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Dynamic Changes of Vegetation and Its Influences in Forest-grassland Ecotone of Ili Region of Xinjiang from the Concept of Ecological Environment
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作者 Liping ZHANG Haiyan MA +2 位作者 Aihong FU Asiya Manlike Ainiwan Aimaier 《Asian Agricultural Research》 2025年第4期10-13,共4页
[Objectives] To analyze the dynamic changes of maximum vegetation coverage in Ili River Basin from 2006 to 2020,and to explore the vegetation change and its influencing factors in the forest-grassland ecotone of Ili r... [Objectives] To analyze the dynamic changes of maximum vegetation coverage in Ili River Basin from 2006 to 2020,and to explore the vegetation change and its influencing factors in the forest-grassland ecotone of Ili region.[Methods] The pixel dichotomy model was used to process the MODIS data and analyze the change of vegetation coverage in the Ili River Basin from 2006 to 2020.[Results] (i)The vegetation coverage in the Ili River Basin increases gradually from west to east,and fluctuates greatly between years.(ii)By monitoring the change rate of the maximum vegetation coverage,it is found that the vegetation coverage of the basin has experienced a process of first decline and then recovery in the past 15 years.(iii)In spatial distribution,vegetation coverage has improved in some regions,while it has deteriorated in others,which may be related to regional climate change and human activities.[Conclusions] The vegetation coverage in the Ili River Basin showed significant spatial and temporal differences during the study period,and its changes were affected by both natural and human factors. 展开更多
关键词 Ecological environment Ili region of Xinjiang Forest-grassland ecotone Vegetation dynamic changes
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Dynamic changes of gravity field before the Luding Ms6.8 earthquake and its crustal material migration characteristics
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作者 Qingqing Tan Chongyang Shen +5 位作者 Jiapei Wang Xiong Yang Wen Jin Minghui Zhang Hongbo Tan Guangliang Yang 《Geodesy and Geodynamics》 2025年第2期214-222,共9页
On September 5, 2022, an earthquake of magnitude M_(S)6.8 occurred in Luding County, Sichuan Province.This earthquake occurred at the key part of the southeast-clockwise extrusion of material on the eastern margin of ... On September 5, 2022, an earthquake of magnitude M_(S)6.8 occurred in Luding County, Sichuan Province.This earthquake occurred at the key part of the southeast-clockwise extrusion of material on the eastern margin of the Qinghai Plateau, the Y-shaped confluence of the Xianshuihe, Longmenshan and Anninghe fault zones. In this study, the three-dimensional dynamic crustal density changes in the earthquake area are obtained by the typical gravity change data from 2019 to 2022 before the earthquake and gravity inversion by growing bodies. The results indicate that gravity changes presented an obvious fourquadrant and gradient belt distribution in the Luding area before the earthquake. The threedimensional density horizontal slices show that small density changes occurred at the epicenter in the mid-to-upper crust between 2019.9-2020.9 and 2019.9-2021.9. At the same time, the surrounding areas exhibited a positive and negative quadrant distribution. These observations indicate that the source region was likely in a stable locked state, with locking-in shear forces oriented in the NW and NE directions. From 2021.9 to 2022.8, the epicentral region showed negative density changes, indicating that the source region was in the expansion stage, approaching a near-seismic state. The three-dimensional density vertical slices reveal a southeastward migration of positive and negative densities near the epicenter and on the western of the Xianshuihe Fault Zone, indicating that the material is flowing out to the southeast. The observed local negative density changes at the epicenter along the Longmenshan Fault Zone are likely associated with the NE-oriented extensional stress shown by the seismic source mechanism. The above results can provide a basis for interpreting pre-earthquake gravity and density changes,thereby contributing to the advancement of earthquake precursor theory. 展开更多
关键词 Luding earthquake Gravity changes Three-dimensional density changes Gravity inversion
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Climate change-based dynamic simulation of land use and carbon storage in urban agglomerations of the Yangtze River Economic Belt
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作者 PAN Sipei LIANG Jiale +3 位作者 GUO Jie CHEN Wanxu OU Minghao DE VRIES Walter T 《Journal of Geographical Sciences》 2025年第7期1432-1458,共27页
