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Gut microbiota-astrocyte axis: new insights into age-related cognitive decline
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作者 Lan Zhang Jingge Wei +5 位作者 Xilei Liu Dai Li Xiaoqi Pang Fanglian Chen Hailong Cao Ping Lei 《Neural Regeneration Research》 SCIE CAS 2025年第4期990-1008,共19页
With the rapidly aging human population,age-related cognitive decline and dementia are becoming increasingly prevalent worldwide.Aging is considered the main risk factor for cognitive decline and acts through alterati... With the rapidly aging human population,age-related cognitive decline and dementia are becoming increasingly prevalent worldwide.Aging is considered the main risk factor for cognitive decline and acts through alterations in the composition of the gut microbiota,microbial metabolites,and the functions of astrocytes.The microbiota–gut–brain axis has been the focus of multiple studies and is closely associated with cognitive function.This article provides a comprehensive review of the specific changes that occur in the composition of the gut microbiota and microbial metabolites in older individuals and discusses how the aging of astrocytes and reactive astrocytosis are closely related to age-related cognitive decline and neurodegenerative diseases.This article also summarizes the gut microbiota components that affect astrocyte function,mainly through the vagus nerve,immune responses,circadian rhythms,and microbial metabolites.Finally,this article summarizes the mechanism by which the gut microbiota–astrocyte axis plays a role in Alzheimer’s and Parkinson’s diseases.Our findings have revealed the critical role of the microbiota–astrocyte axis in age-related cognitive decline,aiding in a deeper understanding of potential gut microbiome-based adjuvant therapy strategies for this condition. 展开更多
关键词 age aging Alzheimer’s disease ASTROCYTES cognitive decline dementia gut microbiota gut–brain axis microbial metabolites NEUROINFLAMMATION Parkinson’s disease
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Revelation on the Drainage Systems of Ancient Villages in Jiangxi Province
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作者 刘丽 《Agricultural Science & Technology》 CAS 2016年第12期2855-2858,共4页
Based on rural drainage problems, the research analyzed traditional water culture in ancient vil ages in Jiangxi, as wel as flood control theory, and proposed specific theories and measures for drainage system improve... Based on rural drainage problems, the research analyzed traditional water culture in ancient vil ages in Jiangxi, as wel as flood control theory, and proposed specific theories and measures for drainage system improvement and construction in order to seek proper rural drainage system and promote rural sustainable develop-ment. 展开更多
关键词 Jiangxi Province Ancient vil ages Drainage
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Soil Organic Carbon Pool and Its Influencing Factors in Rubber Planted Forest Ecosystem at Different Ages in West Hainan Province 被引量:4
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作者 管利民 吴志祥 +2 位作者 杨川 谢贵水 周兆德 《Agricultural Science & Technology》 CAS 2012年第10期2163-2168,共6页
In this research,the contents of organic carbon in soil profiles in rubber forests in west of Hainan were measured and storage quantity of oganic carbon was estimated.The results indicated that contents of organic car... In this research,the contents of organic carbon in soil profiles in rubber forests in west of Hainan were measured and storage quantity of oganic carbon was estimated.The results indicated that contents of organic carbon in soils of ecosystem of rubber forests at different ages were 6.20-14.36 g/kg;organic carbon in soils of rubber forests reduced upon soil depth;the contents differed signigicantly in soils at 0-60 cm in rubber forest at 33 a,but differed little in soils in rubber forests at other ages;the contents were of significant differences in soils in rubber forests at different ages;organic carbon concentrated in soils at 0-30 cm;the storage quantities of organic carbon in rubber forests at 5,10,19 and 33 a were 76.85,74.48,81.74 and 85.31 t/hm^2.Climate,soil property,accumualtion and decomposition of fallen materials,forest age and management are dominant factors influencing accumulation of organic carbon in soils of rubber forest. 展开更多
关键词 Rubber planted forest Forestry age Soil organic carbon
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Effects of climate and forest age on the ecosystem carbon exchange of afforestation 被引量:8
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作者 Zhi Chen Guirui Yu Qiufeng Wang 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第2期365-374,共10页
