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Diffusion kurtosis imaging of microstructural changes in brain tissue affected by acute ischemic stroke in different locations 被引量:27
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作者 Liu-Hong Zhu Zhong-Ping Zhang +2 位作者 Fu-Nan Wang Qi-Hua Cheng Gang Guo 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第2期272-279,共8页
The location of an acute ischemic stroke is associated with its prognosis. The widely used Gaussian model-based parameter, apparent diffusion coefficient(ADC), cannot reveal microstructural changes in different locati... The location of an acute ischemic stroke is associated with its prognosis. The widely used Gaussian model-based parameter, apparent diffusion coefficient(ADC), cannot reveal microstructural changes in different locations or the degree of infarction. This prospective observational study was reviewed and approved by the Institutional Review Board of Xiamen Second Hospital, China(approval No. 2014002).Diffusion kurtosis imaging(DKI) was used to detect 199 lesions in 156 patients with acute ischemic stroke(61 males and 95 females), mean age 63.15 ± 12.34 years. A total of 199 lesions were located in the periventricular white matter(n = 52), corpus callosum(n = 14), cerebellum(n = 29), basal ganglia and thalamus(n = 21), brainstem(n = 21) and gray-white matter junctions(n = 62). Percentage changes of apparent diffusion coefficient(ΔADC) and DKI-derived indices(fractional anisotropy [ΔFA], mean diffusivity [ΔMD], axial diffusivity [ΔD_a], radial diffusivity ΔDr, mean kurtosis [ΔMK], axial kurtosis [ΔK_a], and radial kurtosis [ΔK_r]) of each lesion were computed relative to the normal contralateral region. The results showed that(1) there was no significant difference in ΔADC, ΔMD, ΔD_a or ΔD_r among almost all locations.(2) There was significant difference in ΔMK among almost all locations(except basal ganglia and thalamus vs. brain stem; basal ganglia and thalamus vs. gray-white matter junctions; and brainstem vs. gray-white matter junctions.(3) The degree of change in diffusional kurtosis in descending order was as follows: corpus callosum > periventricular white matter > brainstem > gray-white matter junctions > basal ganglia and thalamus > cerebellum. In conclusion, DKI could reveal the differences in microstructure changes among various locations affected by acute ischemic stroke, and performed better than diffusivity among all groups. 展开更多
关键词 nerve REGENERATION APPARENT DIFFUSION coefficient DIFFUSION weighted IMAGING DIFFUSION KURTOSIS IMAGING acute ischemic stroke mean KURTOSIS microstructure changes white matter 1.5 TESLA magnetic resonance system neural REGENERATION
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Mapping Fear-Related Neural Activity and Circuitry Changes Following Prophylactic Administration of(R,S)-Ketamine and(2S,6S)-Hydroxynorketamine
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作者 Minzhu Li Li Cheng 《Neuroscience Bulletin》 2025年第5期925-928,共4页
Fear memory,a predictive and protective mechanism in potentially hostile environments,elicits defensive behavioral responses that have evolved to help organisms avoid harm and ensure survival.However,excessive fear me... Fear memory,a predictive and protective mechanism in potentially hostile environments,elicits defensive behavioral responses that have evolved to help organisms avoid harm and ensure survival.However,excessive fear memories may contribute to the onset of various psychological disorders,such as panic disorder,phobias,and post-traumatic stress disorder(PTSD). 展开更多
关键词 fear memories prophylactic administration psychological disorderssuch fear memorya fear related circuitry changes panic disorderphobiasand neural activity
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New Global Ideological Trends in the Era of Unprecedented Changes and China’s Diplomatic Responses
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作者 Lu Jing Lin Yiping 《China International Studies》 2025年第2期5-31,共27页
Transformations of the world unseen in a century are unfolding at a faster pace.Changes of the world,of our times,and of the historical trajectory are taking place in ways like never before.As the new round of technol... Transformations of the world unseen in a century are unfolding at a faster pace.Changes of the world,of our times,and of the historical trajectory are taking place in ways like never before.As the new round of technological revolution and industrial transformation advances,the international power structure and world order are undergoing tectonic realignments and constantly being reshaped.The protracted Ukraine crisis and the escalating Palestinian-Israeli conflict exemplify the intensification of major-power strategic rivalries and geopolitical conflicts.At the same time,non-traditional security issues are getting severe and more deeply intertwined with traditional security.Challenges such as climate change,cybersecurity,energy security,and food security are becoming critical global issues which confront humanity with unprecedented threats and herald a new era of instability and transformation for the world’s development. 展开更多
关键词 world transformations tectonic realignments industrial transformation technological revolution global ideological trends ukraine crisis Chinas diplomatic responses unprecedented changes
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Dynamic changes of behaviors, dentate gyrus neurogenesis and hippocampal miR-124 expression in rats with depression induced by chronic unpredictable mild stress 被引量:15