Low-carbon urban development in China can pave the way to achieve the dualcarbon goal.Exploring how land use changes(LUCs)impact carbon storage(CS)under multi-climate scenarios in different urban agglomerations helps ... Low-carbon urban development in China can pave the way to achieve the dualcarbon goal.Exploring how land use changes(LUCs)impact carbon storage(CS)under multi-climate scenarios in different urban agglomerations helps to formulate differential scientific carbon mitigation policies.In this regard,this study constructs an integrated model of SD-PLUS-InVEST to simulate LUCs and CS changes under multi-climate change-based scenarios(SSP126,SSP245,SSP585)for three major urban agglomerations(3UAs)in the Yangtze River Economic Belt.Results demonstrate that land use demand in the 3UAs changes considerably in each scenario.Construction land in the 3UAs remains the most important growth category for the coming decade,but its increase varies in different scenarios.CS in the Yangtze River Delta Urban Agglomeration(YRDUA)and Mid-Yangtze River Urban Agglomeration(MYRUA)shows a similar downward trend under different scenarios,with scenario SSP245 decreasing the most,to 184,713.526 Tg and 384,459.729 Tg,respectively.CS in the Cheng-Yu(Chengdu-Chongqing)Urban Agglomeration(CYUA)exhibits the opposite upward trend,with scenario SSP126 increasing the most to 153,007.973 Tg.The major cause of CS loss remains the conversion of forest land to construction land in the YRDUA and MYRUA under different scenarios.However,in the CYUA,the conversion of forest land to cultivated land is the major driver of CS loss under scenario SSP126.In contrast,the conversion of cultivated land to construction land dominantly drives CS loss under scenarios SSP245 and SSP585.The conversion of water body to other land use types is the major cause of CS gain in the YRDUA and MYRUA under different scenarios.At the same time,in the CYUA,the driver is the conversion of cultivated land to forest land.These findings demonstrate the significance of the low-carbon development in urban agglomerations at different development stages at home and abroad. 展开更多
关键词 carbon storage land use change climate change SD-PLUS-InVEST model urban agglomerations China
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Coulomb stressing rate changes and seismicity dynamics associated with slow slip events in south-central Alaska
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作者 ShanShan Li XingLei Li Bing Xu 《Earth and Planetary Physics》 2025年第2期289-308,共20页
Two long-term slow slip events(SSEs) in Lower Cook Inlet, Alaska, were identified by Li SS et al.(2016). The earlier SSE lasted at least 9 years with M_(w) ~7.8 and had an average slip rate of ~82 mm/year. The latter ... Two long-term slow slip events(SSEs) in Lower Cook Inlet, Alaska, were identified by Li SS et al.(2016). The earlier SSE lasted at least 9 years with M_(w) ~7.8 and had an average slip rate of ~82 mm/year. The latter SSE, occurring in a similar area, lasted approximately 2 years with M_(w) ~7.2 and an average slip rate of ~91 mm/year. To test whether these SSEs triggered earthquakes near the slow slip area, we calculated the Coulomb stressing rate changes on receiver faults by using two fault geometry definitions: nodal planes of focal mechanism solutions of past earthquakes, and optimally oriented fault planes. Regions in the shallow slab(30–60 km) that experienced a significant increase in the Coulomb stressing rate due to slip by the SSEs showed an increase in seismicity rates during SSE periods. No correlation was found in the volumes that underwent a significant increase in the Coulomb stressing rate during the SSE within the crust and the intermediate slab. We modeled variations in seismicity rates by using a combination of the Coulomb stress transfer model and the framework of rate-and-state friction. Our model indicated that the SSEs increased the Coulomb stress changes on adjacent faults,thereby increasing the seismicity rates even though the ratio of the SSE stressing rate to the background stressing rate was small. Each long-term SSE in Alaska brought the megathrust updip of the SSE areas closer to failure by up to 0.1–0.15 MPa. The volumes of significant Coulomb stress changes caused by the Upper and Lower Cook Inlet SSEs did not overlap. 展开更多
关键词 slow slip events Coulomb stressing rate change seismicity rate change receiver fault rate–state stress transfer model seismogenic zone megathrust failure
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Arctic Ocean Dynamical Downscaling Data for Understanding Past and Future Climate Change
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作者 Qi SHU Qiang WANG +6 位作者 Yan HE Zhenya SONG Gui GAO Hailong LIU Shizhu WANG Rongrong PAN Fangli QIAO 《Advances in Atmospheric Sciences》 2025年第9期1761-1775,共15页
The Arctic is one of Earth’s regions highly susceptible to climate change.However,in situ long-term observations used for climate research are relatively sparse in the Arctic Ocean,and current climate models exhibit ... The Arctic is one of Earth’s regions highly susceptible to climate change.However,in situ long-term observations used for climate research are relatively sparse in the Arctic Ocean,and current climate models exhibit notable biases in Arctic Ocean simulations.Here,we present an Arctic Ocean dynamical downscaling dataset,obtained from the global ocean-sea ice model FESOM2 with a regionally refined horizonal resolution of 4.5 km in the Arctic region,which is driven by bias-corrected surface forcings derived from a climate model.The dataset includes 115 years(1900-2014)of historical simulations and two 86-year future projection simulations(2015-2100)for the SSP2-4.5 and SSP5-8.5 scenarios.The historical simulations demonstrate substantially reduced biases in temperature,salinity and sea-ice thickness compared to CMIP6 climate models.Common biases in the representation of the Atlantic Water layer found in climate model simulations are also markedly reduced in the dataset.Serving as a crucial long-term data source for climate change assessments and scientific research for the Arctic Ocean,this dataset provides valuable information for the scientific community. 展开更多
