (Ecuador, Panama, Chile), various climates in Türkiye (Black Sea, Mediterranean, Continental), and the United Arab Emirates (UAE), this review evaluates diverse environmental impacts. Studies were selected based on their methodological rigor, geographical diversity, and focus on the unique and personal experiences of menopause. Data was collected via questionnaires and routine medical checkups, analyzing demographic, lifestyle, mood, symptom severity, and onset age variables. Results: Preliminary analysis indicates that 52.5% of participants from Spanish-speaking countries and the UAE reported vasomotor symptoms, with those in higher temperatures and lower altitudes experiencing exacerbated symptoms. Notably, Mediterranean climates were associated with an earlier menopause onset. Seasonal changes had minimal impact across all regions, suggesting lifestyle and other environmental factors play a more significant role. Conclusions: The findings highlight a clear link between climate-related geographical factors and the menopausal experience. Women in warmer, lower-altitude regions suffer more severe symptoms, while those in Mediterranean climates face earlier onset. The absence of significant seasonal variations across the studies underscores the predominance of lifestyle and environmental factors over purely climatic conditions. These insights pave the way for targeted interventions and support the need for further public health research into the complex interactions between climate change and menopause. 展开更多
关键词 MENOPAUSE Climate Change Women’s Health PERIMENOPAUSE
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Changing Characteristics of Comfort Index of Human Body in Bengbu City in the Past 40 Years under the Background of Climate Change
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作者 Lei SHAN Xian ZHANG +2 位作者 Lei TIAN Ranran HE Jingyang CHEN 《Meteorological and Environmental Research》 2024年第2期40-43,共4页
Based on the daily meteorological data of Bengbu City during 1981-2020,the changing characteristics of three elements needed for the calculation of the comfort index of human body(CIHB)were discussed,and daily CIHB wa... Based on the daily meteorological data of Bengbu City during 1981-2020,the changing characteristics of three elements needed for the calculation of the comfort index of human body(CIHB)were discussed,and daily CIHB was classified and discussed.The results show that from 1981 to 2020,annual average temperature tended to increase significantly.Annual average wind speed and relative humidity showed a decreasing trend before 2011 but an increasing trend after 2011.The duration of the four seasons in Bengbu City mainly rose in spring,reduced in winter,declined first and then increased in summer,and rose first and then decreased in autumn.As CIHB was at grades 1 and 9(the most uncomfortable),the three factors had different effects on them.For cold weather,the influence of relative humidity and wind speed on CIHB can not be ignored besides temperature.In hot weather,the influence of temperature was dominant,and the change of annual average temperature could well correspond to the change in the number of very hot days.In the context of climate warming,the number of cold days tended to decline generally,but it was larger in the years with fewer very cold days.Under the background of climate warming,there was no obvious change in the number of days of the overall comfort of human body.The number of hot days was closely related to the duration of summer,and the number of days of grade 8 rose significantly in the years with an increase in the duration of summer. 展开更多
关键词 Climate change Human comfort Comfort index of human body(CIHB)
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Water quality changing trends of the Miyun Reservoir 被引量:6
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作者 王建平 程声通 贾海峰 《Journal of Southeast University(English Edition)》 EI CAS 2005年第2期215-219,共5页
In order to simulate changes in the water quality of the Miyun Reservoir dueto continuous descent of surface water level, a 3-D ecological hydrodynamic model was developedthrough coupling the water quality analysis si... In order to simulate changes in the water quality of the Miyun Reservoir dueto continuous descent of surface water level, a 3-D ecological hydrodynamic model was developedthrough coupling the water quality analysis simulation program (WASP) with the environmental fluiddynamics code (EFDC). The model was then calibrated and verified. Four scenarios (S1, S21, S22 andS23) were simulated using the model. Results show that the water quality of the Miyun Reservoirunder conditions of low surface water level is apparently affected by different amounts of inflowand different total phosphorus (TP) loadings. The chlorophyll-a concentration might exceed 10 μg/Lin many areas of the Miyun Reservoir (This limitative value is seen as a critical value ofeutrophication) when large loadings of TP enter due to the amount of inflow increasing. Results ofscenario S23 indicate that control of TP loadings can decrease chlorophyll-a concentrationeffectively, and the water quality of the Miyun Reservoir will improve or retain its status quo. 展开更多