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作者 Yun-Ling Huang Ning-Xi Zeng +5 位作者 Jie Chen Jie Niu Wu-Long Luo Ping Liu Can Yan Li-Li Wu 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第6期1150-1159,共10页
The depression-like behavior phenotype,neurogenesis in the dentate gyrus and miR-124 expression in the hippocampus are the focus of current research on the pathogenesis of depression and antidepressant therapy.The pre... The depression-like behavior phenotype,neurogenesis in the dentate gyrus and miR-124 expression in the hippocampus are the focus of current research on the pathogenesis of depression and antidepressant therapy.The present study aimed to clarify the dynamic changes of depression-like behavior,dentate gyrus neurogenesis and hippocampal miR-124 expression during depression induced by chronic stress to reveal pathological features at different stages of depression and to further provide insight into depression treatment.Chronic unpredictable mild stress depression models were established by exposing Sprague-Dawley rats to various mild stressors,including white noise,thermal swimming,stroboscopic illumination,soiled cages,pairing with three other stressed animals,cold swimming,tail pinch,restraint and water and food deprivation.Chronic unpredictable mild stress model rats underwent dynamic observation from 1 to 8 weeks and were compared with a control group(normal feeding without any stressors).To observe changes in the depression-like behavior phenotype during chronic unpredictable mild stress-induced depression,a sucrose preference test was used to evaluate the degree of anhedonia.An open-field test was used to evaluate locomotor activity and anxiety status.Compared with the control group,chronic unpredictable mild stress rats lost weight but did not have a depression-like behavioral phenotype at 1-4 weeks.Chronic unpredictable mild stress rats presented decreased sucrose preference and locomotor activity at 5-8 weeks.In addition,chronic unpredictable mild stress rats did not have significant anxiety-like behavior during 1-8 weeks of modeling.To observe neurogenesis dysfunctions and changes in neuronal number in the dentate gyrus during chronic unpredictable mild stress-induced depression,markers(DCX and DCX/BrdU)of neural proliferation and differentiation and the neuronal marker NeuN were assessed by immunofluorescence.Compared with the control group,neurogenesis and the neuronal number in the dentate gyrus did not change from 2 to 6 weeks;however,neural proliferation and differentiation in the dentate gyrus decreased,and the number of neurons decreased until the eighth week in the chronic unpredictable mild stress group.Real-time quantitative reverse transcription polymerase chain reaction assays and fluorescence in situ hybridization were used to measure the expression of hippocampal miR-124 during chronic unpredictable mild stress-induced depression.The results showed that the expression of hippocampal miR-124 was unchanged during the first 4 weeks but increased from 5 to 6 weeks and decreased from 7 to 8 weeks compared with the control group.These findings indicate that during chronic unpredictable mild stress-induced depression,the behavioral phenotype,miR-124 expression in the hippocampus,neurogenesis in the dentate gyrus and neuronal numbers showed dynamic changes,which suggested that various pathological changes occur at different stages of depression.All experimental procedures and protocols were approved by the Experimental Animal Ethics Committee of Guangzhou University of Chinese Medicine of China in March 2015. 展开更多
关键词 chronic unpredictable MILD stress model continuous observation DEPRESSION depression-like behavior dynamic changes hippocampus miR-124 NEUROGENESIS DYSFUNCTION NEURONAL loss
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Assessing the Impacts of Land Use and Land Cover Changes on Hydrology of the Mbarali River Sub-Catchment. The Case of Upper Great Ruaha Sub-Basin, Tanzania 被引量:1
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作者 Edmund Mutayoba Japhet J. Kashaigili +2 位作者 Frederick C. Kahimba Winfred Mbungu Nyemo A. Chilagane 《Engineering(科研)》 2018年第9期616-635,共20页
Intensification of agricultural land use and population growth from 1990-2017 has caused changes in land cover and land use of the Mbarali River sub-catchment which is located in the Upper Great Ruaha Sub basin, Tanza... Intensification of agricultural land use and population growth from 1990-2017 has caused changes in land cover and land use of the Mbarali River sub-catchment which is located in the Upper Great Ruaha Sub basin, Tanzania. This has affected the magnitude of the surface runoff, total water yield and the groundwater flow. This study assesses the impacts of the land cover and land use changes on the stream flows and hydrological water balance components (surface runoff, water yield, percolation and actual evapotranspiration). The land use and land cover (LULC) maps for three window period snapshots, 1990, 2006 and 2017 were created from Landsat TM and OLI_TIRS with the help of QGIS version 2.6. Supervised classification was used to generate LULC maps using the Maximum Likelihood Algorithm and Kappa statistics for assessment of accuracy. SWAT was set up and run to simulate stream flows and hydrological water balance components. The assessment of the impacts of land use and land cover changes on stream flows and hydrological water balance component was performed by comparing hydrological parameters simulated by SWAT using land use scenarios of 2006 and 2017 against the baseline land use scenario of 1990. Accuracy of LULC classification was good with Kappa statistics ranging between 0.9 and 0.99. There was a drastic increase in areal coverage of cultivated land, for periods 1990-2006 (5.84%) and 2006-2017 (12.05%) compared to other LULC. During 2006 and 2017 surface runoff increased by 4% and 9% respectively;however, water yield increased by only 0.5% compared to 1990 baseline period. This was attributed to increased proportion of cultivated land in the sub-catchment which has a high curve number (59.60) that indicates a higher runoff response and low infiltration rate. 展开更多