Afforestation is believed to be an effective practice to reduce global warming by sequestering large amounts of carbon in plant biomass and soil.However,the factors that determine the rate of carbon sequestration with... Afforestation is believed to be an effective practice to reduce global warming by sequestering large amounts of carbon in plant biomass and soil.However,the factors that determine the rate of carbon sequestration with afforestation are still poorly understood.We analyzed ecosystem carbon exchange after afforestation based on eddy covariance measurements with the aim to identify factors responsible for the rate of carbon exchange following afforestation.The results indicated that afforestation in the tropical/subtropical and temperate climate zones had greater capacities for carbon sequestration than those in boreal zones.Net ecosystem production(NEP),gross primary production(GPP)and ecosystem respiration(RE)varied greatly with age groups over time.Specifically,NEP was initially less than zero in the\10 year group and then increased to its peak in the 10-20 year group.Afforestation of varied previous land use types and planting of diverse tree species did not result in different carbon fluxes.The general linear model showed that climate zone and age of afforestation were the dominant factors influencing carbon sequestration.These factors jointly controlled 51%,61%and 63%of the variation in NEP,GPP and RE,respectively.Compared to the strong regulation of climate on GPP and RE,NEP showed greater sensitivity to the age of afforestation.These results increase our understanding of the variation in ecosystem carbon exchange of afforestation and suggest that afforestation in subtropical and temperate areas after 20 years would yield greater carbon sink benefits than would afforestation of boreal regions. 展开更多
关键词 AFFORESTATION Carbon sequestration Eddy covariance CLIMATE Age
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The Early Hydration and Strength Development of High-strength Precast Concrete with Cement/Metakaolin Systems 被引量:10
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作者 曾俊杰 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2010年第4期712-716,共5页
To study the relationship between material composition, curing conditions and strength development, the study simulated high-strength precast concrete pile production, and a high-strength mortar up to 90 MPa was desig... To study the relationship between material composition, curing conditions and strength development, the study simulated high-strength precast concrete pile production, and a high-strength mortar up to 90 MPa was designed and a hot-water pool was built for concrete curing. The major point of the study was to achieve a high early strength by using cement/metakaolin systems without autoclave curing with high-pressure steam. By means of XRD and thermal analysis, the progress of the hydration of the cement pastes blended with metakaolin was characterized. The main results indicate that high strength can be obtained at early age by the use of metakaolin and thermal treatment (hot-water curing). The improvement in strength of mortars with metakaolin can be explained by an increase in the amount of C-S-H and C-S-A-H hydrated phases and a decrease in the amount of calcium hydration(CH). Further more, a decrease in Ca/Si ratio of the matrix was observed from the results of EDX analysis, which also leaded to an improvement of the compressive strength. These results are of great importance for the high-strength precast concrete manufacturing industry. 展开更多
关键词 METAKAOLIN early age hot-water curing hydration product
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Geochronology,Geochemistry,and Implications of Aplite Dyke in the Giant Jiama Porphyry Copper System,Tibet 被引量:5
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作者 QI Jing TANG Juxing +10 位作者 LIN Bin YANG Hairui TANG Xiaoqian TANG Pan FANG Xiang ZHANG Tingting LI Faqiao SUN Miao WANG Mengdie CUI Hao XIE Jinling 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第5期1406-1421,共16页
Jiama is a giant,high-grade porphyry copper system in the Gangdese metallogenic belt,Tibet.Multistage intermediate-felsic porphyries intruded in this deposit,some of which are strongly associated with copper-polymetal... Jiama is a giant,high-grade porphyry copper system in the Gangdese metallogenic belt,Tibet.Multistage intermediate-felsic porphyries intruded in this deposit,some of which are strongly associated with copper-polymetallic mineralization.These ore-bearing porphyries include monzogranite,granodiorite,and quartz diorite porphyries.A new granite aplite dyke was found in the south of Jiama.Its age,genesis,and relationship with ore-related magmatism are obscure.Here,its emplacement age and petrogenesis were determined using mineralogy,zircon U-Pb dating,geochemistry,and Sr-Nd-Pb isotope studies.The zircon LA-ICP-MS U-Pb age of the aplite dyke is 16.66±0.21 Ma(n=14,MSWD=0.66),earlier than that of the ore-bearing porphyries(~15 Ma)in Jiama.Furthermore,the aplite exhibits high amounts of silicon(SiO_(2)=73.39%-74.74%),potassium(K_(2)O=5.12%-6.61%),aluminum(Al_(2)O_(3)=14.25%-14.69%),and light/heavy rare earth elements(LREE/HREE=12.12-16.19)as well as negative europium(δEu=0.47-0.72)and weak negative cerium anomalies(δCe=0.84-0.93).The aplite dyke is characteristic of metaluminous-peraluminous I-type granite,which is rich in large-ion lithophile elements(Rb,Ba,Th and U)and depleted in high-field-strength elements(Nb,P and Ti).The aplite dyke and ore-bearing porphyries in the Jiama deposit are the results of a partial melting of the juvenile lower crust,according to whole-rock geochemistry and Sr-Nd-Pb isotope data,but the dyke and ore-bearing porphyries were emplaced from the same magma chamber at different times.Thus,the aplite dyke shows the composition of the early evolution stage of shallow magma in the Jiama deposit and is the product of rapid condensation and crystallization. 展开更多
关键词 U-Pb age Sr-Nd-Pb isotope GEOCHEMISTRY aplite dyke JIAMA
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Dynamics of ecosystem carbon stocks during vegetation restoration on the Loess Plateau of China 被引量:7