关键词 Arctic Ocean climate change CMIP6 FESOM2 FIO-ESM
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Dynamic and polarization-independent high-Q guided resonances in metasurfaces with phase change material
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作者 Guozhong Zhang Mimi Zhou +1 位作者 Hong Xiang Dezhuan Han 《Chinese Physics B》 2025年第8期576-582,共7页
Using periodic refractive index perturbations,the Brillouin zone is folded,transforming the guided modes in a metasurface into guided resonances with arbitrarily high quality-factors.The incorporation of phase change ... Using periodic refractive index perturbations,the Brillouin zone is folded,transforming the guided modes in a metasurface into guided resonances with arbitrarily high quality-factors.The incorporation of phase change materials within the metasurface enables dynamic modulation of the guided modes.The system’s symmetry ensures a polarization-independent response under normal incidence.Furthermore,the metasurface exhibits excellent sensing performance,demonstrating its potential for advanced photonic applications. 展开更多
关键词 Brillouin zone folding phase change material guided resonance sensing
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Recyclable,Flexible and Highly Thermally Conductive Phase Change Composites with Dynamic Networks for Thermal Management
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作者 Jun-Xia Guo Shuang-Yu Cai +6 位作者 Xu Han Ye Sun Chun-Lin Li Kai Zheng Yu-Ze Xu Rui-Guang Li Cheng-Jie Li 《Chinese Journal of Polymer Science》 2025年第4期625-639,共15页
Flexible phase change materials(PCMs)have become increasingly critical to address the demand for thermal management in electronic technologies and energy conversion.However,their application remains challenging becaus... Flexible phase change materials(PCMs)have become increasingly critical to address the demand for thermal management in electronic technologies and energy conversion.However,their application remains challenging because of their rigidity,liquid leakage,and insufficient thermal conductivity.Herein,flexible glutamic acid@natural rubber/paraffin wax(PW)/carbon nanotubes-graphene nanoplatelets(GNR/PW/CGNP)phase change composites with high thermal conductivity,excellent shape stability,and recyclability were reported.Zn^(2+)-based dynamic crosslinking was constructed through the reaction of zinc acetate and carboxyl groups on glutamic acid@natural rubber(GNR),which was used as a flexible matrix to physically blend with paraffin wax/carbon nanotubes/graphene nanoplatelets(PW/CGNP)to achieve uniform dispersion of PW/CGNP,continuous thermal conductivity networks,and good encapsulation of PW.The GNR/PW/CGNP composites showed excellent mechanical strength,flexibility,and recycling ability,and effective encapsulation prevented the outflow of melted PW during the phase transition.Also,the phase change enthalpy could attain 111.1 J/g with a higher thermal conductivity of 1.055 W/m K,428%higher than that of pure PW owing to the formation of efficient thermal conductive pathways,which exhibited outstanding thermal management performance and superior temperature control behavior in electronic devices.The developed flexible composite PCMs may open new possibilities for next-generation flexible thermal management electronics. 展开更多
关键词 Phase change composites Mechanical flexibility Shape stability Recycling ability Thermal management
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Understanding the C-C coupling mechanism in electrochemical CO reduction at low CO coverage:Dynamic change in site preference matters
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作者 Zhe Chen Tao Wang 《Chinese Journal of Catalysis》 2025年第2期193-202,共10页
A thoroughly mechanistic understanding of the electrochemical CO reduction reaction(eCORR)at the interface is significant for guiding the design of high-performance electrocatalysts.However,unintentionally ignored fac... A thoroughly mechanistic understanding of the electrochemical CO reduction reaction(eCORR)at the interface is significant for guiding the design of high-performance electrocatalysts.However,unintentionally ignored factors or unreasonable settings during mechanism simulations will result in false positive results between theory and experiment.Herein,we computationally identified the dynamic site preference change of CO adsorption with potentials on Cu(100),which was a previously unnoticed factor but significant to potential-dependent mechanistic studies.Combined with the different lateral interactions among adsorbates,we proposed a new C–C coupling mechanism on Cu(100),better explaining the product distribution at different potentials in experimental eCORR.At low potentials(from–0.4 to–0.6 V_(RHE)),the CO forms dominant adsorption on the bridge site,which couples with another attractively aggregated CO to form a C–C bond.At medium potentials(from–0.6 to–0.8 VRHE),the hollow-bound CO becomes dominant but tends to isolate with another adsorbate due to the repulsion,thereby blocking the coupling process.At high potentials(above–0.8 VRHE),the CHO intermediate is produced from the electroreduction of hollow-CO and favors the attraction with another bridge-CO to trigger C–C coupling,making CHO the major common intermediate for C–C bond formation and methane production.We anticipate that our computationally identified dynamic change in site preference of adsorbates with potentials will bring new opportunities for a better understanding of the potential-dependent electrochemical processes. 展开更多