关键词 Geographic Information System (GIS) Mbarali River Sub-Catchment Land Use and Cover Change Soil and WATER Assessment Tool (SWAT) WATER Balance Stream Flow
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Mapping of moraine dammed glacial lakes and assessment of their areal changes in the central and eastern Himalayas using satellite data 被引量:3
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作者 Sazeda BEGAM Dhrubajyoti SEN 《Journal of Mountain Science》 SCIE CSCD 2019年第1期77-94,共18页
The relatively rapid recession of glaciers in the Himalayas and formation of moraine dammed glacial lakes(MDGLs) in the recent past have increased the risk of glacier lake outburst floods(GLOF) in the countries of Nep... The relatively rapid recession of glaciers in the Himalayas and formation of moraine dammed glacial lakes(MDGLs) in the recent past have increased the risk of glacier lake outburst floods(GLOF) in the countries of Nepal and Bhutan and in the mountainous territory of Sikkim in India. As a product of climate change and global warming, such a risk has not only raised the level of threats to the habitation and infrastructure of the region, but has also contributed to the worsening of the balance of the unique ecosystem that exists in this domain that sustains several of the highest mountain peaks of the world. This study attempts to present an up to date mapping of the MDGLs in the central and eastern Himalayan regions using remote sensing data, with an objective to analyse their surface area variations with time from 1990 through 2015, disaggregated over six episodes. The study also includes the evaluation for susceptibility of MDGLs to GLOF with the least criteria decision analysis(LCDA). Forty two major MDGLs, each having a lake surface area greater than 0.2 km2, that were identified in the Himalayan ranges of Nepal, Bhutan, and Sikkim, have been categorized according to their surface area expansion rates in space and time. The lakes have been identified as located within the elevation range of 3800 m and6800 m above mean sea level(a msl). With a total surface area of 37.9 km2, these MDGLs as a whole were observed to have expanded by an astonishing 43.6% in area over the 25 year period of this study. A factor is introduced to numerically sort the lakes in terms of their relative yearly expansion rates, based on their interpretation of their surface area extents from satellite imageries. Verification of predicted GLOF events in the past using this factor with the limited field data as reported in literature indicates that the present analysis may be considered a sufficiently reliable and rapid technique for assessing the potential bursting susceptibility of the MDGLs. The analysis also indicates that, as of now, there are eight MDGLs in the region which appear to be in highly vulnerable states and have high chances in causing potential GLOF events anytime in the recent future. 展开更多
关键词 GLACIER RETREAT LAKES MAPPING MORAINE dammed GLACIAL lake(MDGL) Surface area change of LAKES Landsat imagery data Least criteria decision analysis(LCDA)
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Exploring the spatiotemporal heterogeneity of vegetation changes in subtropical humid karst region under CO_(2)fertilization 被引量:1
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作者 CHEN Meng ZHOU Qiuwen +1 位作者 PENG Dawei YAN Weihong 《Journal of Geographical Sciences》 2025年第1期65-87,共23页
Terrestrial ecosystems heavily depend on vegetation,which responds to carbon dioxide(CO_(2))fertilization in hot and humid regions.The subtropical humid karst region is a hot and humid region;whether and to what exten... Terrestrial ecosystems heavily depend on vegetation,which responds to carbon dioxide(CO_(2))fertilization in hot and humid regions.The subtropical humid karst region is a hot and humid region;whether and to what extent CO_(2)fertilization affects vegetation changes in such regions remains unclear.In this study,we investigated the degree to which CO_(2)fertilization influences vegetation changes,along with their spatial and temporal differences,in the subtropical humid karst region using time-lag effect analysis,a random forest model,and multiple regression analysis.Results showed that CO_(2)fertilization plays an important role in vegetation changes,exhibiting clear spatial variations across different geomorphological zones,with its degree of influence ranging mainly between 11%and 25%.The highest contribution of CO_(2)fertilization was observed in the karst basin and non-karstic region,whereas the lowest contribution was found in the karst plateau region.Previous studies have primarily attributed vegetation changes in subtropical humid karst region to ecological engineering,leading to an overestimation of its contribution to these changes.The findings of this study enhance the understanding of the mechanism of vegetation changes in humid karst region and provide theoretical and practical insights for ecological and environmental protection in these regions. 展开更多