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作者 WANG Kaibo DENG Lei +3 位作者 REN Zongping SHI Weiyu CHEN Yiping SHANG-GUAN Zhouping 《Journal of Arid Land》 SCIE CSCD 2016年第2期207-220,共14页
In the last few decades, the Loess Plateau had experienced an extensive vegetation restoration to reduce soil erosion and to improve the degraded ecosystems. However, the dynamics of ecosystem carbon stocks with veget... In the last few decades, the Loess Plateau had experienced an extensive vegetation restoration to reduce soil erosion and to improve the degraded ecosystems. However, the dynamics of ecosystem carbon stocks with vegetation restoration in this region are poorly understood. This study examined the changes of carbon stocks in mineral soil (0-100 cm), plant biomass and the ecosystem (plant and soil) following vegetation restoration with different models and ages. Our results indicated that cultivated land returned to native vegetation (natural restoration) or artificial forest increased ecosystem carbon sequestration. Tree plantation sequestered more carbon than natural vegetation succession over decades scale due to the rapid increase in biomass carbon pool. Restoration ages had different effects on the dynamics of biomass and soil carbon stocks. Biomass carbon stocks increased with vegetation restoration age, while the dynamics of soil carbon stocks were affected by sampling depth. Ecosystem carbon stocks consistently increased after tree plantation regardless of the soil depth; but an initial decrease and then increase trend was observed in natural restoration chronosequences with the soil sampling depth of 0-100 cm. Moreover, there was a time lag of about 15-30 years between biomass production and soil carbon sequestration in 0-100 cm, which indicated a long-term effect of vegetation restoration on deeper soil carbon sequestration. 展开更多
关键词 AGES carbon stocks natural vegetation restoration tree plantation Loess Plateau
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Neurotherapeutic potential of erythropoietin after ischemic injury of the central nervous system 被引量:15
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作者 Florian Simon Nicolaos Floros +2 位作者 Wiebke Ibing Hubert Schelzig Artis Knapsis 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第8期1309-1312,共4页
Erythropoietin (EPO) is one of the most successful biopharmaceuticals in history and is used for treating anemia of different origins. However, it became clear that EPO could also work in a neuroprotective, antiapopto... Erythropoietin (EPO) is one of the most successful biopharmaceuticals in history and is used for treating anemia of different origins. However, it became clear that EPO could also work in a neuroprotective, antiapoptotic, antioxidative, angiogenetic and neurotropic way. It causes stimulation of cells to delay cell apoptosis, especially in the central nervous system. In rodent models of focal cerebral ischemia, EPO showed an impressive reduction of infarct size by 30% and improvement of neurobehavioral outcome by nearly 40%. A large animal model dealing with ischemia and reperfusion of the spinal cord showed that EPO could reduce the risk of spinal cord injury significantly. In addition, some clinical studies tested whether EPO works in real live clinical settings. One of the most promising studies showed the innocuousness and improvements in follow-up, outcome scales and in infarct size, of EPO-use in humans suffering from ischemic stroke. Another study ended unfortunately in a negative outcome and an increased overall death rate in the EPO group. The most possible reason was the involvement of patients undergoing simultaneously systemic thrombolysis with recombinant tissue plasminogen activator. An experimental study on rats demonstrated that administration of EPO might exacerbate tissue plasminogen activator-induced brain hemorrhage without reducing the ischemic brain damage. This case shows clearly how useful animal models can be to check negative side effects of a treatment before going into clinical trials. Other groups looked in human trials at the effects of EPO on the outcome after ischemic stroke, relation to circulating endothelial progerdtor cells, aneurysmal subarachnoid hemorrhage, traumatic brain injury, hemoglobin transfusion thresholds and elective first-time coronary artery bypass surgery. Most of the results were pos-让ive, but are based mostly on small group sizes. However, some of the most neglected facts when focusing on experimental setups of ischemia of the central nervous system are issues like age and comorbidities. It might be extremely worthy to consider these points for future projects, because EPO might influence all these factors. 展开更多
关键词 ERYTHROPOIETIN apoptosis central nervous system cerebral ISCHEMIA animal model stroke human trials age COMORBIDITY SPINAL CORD ISCHEMIA
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Isotope systematics and metallogenetic age of Zhuanghe gold deposit, Liaoning province, China 被引量:4
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作者 魏俊浩 谭文娟 +3 位作者 郭大招 谭俊 李闫华 鄢云飞 《Journal of Central South University of Technology》 EI 2007年第1期104-110,共7页