关键词 Electrochemical CO reduction reaction Lowco coverage dynamic site-preference Potential-dependent C-C coupling Constant-potential density functional theory
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Long-term leaf nitrogen and phosphorus dynamics and drivers in China's forests under global change
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作者 Chenxi Li Honglin He +6 位作者 Xinyu Zhang Xiaoli Ren Liang Shi Li Zhang Qian Xu Mengyu Zhang Yonghong Zhang 《Forest Ecosystems》 2025年第4期668-676,共9页
The leaf nitrogen(N)to phosphorus(P)ratio(N:P)is a critical indicator of nutrient dynamics and ecosystem function.Investigating temporal variations in leaf N:P can provide valuable insights into how plants adapt to en... The leaf nitrogen(N)to phosphorus(P)ratio(N:P)is a critical indicator of nutrient dynamics and ecosystem function.Investigating temporal variations in leaf N:P can provide valuable insights into how plants adapt to environmental changes and nutrient availability.However,limited research has been conducted on long-term temporal leaf N:P variation over a range of temperature zones.Using long-term monitoring data from the Chinese Ecosystem Research Network(CERN),we investigated temporal changes in leaf N and P stoichiometry for 50 dominant tree species from 10 typical forest sites across temperate and subtropical regions,and identified the underlying mechanisms driving these changes.For both regions combined,leaf P concentration of the 50 dominant tree species decreased(20.6%),whereas leaf N:P increased(52.0%)from 2005 to 2020.Leaf P decreased and leaf N:P increased in 67% and 69% of the tree species,respectively.The leaf N:P increase was primarily driven by the tree species in eastern subtropical forests,where global change factors and soil nutrients explained 68% of leaf N:P variation.The P limitation exhibited by tree species in eastern subtropical forest ecosystems intensified over time,and elevated temperature and CO_(2) levels,coupled with decreased soil available P concentrations,appear to be the main factors driving long-term leaf N:P increases in these forests.Investigating long-term variations in soil nutrients together with global change factors will improve our understanding of the nutrient status of forest ecosystems in the context of global change and will support effective forest ecosystem management. 展开更多
关键词 Leaf nitrogen(N) Leaf phosphorus(P) Leaf N:P Temporal trends Global change factors Soil available phosphorus
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Dynamic response of the ground beneath a high-speed railway based on typical upper Shanghai clays involving water table change
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作者 Jing HU Chengming YE +3 位作者 Juntao JIANG Shujing WU David THOMPSON Xuecheng BIAN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 2025年第8期787-800,共14页
A rising water table increases soil water content,reduces soil strength,and amplifies vibrations under identical train loads,thereby posing greater risks to train operations.To investigate this phenomenon,we used a 2.... A rising water table increases soil water content,reduces soil strength,and amplifies vibrations under identical train loads,thereby posing greater risks to train operations.To investigate this phenomenon,we used a 2.5D finite element(FE)model of a coupled vehicle–embankment–ground system based on Biot’s theory.The ground properties were derived from a typical soil profile of the Yangtze River basin,using geological data from Shanghai,China.The findings indicate that a rise in the water table leads to increased dynamic displacements of both the track and the ground.This amplification effect extends beyond the depth of the water table,impacting the entire embankment–foundation cross-section,and intensifies with higher train speeds.However,the water table rise has a limited impact on the critical speed of trains and dominant frequency contents.The dynamic response of the embankment is more significantly affected by water table rises within the subgrade than by those within the ground.When the water table rises into the subgrade,significant excess pore pressure is generated inside the embankment,causing a substantial drop in effective stress.As a result,the stress path of the soil elements in the subgrade approaches the Mohr-Coulomb failure line,increasing the likelihood of soil failure. 展开更多
关键词 dynamic response Excess pore pressures Water table rise High-speed train 2.5D finite element(FE)model
