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Differential distribution of PINK1 and Parkin in the primate brain implies distinct roles
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作者 Yanting Liu Wei Huang +8 位作者 Jiayi Wen Xin Xiong Ting Xu Qi Wang Xiusheng Chen Xianxian Zhao Shihua Li Xiaojiang Li Weili Yang 《Neural Regeneration Research》 SCIE CAS 2025年第4期1124-1134,共11页
The vast majority of in vitro studies have demonstrated that PINK1 phosphorylates Parkin to work together in mitophagy to protect against neuronal degeneration.However,it remains largely unclear how PINK1 and Parkin a... The vast majority of in vitro studies have demonstrated that PINK1 phosphorylates Parkin to work together in mitophagy to protect against neuronal degeneration.However,it remains largely unclear how PINK1 and Parkin are expressed in mammalian brains.This has been difficult to address because of the intrinsically low levels of PINK1 and undetectable levels of phosphorylated Parkin in small animals.Understanding this issue is critical for elucidating the in vivo roles of PINK1 and Parkin.Recently,we showed that the PINK1 kinase is selectively expressed as a truncated form(PINK1–55)in the primate brain.In the present study,we used multiple antibodies,including our recently developed monoclonal anti-PINK1,to validate the selective expression of PINK1 in the primate brain.We found that PINK1 was stably expressed in the monkey brain at postnatal and adulthood stages,which is consistent with the findings that depleting PINK1 can cause neuronal loss in developing and adult monkey brains.PINK1 was enriched in the membrane-bound fractionations,whereas Parkin was soluble with a distinguishable distribution.Immunofluorescent double staining experiments showed that PINK1 and Parkin did not colocalize under physiological conditions in cultured monkey astrocytes,though they did colocalize on mitochondria when the cells were exposed to mitochondrial stress.These findings suggest that PINK1 and Parkin may have distinct roles beyond their well-known function in mitophagy during mitochondrial damage. 展开更多
关键词 NEURODEGENERATION PARKIN Parkinson’s disease PINK1 subcellular distribution
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Neural stem cell-derived exosomes promote mitochondrial biogenesis and restore abnormal protein distribution in a mouse model of Alzheimer's disease 被引量:1
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作者 Bo Li Yujie Chen +10 位作者 Yan Zhou Xuanran Feng Guojun Gu Shuang Han Nianhao Cheng Yawen Sun Yiming Zhang Jiahui Cheng Qi Zhang Wei Zhang Jianhui Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1593-1601,共9页
Mitochondrial dysfunction is a hallmark of Alzheimer’s disease.We previously showed that neural stem cell-derived extracellular vesicles improved mitochondrial function in the cortex of AP P/PS1 mice.Because Alzheime... Mitochondrial dysfunction is a hallmark of Alzheimer’s disease.We previously showed that neural stem cell-derived extracellular vesicles improved mitochondrial function in the cortex of AP P/PS1 mice.Because Alzheimer’s disease affects the entire brain,further research is needed to elucidate alterations in mitochondrial metabolism in the brain as a whole.Here,we investigated the expression of several important mitochondrial biogenesis-related cytokines in multiple brain regions after treatment with neural stem cell-derived exosomes and used a combination of whole brain clearing,immunostaining,and lightsheet imaging to clarify their spatial distribution.Additionally,to clarify whether the sirtuin 1(SIRT1)-related pathway plays a regulatory role in neural stem cell-de rived exosomes interfering with mitochondrial functional changes,we generated a novel nervous system-SIRT1 conditional knoc kout AP P/PS1mouse model.Our findings demonstrate that neural stem cell-de rived exosomes significantly increase SIRT1 levels,enhance the production of mitochondrial biogenesis-related fa ctors,and inhibit astrocyte activation,but do not suppress amyloid-βproduction.Thus,neural stem cell-derived exosomes may be a useful therapeutic strategy for Alzheimer’s disease that activates the SIRT1-PGC1αsignaling pathway and increases NRF1 and COXIV synthesis to improve mitochondrial biogenesis.In addition,we showed that the spatial distribution of mitochondrial biogenesis-related factors is disrupted in Alzheimer’s disease,and that neural stem cell-derived exosome treatment can reverse this effect,indicating that neural stem cell-derived exosomes promote mitochondrial biogenesis. 展开更多
关键词 Alzheimer’s disease mitochondrial biogenesis neural stem cell-derived exosome sIRT1-PGC1α regional brain distribution whole brain clearing and imaging
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Spatiotemporal Distributions of Bacterioplankton Communities in the Qiantang River(Hangzhou Section),China
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作者 XU Jiaojiao ZHAO Li +4 位作者 LUKWAMBE Betina NICHOLAUS Regan ZHU Jinyong YANG Wen ZHENG Zhongming 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第4期1102-1114,共13页