Based on the metallogenetic geology conditions, the H, O, C and S isotopic compositions were measured by MAT-251 mass spectrometer, and Pb isotope and Rb-Sr dating were carried with MAT-261 multi-acceptor mass spectro... Based on the metallogenetic geology conditions, the H, O, C and S isotopic compositions were measured by MAT-251 mass spectrometer, and Pb isotope and Rb-Sr dating were carried with MAT-261 multi-acceptor mass spectrometer. The results show that the δ^180 values of gold-bearing vein quartz from different levels are 1.19%-1.42%. The calculated δ^180 values of ore fluids are 0.55%-0.78%, and 319 values are from -8.64% to -6.66%. The calculated values of δ^34SH2s by the δ^34Spy values in quartz veins display sulfur isotope compositions from -0.053% to +0.413%. Carbon isotope compositions of carbonates are from -0.612% to 0.140%. The mole ratios of ^206Pb to ^204Pb, ^207Pb to ^204Pb and ^208Pb to ^204Pb in auriferous quartz vein are 16.987-17.545, 15.342-15.623, and 38.254-38.744, respectively. The age of the Zhuanghe gold deposit determined by Rb-Sr isochron of the fluid inclusions in quartzes is (143.0±5.8) Ma. These isotopic data suggest that the metallogenetic fluids are generated from magmatic hydrotherm and the origin of ore-forming matters is related to the deep-derived magmatic activities. Meanwhile, the metallogenetic epoch of the Zhuanghe gold deposit is in Yanshanian period. 展开更多
关键词 isotope systematics metallogenetic age Zhuanghe gold deposit
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National Nutrition and Health Systematic Survey for Children 0–17 Years of Age in China 被引量:5
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作者 YANG Zhen Yu ZHANG Qian +13 位作者 ZHAI Yi XU Tao WANG Yu Ying CHEN Bo Wen TANG Xue Jun YUAN Xiao Lin FANG Hong Yun ZHU Yan PANG Xue Hong WANG Shuo XU Juan LI Rui Li SI Xiang ZHAO Wen Hua 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2021年第11期891-899,共9页
The main purpose of the National Nutrition and Health Systematic Survey for children 0-17 years of age in China(CNHSC)was to collect basic data on the nutrition,development,and health status for children in different ... The main purpose of the National Nutrition and Health Systematic Survey for children 0-17 years of age in China(CNHSC)was to collect basic data on the nutrition,development,and health status for children in different regions across China using evidence-based,reliable,and cost-effective approaches.Children and their parents or guardians from seven regions(south,southwest,north,northwest,eastern,central,and northeast China)in China were recruited.A multi-stage stratified randomized sampling method was used.Two provinces were randomly sampled from each of the seven regions,from which one urban district and one rural country were also randomly sampled,resulting in a total of 28 survey counties/districts.Dietary surveys,health examinations,laboratory testing,and questionnaires were used to collect dietary intake,nutritional status,child development,and health status information.Nutrition,health,and lifestyle assessment of children and their parents was determined using the Knowledge Attitude Practice(KAP)survey.Greater than 100,000 children(38,000 children<6 years of age and 66,000 children6-17 years of age)completed the survey.The survey provided comprehensive data on child nutrition and health status for future studies and will serve as the basis for an integrated nutrition and health improvement strategies proposal for children in China. 展开更多
关键词 Children 0-17 years of age Nutritional status Health status Study protocol
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Modeling of residual chlorine in water distribution system 被引量:4
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作者 LIXin M.Ukita 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2003年第1期136-144,共9页
Water quality within water distribution system may vary with both location and time. Water quality models are used to predict the spatial and temporal variation of water quality throughout water system. A model of res... Water quality within water distribution system may vary with both location and time. Water quality models are used to predict the spatial and temporal variation of water quality throughout water system. A model of residual chlorine decay in water pipe has been developed, given the consumption of chlorine in reactions with chemicals in bulk water, bio films on pipe wall, in corrosion process, and the mass transport of chlorine from bulk water to pipe wall. Analytical methods of the flow path from water sources to the observed point and the water age of every observed node were proposed. Model is used to predict the decay of residual chlorine in an actual distribution system. Good agreement between calculated and measured values was obtained. 展开更多
关键词 residual chlorine bulk water CORROSION bio film water quality water distribution system flow path water age
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Demand analysis of an intelligent medication administration system for older adults with chronic diseases based on the Kano model 被引量:6
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作者 Jiayi Mao Liling Xie +4 位作者 Qinghua Zhao Mingzhao Xiao Shuting Tu Wenjing Sun Tingting Zhou 《International Journal of Nursing Sciences》 CSCD 2022年第1期63-70,I0004,共9页