关键词 water quality model hydrodynamic model scenario analysis changing trends
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Study on the Quantity Dynamic Changes of Heterobacteria and Vibrios in Larvae Industrialized Culture System 被引量:7
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作者 马妍 李健 +2 位作者 王斌 王群 刘淇 《Agricultural Science & Technology》 CAS 2008年第2期116-121,共6页
[ Objective ] The dynamic change of heterobacteria and vibrios in larvae industrialized culture system was studied to provide scientific reference for healthy cultivation of shrimp. [ Method ] The heterobacteria, vibr... [ Objective ] The dynamic change of heterobacteria and vibrios in larvae industrialized culture system was studied to provide scientific reference for healthy cultivation of shrimp. [ Method ] The heterobacteria, vibrios and pathogenic vibrio parahaemolyticus were monitored in larvae industrialized culture system. [ Result] The heterobacteria, vibrios and pathogenic vibrio parahaemolyticus were the most in fertilized eggs of shrimp but the least in nauplius, then their number would increase with growth. During whole rearing period, both boterobacteria in larvae, vibrios in water would increase by one order of magnitude, while both vibrios in larvae and heterobacteria in water would increase by two orders of magnitude. There were many heterobacteria and vibrios but few vibrio parahaemolyticus in living bait. The correlation coefficients between larvae and heterobacteria and vibrios in water were 0. 704 and 0. 840 in culture system respectively, while the correlation among heterobacteria, vibrios in living bait and larvae, water were weak or negative. [ Conclusion ] There was a dynamic relation between water and larvae in rearing period, and restrictly control of culture condition would restrain the occurrence of disease caused by vibrio parahaemolyticus, besides that bacteria number in bait was not obviously correlated with bacteria nubmer in culture system. 展开更多
关键词 Chinese shrimp larvae Heterotrophic bacteria VIBRIO Vibrio parahaemolyticus Dynamic change
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Changing Process and Impact Factors of Ecosystem in Shuangtaizi Estuary Wetland of China 被引量:1
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作者 王永洁 郑冬梅 罗金明 《Journal of Landscape Research》 2011年第5期45-48,51,共5页
By introducing geological and natural conditions of Shuangtaizi Estuary Wetland,a national nature reserve,and borrowing Landsat5 TM wetland data of the year 1987 and 2005,the core area of Shuangtaizi Estuary Wetland i... By introducing geological and natural conditions of Shuangtaizi Estuary Wetland,a national nature reserve,and borrowing Landsat5 TM wetland data of the year 1987 and 2005,the core area of Shuangtaizi Estuary Wetland is studied,areas of its natural water,mudflat,seepweed beach,culture zone,reservoir and swag,reed field,rice field and non-wetland landscape are respectively analyzed,as well as the changes of wetland community,water quality,waterfowl quantity and species.It is found that the study area is suffering from serious fragmentation of wetland,reducing reed yield,degrading water quality,decreasing bird species and amount,which implies that the degraded wetland environment has imposed threats on the survival of some wetland species.Root causes of such a result are analyzed from the perspectives of regional climate changes and human interventions;while regional climate changes include obvious temperature increase and precipitation decrease,human interventions include oil exploration,reclamation of land from the lake,overuse of biotic resources,environment pollution.Due to the interactive influence of these two factors,ecosystem of Shuangtaizi Estuary Wetland has experienced drastic changes,which should be attached sufficient importance by relevant departments so as to enhance its protection and management. 展开更多
关键词 WETLAND ECOsystem changing process IMPACT FACTORS Shuangtaizi ESTUARY WETLAND
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Establishment and validation of an adherence prediction system for lifestyle interventions in non-alcoholic fatty liver disease 被引量:6