The spatial and temporal distribution of bacterioplankton communities plays a vital role in understanding the ecological dynamics and health of aquatic ecosystems.In this study,we conducted a comprehensive investigati... The spatial and temporal distribution of bacterioplankton communities plays a vital role in understanding the ecological dynamics and health of aquatic ecosystems.In this study,we conducted a comprehensive investigation of the bacterioplankton communities in the Qiantang River(Hangzhou section).Water samples were collected quarterly from seven sites over a one-year period.Physical and chemical parameters,including dissolved oxygen(DO),water temperature(WT),chemical oxygen demand(COD),nitrite(NO_(2)^(-)),active phosphate(PO_(4)^(3-))and other indices were determined.In this study,theαdiversity,βdiversity and abundance differences of bacterial communities were investigated using 16S rRNA high-throughput sequencing analysis.The spatial and temporal distribution characteristics and main driving factors of the bacterioplankton community structure and diversity were discussed.The results showed that a total of 57 phyla were detected in the bacterioplankton community,among which Proteobacteria and Actinomycetes were the two dominant groups with the highest relative abundance.The results of PCoA based on Bray-Curtis distance showed that the sampling season had a slightly greater effect on the changes in bacterioplankton community structure in the Qiantang River.Mantel and partial Mantel test showed that environmental variables(Mantel r=0.6739,P<0.0001;partial Mantel r=0.507,P=0.0001)were more important than geographical distance(Mantel r=0.5322,P<0.001;partial Mantel r=0.1563,P=0.001).The distance attenuation model showed that there was significant distance attenuation in all four seasons,and the maximum limit of bacterial community diffusion was found in spring.RDA analysis showed that nine environmental factors,including COD,WT and DO,significantly affected community distribution(P<0.05).This study provides valuable insights into the spatial and temporal distribution characteristics of bacterioplankton communities,shedding light on their ecological roles in the Qiantang River.The information obtained can guide future research on the interactions between bacterioplankton and their environment,enabling the development of effective conservation strategies and sustainable management practices for aquatic ecosystems. 展开更多
关键词 Qiantang River bacterioplankton community spatial and temporal distribution 16s rRNA range attenuation
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A Model of the Fatigue Life Distribution of Composite Laminates Based on Their Static Strength Distribution 被引量:7
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作者 吴富强 姚卫星 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2008年第3期241-246,共6页
The reasons of the static strength dispersion and the fatigue life dispersion of composite laminates are analyzed in this article. It is concluded that the inner original defects, which derived from the manufacturing ... The reasons of the static strength dispersion and the fatigue life dispersion of composite laminates are analyzed in this article. It is concluded that the inner original defects, which derived from the manufacturing process of composite laminates, are the common and major reason of causing the random distributions of the static strength and the fatigue life. And there is a correlative relation between the two distributions. With the study of statistical relationship between the fatigue loading and the fatigue life in the uniform confidence level and the same survival rate S-N curves of material, the relationship between the static strength distribution and the fatigue life distribution through a material S-N curve model has been obtained. And then the model which is used to describe the distributions of fatigue life of composites, based on their distributions of static strength, is set up. This model reasonably reflects the effects of the inner original defects on the static strength dispersion and on the fatigue life dispersion of composite laminates. The experimental data of three kinds of composite laminates are employed to verify this model, and the results show that this model can predict the random distributions of fatigue life for composites under any fatigue loads fairly well. 展开更多
关键词 COMPOsITE static strength fatigue life s-N curve random distribution
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高师院校学生会建设存在的问题与对策——基于Maslow's Hierarchy of Needs的探索
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作者 王胜 金梦吟 《软件导刊.教育技术》 2014年第7期30-34,共5页
由于高师院校学生会干部存在男女生比例失调及家庭经济困难生比例大等现象,分析了学生会建设中存在干部体制建设有待加强及培养欠缺可持续发展的观念等问题。以F师范学院为对象进行调查研究,依据马斯洛需求理论,提出以设计淘汰机制,实... 由于高师院校学生会干部存在男女生比例失调及家庭经济困难生比例大等现象,分析了学生会建设中存在干部体制建设有待加强及培养欠缺可持续发展的观念等问题。以F师范学院为对象进行调查研究,依据马斯洛需求理论,提出以设计淘汰机制,实现成就与价值为主的解决方案。 展开更多
关键词 高师学生会 学生会干部 Maslow’s HIERARCHY of needs