关键词 KARST vegetation changes NDVI driving factors carbon dioxide FERTILIZATION
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Modeling geologically abrupt climate changes in the Miocene: Potential effects of high-latitudinal salinity changes
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作者 Bernd J. Haupt Dan Seidov 《Natural Science》 2012年第3期149-158,共10页
The cooling of the Cenozoic, including the Miocene epoch, was punctuated by many geologically abrupt warming and cooling episodes— strong deviations from the cooling trend with time span of ten to hundred thousands o... The cooling of the Cenozoic, including the Miocene epoch, was punctuated by many geologically abrupt warming and cooling episodes— strong deviations from the cooling trend with time span of ten to hundred thousands of years. Our working hypothesis is that some of those warming episodes at least partially might have been caused by dynamics of the Antarctic Ice Sheet, which, in turn, might have caused strong changes of sea surface salinity in the Miocene Southern Ocean. Feasibility of this hypothesis is explored in a series of offline-coupled ocean-atmosphere computer experiments. The results suggest that relatively small and geologically short-lived changes in freshwater balance in the Southern Ocean could have significantly contributed to at least two prominent warming episodes in the Miocene. Importantly, the scenario-based experiments also suggest that the Southern Ocean was more sensitive to the salinity changes in the Miocene than today, which can attributed to the opening of the Central American Isthmus as a major difference between the Miocene and the present-day ocean-sea geometry. 展开更多
关键词 Cenozoic MIOCENE Palao-Climate MODELING Community CLIMATE MODEL 3.6 Modular Ocean MODEL 2.2 Meridional OVERTURNING Freshwater Balance High-Latitudinal Salinity changes
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Climate Changes: How the Atmosphere Really Works
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作者 Ernani Sartori 《Open Journal of Applied Sciences》 2015年第4期151-168,共18页
Top concepts adopted by the current science on climate changes or atmospheric warming are not in agreement with the first principles of the physics. This paper presents a new understanding on the atmospheric behaviors... Top concepts adopted by the current science on climate changes or atmospheric warming are not in agreement with the first principles of the physics. This paper presents a new understanding on the atmospheric behaviors. For example, the radiation is not the only factor that influences the air temperature, as the law of conservation of energy defines and as shown physically and mathematically in this article. The Sun is not the only heat source for the atmosphere because there is generation of heat at the Earth’s surface by human activities. It is also shown that the water vapor is not a null effect and that the water vapor cannot be removed from the atmosphere for air temperature, greenhouse effect and climate changes considerations, in contrast to the current literature beliefs. The “feedback” concept is unfounded and invalid. The literature also says that “water vapor increases as the Earth’s atmosphere warms”, but this is also incorrect. The above equivocated understanding is accompanied by another one which believes that more water evaporates if the air temperature increases, but it is not in this way. These demonstrations and other authors’ surveys showing that in the last decades the planet became wetter eliminate the literature concept that the water vapor does not have influence on the atmospheric warming/cooling. The conventional water cycle is related to the mass of water (mass of evaporation mass of precipitation) and then the physical and mathematical principles of the new hydrological cycle that includes the direct human influence are shown. The same is done for the carbon cycle. It is solved the problem on why the wind speed on Venus is very high above the cloud deck while it is stagnant below it, being this the same physical principle valid for the Earth’s cloud cover. In the atmosphere, all the corresponding principles are the same, only their amounts change. It is demonstrated that the CO2 is not decisive for building and changing the temperatures of Venus, Mars, Mercury, Jupiter and Earth. Ice cores are not valid for “determining” “past” temperatures of the planet, because the mass of their air bubbles may be old, but the corresponding temperatures are not. 展开更多
关键词 Climate Change Global WARMING Evaporation Wind Temperature Radiation Precipitation Rain GREENHOUSE Effect HYDROLOGICAL Cycle Cloud Cover Ice CORES Planets
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In vivo imaging of structural,metabolic and functional brain changes in glaucoma 被引量:3
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作者 Anisha Kasi Muneeb A.Faiq Kevin C.Chan 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第3期446-449,共4页