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作者 Ming-Hui Zeng Qi-Yu Shi +1 位作者 Liang Xu Yu-Qiang Mi 《World Journal of Gastroenterology》 SCIE CAS 2024年第10期1393-1404,共12页
BACKGROUND Non-alcoholic fatty liver disease(NAFLD)is the most common liver disease worldwide,affecting about 1/4th of the global population and causing a huge global economic burden.To date,no drugs have been approve... BACKGROUND Non-alcoholic fatty liver disease(NAFLD)is the most common liver disease worldwide,affecting about 1/4th of the global population and causing a huge global economic burden.To date,no drugs have been approved for the treatment of NAFLD,making the correction of unhealthy lifestyles the principle method of treatment.Identifying patients with poor adherence to lifestyle correction and attempting to improve their adherence are therefore very important.AIM To develop and validate a scale that can rapidly assess the adherence of patients with NAFLD to lifestyle interventions.METHODS The Exercise and Diet Adherence Scale(EDAS)was designed based on com-pilation using the Delphi method,and its reliability was subsequently evaluated.Demographic and laboratory indicators were measured,and patients completed the EDAS questionnaire at baseline and after 6 months.The efficacy of the EDAS was evaluated in the initial cohort.Subsequently,the efficacy of the EDAS was internally verified in a validation cohort.RESULTS The EDAS consisted of 33 items in six dimensions,with a total of 165 points.Total EDAS score correlated significantly with daily number of exercise and daily reduction in calorie intake(P<0.05 each),but not with overall weight loss.A total score of 116 was excellent in predicting adherence to daily reduction in calorie intake(>500 kacl/d),(sensitivity/specificity was 100.0%/75.8%),while patients score below 97 could nearly rule out the possibility of daily exercise(sensitivity/specificity was 89.5%/44.4%).Total EDAS scores≥116,97-115,and<97 points were indicative of good,average,and poor adherence,respectively,to diet and exercise recommendations.CONCLUSION The EDAS can reliably assess the adherence of patients with NAFLD to lifestyle interventions and have clinical application in this population. 展开更多
关键词 Fatty liver Lifestyle intervention Behavioral change Patient adherence COMPLIANCE
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How do neurons age?A focused review on the aging of the microtubular cytoskeleton 被引量:1
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作者 Brad Richardson Thomas Goedert +2 位作者 Shmma Quraishe Katrin Deinhardt Amritpal Mudher 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第9期1899-1907,共9页
Aging is the leading risk factor for Alzheimer’s disease and other neurodegenerative diseases. We now understand that a breakdown in the neuronal cytoskeleton, mainly underpinned by protein modifications leading to t... Aging is the leading risk factor for Alzheimer’s disease and other neurodegenerative diseases. We now understand that a breakdown in the neuronal cytoskeleton, mainly underpinned by protein modifications leading to the destabilization of microtubules, is central to the pathogenesis of Alzheimer’s disease. This is accompanied by morphological defects across the somatodendritic compartment, axon, and synapse. However, knowledge of what occurs to the microtubule cytoskeleton and morphology of the neuron during physiological aging is comparatively poor. Several recent studies have suggested that there is an age-related increase in the phosphorylation of the key microtubule stabilizing protein tau, a modification, which is known to destabilize the cytoskeleton in Alzheimer’s disease. This indicates that the cytoskeleton and potentially other neuronal structures reliant on the cytoskeleton become functionally compromised during normal physiological aging. The current literature shows age-related reductions in synaptic spine density and shifts in synaptic spine conformation which might explain age-related synaptic functional deficits. However, knowledge of what occurs to the microtubular and actin cytoskeleton, with increasing age is extremely limited. When considering the somatodendritic compartment, a regression in dendrites and loss of dendritic length and volume is reported whilst a reduction in soma volume/size is often seen. However, research into cytoskeletal change is limited to a handful of studies demonstrating reductions in and mislocalizations of microtubule-associated proteins with just one study directly exploring the integrity of the microtubules. In the axon, an increase in axonal diameter and age-related appearance of swellings is reported but like the dendrites, just one study