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Efficacy of dynamic interpersonal therapy in improving mentalising in patients with major depressive disorder and the mediating effect of mentalising on changes in depressive symptoms
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作者 Wenhui Jiang Jiayu Yao +4 位作者 Yuan Wang Shanshan Su Ziwei Zheng Yang Yang Jianyin Qiu 《General Psychiatry》 2025年第1期16-25,共10页
Background Dynamic interpersonal therapy(DIT)is a short-term psychodynamic psychotherapy that has been shown to effectively reduce depressive symptoms in patients with major depressive disorder(MDD).In DIT,the depress... Background Dynamic interpersonal therapy(DIT)is a short-term psychodynamic psychotherapy that has been shown to effectively reduce depressive symptoms in patients with major depressive disorder(MDD).In DIT,the depressive symptoms are formulated as responses to impaired mentalisation.DIT aims to alleviate depressive symptoms by improving mentalising.Aims This study aimed to examine the effect of DIT on improving mentalising and the mediating effect of mentalising in changes in depressive symptoms.Methods Outpatients received either DIT combined with antidepressant medication treatment(DIT group)or antidepressant medication treatment alone(ADM group)for 16 weeks.The Hamilton Depression Rating Scale(HAMD),Patient Health Questionnaire(PHQ)and Reflective Functioning Questionnaire(RFQ)were used.The intention-to-treat principle,mixed linear models,multiple imputation,Pearson's correlation analysis and mediation analysis were conducted.The per-protocol principle was used as sensitivity analysis.Results The DIT group had significantly lower HAMD(least-squares(LS)mean difference=-3.756,p<0.001),PHQ(LS mean difference=-4.188,p<0.001),uncertainty about mental states in the RFQ(RFQ-U,LS mean difference=-2.116,p<0.001)and higher certainty about mental states in the RFQ(RFQ-C,LS mean difference=2.214,p=0.028)scores than the ADM group at post-treatment.The change in RFQ-C was marginally significantly correlated with the change in HAMD(r=-0.218,poretao=0.090),The change in RFQ-U was significantly correlated with the change in HAMD(r=-0.269,poroco-0.024)and the change in PHQ(r=-0.43,Peoretceo l<e0.001).When using RFQ-U as the mediating variable and PHQ as the dependent variable,a significant mediating effect was found(p=0.043,95% confidence interval 0.024 to 1.453).Conclusions The DIT group yielded better outcomes compared with the ADM group in reducing depressive symptoms and improving mentalising.Improvements in mentalising were associated with reductions in depressive symptoms.These findings support that mentalising may contribute to the therapeutic effects of DIT in MDD. 展开更多
关键词 alleviate depressive symptoms Mentalising dynamic interpersonal therapy dit improving mentalising improving mentalisingaims reduce depressive symptoms psychodynamic psychotherapy depressive symptoms
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Dynamic changes of spontaneous brain activity in patients after LASIK:a resting-state fMRI study
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作者 Hui Zhang Zi-Song Xu +11 位作者 Jin-Yu Hu Zhen-Zhe Liu Lei Zhong Liang-Qi He Cheng Chen Xiao-Yu Wang Hong Wei Yan-Mei Zeng Qian Ling Xu Chen Yi-Xin Wang Yi Shao 《International Journal of Ophthalmology(English edition)》 2025年第3期487-495,共9页
AIM:To investigate changes in local brain activity after laser assisted in situ keratomileusis(LASIK)in myopia patients,and further explore whether post-LASIK(POL)patients and healthy controls(HCs)can be distinguished... AIM:To investigate changes in local brain activity after laser assisted in situ keratomileusis(LASIK)in myopia patients,and further explore whether post-LASIK(POL)patients and healthy controls(HCs)can be distinguished by differences in dynamic amplitude of low-frequency fluctuations(dALFF)in specific brain regions.METHODS:The resting-state functional magnetic resonance imaging(rs-fMRI)data were collected from 15 myopic patients who underwent LASIK and 15 matched healthy controls.This method was selected to calculate the corresponding dALFF values of each participant,to compare dALFF between the groups and to determine whether dALFF distinguishes reliably between myopic patients after LASIK and HCs using the linear support vector machine(SVM)permutation test(5000 repetitions).RESULTS:dALFF was lower in POL than in HCs at the right precentral gyrus and right insula.Classification accuracy of the SVM was 89.1%(P<0.001).CONCLUSION:The activity of spontaneous neurons in the right precentral gyrus and right insula of myopic patients change significantly after LASIK.SVM can correctly classify POL patients and HCs based on dALFF differences. 展开更多
关键词 laser assisted in situ keratomileusis resting-state functional magnetic resonance imaging dynamic brain activity amplitude of low-frequency fluctuations support vector machine
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Greenhouse gas emission dynamics and climate change mitigation efforts toward sustainability in the Middle East and North Africa(MENA)region
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作者 Syed Masiur RAHMAN Asif RAIHAN +1 位作者 Md Shafiul ALAM Shakhawat CHOWDHURY 《Regional Sustainability》 2025年第4期61-77,共17页