Glaucoma, the world's leading cause of irreversible blindness, is a condition for which elevated intraocular pressure is currently the only modifiable risk factor. However, the disorder can continue to progress ev... Glaucoma, the world's leading cause of irreversible blindness, is a condition for which elevated intraocular pressure is currently the only modifiable risk factor. However, the disorder can continue to progress even at reduced intraocular pressure. This indicates additional key factors that contribute to the etiopathogenesis. There has been a growing amount of literature suggesting glaucoma as a neurodegenerative disease of the visual system. However, it remains debatable whether the observed pathophysiological conditions are causes or consequences. This review summarizes recent in vivo imaging studies that helped advance the understanding of early glaucoma involvements and disease progression in the brains of humans and experimental animal models. In particular, we focused on the non-invasive detection of early structural and functional brain changes before substantial clinical visual field loss in glaucoma patients; the eye-brain interactions across disease severity; the metabolic changes occurring in the brain's visual system in glaucoma; and, the widespread brain involvements beyond the visual pathway as well as the potential behavioral relevance. If the mechanisms of glaucomatous brain changes are reliably identified, novel neurotherapeutics that target parameters beyond intraocular pressure lowering can be the promise of the near future, which would lead to reduced prevalence of this irreversible but preventable disease. 展开更多
关键词 GLAUCOMA INTRAOCULAR pressure eye-brain-behavior relationship irreversible BLINDNESS magnetic resonance imaging METABOLIC BRAIN changes sensitivity disease progression
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Biochemical changes in phenols,flavonoids,tannins,vitamin E,β-carotene and antioxidant activity during soaking of three white sorghum varieties 被引量:7
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作者 Abd El-Moneim MR Afify Hossam S El-Beltagi +1 位作者 Samiha M Abd El-Salam Azza A Omran 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2012年第3期203-209,共7页
Objective:To investigate the changes in total phenols,flavonoids,tannins,vitamin E, β-carotene and antioxidant activity during soaking of three white sorghum varieties.Methods: The changes in total phenols,total ilav... Objective:To investigate the changes in total phenols,flavonoids,tannins,vitamin E, β-carotene and antioxidant activity during soaking of three white sorghum varieties.Methods: The changes in total phenols,total ilavonoids,tannins,phenolic acids compounds,flavonoid components,vitamin E,P-carotene and antioxidant activity during soaking of sorghum grains were determined.Results:Total phenols,total flavonoids,tannins,vitamin E,P-carotene and antioxidant activity in raw sorghum were ranged from 109.21 to 116.70,45.91 to 54.69,1.39 to 21.79 mg/100 g,1.74 to 5.25,0.54 to 1.19 mg/kg and 21.72%to 27.69%and 25.29%to 31.97%,respectively. The above measured compounds were significantly decreased after soaking.p-Hydroxybenzoic acid,vanillic acid,syringic acid and cinnamic acid represent the major phenolic acids in Dorado variety.While ferulic acid,p-coumaric acid,gallic acid and caffeic acid represent the major phenolic acids in Shandaweel-6.On the other hand,protocatechuic acid represents the major phenolic acids in Giza-15.Regarding flavonoids components,Dorado was the highest variety in kampferol and naringenin while Shandaweel-6 was the highest variety in luteolin, apigenin,hypersoid,quercelin and christen.Finally,Giza-15 was the highest variety in catechin. Phenolic acids,flavonoid compounds and antioxidant activities were decreased after soaking. Conclusions:Sorghum varieties have moderate quantities from total phenols,total flavonoids, tannins,phenolic acids compounds,flavonoid components,vitamin E,P-carotene and antioxidant activity which decreased after soaking. 展开更多
关键词 SORGHUM SOAKING Total PHENOLS FLAVONOIDS TANNINS Vitamin E Β-CAROTENE Antioxidant activity Phenolic acids Flavonoid components Biochemical change
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Runoff changes and influencing factors in the Nyang River Basin in Xizang
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作者 CAO Liang DONG Shi +2 位作者 WANG Yuyan LI Xingran CAO Pengxi 《Journal of Mountain Science》 2025年第10期3706-3720,共15页
This study aims to construct a large-scale hydrological Variable Infiltration Capacity(VIC)model based on temperature and precipitation at high altitudes,while elucidating the applicability of the model for hydrologic... This study aims to construct a large-scale hydrological Variable Infiltration Capacity(VIC)model based on temperature and precipitation at high altitudes,while elucidating the applicability of the model for hydrological simulation and analyzing the factors affecting runoff volume.Runoff volume and runoff depth were simulated using the VIC model and its performance was evaluated.Meanwhile,the factors affecting runoff volume were analyzed using Spearman correlation.The following model sensitivity parameters were obtained based on the China Natural Runoff Grid Point Dataset(CNRD v1.0):The variable infiltration curve parameter was 0.3,the Dsmax fraction where non-linear baseflow begins was 0.02,the maximum baseflow velocity was 15 mm/d,the maximum soil moisture where non-linear baseflow occurred was 0.7,the second soil moisture layer thickness was 0.3,and the thickness of the third soil moisture layer was 1.5.The surface runoff values in the Nyang River basin were similar in the first and fourth quarters(1.05–2.27 mm and 2.38–4.77 mm,respectively),and the surface runoff values were similar in the second and third quarters when the surface runoff was greater(23.46–52.20 mm and 60.59–85.63 mm,respectively).Watershed area,temperature,and precipitation significantly influenced the amount of runoff from the Nyang River.The applicability of the model to the Nyang River basin was confirmed using two different rate models.In some areas,precipitation and temperature did not have a dominating influence on runoff.Although the VIC model has significant advantages in runoff simulation,it requires a wealth of meteorological,soil,and hydrological data that may be difficult to obtain in some areas. 展开更多