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Effect of nursing intervention based on Maslow's hierarchy of needs in patients with coronary heart disease interventional surgery 被引量:19
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作者 Ji-Xue Xu Lin-Xue Wu +1 位作者 Wei Jiang Gui-Hong Fan 《World Journal of Clinical Cases》 SCIE 2021年第33期10189-10197,共9页
BACKGROUND It is very important to provide effective nursing programs to regulate the physical and mental state of patients and to improve treatment compliance after interventional surgery for coronary heart disease(C... BACKGROUND It is very important to provide effective nursing programs to regulate the physical and mental state of patients and to improve treatment compliance after interventional surgery for coronary heart disease(CHD).AIM To explore the effect of a nursing intervention based on Maslow’s hierarchy of needs theory on patients with CHD undergoing percutaneous coronary intervention.METHODS Ninety-four patients with CHD undergoing interventional surgery in our hospital from January 2020 to February 2021 were randomly divided into a research group(n=47)and a control group(n=47).The control group received routine nursing,and the research group received a nursing intervention based on Maslow’s hierarchy of needs theory.The scores of self-efficacy,negative emotion[depression(SDS),anxiety(SAS)],intervention compliance(standardized medication,moderate exercise,healthy diet,and regular review),and nursing satisfaction were calculated before and after intervention for the two groups.RESULTS Before intervention,there was no significant difference in the scores of disease general management self-efficacy,disease management self-efficacy,and total self-efficacy between the two groups(P=0.795,0.479,and 0.659,respectively).After intervention,these three scores in the research group were higher than those in the control group(P<0.001).Before intervention,there was no significant difference in the scores of SAS and SDS between the two groups(P=0.149 and 0.347,respectively).After intervention,the scores of SAS and SDS in the research group were lower than those in the control group(P<0.001).The standardized drug use rate(97.87%),moderate exercise rate(97.87%),healthy diet rate(95.74%),and regular reexamination rate(97.87%)in the research group were higher than those in the control group(85.11%,82.98%,80.85%,and 87.23%,respectively)(P=0.027,0.014,0.025,and 0.049,respectively).Nursing job satisfaction in the research group(93.62%)was higher than that in the control group(78.72%)(P=0.036).CONCLUSION A nursing program based on Maslow’s hierarchy of needs theory can effectively alleviate negative emotion,enhance self-efficacy and intervention compliance,and ensure that the patients are highly satisfied with the nursing work. 展开更多
关键词 Maslow’s hierarchy of needs NURsING Coronary heart disease Interventional surgery COMPLIANCE
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Origin and Distribution of Hydrogen Sulfide in Oil-Bearing Basins,China 被引量:9
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作者 ZHU Guangyou ZHANG Shuichang LIANG Yingbo 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第6期1188-1201,共14页
The concentration of hydrogen sulfide gas (H2S) varies greatly in the oil-bearing basins of China, from zero to 90%. At present, oil and gas reservoirs with high H2S concentration have been discovered in three basin... The concentration of hydrogen sulfide gas (H2S) varies greatly in the oil-bearing basins of China, from zero to 90%. At present, oil and gas reservoirs with high H2S concentration have been discovered in three basins, viz. the Bohai Bay Basin, Sichuan Basin and the Tarim Basin, whereas natural gas with low H2S concentration has been found in the Ordos Basin, the Songliao Basin and the Junggar Basin. Studies suggest that in China H2S origin types are very complex. In the carbonate reservoir of the Sichuan Basin, the Ordos Basin and the Tarim Basin, as well as the carbonatedominated reservoir in the Luojia area of the Jiyang depression in the Bohai Bay Basin, Wumaying areas of the Huanghua depression, and Zhaolanzhuang areas of the Jizhong depression, the H2S is of Thermochemical Sulfate Reduction (TSR) origin. The H2S is of Bacterial Sulphate Reduction (BSR) origin deduced from the waterflooding operation in the Changheng Oilfield (placanticline oil fields) in the Songliao Basin. H2S originates from thermal decomposition of sulfur-bearing crude oil in the heavy oil area in the Junggar Basin and in the Liaohe heavy oil steam pilot area in the western depression of the Bohai Bay Basin. The origin types are most complex, including TSR and thermal decomposition of sulfcompounds among other combinations of causes. Various methods have been tried to identify the origin mechanism and to predict the distribution of H2S. The origin identification methods for H2S mainly comprise sulfur and carbon isotopes, reservoir petrology, particular biomarkers, and petroleum geology integrated technologies; using a combination of these applications can allow the accurate identification of the origins of H2S. The prediction technologies for primary and secondary origin of H2S have been set up separately. 展开更多