Greenhouse gas(GHG)emssions from fossil fuel consumption are driving global climate change.This study applied the fully modified ordinary least squares(FMOLS)model and pairwise panel Granger causality test to explore ... Greenhouse gas(GHG)emssions from fossil fuel consumption are driving global climate change.This study applied the fully modified ordinary least squares(FMOLS)model and pairwise panel Granger causality test to explore the relationships of GHG emissions with gross domestic product(GDP),population,urbanization,natural resource rents,foreign direct investment(FDI),and renewable energy consumption in 12 Middle East and North Africa(MENA)countries(Algeria,Bahrain,Comoros,Djibouti,Egypt,Qatar,Somalia,Saudi Arabia,Syria,the United Arab Emirates,Tunisia,and Yemen)from 1990 to 2023.Due to the limited data on renewable energy after 2020,the coverage of renewable energy consumption is from 1990 to 2021.Findings showed that Saudi Arabia,Egypt,Algeria,the United Arab Emirates,and Qatar are the top 5 GHG emitters in the MENA region,with the GHG emissions of the energy sector rising fastest among all sectors.Results also indicated that a 1.00%increase in GDP,population,urbanization,natural resource rents,and FDI raises GHG emissions by 0.48%,0.61%,0.86%,0.29%,and 0.11%,respectively.Conversely,a 1.00%increase in renewable energy consumption reduces GHG emissions by 0.13%.Effective policies promoting renewable energy investment and the adoption of renewable energy could significantly reduce electricity costs and GHG emissions,contributing to achieving climate goals,such as net-zero emissions and environmental sustainability.Additionally,the increase of renewable energy consumption and technology development would improve energy efficiency,create jobs,and stimulate economic growth in the MENA region.This study recommends tailored policy instruments to support the transition to low-emission technologies and strategies. 展开更多
关键词 Climate change Greenhouse gas(GHG)emissions Renewable energy consumption Fully modified ordinary least squares(FMOLS)model Middle East and North Africa(MENA)region
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血清IL-6联合MoCA评分、CHANGE风险评分对急性脑卒中后认知障碍的多维度预测模型研究
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作者 郭莞莹 舒可 +2 位作者 王若怡 亚金蓉 杨鹤云 《现代生物医学进展》 2025年第18期2981-2987,共7页
目的:探讨血清白细胞介素-6(interleukin-6,IL-6)联合蒙特利尔认知评估量表(Montreal Cognitive Assessment,Mo CA)评分、CHANGE风险评分在急性脑卒中后认知障碍(post-stroke cognitive impairment,PSCI)的预测价值,为高风险患者早期识... 目的:探讨血清白细胞介素-6(interleukin-6,IL-6)联合蒙特利尔认知评估量表(Montreal Cognitive Assessment,Mo CA)评分、CHANGE风险评分在急性脑卒中后认知障碍(post-stroke cognitive impairment,PSCI)的预测价值,为高风险患者早期识别及干预提供依据。方法:回顾性分析2022年10月至2024年9月我院收治的200例急性脑卒中患者的一般资料,根据急性脑卒中后3个月是否发生PSCI分为PSCI组(49例)和非PSCI组(151例)。对比两组的一般资料,采用多因素Logistic回归分析PSCI影响因素,并使用受试者工作特征(receiver operating characteristic,ROC)曲线评估血清IL-6、MoCA评分及CHANGE风险评分对PSCI发生的预测效能。结果:两组年龄、受教育程度比较差异有统计学意义(P<0.05)。PSCI组血清IL-6水平及CHANGE风险评分高于非PSCI组,MoCA评分低于非PSCI组(P<0.05)。多因素Logistic回归显示IL-6水平升高(OR=1.851,P=0.001)、CHANGE风险评分升高(OR=1.076,P=0.016)是PSCI发生的独立危险因素,MoCA评分升高(OR=0.806,P=0.001)是保护因素(P<0.05)。IL-6水平、MoCA评分及CHANGE风险评分均对预测PSCI发生有较高的效能,三者单独预测PSCI发生的曲线下面积(area under the curve,AUC)分别为0.783、0.825、0.857,三者联合检测AUC为0.912,显著高于各指标单独检测。结论:血清IL-6升高、MoCA评分降低及CHANGE风险评分升高是PSCI的危险因素,三者联合检测模型对PSCI发生的预测效能最高,可为临床早期干预提供科学依据。 展开更多
关键词 急性脑卒中 卒中后认知障碍 白细胞介素-6 蒙特利尔认知评估量表 change风险评分
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Dynamic Changes of Nutrients in Different Growth Stages of Trichosanthes kirilowii in Shishou City
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作者 Fengyun XIANG Xiaomin PEI +5 位作者 Tianya LIU Qinyun GAO Aomingyang LI Shiping GUO Qifei FU Jifu LI 《Meteorological and Environmental Research》 2024年第5期63-69,共7页
To explore the relationship between soil nutrients,plant nutrients,and the growth and development of Trichosanthes kirilowii,the soil pH,organic matter,available nitrogen,available phosphorus,available potassium conte... To explore the relationship between soil nutrients,plant nutrients,and the growth and development of Trichosanthes kirilowii,the soil pH,organic matter,available nitrogen,available phosphorus,available potassium content,and leaf total nitrogen,total phosphorus,total potassium,and SPAD in different growth stages of T.kirilowii in the main production area of Shishou City were measured and analyzed.The changes in soil nutrient content and leaf nutrient content at different growth stages of T.kirilowii were compared,and correlation analysis was conducted.The results showed that the average soil pH,organic matter content,alkaline nitrogen content,available phosphorus content,and available potassium content during the entire growth period of T.kirilowii were 7.03,14.01 g/kg,98.79 mg/kg,14.84 mg/kg,and 135.20 mg/kg,respectively;the average total nitrogen content,total phosphorus content,total potassium content,and SPAD of the leaves were 0.55%,0.23%,1.78%,and 77.66,respectively.The nutrient dynamics of T.kirilowii at different growth stages exhibited certain regularity,with most nutrients reaching their maximum values during the flowering and fruiting stages,and then showing a decreasing or stabilizing trend.There was a varying degree of correlation between the nutrient content of leaves and soil,among which the nitrogen,phosphorus,and potassium contents of leaves were significantly or extremely significantly correlated with soil organic matter and alkaline nitrogen content.It can be seen that the nutrient abundance or deficiency level of soil in T.kirilowii field significantly affected the nutrient content of the leaves at different growth stages,thereby restricting its growth and development status. 展开更多