关键词 Runoff changes Nyang river VIC model Meteorological changes Spearman correlation
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Spatiotemporal Variations in Climatic Factors,Catchment Characteristic Induced Runoff Changes with Multi-Time Scales across the Contiguous United States
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作者 Xinglong Gong Shuping Du +1 位作者 Fengyu Li Yibo Ding 《Journal of Earth Science》 2025年第1期146-160,共15页
Previous works were mainly concentrated on long-term average runoff alterations,and extreme temperatures and watershed conditions are little analyzed.In this study,we collected gauged river flow and meteorological dat... Previous works were mainly concentrated on long-term average runoff alterations,and extreme temperatures and watershed conditions are little analyzed.In this study,we collected gauged river flow and meteorological data time series from 1916 to 2015 and 1941 to 2015 across the contiguous United States(CONUS)for 188 catchments to investigate the temporal trends and spatial features of runoff changes at multi-time scales.We also analyzed the relationships between runoff changes and climatic factors.Median descriptive statistics and Budyko coupled climate elasticity methods were used to calculate runoff elasticity in each time scale.The original Mann-Kendall trend test was used to test their trend significance in four time-scale(11,20,40,and 60 a),respectively.The results show that the trend of runoff changes is more significant in high time scales;total changes are heterogeneous over CONUS.After the 1970s,increases of up to 27%decade-1 were mainly concentrated in the mid-northern regions.Maximum temperature and catchment characteristics are vital factors for runoff alteration;runoff changes are independent of rainfall,and wet regions tend to have lower changes.These findings could help develop better regional water resource planning and management. 展开更多
关键词 catchment characteristics climate change slipping window runoff changes trend analysis runoff elasticity
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A Study on the Diagnostic Ability of MRI for Modic Changes and Endplate Sclerosis in the Lumbar Spine
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作者 Tuanmao Guo Yuan Xiao Yanli Xing 《Journal of Clinical and Nursing Research》 2025年第8期147-152,共6页
Objective:To investigate the diagnostic value of magnetic resonance imaging(MRI)in patients with Modic changes and endplate sclerosis of the lumbar spine.Methods:A total of 66 patients with lumbar spine diseases who u... Objective:To investigate the diagnostic value of magnetic resonance imaging(MRI)in patients with Modic changes and endplate sclerosis of the lumbar spine.Methods:A total of 66 patients with lumbar spine diseases who underwent MRI and CT diagnostic examinations at the hospital from May 2024 to April 2025 were included in this study.The MRI findings of Modic changes were compared between Type I and Type II patients,and the presence or absence of endplate sclerosis signals and the HU value ratio on CT were analyzed.The pathological characteristics of Modic changes in Type I and Type II patients were observed.The imaging features of Modic changes in patients with lumbar spine diseases were analyzed.Results:Modic changes were present in 34 patients,with a total of 204 endplates evaluated,of which 74 were affected.MRI classification showed:Type I in 8 cases(10.81%),Type I/II mixed in 10 cases(13.51%),Type II in 51 cases(68.92%),and Type II/III mixed in 5 cases(6.76%).In CT reconstruction images,26 endplates with Modic changes on MRI showed sclerosis in the vertebral body,presenting high-density sclerotic features.These sclerotic areas did not exhibit distinct signal characteristics on MRI but pathologically demonstrated Type II Modic changes concurrently with fatty degeneration and sclerosis;In patients with Modic changes of Type I and Type II,regardless of the presence or absence of endplate sclerosis,the sagittal T1/T2 signal intensity ratio showed no statistically significant difference(P>0.05).However,the HU value ratio in Type II changes with sclerotic regions(2.74±0.61)was significantly higher than that in regions without sclerosis(1.16±0.23),with a statistically significant difference(P<0.05).Conclusion:CT reconstruction images of patients with lumbar Modic changes clearly demonstrate endplate sclerosis,a phenomenon closely associated with the bone marrow repair process.MRI has limited sensitivity for detecting sclerosis,potentially due to the following factors:first,differences in the radiographic characterization of endplate mineral content;second,the specific influence of different Modic types on signal intensity.This suggests that MRI classification should be combined with CT features for comprehensive interpretation. 展开更多
关键词 Magnetic resonance imaging CT Lumbar spine Modic changes Endplate sclerosis Diagnostic value