关键词 H2s TsR BsR distribution origin mechanism oil-bearing basins
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Customization Product Design Based on User's Emotion and Needs 被引量:3
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作者 金纯 张春林 刘文枝 《Defence Technology(防务技术)》 SCIE EI CAS 2005年第2期245-249,共5页
The paper presents a design method that ensures the ingenuity of the product form as well as the whole and exact expression of user’s needs. The key idea is to establish an automatic design system which can transform... The paper presents a design method that ensures the ingenuity of the product form as well as the whole and exact expression of user’s needs. The key idea is to establish an automatic design system which can transform the user’s language needs into the product features in real-time. A rifle was taken as a research instance and soldiers were chosen as evaluation customers. The theory of fuzzy set and semantic difference are adopted to evaluate the relationship between user’s needs and product features as well as their alternatives. FAHP (fuzzy analytic hierarchy process) is utilized to judge the user’s satisfactory forms. This method can also be applied to other product form designs. 展开更多
关键词 user’s needs product form CUsTOMIZATION fuzzy number
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Spatial Distribution of Mulberry Thrips,Pseudodendrothrips mori Niwa (Thysanoptera:Thripidae) 被引量:5
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作者 Shahram Hesami Kayvan Etebari +1 位作者 Hassan Pourbabaei Mohammad Mojtaba Kamelmanesh 《Zoological Research》 CAS CSCD 北大核心 2007年第3期265-270,共6页
Pseudodendrothrips mori is a serious pest to mulberry trees and its infestation affects the qualitative and quantitative characteristics of mulberry leaves consumed by silkworm. The spatial distribution of mulberry th... Pseudodendrothrips mori is a serious pest to mulberry trees and its infestation affects the qualitative and quantitative characteristics of mulberry leaves consumed by silkworm. The spatial distribution of mulberry thrips within plant and orchard was assessed using Taylor's power law and Morisita's index of dispersion. The results showed that P.mori populations were localized in certain parts of the trees and fields. Distribution of thrips within plant showed that the larval instars were located on lower canopy (leaves 5-10 from top) of trees but adults preferred the upper canopy (leaves 1-5 from top). The thrips density did not vary significantly among the leaf direction inside the trees. The thrips tended to be more accumulated on the trees located in East, South and North than in Center and West of orchard. The distributions of P.mori adults and larvae on the leaves were aggregated. 展开更多
关键词 Mulberry thrips Pseudodendrothrips mori spatial distribution Taylor's power law Iran
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Prognostic significance of red blood cell distribution width in gastrointestinal disorders 被引量:21
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作者 Hemant Goyal Giuseppe Lippi +3 位作者 Altin Gjymishka Bijo John Rajiv Chhabra Elizabeth May 《World Journal of Gastroenterology》 SCIE CAS 2017年第27期4879-4891,共13页
The red blood cell distribution width(RDW) is a routinely measured and automatically reported blood parameter,which reflects the degree of anisocytosis. Recently,the baseline RDW was found to have clinical significanc... The red blood cell distribution width(RDW) is a routinely measured and automatically reported blood parameter,which reflects the degree of anisocytosis. Recently,the baseline RDW was found to have clinical significance for assessing clinical outcome and severity of various pathological conditions including cardiovascular diseases,sepsis,cancers,leukemia,renal dysfunction and respiratory diseases. A myriad of factors,most of which ill-defined,have an impact on the red cell population dynamics(i.e.,production,maturation and turnover). A delay in the red blood cell clearance in pathological conditions represents one of the leading determinants of increased anisocytosis. Further study of RDW may reveal new insight into inflammation mechanisms. In this review,we specifically discuss the current literature about the association of RDW in various disease conditions involving the gastrointestinal and hepatobiliary systems. We also present some of the related measurements for their value in predicting clinical outcomes in such conditions. According to our data,RDW was found to be a valuable prognostic index in gastrointestinal disorders along with additional inflammatory biomarkers(i.e.,C reactive protein,erythrocyte sedimentation rate,and platelet count) and current disease severity indices used in clinical practice. 展开更多
关键词 Red blood cell distribution width HEPATITIs PANCREATITIs Inflammatory bowel diseases Crohn’s disease Ulcerative colitis Colon cancer Hepatocellular carcinoma Acute mesenteric ischemia Gastrointestinal diseases