investigates the microtubules directly with others reporting loss or mislocalization of microtubule-associated proteins. Though these are the general trends reported, there are clear disparities between model organisms and brain regions that are worthy of further investigation. Additionally, longitudinal studies of neuronal/cytoskeletal aging should also investigate whether these age-related changes contribute not just to vulnerability to disease but also to the decline in nervous system function and behavioral output that all organisms experience. This will highlight the utility, if any, of cytoskeletal fortification for the promotion of healthy neuronal aging and potential protection against age-related neurodegenerative disease. This review seeks to summarize what is currently known about the physiological aging of the neuron and microtubular cytoskeleton in the hope of uncovering mechanisms underpinning age-related risk to disease. 展开更多
关键词 age-related changes AGING CYTOSKELETON MICROTUBULES neuronal morphology
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MXene multi-functionalization of polyrotaxane based PCMs and the applications in electronic devices thermal management 被引量:1
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作者 Guangzhong Yin Alba Marta Lopez +5 位作者 Ignacio Collado Antonio Vazquez-Lopez Xiang Ao Jose Hobson Silvia G.Prolongo Deyi Wang 《Nano Materials Science》 EI CAS CSCD 2024年第5期495-503,共9页
The aim of this work was to improve the thermal conductivity and electromagnetic shielding of the leakage proof phase change materials(PCMs),in which a polyrotaxane(PLR)was used as a support material to encapsulate PE... The aim of this work was to improve the thermal conductivity and electromagnetic shielding of the leakage proof phase change materials(PCMs),in which a polyrotaxane(PLR)was used as a support material to encapsulate PEG 1k or PEG 6k and MXene as multi-functional filler.The PCMs can be processed conveniently by a hot press and the PEG 1k containing samples showed excellent flexibility.We conducted a systematic evaluation of the phase transition behavior of the material,thermal conductivity and electromagnetic shielding performance tests.Notably,the PCMs achieved a high enthalpy values(123.9–159.6 J/g).The PCMs exhibited an increase of 44.3%,and 137.5%in thermal conductivity values with higher MXene content(5 wt%)for PLR-PEG6k and PLR-PEG1k,respectively,and show high shape stability and no leakage during and after phase transition.The introduction of MXene can significantly improve the electromagnetic shielding performance of PCM composites.Typically,higher conductive samples(samples which contain high MXene contents)offer a higher EMI SE shielding,reaching a maximum of 4.67 dB at 5.6 GHz for PLR-1K-MX5.These improvements solve the main problems of organic PEG based PCMs,thus making PLR-PEG-MXene based PCMs good candidates for thermoregulators of both solid-state disks and smart phone.It is worth pointing out that the sample PLR-1k-MX5 can decrease 4.3C of the reference temperature during cellphone running.Moreover,the temperature of the protecting sheet in the simulated solid state disk with PCM was significantly lower(showing a decreasing of 7.9℃)compared with the blank sample. 展开更多
关键词 Phase change materials thermal regulation MXene POLYROTAXANE NANOCOMPOSITES
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Development and characterization of the PolyU-1 lunar regolith simulant based on Chang’e-5 returned samples 被引量:1
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作者 Yuan Zou Huanyu Wu +3 位作者 Shupeng Chai Wei Yang Renhao Ruan Qi Zhao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第9期1317-1326,共10页
Leading national space exploration agencies and private enterprises are actively engaged in lunar exploration initiatives to accomplish manned lunar landings and establish permanent lunar bases in the forthcoming year... Leading national space exploration agencies and private enterprises are actively engaged in lunar exploration initiatives to accomplish manned lunar landings and establish permanent lunar bases in the forthcoming years.With limited access to lunar surface materials on Earth,lunar regolith simulants are crucial for lunar exploration research.The Chang’e-5(CE-5)samples have been characterized by state-of-the-art laboratory equipment,providing a unique opportunity to develop a high-quality lunar regolith simulant.We have prepared a high-fidelity PolyU-1 simulant by pulverizing,desiccating,sieving,and blending natural mineral materials on Earth based on key physical,mineral,and chemical characteristics of CE-5 samples.The results showed that the simulant has a high degree of consistency with the CE-5 samples in terms of the particle morphology,mineral and chemical composition.Direct shear tests were conducted on the simulant,and the measured internal friction angle and cohesion values can serve as references for determining the mechanical properties of CE-5 lunar regolith.The PolyU-1 simulant can contribute to experimental studies involving lunar regolith,including the assessment of interaction between rovers and lunar regolith,as well as the development of in-situ resource utilization(ISRU)technologies. 展开更多