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Temporal changes in computed tomography findings of a persimmon bezoar:A case report
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作者 Masaya Iwamuro Tomoki Yoshikawa +4 位作者 Tomohiro Kamio Shoichiro Hirata Katsunori Matsueda Daisuke Kametaka Motoyuki Otsuka 《World Journal of Clinical Cases》 2025年第18期72-77,共6页
BACKGROUND Gastric bezoars are masses of indigestible material that accumulate in the stomach,causing nausea,abdominal pain,and vomiting.Persimmon bezoars(diospyrobezoars),which comprise tannins and fibers from persim... BACKGROUND Gastric bezoars are masses of indigestible material that accumulate in the stomach,causing nausea,abdominal pain,and vomiting.Persimmon bezoars(diospyrobezoars),which comprise tannins and fibers from persimmons,are relatively rare but may cause significant gastric complications,including gastric outlet obstruction or ileus.Although computed tomography(CT)is a useful ima-ging tool,diagnosing bezoars can be challenging because their density is similar to that of food debris and gastric content.CASE SUMMARY Here,we report the case of a 72-year-old woman with a persimmon bezoar that was diagnosed using serial CT imaging and confirmed by endoscopy.CT perfor-med over several months revealed changes in the internal structure and density of the bezoar,suggesting progressive hardening.The patient had a history of a par-tial gastrectomy and excessive persimmon consumption,both of which are risk factors for bezoar formation.Endoscopic fragmentation of the bezoar successfully resolved symptoms.CONCLUSION Gastric bezoars,particularly persimmon bezoars,present diagnostic challenges because of their variable imaging characteristics.Serial CT can document tem-poral changes in bezoar density,potentially reflecting changes in hardness.Early diagnosis and endoscopic treatment are essential for effective management,particularly in patients with predisposing factors.This case underscores the im-portance of considering bezoars in the differential diagnosis of gastric masses,and highlights the value of CT for monitoring changes in bezoar characteristics over time. 展开更多
关键词 Computed tomography Endoscopic treatment Gastric bezoar Persimmon bezoar Temporal changes Case report
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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 ratestate stress transfer model seismogenic zone megathrust failure
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Research on Changes in the Emotions and Behavior of School-Refusing Children With Water-Based Nail Treatments-Intervention in a Place for School-Refusing Children and Examination of Its Effects
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作者 Mizuno Yuko Sakai Koji 《Psychology Research》 2025年第2期73-82,共10页
This study examined the positive changes that water-based nail treatments can bring to emotions and behavior in children who do not attend school and use a place for school-refusing children.Children who do not attend... This study examined the positive changes that water-based nail treatments can bring to emotions and behavior in children who do not attend school and use a place for school-refusing children.Children who do not attend school and use a place for school-refusing children were given water-based nail treatments about once a week for three months.In addition,the parents of these children were asked to respond to questions about their children’s daily activities.The results showed that natural communication through nail treatments significantly increased positive emotions.However,continued nail treatments did not reduce the children’s problem behaviors.Some children returned to school,while others continued not attending school.Increased frequency of visits and number of treatments confirmed the promotion of communication.It was suggested that building positive relationships with family and supporters is important for achieving sustained effects from nail treatments.This study showed that nail treatments are a useful tool for promoting positive emotions,self-acceptance,and social skills,and may contribute to the emotional growth and social interest of children who do not attend school. 展开更多
关键词 interventional study children not attending school water-based nail polish Diagram of Mood States(DMS) Child Behavior Checklist(CBCL) emotional and behavioral changes
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Comparison of Digital Maps: Recognition and Quantitative Measure of Changes
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作者 Lev Spivak Ivan Spivak +1 位作者 Alexey Sokolov Sergey Voinov 《Journal of Geographic Information System》 2014年第5期415-422,共8页
A new methodology of comparing digital raster maps was proposed which allows not only detecting changes in the maps, but also obtaining quantitative measures of the importance of selected differences. Procedure of obj... A new methodology of comparing digital raster maps was proposed which allows not only detecting changes in the maps, but also obtaining quantitative measures of the importance of selected differences. Procedure of object interpretation of satellite images and forming of OMT (Object Map of Territory) is described. A list of allowable differences between two OMTs is defined. Two steps technique of quantitative measuring is proposed. At the first stage functions are constructed for calculating local measures of differences in the amount, areas and locations of objects on the map, as well as relations between the objects. In the second stage local measures are used to calculate the integral measure in order to get generalized assessment of difference between maps. The methods for constructing functions which calculate local and integral measures of differences are described. Examples of comparing and measuring the differences between OMTs are provided. Obtained results by utilizing this technique can be used to analyze trends, forecast of development and might be helpful for choosing most efficient scenarios for sustainable spatial planning and land management. 展开更多