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R/S ratio in lead Ⅱ, and the prognostic significance of red cell distribution width in acute coronary syndrome 被引量:1
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作者 Abuzer Coskun Sevki Hakan Eren 《World Journal of Clinical Cases》 SCIE 2019年第16期2217-2226,共10页
BACKGROUND In spite of developing medical technologies to discover the etiopathogenesis of diseases and developments in the treatment of coronary artery disease, acute coronary syndromes(ACS) continue to be the main c... BACKGROUND In spite of developing medical technologies to discover the etiopathogenesis of diseases and developments in the treatment of coronary artery disease, acute coronary syndromes(ACS) continue to be the main cause of mortality and morbidity worldwide. New cardiac biomarkers and techniques are needed to help provide rapid diagnosis in order to evaluate risk in coronary artery patients.AIM To evaluate the effects of R to S ratio(RSR) in the electrocardiograph of patients with ACS, from the point of the arising complication after myocardial infarction(MI), to three-vessel disease(TVD) and mortality.METHODS The data of 1,296 patients with ACS, who presented to the emergency department of our hospital with chest pain between January 2014 and December2018 and were admitted to the cardiology clinic, were retrospectively included in this cross-sectional cohort study. Patients with an RSR value less than I were assigned to group Ⅰ, while those with an RSR value greater than Ⅰ were assigned to group Ⅱ.RESULTS In our study, 466(35.9%) of the 1,296 patients, 357(38.3%) in group 1 and 109(29.9%) in group 2, were female, with a mean age of 61.56 ± 9.42. ST-elevation MI 573(44.2%), unstable angina(UA) 502(38.7%) and non ST-elevation MI 220(17%)were more prevalent in group Ⅰ. Acute anterior MI 263(20.3) in group Ⅰ, and acute inferior MI 184(14.2) in group Ⅱ was higher. Ischemic heart failure was the most common complication. In group Ⅱ, the red cell distribution width(RDW) was 15.42 ± 1.82, the gensini score was 48.39 ± 36.44, the left ventricular ejection fraction was 41.17 ± 10.41, the TVD was 111(8.5), and the mortality rate was 72(5.6), which was significantly higher than group Ⅰ RDW; in MI with ST and nonST-elevation, in TVD, mortality and complications were high and low in UA. In single and multivariate regression analyses, the variables were associated with ACS risk.CONCLUSION RSR levels may be an auxiliary predictive value in ACS in terms of complications developing after MI, TVD, and mortality. 展开更多
关键词 Acute CORONARY sYNDROME EMERGENCY DEPARTMENT R/s RATIO Red cell distribution WIDTH
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Species Diversity and Elevational Distribution of Amphibians in the Xianxialing and Wuyishan Mountain Ranges,Southeastern China 被引量:2
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作者 Zhiqiang CHEN Yun TANG +3 位作者 Yingying WANG Yindie LI Longhui LIN Guohua DING 《Asian Herpetological Research》 SCIE CSCD 2020年第1期44-55,共12页
The species diversity and altitudinal distribution of amphibians along an eleva tional gradient of 200-1600 m in the Xianxialing and Wuyishan Mountain Ranges in Southeastern China were investiga ted through time-const... The species diversity and altitudinal distribution of amphibians along an eleva tional gradient of 200-1600 m in the Xianxialing and Wuyishan Mountain Ranges in Southeastern China were investiga ted through time-constra ined visual surveys along 32 transect lines in 9 survey areas,in which the ha bitat types were also recorded.A total of 27 amphibian species belonging to 19 genera,7 families,and 2 orders were found.The species diversity of the amphibians plateaued at low elevation,and the altitudinal boundary of their distribution was at 800 m.Their species compositions were dissimilar in the two mountain ranges probably beca use the annual average temperature and annual rainfall were different in both areas.The eleva tional Rapoport's rule demonstrated that the species range size of the amphibians expanded as the elevation increased in both mountain ranges.The results of the cross species method supported the rule only when the influence of the low-frequency occurrence proba bility of an investigated species was excluded,whereas those of the Steven's method strongly corroborated the rule rega rdless of the incidental occurrence or absence of the species. 展开更多
关键词 AMPHIBIAN diversity altitudinal distribution Rapoport’s rule CROss-sPECIEs METHOD steven’s METHOD
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Distribution of ^3H—nicotine in Rat Tissues Under the Influence of Simulated Microgravity 被引量:6
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作者 PARIMAL CHOWDHURY MICHAEL E. SOULSBY AND JAMES N. PASLEY (Department of Physiology and Biophysics, University of Arkansas for Medical Scienses, Little Rock, Arkansas 72205, USA) 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1999年第2期103-109,共7页