Objectives Gerontechnology has great potential in promoting older adults’well-being.With the accelerated aging process,gerontechnology has a promising market prospect.However,most technological developers and healthc... Objectives Gerontechnology has great potential in promoting older adults’well-being.With the accelerated aging process,gerontechnology has a promising market prospect.However,most technological developers and healthcare professionals attached importance to products’effectiveness,and ignored older adults’demands and user experience,which reduced older adults'adoption intention of gerontechnology use.The inclusion of older adults in the design process of technologies is essential to maximize the effect.This study explored older adults’demands for a self-developed intelligent medication administration system and proposed optimization schemes,thus providing reference to developing geriatric-friendly technologies and products.Methods A cross-sectional survey was conducted to explore older adults’technological demands for the self-developed intelligent medication administration system,and data were analyzed based on the Kano model.A self-made questionnaire was administered from July 2020 to October 2020 after participants used this system for two weeks.The study was registered with the Chinese Clinical Trial Registry(ChiCTR2000040644).Results A total of 354 older adults participated in the survey.Four items,namely larger font size,simpler operation process,scheduled medication reminders and reliable hardware,were classified as must-be attributes;three items,namely searching drug instructions through WeChat,more sensitive system and longer battery life,as attractive attributes;one item,viewing disease-related information through WeChat,as the one-dimensional attribute;and the rest were indifferent attributes,including simple and beautiful displays,blocking advertisements automatically,providing user privacy protection protocol,viewing personal medical information only by logged-in users,recording all the medications,ordering medications through WeChat.The satisfaction values were between 0.24 and 0.69,and dissatisfaction values were between 0.06 and 0.94.Conclusion This study suggested that older adults had personalized technology demands.Including their technological demands and desire may assist in decreasing the digital divide and promoting the satisfaction of e-health and/or m-health.Based on older adults’demands,our study proposed optimization schemes of the intelligent medication administration system,which may help developers design geriatric-friendly intelligent products and nurses to perform older adults-centered and efficient medication management. 展开更多
关键词 Aged COMMUNICATION Data collection Electronic medication device Medication therapy management Mobile applications Needs assessment Personal satisfaction
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Effect of age on click-evoked otoacoustic emission A systematic review 被引量:2
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作者 Jinfeng Liu Ningyu Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第11期853-861,共9页
OBJECTIVE:The aims of this study were to investigate the changes of the total intensity of transient evoked otoacoustic emission(TEOAE) and signal-to-noise ratio in various frequency bands as a function of aging,an... OBJECTIVE:The aims of this study were to investigate the changes of the total intensity of transient evoked otoacoustic emission(TEOAE) and signal-to-noise ratio in various frequency bands as a function of aging,and to explore the role of age-related decline of cochlear outer hair cells.DATA SOURCES:The literature was searched using the PubMed database using 'transient-evoked otoacoustic emissions' as a keyword.Articles were limited as follows:Species was 'Humans';languages were 'English and Chinese';publication date between 1990-01-01 and 2010-12-31.The references of the found were also searched to obtain additional articles.DATA SELECTION:Inclusion criteria:(1) Articles should involve the total TEOAE level or signal-to-noise ratio.(2) The measurement and analysis system used was Otodynamics ILO analysis system(ILO88,ILO92,ILO96 or ILO292).(3) Studies involved groups of greater than 10 subjects and TEOAE results were from normally hearing ears.(4) If more papers from the same author or laboratory analyzed the same subjects,only one was used.MAIN OUTCOME MEASURES:The correlations of the age scale with the total level and signal-to-noise ratio of TEOAE was determined,respectively.RESULTS:(1) TEOAE total level gradually increased until 2 months of age,and then decreased with increasing age.Significant negative correlations between total TEOAE level and age were found(r =-0.885,P = 0.000).(2) The most rapid decrease of TEOAE amplitude occurred at 1 year old.The total TEOAE level decreased about 4.25 dB SPL between 2 months to 1 year old,then about 0.26-0.52 dB SPL from 1 year to 10 years old,about 0.23 dB SPL from 11 years to 25 years old,and about 0.14 dB SPL from 26 years to 60 years old.(3) The signal-to-noise ratio in the frequency bands centered at 1.5,2,3 and 4 kHz decreased with increasing age after 2 months of age.Significant negative correlations between the signal-to-noise ratio and age were found for frequency bands ranging from 1.5 kHz to 4 kHz,with the highest correlations at 4 kHz(r =-0.890,P 〈 0.01),then at 3 kHz(r =-0.889,P 〈 0.01),at 2 kHz(r =-0.850,P 〈 0.01) and at 1.5 kHz(r =-0.705,P 〈 0.05).Conversely,a positive correlation between the signal-to-noise ratio centered at 1 kHz and age was found,but was not statistically significant(r = 0.298,P = 0.374).CONCLUSION:The total TEOAE response level decreased with increasing age after the first 2 months of age.The signal-to-noise ratio also decreased with increasing age in frequency bands above 1.5 kHz.The signal-to-noise ratio in higher frequencies decreased faster than in lower frequencies,leading to the maximum signal-to-noise ratio shift form 3.2-4.0 kHz in neonates to 1.5 kHz in adults,and further decreasing the total TEOAE response level.The age-related TEOAE spectrum peak shift is most likely because the outer hair cells functioning in higher frequencies are more prone to damage than those for lower frequencies. 展开更多