关键词 Lunar regolith Simulant Lunar soil mechanics Chang’e-5 ISRU Lunar exploration
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Self‑Assembly of Binderless MXene Aerogel for Multiple‑Scenario and Responsive Phase Change Composites with Ultrahigh Thermal Energy Storage Density and Exceptional Electromagnetic Interference Shielding 被引量:1
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作者 Chuanbiao Zhu Yurong Hao +8 位作者 Hao Wu Mengni Chen Bingqing Quan Shuang Liu Xinpeng Hu Shilong Liu Qinghong Ji Xiang Lu Jinping Qu 《Nano-Micro Letters》 SCIE EI CSCD 2024年第3期367-382,共16页
The severe dependence of traditional phase change materials(PCMs)on the temperature-response and lattice deficiencies in versatility cannot satisfy demand for using such materials in complex application scenarios.Here... The severe dependence of traditional phase change materials(PCMs)on the temperature-response and lattice deficiencies in versatility cannot satisfy demand for using such materials in complex application scenarios.Here,we introduced metal ions to induce the self-assembly of MXene nanosheets and achieve their ordered arrangement by combining suction filtration and rapid freezing.Subsequently,a series of MXene/K^(+)/paraffin wax(PW)phase change composites(PCCs)were obtained via vacuum impregnation in molten PW.The prepared MXene-based PCCs showed versatile applications from macroscale technologies,successfully transforming solar,electric,and magnetic energy into thermal energy stored as latent heat in the PCCs.Moreover,due to the absence of binder in the MXene-based aerogel,MK3@PW exhibits a prime solar-thermal conversion efficiency(98.4%).Notably,MK3@PW can further convert the collected heat energy into electric energy through thermoelectric equipment and realize favorable solar-thermal-electric conversion(producing 206 mV of voltage with light radiation intensity of 200 mw cm^(−2)).An excellent Joule heat performance(reaching 105℃with an input voltage of 2.5 V)and responsive magnetic-thermal conversion behavior(a charging time of 11.8 s can achieve a thermal insulation effect of 285 s)for contactless thermotherapy were also demonstrated by the MK3@PW.Specifically,as a result of the ordered arrangement of MXene nanosheet self-assembly induced by potassium ions,MK3@PW PCC exhibits a higher electromagnetic shielding efficiency value(57.7 dB)than pure MXene aerogel/PW PCC(29.8 dB)with the same MXene mass.This work presents an opportunity for the multi-scene response and practical application of PCMs that satisfy demand of next-generation multifunctional PCCs. 展开更多
关键词 Self-assembly Multiple-scenario Phase change composites thermal energy storage Electromagnetic interference shielding
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Indian monsoon drove the dispersal of the thoracica group of Scytodes spitting spiders 被引量:1
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作者 Yu-Fa Luo Shu-Qiang Li 《Zoological Research》 SCIE CSCD 2024年第1期152-159,共8页
We examined the global biogeography of the Scytodes thoracica group of spitting spiders based on 23 years of sampling at the species level(61 species in the thoracica group and 84 species of Scytodes)using DNA data fr... We examined the global biogeography of the Scytodes thoracica group of spitting spiders based on 23 years of sampling at the species level(61 species in the thoracica group and 84 species of Scytodes)using DNA data from six loci.Our results indicated that the thoracica group initially dispersed from Southeast Asia to East Africa between 46.5 and 33.0 million years ago,and dispersal events intensified between Southeast/South Asia and East/South Africa from the early to late Miocene.The timing of these events indicates that Asian-African faunal exchange of the thoracica group was driven by the Indian monsoon,and the pattern of dispersal suggests that colonialization took root when the Indian monsoon shifted from a North-South direction to an East-West direction from the middle Eocene. 展开更多
关键词 Geological event Climate change Ballooning organism Faunal exchange Species distribution
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