Rat tail suspension offers a useful model to reproduce physiologic responses to weightlessness.The present study was conducted in the head-down-tilt(HDT) rat model to assess changes in metabolism of body tissues emp... Rat tail suspension offers a useful model to reproduce physiologic responses to weightlessness.The present study was conducted in the head-down-tilt(HDT) rat model to assess changes in metabolism of body tissues employing 3H-nicotine. Twelve male rats were used in the study. Half of the rats were tail suspended at 30°for two weeks on a 12/12 light/dark cycle. During this period,body weight, food and fluid intakes were measured. At term, animals were anesthetized and injected IV withe a solution contaming 4 microuries of micotine. After 90 min the animals were sacrificed, exsanguinated and tissues (brain,blood,trachea,salivary gland,lung,heart,esophagus,spleen, kidneys and testes) were harvested. The distribution of 3H-nicotine per gram of each tissue was determinded and ealeulated as percent of total injected radioactivity. Final body weights of suspended ammals were significantly (P < 0.0 5) lower than those of eontrols(309±21 vs 350±11g). 3HNicotine waw retained in greatest amounts by the kindneys, followed inorder by salivary glands, spleen, and gastrointestinal tissues. compared to non-suspended control, the tissue retention of nicotine in suspended animals was decreased in the following tissues:esphyagus (25 %), aorta (25%). fundus (25%), trachea (22%), adrenals (18%), spleen (17 %), and pancreas (12 %). The decreased retention of mcotine in tissues from suspended animals may be indicative of the fluid shifts and changes in blood flow to those tissue beds. The lack of differnces in nicotine retention in liver and kidney between control and suspended groups may implicate a normal metabolic function of these organs even under simulated weightlessness. 展开更多
关键词 GRAVITATION Animals Male NICOTINE RATs Rats sprague-Dawley Research support Non-U.s. Gov't Tissue distribution Tritium Weightlessness simulation
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Modeling and forecasting exchange rate volatility in Bangladesh using GARCH models:a comparison based on normal and Student's t-error distribution 被引量:2
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作者 S.M.Abdullah Salina Siddiqua +1 位作者 Muhammad Shahadat Hossain Siddiquee Nazmul Hossain 《Financial Innovation》 2017年第1期238-256,共19页
Background:Modeling exchange rate volatility has remained crucially important because of its diverse implications.This study aimed to address the issue of error distribution assumption in modeling and forecasting exch... Background:Modeling exchange rate volatility has remained crucially important because of its diverse implications.This study aimed to address the issue of error distribution assumption in modeling and forecasting exchange rate volatility between the Bangladeshi taka(BDT)and the US dollar($).Methods:Using daily exchange rates for 7 years(January 1,2008,to April 30,2015),this study attempted to model dynamics following generalized autoregressive conditional heteroscedastic(GARCH),asymmetric power ARCH(APARCH),exponential generalized autoregressive conditional heteroscedstic(EGARCH),threshold generalized autoregressive conditional heteroscedstic(TGARCH),and integrated generalized autoregressive conditional heteroscedstic(IGARCH)processes under both normal and Student’s t-distribution assumptions for errors.Results and Conclusions:It was found that,in contrast with the normal distribution,the application of Student’s t-distribution for errors helped the models satisfy the diagnostic tests and show improved forecasting accuracy.With such error distribution for out-of-sample volatility forecasting,AR(2)–GARCH(1,1)is considered the best. 展开更多
关键词 Exchange rate VOLATILITY ARCH GARCH student’s t Error distribution
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Distribution of constitutive nitric oxide synthase in the jejunum of adult rat 被引量:6
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作者 ChenYM QianZM 《World Journal of Gastroenterology》 SCIE CAS CSCD 2002年第3期537-539,共3页
AIM: To study the distribution of the constitutive nitric oxide synthase (NOS) in the jejunum of adult rat. METHODS: The distribution of endothelial NOS (eNOS) was detected by immunohistochemistry. Immunofluorescence ... AIM: To study the distribution of the constitutive nitric oxide synthase (NOS) in the jejunum of adult rat. METHODS: The distribution of endothelial NOS (eNOS) was detected by immunohistochemistry. Immunofluorescence histochemical dual staining technique were used for studying the distribution of neuronal NOS (nNOS) and eNOS. The dual stained slides were observed under a confocal laser scanning microscope. RESULTS: Positive neuronal NOS (nNOS) and endothelial NOS (eNOS) cells were found to be distributed in lamina propria of villi, and the epithelial cell was not stained. eNOS was mainly located in submucosal vascular endothelia, while nNOS was mainly situated in myenteric plexus. Some cells in the villi had both nNOS and eNOS. More than 80% of the cells were positive for both nNOS and eNOS, the rest cells were positive either for nNOS or for eNOS. CONCLUSION: The two constitutive nitric oxide synthases are distributed differently in the jejunum of rat. nNOS distributed in myenteric plexus is a neurotransmitter in the non-adrenergic non-cholinergic (NANC) inhibitory nerves. eNOS distributed in endothelial and smooth muscle cells of blood vessels plays vasodilator role. eNOS and nNOS are coexpressed in some cells of lamina propria of villi. NO generated by those NOS is very important in the physiological and pathological process of small intestine. 展开更多