关键词 age transient-evoked otoacoustic emission signal-to-noise ratio outer hair cells META-ANALYSIS
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Effect of Lamb Age and in vitro Culture System of Oocytes on JIVET Technology 被引量:3
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作者 Yangyi MAO Huidi LUO +7 位作者 Guanwu ZHANG Zhiwu WANG Peng ZHAO Jun LI Hongyu GUO Shenghua ZHOU Huihui GUO Chunyan LI 《Agricultural Biotechnology》 CAS 2019年第1期86-89,92,共5页
[Objectives] This study was conducted to investigate the effects of lamb age and in vitro culture system of oocytes on the results of juvenile in vitro embryo transfer( JIVET). [Methods]Ten Dorper × small-tailed ... [Objectives] This study was conducted to investigate the effects of lamb age and in vitro culture system of oocytes on the results of juvenile in vitro embryo transfer( JIVET). [Methods]Ten Dorper × small-tailed Han lambs aged 5 to 10 weeks were induced to superovulate via i. p. injection of pregnant mare's serum gonadotropin( PMSG). The oocytes were matured in basal maturation solution or modified maturation solution,which was prepared by adding 200 μmol/L cysteine to the basal maturation solution. Then,the oocytes were fertilized in fertilization medium I containing 2% estrus sheep serum( ESS) or fertilization medium II containing 3 mg/ml bull serum albumin( BSA). Finally,the number of oocytes,oocyte maturation rate and cleavage rate of the lambs of different ages were determined. [Results]The average number of oocytes recovered per lamb was( 111. 00 ± 16. 97),( 139. 50 ± 28. 99),( 108. 50 ± 17. 68) and( 42. 00 ± 11. 31) for5-,7-,8-and 10-week-old Dorper × small-tailed Han lambs,respectively. The number of oocytes obtained from 5-,7-and 8-week-old lambs was significantly higher than that from 10-week-old lambs( P < 0. 05),but there was no significant difference among 5-,7-and 8-week-old lambs( P > 0. 05). The maturation rate of oocytes cultured in modified maturation solution was 3. 64% higher than that in basal maturation solution. The cleavage rate of oocytes in fertilization medium I was very significantly higher than that in fertilization medium II( P < 0. 01). [Conclusions] The results of JIVET can be improved by harvesting oocytes from lambs aged 5-8 weeks,adding a certain amount of cysteine into oocyte maturation solution,and a certain amount of ESS into fertilization medium. 展开更多
关键词 JUVENILE LAMBS Age OOCYTES In VITRO culture system JIVET Maturation RATE Cleavage RATE
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U–Pb zircon age of the base of the Ediacaran System at the southern margin of the Qinling Orogen 被引量:1
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作者 Lecai Xing Taiyi Luo +3 位作者 Zhilong Huang Zhikuan Qian Mingzhong Zhou Hongtao He 《Acta Geochimica》 EI CAS CSCD 2018年第3期414-421,共8页
Global abrupt climate change from Marinoan snowball Earth to greenhouse Earth, recorded as cap carbonate overlain on diamictite, had shed the first light on Cambrian bio-radiation. The most documented cap carbonate se... Global abrupt climate change from Marinoan snowball Earth to greenhouse Earth, recorded as cap carbonate overlain on diamictite, had shed the first light on Cambrian bio-radiation. The most documented cap carbonate sections are typical with comprehensive d13 C negative values and ubiquitous sedimentary structures, such as tepee-like, sheet-crack etc., which are associated with successive glacial eustatic variation caused by isostatic rebound in shallow-water facies. Here we report a deepwater basinal cap carbonate section with strong negative δ^(13) C values in the southern margin of the Qinling Orogen,Heyu, Chengkou County, Chongqing in China, which consists of massive dolostone with abundant carbonaceous laminae. However, it lacks the sedimentary structure as mentioned above and is overlain by thin-bedded silicious shales and cherts. A K-bentonite bed was discovered within the base of cap carbonates, about 0.7 m above the top of the Marinoan diamictite. Magmatic zircons that were separated from the K-bentonite bed yield a SIMS concordia U–Pb age of 634.1 ± 1.9 Ma(1 r, MSWDCE= 0.31,ProbabilityCE= 1.000, n = 20). The age is in good agreement with previously reported TIMS U–Pb ages for the termination of Marinoan glaciation and provides ageochronological constraint for the Ediacaran successions in the Qinling Orogen. 展开更多
关键词 NEOPROTEROZOIC Cap DOLOSTONE K-BENTONITE U-Pb age QINLING OROGEN
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Assessment on reliability of water quality in water distribution systems 被引量:1
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作者 伍悦滨 田海 王龙岩 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第5期481-484,共4页