关键词 Trichosanthes kirilowii Soil nutrients Leaf nutrients dynamic changes Correlation analysis
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Analysis of Imaging Characteristics and Dynamic Changes of 3 Cases of Severe Novel Coronavirus Pneumonia in Qinghai Province
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作者 Yingfang Yu Ruiyun Zhao +3 位作者 Changde Li Fuqiang Ma Lingyun Guo Yang Li 《Journal of Clinical and Nursing Research》 2024年第3期120-126,共7页
Objective:To analyze the characteristics,dynamic changes,and outcomes of the first imaging manifestations of 3 patients with severe COVID-19 in our hospital.Methods:Computed tomography(CT)findings of 3 patients with s... Objective:To analyze the characteristics,dynamic changes,and outcomes of the first imaging manifestations of 3 patients with severe COVID-19 in our hospital.Methods:Computed tomography(CT)findings of 3 patients with severe COVID-19 who tested positive by the nucleic acid test in our hospital were selected,mainly focusing on the morphology,distribution characteristics,and dynamic changes of the first CT findings.Results:3 patients with severe pneumonia were older,with one aged 80.The first chest CT examination for all 3 patients differed.Imaging showed a leafy distribution of consolidation,primarily affecting the lower lobes of both lungs and extending subpleurally.A grid-like pattern was observed,along with changes in the consolidation and air bronchogram.These changes had slower absorption,especially in patients with underlying diseases.Conclusion:CT manifestations of severe COVID-19 have specific characteristics and the analysis of their characteristics and dynamic changes provide valuable insights for clinical treatment. 展开更多
关键词 COVID-19 IMAGING CT findings dynamic changes
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Dynamic Distribution Changes of Giant Pandas and Human Disturbance in the Habitat of Qionglai Mountains
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作者 Bingnan DONG Jian CAI Xing FAN 《Agricultural Biotechnology》 2024年第6期14-16,21,共4页
The giant panda(Ailuropoda melanoleuca),as a rare and endangered wild animal in China,has attracted wide attention from all walks of life.In this study,the changes of disturbances in the habitat of giant panda populat... The giant panda(Ailuropoda melanoleuca),as a rare and endangered wild animal in China,has attracted wide attention from all walks of life.In this study,the changes of disturbances in the habitat of giant panda population in the Qionglai Mountains of Sichuan Province were studied and analyzed by comparing the data of two giant panda surveys in Qionglai Mountains and combining with the remote sensing(ES)data of related areas.The results showed that the number of general disturbances in the habitat of giant pandas in Qionglai Mountains greatly reduced in 10 years,and the types of disturbances also changed greatly.The logging disturbance which was most distributed in the third survey almost disappeared in the fourth survey,and the grazing disturbance in the habitat became the disturbance type with the highest encounter rate.The density of human activities in the whole mountain system greatly decreased,but the scope was slightly expanded.Baoxing and Lushan were areas with high density of giant panda activities,and the number of various human activities was relatively large.In the two surveys,the avoidance effect of giant pandas on logging,grazing,roads,hunting and other disturbances showed significant differences.The activity density of local small populations of giant pandas in Qionglai Mountains changed. 展开更多
关键词 Qionglai Mountains Giant panda Human disturbance dynamic distribution change
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Quantitative contributions of climate change and human activities to vegetation dynamics in the Zoige Plateau from 2001 to 2020
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作者 GAO Bing LIU Enqin +4 位作者 YANG Yang YANG Man YAO Yang GUAN Lei FENG Yiwen 《Journal of Mountain Science》 SCIE CSCD 2024年第9期3031-3046,共16页
Climate change and human activities such as overgrazing and rapid development of tourism simultaneously affected the vegetation of the Zoige Plateau.However,the spatiotemporal variations of vegetation and the relative... Climate change and human activities such as overgrazing and rapid development of tourism simultaneously affected the vegetation of the Zoige Plateau.However,the spatiotemporal variations of vegetation and the relative contributions of climate change and human activities to these vegetation dynamics remain unclear.Therefore,clarifying how and why the vegetation on the Zoige Plateau changed can provide a scientific basis for the sustainable development of the region.Here,we investigate NDVI trends using the Normalized Difference Vegetation Index(NDVI)as an indicator of vegetation greenness and distinguish the relative effects of climate changes and human activities on vegetation changes by utilizing residual trend analysis and the Geodetector.We find a tendency of vegetation greening from 2001 to 2020,with significant greening accounting for 21.44%of the entire region.However,browning area expanded rapidly after 2011.Warmer temperatures are the primary driver of vegetation changes in the Zoige Plateau.Climatic variations and human activities were responsible for 65.57%and 34.43%of vegetation greening,and 39.14%and 60.86%of vegetation browning,respectively,with browning concentrated along the Yellow,Black and White Rivers.Compared to 2001-2010,the inhibitory effect of human activity and climate fluctuations on vegetation grew dramatically between 2011 and 2020. 展开更多