关键词 Animals Immunohistochemistry JEJUNUM Male Nitric Oxide synthase Nitric Oxide synthase Type I Nitric Oxide synthase Type III RATs Rats sprague-Dawley Research support Non-U.s. Gov't Tissue distribution
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Leak Detection in Water Distribution Systems Using Bayesian Theory and Fisher’s Law 被引量:1
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作者 张宏伟 王丽娟 《Transactions of Tianjin University》 EI CAS 2011年第3期181-186,共6页
A leak detection method based on Bayesian theory and Fisher’s law was developed for water distribution systems. A hydraulic model was associated with the parameters of leaks (location, extent). The randomness of para... A leak detection method based on Bayesian theory and Fisher’s law was developed for water distribution systems. A hydraulic model was associated with the parameters of leaks (location, extent). The randomness of parameter values was quantified by probability density function and updated by Bayesian theory. Values of the parameters were estimated based on Fisher’s law. The amount of leaks was estimated by back propagation neural network. Based on flow characteristics in water distribution systems, the location of leaks can be estimated. The effectiveness of the proposed method was illustrated by simulated leak data of node pressure head and flow rate of pipelines in a test pipe network, and the leaks were spotted accurately and renovated on time. 展开更多
关键词 water distribution systems LEAK DETECTION EPANET Fisher's law Bayesian theory back propagationneural network
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Natural variations and geographical distributions of seed carotenoids and chlorophylls in 1167 Chinese soybean accessions 被引量:1
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作者 Berhane S.GEBREGZIABHER ZHANG Sheng-rui +7 位作者 Muhammad AZAM QI Jie Kwadwo G.AGYENIM-BOATENG FENG Yue LIU Yi-tian LI Jing LI Bin SUN Jun-ming 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第9期2632-2647,共16页
Understanding the composition and contents of carotenoids in various soybean seed accessions is important for their nutritional assessment.This study investigated the variability in the concentrations of carotenoids a... Understanding the composition and contents of carotenoids in various soybean seed accessions is important for their nutritional assessment.This study investigated the variability in the concentrations of carotenoids and chlorophylls and revealed their associations with other nutritional quality traits in a genetically diverse set of Chinese soybean accessions comprised of cultivars and landraces.Genotype,planting year,accession type,seed cotyledon color,and ecoregion of origin significantly influenced the accumulation of carotenoids and chlorophylls.The mean total carotenoid content was in the range of 8.15–14.72μg g–1 across the ecoregions.The total carotenoid content was 1.2-fold higher in the landraces than in the cultivars.Soybeans with green cotyledons had higher contents of carotenoids and chlorophylls than those with yellow cotyledons.Remarkably,lutein was the most abundant carotenoid in all the germplasms,ranging from 1.35–37.44μg g–1.Carotenoids and chlorophylls showed significant correlations with other quality traits,which will help to set breeding strategies for enhancing soybean carotenoids without affecting the other components.Collectively,our results demonstrate that carotenoids are adequately accumulated in soybean seeds,however,they are strongly influenced by genetic factors,accession type,and germplasm origin.We identified novel germplasms with the highest total carotenoid contents across the various ecoregions of China that could serve as the genetic materials for soybean carotenoid breeding programs,and thereby as the raw materials for food sectors,pharmaceuticals,and the cosmetic industry. 展开更多
关键词 accession type carotenoid CHLOROPHYLL ECOREGION geographical distribution Pearson’s correlation soybean(Glycine max L.Merrill)
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Acceptance Sampling Plans with Truncated Life Tests for the Length-Biased Weighted Lomax Distribution 被引量:1
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作者 Amer Ibrahim Al-Omari Ibrahim M.Almanjahie Olena Kravchuk 《Computers, Materials & Continua》 SCIE EI 2021年第4期285-301,共17页