Water leaving the treatment works is usually of a high quality but its properties change during the transportation stage. Increasing awareness of the quality of the service provided within the water industry today and... Water leaving the treatment works is usually of a high quality but its properties change during the transportation stage. Increasing awareness of the quality of the service provided within the water industry today and assessing the reliability of the water quality in a distribution system has become a major significance for decision on system operation based on water quality in distribution networks. Using together a water age model, a chlorine decay model and a model of acceptable maximum water age can assess the reliability of the water quality in a distribution system. First, the nodal water age values in a certain complex distribution system can be calculated by the water age model. Then, the acceptable maximum water age value in the distribution system is obtained based on the chlorine decay model. The nodes at which the water age values are below the maximum value are regarded as reliable nodes. Finally, the reliability index on the percentile weighted by the nodal demands reflects the reliability of the water quality in the distribution system. The approach has been applied in a real water distribution network. The contour plot based on the water age values determines a surface of the reliability of the water quality. At any time, this surface is used to locate high water age but poor reliability areas, which identify parts of the network that may be of poor water quality. As a result, the contour water age provides a valuable aid for a straight insight into the water quality in the distribution system. 展开更多
关键词 reliability of water quality reliability index maximum water age contour water age water distribution systems
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Timely Updates in MEC-Assisted Status Update Systems: Joint Task Generation and Computation Offloading Scheme 被引量:3
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作者 Long Liu Xiaoqi Qin +1 位作者 Yunzheng Tao Zhi Zhang 《China Communications》 SCIE CSCD 2020年第8期168-186,共19页
Fresh status updates are vital to the efficient operation of network monitoring and real-time control applications. In this paper, we consider a mobile edge computing(MEC)-assisted status update system, where smart de... Fresh status updates are vital to the efficient operation of network monitoring and real-time control applications. In this paper, we consider a mobile edge computing(MEC)-assisted status update system, where smart devices extract valuable status updates from sensed data to achieve timely awareness of the surroundings by exploiting computational resources at the device and edge server. To quantify the freshness of status updates obtained by executing computation tasks, we employ the concept of age of information(Ao I) to characterize the timeliness of status updates. To cope with the limited energy at devices, we investigate a joint task generation and computation offloading scheme under a given energy budget for minimizing the age of obtained status updates. The age minimization problem is modeled as a constrained Markov decision process(CMDP). To obtain the optimal policy, we derive the structural properties of the optimal deterministic policy and propose a lightweight structure-based status update algorithm in the case of known channel statistics. Moreover, we consider a more realistic scenario without prior knowledge of channel statistics, and propose a Q-learning-based status update algorithm to make online decisions. Simulation results show that the performance of our proposed algorithms is competitive when compared with existing schemes. 展开更多
关键词 mobile edge computing age of information constrained Markov decision process structural analysis Q-LEARNING
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Autoimmune hepatitis treatment in the elderly: A systematic review 被引量:1
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作者 Marilena Durazzo Giulia Lupi +2 位作者 Michela ScANDella Arianna Ferro Gabriella Gruden 《World Journal of Gastroenterology》 SCIE CAS 2019年第22期2809-2818,共10页
BACKGROUND Autoimmune hepatitis (AIH) is a rare chronic inflammatory liver disease with a high risk of progression to liver cirrhosis. The initial treatment for AIH usually includes a steroid, with or without azathiop... BACKGROUND Autoimmune hepatitis (AIH) is a rare chronic inflammatory liver disease with a high risk of progression to liver cirrhosis. The initial treatment for AIH usually includes a steroid, with or without azathioprine. AIH can present at any age;however, the most effective and safe induction treatment for AIH in the elderly remains unclear. AIM To systematically review available data on both effectiveness and safety of AIH treatments in elderly subjects. METHODS To identify studies on AIH induction treatment in elderly patients (≥ 60 years of age), an electronic research was performed (PubMed, EMBASE and Cochrane Library databases) until February 2019. Eligible studies were selected through screening of titles and abstracts, followed by full-text critical evaluation. After risk of bias assessment, data on study designs, interventions, and outcomes were extracted and reviewed. RESULTS Among the 1736 retrieved papers, 15 studies were selected. Out of them, eight studies were excluded because of a critical risk of bias. The remaining seven studies included 789 patients and out of them 239 subjects were elders. First-line treatment was a steroid either alone or in combination with azathioprine in most patients (87.6%) and only one study investigated the effect of combined steroid and mycophenolate mofetil therapy. Standard therapy was effective in inducing remission in the elderly. Moreover, treatment failure and relapses occurred less often in the elderly compared to younger people.CONCLUSION Treatment of AIH is challenging in elderly patients. This systematic review confirms the efficacy and safety of standard induction treatment for AIH in the elderly. Available evidence is insufficient to draw any conclusion on the effect of novel AIH treatments in elderly subjects. 展开更多