关键词 Vegetation change Climate change Residual trend analysis Geodetector Human activities Zoige plateau
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Changes of mitochondrial dynamics during the progression of non-alcoholic fatty liver disease: a review 被引量:1
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作者 Man-Na Li Ling Yang +5 位作者 Huan-Tian Cui Jia-Bao Liao Ning Wang Jing Miao Ying Zhang Hai-Di Wang 《Biomedical Engineering Communications》 2024年第1期15-20,共6页
Non-alcoholic fatty liver disease(NAFLD)is a chronic liver disease closely related to metabolic disorders that pose a serious threat to human health.Currently,no specific drugs are available for treating the aetiology... Non-alcoholic fatty liver disease(NAFLD)is a chronic liver disease closely related to metabolic disorders that pose a serious threat to human health.Currently,no specific drugs are available for treating the aetiology of NAFLD in clinical practice.Mitochondria have various biological functions inside the cell.Studies have found that mitochondrial fission and fusion are closely related to NAFLD.Therefore,identifying therapeutic targets for NAFLD through mitochondrial fission and fusion is crucial.Particularly in the field of traditional Chinese medicine,good therapeutic effects have been achieved in the treatment of NAFLD by protecting mitochondrial fusion and fission.Therefore,this article reviews the relationship between mitochondrial dynamics and NAFLD as well as the treatment of NAFLD through the regulation of mitochondrial fission and fusion with traditional Chinese medicine to provide a reference for the clinical application of traditional Chinese medicine in regulating mitochondrial fission and fusion functions to treat NAFLD. 展开更多
关键词 mitochondrial dynamics NAFLD traditional Chinese medicine
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Coupled effects of climate change and human activities on vegetation dynamics in the Southwestern Alpine Canyon Region of China
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作者 LAI Jinlin QI Shi 《Journal of Mountain Science》 SCIE CSCD 2024年第10期3234-3248,共15页
The driving effects of climate change and human activities on vegetation change have always been a focal point of research.However,the coupling mechanisms of these driving factors across different temporal and spatial... The driving effects of climate change and human activities on vegetation change have always been a focal point of research.However,the coupling mechanisms of these driving factors across different temporal and spatial scales remain controversial.The Southwestern Alpine Canyon Region of China(SACR),as an ecologically fragile area,is highly sensitive to the impacts of climate change and human activities.This study constructed a vegetation cover dataset for the SACR based on the Enhanced Vegetation Index(EVI)from 2000 to 2020.Spatial autocorrelation,Theil-Sen trend,and Mann-Kendall tests were used to analyze the spatiotemporal characteristics of vegetation cover changes.The main drivers of spatial heterogeneity in vegetation cover were identified using the optimal parameter geographic detector,and an improved residual analysis model was employed to quantify the relative contributions of climate change and human activities to interannual vegetation cover changes.The main findings are as follows:Spatially,vegetation cover exceeds 60%in most areas,especially in the southern part of the study area.However,the border area between Linzhi and Changdu exhibits lower vegetation cover.Climate factors are the primary drivers of spatial heterogeneity in vegetation cover,with temperature having the most significant influence,as indicated by its q-value,which far exceeds that of other factors.Additionally,the interaction q-value between the two factors significantly increases,showing a relationship of bivariate enhancement and nonlinear enhancement.In terms of temporal changes,vegetation cover shows an overall improving trend from 2000 to 2020,with significant increases observed in 68.93%of the study area.Among these,human activities are the main factors driving vegetation cover change,with a relative contribution rate of 41.31%,while climate change and residual factors contribute 35.66%and 23.53%,respectively.By thoroughly exploring the coupled mechanisms of vegetation change,this study provides important references for the sustainable management and conservation of the vegetation ecosystem in the SACR. 展开更多
关键词 Enhanced vegetation index Climate change Human activities Spatial heterogeneity Coupled mechanisms
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