In this paper,we considered the Length-biased weighted Lomax distribution and constructed new acceptance sampling plans(ASPs)where the life test is assumed to be truncated at a pre-assigned time.For the new suggested ... In this paper,we considered the Length-biased weighted Lomax distribution and constructed new acceptance sampling plans(ASPs)where the life test is assumed to be truncated at a pre-assigned time.For the new suggested ASPs,the tables of the minimum samples sizes needed to assert a specific mean life of the test units are obtained.In addition,the values of the corresponding operating characteristic function and the associated producer’s risks are calculated.Analyses of two real data sets are presented to investigate the applicability of the proposed acceptance sampling plans;one data set contains the first failure of 20 small electric carts,and the other data set contains the failure times of the air conditioning system of an airplane.Comparisons are made between the proposed acceptance sampling plans and some existing acceptance sampling plans considered in this study based on the minimum sample sizes.It is observed that the samples sizes based on the proposed acceptance sampling plans are less than their competitors considered in this study.The suggested acceptance sampling plans are recommended for practitioners in the field. 展开更多
关键词 Acceptance sampling plan producer’s risk truncated life tests operating characteristic function length-biased weighted lomax distribution consumer’s risk
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Improved Attribute Chain Sampling Plan for Darna Distribution 被引量:1
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作者 Harsh Tripathi Amer Ibrahim Al-Omari +1 位作者 Mahendra Saha Ayed R.A.Alanzi 《Computer Systems Science & Engineering》 SCIE EI 2021年第9期381-392,共12页
Recently,the Darna distribution has been introduced as a new lifetime distribution.The two-parameter Darna distribution represents is a mixture of two well-known gamma and exponential distributions.A manufacturer or a... Recently,the Darna distribution has been introduced as a new lifetime distribution.The two-parameter Darna distribution represents is a mixture of two well-known gamma and exponential distributions.A manufacturer or an engineer of products conducts life testing to examine whether the quality level of products meets the customer’s requirements,such as reliability or the minimum lifetime.In this article,an attribute modified chain sampling inspection plan based on the time truncated life test is proposed for items whose lifetime follows the Darna distribution.The plan parameters,including the sample size,the acceptance number,and the past lot result of the proposed sampling plan,are determined with the help of the two-point approach considering the acceptable quality level(AQL)and the limiting quality level(LQL).The plan parameters and the corresponding operating characteristic functions of a new plan are provided in tabular form for various Darna distribution parameters.Also,a few illustrated examples are presented for various distribution parameters.The usefulness of the proposed attribute modified chain sampling plan is investigated using two real failure time datasets.The results indicate that the proposed sampling plan can reduce the sample size when the termination ratio increases for fixed values of the producer’s risk and acceptance number.Hence,the proposed attribute modified chain sampling inspection plan is recommended to practitioners in the field. 展开更多
关键词 Attribute chain sampling inspection plan consumer’s risk Darna distribution operating characteristic curve producer’s risk truncated life test
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Comparison of the Bayesian Methods on Interval-Censored Data for Weibull Distribution 被引量:1
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作者 Al Omari Mohammed Ahmed 《Open Journal of Statistics》 2014年第8期570-577,共8页
This study considers the estimation of Maximum Likelihood Estimator and the Bayesian Estimator of the Weibull distribution with interval-censored data. The Bayesian estimation can’t be used to solve the parameters an... This study considers the estimation of Maximum Likelihood Estimator and the Bayesian Estimator of the Weibull distribution with interval-censored data. The Bayesian estimation can’t be used to solve the parameters analytically and therefore Markov Chain Monte Carlo is used, where the full conditional distribution for the scale and shape parameters are obtained via Metropolis-Hastings algorithm. Also Lindley’s approximation is used. The two methods are compared to maximum likelihood counterparts and the comparisons are made with respect to the mean square error (MSE) to determine the best for estimating of the scale and shape parameters. 展开更多
关键词 Weibull distribution BAYEsIAN Method INTERVAL Censored METROPOLIs-HAsTINGs Algorithm Lindley’s APPROXIMATION
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