关键词 AUTOIMMUNE hepatitis Elderly patients Aged STEROIDS AZATHIOPRINE MYCOPHENOLATE mofetil
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Assisted Hatching in Couples with Advanced Maternal Age: A Systematic Review and Meta-analysis 被引量:2
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作者 Fan HE Chan-yu ZHANG +2 位作者 Li-si WANG Sang-lin LI Li-na HU 《Current Medical Science》 SCIE CAS 2018年第3期552-557,共6页
This systematic review aimed to evaluate the efficacy and safety of assisted hatching (AH) performed in couples with advanced maternal age. We searched for randomized controlled trials (RCTs) in electronic databas... This systematic review aimed to evaluate the efficacy and safety of assisted hatching (AH) performed in couples with advanced maternal age. We searched for randomized controlled trials (RCTs) in electronic databases, including MEDLINE, EMBASE and CENTRAL (from inception to January 2018); in addition, we hand-searched the reference lists of included studies and similar reviews. We included RCTs comparing AH versus no treatment (control). The meta-analysis was performed by RevMan 5.3 software. The search retrieved 943 records and 8 RCTs were included, comprising 870 cycles (n=440 for AH, and n=430 for control). There was no significant difference in the rates of live birth (RR 0.88, 95% CI 0.65 to 1.18, 3 RCTs, n-427,I^2=0%), clinical pregnancy (RR 1.00, 95% CI 0.83 to 1.19, 8 RCTs, n=870, I^2=22%), implantation (RR 1.07, 95% CI 0.83 to 1.39, 4 RCTs, n=1359, I^2=0%), miscarriage (RR 1.13, 95% CI 0.66 to 1.94, 2 RCTs, n=116, I^2=0%) and multiple pregnancy (RR 0.89, 95% CI 0.31 to 2.52, 1 RCT, n=97,I^2=not applicable) between the treatment group and control group. No reasonable conclusions could be drawn regarding reproductive outcomes after AH in patients with advanced maternal age due to the small sample pooled in meta-analyses. Studies of high methodological quality and with adequate power are necessary to further investigate the value of AH in assisted conception of those patients. 展开更多
关键词 assisted hatching advanced maternal age in vitro fertilization frozen-thawed embryo transfer
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TECA hybrid artificial liver support system in treatment of acute liver failure 被引量:16
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作者 Yi-Long Xue~1 Shi-Feng Zhao~1 Yun-Luo~1 Xin-Jian Li~1 Zhong-Ping Duan~2 Xiao-Ping Chen~1 Wen-Ge Li~1 Xiao-Qiang Huang~1 Yan-Ling Li~1 Xin-Cui~1 Da-Guang Zhong~1 Zuo-Yun Zhang~1 Zhi-Qiang Huang~1 1 Chinese PLA General Hospital,Beijing 100853,China2 Beijing You-An Hospital,Beijing 100054,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第6期826-829,共4页
AIM: To assess the efficacy and safety of TECA type hybrid artificial liver support system (TECA-HALSS) in providing liver function of detoxification, metabolism and physiology by treating the patients with acute live... AIM: To assess the efficacy and safety of TECA type hybrid artificial liver support system (TECA-HALSS) in providing liver function of detoxification, metabolism and physiology by treating the patients with acute liver failure (ALF). METHODS: The porcine liver cells (1-2) x 10(10) were separated from the Chinese small swine and cultured in the bioreactor of TECA-BALSS at 37.0 degrees C and circulated through the outer space of the hollow fiber tubes in BALSS. The six liver failure patients with various degree of hepatic coma were treated by TECA-HALSS and with conventional medicines. The venous plasma of the patients was separated by a plasma separator and treated by charcoal adsorbent or plasma exchange. The plasma circulated through the inner space of the hollow fiber tubes of BALSS and mixed with the patients' blood cells and flew back to their blood circulation. Some small molecular weight substances were exchanged between the plasma and porcine liver cells. Each treatment lasted 6.0-7.0 h. Physiological and biochemical parameters were measured before,during and after the treatment. RESULTS: The average of porcine liver cells was (1.0-3.0) x 10(10) obtained from each swine liver using our modified enzymatic digestion method. The survival rate of the cells was 85%-93% by trypan blue stain and AO/PI fluorescent stain. After cultured in TECA-BALSS bioreactor for 6 h, the survival rate of cells still remained 70%-85%. At the end of TECA-HALSS treatment, the levels of plasma NH(3), ALT, TB and DB were significantly decreased. The patients who were in the state of drowsiness or coma before the treatment improved their appetite significantly and regained consciousness, some patients resumed light physical work on a short period after the treatment.One to two days after the treatment, the ratio of PTA increased warkedly. During the treatment, the heart rates, blood pressure, respiration condition and serum electrolytes (K(+), Na(+) and Cl(-)) were stable without thrombosis and bleeding in all the six patients. CONCLUSION: TECA-HALSS treatment could be a rapid, safe and efficacious method to provide temporary liver support for patients with ALF. 展开更多
关键词 Liver Artificial Acute Disease ADULT ANIMALS FEMALE Humans LIVER Liver Failure Male Middle Aged Research Support Non-U.S. Gov't SWINE Swine Miniature
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