关键词 MAPS COMPARISON Object Map of TERRITORY Change Detection Local MEASURE of DIFFERENCE INTEGRAL MEASURE of DIFFERENCE Sustainable Spatial Planning and Land Management
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Macular microvascular and structural changes on optical coherence tomography angiography in atypical optic neuritis 被引量:1
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作者 Chinmay Mahatme Madhurima Kaushik +2 位作者 Veerappan Rathinasabapathy Saravanan Karthik Kumar Virna M Shah 《World Journal of Methodology》 2025年第1期88-94,共7页
BACKGROUND Atypical optic neuritis,consisting of neuromyelitis optica spectrum disorders(NMOSD)or myelin oligodendrocyte glycoprotein antibody disease(MOGAD),has a very similar presentation but different prognostic im... BACKGROUND Atypical optic neuritis,consisting of neuromyelitis optica spectrum disorders(NMOSD)or myelin oligodendrocyte glycoprotein antibody disease(MOGAD),has a very similar presentation but different prognostic implications and longterm management strategies.Vascular and metabolic factors are being thought to play a role in such autoimmune neuro-inflammatory disorders,apart from the obvious immune mediated damage.With the advent of optical coherence tomography angiography(OCTA),it is easy to pick up on these subclinical macular microvascular and structural changes.AIM To study the macular microvascular and structural changes on OCTA in atypical optic neuritis.METHODS This observational cross-sectional study involved 8 NMOSD and 17 MOGAD patients,diagnosed serologically,as well as 10 healthy controls.Macular vascular density(MVD)and ganglion cell+inner plexiform layer thickness(GCIPL)were studied using OCTA.RESULTS There was a significant reduction in MVD in NMOSD and MOGAD affected as well as unaffected eyes when compared with healthy controls.NMOSD and MOGAD affected eyes had significant GCIPL thinning compared with healthy controls.NMOSD unaffected eyes did not show significant GCIPL thinning compared to healthy controls in contrast to MOGAD unaffected eyes.On comparing NMOSD with MOGAD,there was no significant difference in terms of MVD or GCIPL in the affected or unaffected eyes.CONCLUSION Although significant microvascular and structural changes are present on OCTA between atypical optic neuritis and normal patients,they could not help in differentiating between NMOSD and MOGAD cases. 展开更多
关键词 Optical coherence tomography angiography Atypical optic neuritis Macular microvascular changes Neuromyelitis optica spectrum disorders Myelin oligodendrocyte glycoprotein antibody disorder
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Monitoring Intra-annual Spatiotemporal Changes in Urban Heat Islands in 1449 Cities in China Based on Remote Sensing 被引量:3
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作者 LI Yuanzheng WANG Lan +2 位作者 ZHANG Liping LIU Min ZHAO Guosong 《Chinese Geographical Science》 SCIE CSCD 2019年第6期905-916,共12页
This study aimed to accurately study the intra-annual spatiotemporal variation in the surface urban heat island intensities(SUHIIs) in 1449 cities in China.First, China was divided into five environmental regions.Then... This study aimed to accurately study the intra-annual spatiotemporal variation in the surface urban heat island intensities(SUHIIs) in 1449 cities in China.First, China was divided into five environmental regions.Then, the SUHIIs were accurately calculated based on the modified definitions of the city extents and their corresponding nearby rural areas.Finally, we explored the spatiotemporal variation of the mean, maximum, and minimum values, and ranges of SUHIIs from several aspects.The results showed that larger annual mean daytime SUHIIs occurred in hot-humid South China and cold-humid northeastern China, and the smallest occurred in arid and semiarid west China.The seasonal order of the SUHIIs was summer > spring > autumn > winter in all the temperate regions except west China.The SUHIIs were obviously larger during the rainy season than the dry season in the tropical region.Nevertheless, significant differences were not observed between the two seasons within the rainy or dry periods.During the daytime, the maximum SUHIIs mostly occurred in summer in each region, while the minimum occurred in winter.A few cold island phenomena existed during the nighttime.The maximum SUHIIs were generally significantly positively correlated with the minimum SUHIIs during the daytime, nighttime and all-day in all environmental regions throughout the year and the four seasons.Moreover, significant correlation scarcely existed between the daytime and nighttime ranges of the SUHIIs.In addition, the daytime SUHIIs were also insignificantly correlated with the nighttime SUHIIs in half of the cases. 展开更多
关键词 SURFACE urban heat ISLAND intensities(SUHIIs) land SURFACE temperature(LST) SEASONAL changes maximum and minimum SUHII cold ISLAND China
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