期刊文献+
共找到341篇文章
< 1 2 18 >
每页显示 20 50 100
Maresin 1 alleviates neuroinflammation and cognitive decline in a mouse model of cecal ligation and puncture
1
作者 LI Longyan XING Manyu +1 位作者 WANG Lu ZHAO Yixia 《中南大学学报(医学版)》 CAS CSCD 北大核心 2024年第6期890-902,共13页
Objective:Inflammation in the central nervous system plays a crucial role in the occurrence and development of sepsis-associated encephalopathy.This study aims to explore the effects of maresin 1(MaR1),an anti-inflamm... Objective:Inflammation in the central nervous system plays a crucial role in the occurrence and development of sepsis-associated encephalopathy.This study aims to explore the effects of maresin 1(MaR1),an anti-inflammatory and pro-resolving lipid mediator,on sepsis-induced neuroinflammation and cognitive impairment.Methods:Mice were randomly assigned to 4 groups:A sham group(sham operation+vehicle),a cecal ligation and puncture(CLP)group(CLP operation+vehicle),a MaR1-LD group(CLP operation+1 ng MaR1),and a MaR1-HD group(CLP operation+10 ng MaR1).MaR1 or vehicle was intraperitoneally administered starting 1 h before CLP operation,then every other day for 7 days.Survival rates were monitored,and serum inflammatory cytokines[tumor necrosis factor alpha(TNF-α),interleukin(IL)-1β,and IL-6]were measured 24 h after operation using enzyme-linked immunosorbent assay(ELISA).Cognitive function was assessed 7 days after operation using the Morris water maze(MWM)test and novel object recognition(NOR)task.The mRNA expression of TNF-α,IL-1β,IL-6,inducible nitric oxide synthase(iNOS),IL-4,IL-10,and arginase 1(Arg1)in cortical and hippocampal tissues was determined by real-time reverse transcription PCR(RT-PCR).Western blotting was used to determine the protein expression of iNOS,Arg1,signal transducer and activator of transcription 6(STAT6),peroxisome proliferator-activated receptor gamma(PPARγ),and phosphorylated STAT6(p-STAT6)in hippocampal tissue.Microglia activation was visualized via immunofluorescence.Mice were also treated with the PPARγantagonist GW9662 to confirm the involvement of this pathway in MaR1’s effects.Results:CLP increased serum levels of TNF-α,IL-1β,and IL-6,and reduced body weight and survival rates(all P<0.05).Both 1 ng and 10 ng doses of MaR1 significantly reduced serum TNF-α,IL-1β,and IL-6 levels,improved body weight,and increased survival rates(all P<0.05).No significant difference in efficacy was observed between the 2 doses(all P>0.05).MWM test and NOR task indicated that CLP impaired spatial learning,which MaR1 mitigated.However,GW9662 partially reversed MaR1’s protective effects.Real-time RTPCR results demonstrated that,compared to the sham group,mRNA expression of TNF-α,IL-1β,and iNOS significantly increased in hippocampal tissues following CLP(all P<0.05),while IL-4,IL-10,and Arg1 showed a slight decrease,though the differences were not statistically significant(all P>0.05).Compared to the CLP group,both 1 ng and 10 ng MaR1 decreased TNF-α,IL-1β,and iNOS mRNA expression in hippocampal tissues and increased IL-4,IL-10,and Arg1 mRNA expression(all P<0.05).Immunofluorescence results indicated a significant increase in Iba1-positive microglia in the hippocampus after CLP compared to the sham group(P<0.05).Administration of 1 ng and 10 ng MaR1 reduced the percentage area of Iba1-positive cells in the hippocampus compared to the CLP group(both P<0.05).Western blotting results showed that,compared to the CLP group,both 1 ng and 10 ng MaR1 down-regulated the iNOS expression,while up-regulated the expression of Arg1,PPARγ,and p-STAT6(all P<0.05).However,the inclusion of GW9662 counteracted the MaR1-induced upregulation of Arg1 and PPARγcompared to the MaR1-LD group(all P<0.05).Conclusion:MaR1 inhibits the classical activation of hippocampal microglia,promotes alternative activation,reduces sepsis-induced neuroinflammation,and improves cognitive decline. 展开更多
关键词 SEPSIS cognitive decline maresin 1 MICROGLIA NEUROINFLAMMATION
下载PDF
Gut microbiota-astrocyte axis: new insights into age-related cognitive decline
2
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
下载PDF
Reasons and effects of the decline of willing related potential living kidney donors 被引量:1
3
作者 Rabea Ahmed Gadelkareem Amr Mostafa Abdelgawad +5 位作者 Nasreldin Mohammed Ahmed Reda Nashwa Mostafa Azoz Mohammed Ali Zarzour Hisham Mokhtar Hammouda Mahmoud Khalil 《World Journal of Transplantation》 2023年第5期276-289,共14页
BACKGROUND Although the availability of related living donors(LDs)provides a better chance for receiving kidney transplantation(KT),the evaluation protocols for LD selection remain a safeguard for the LD’s safety.The... BACKGROUND Although the availability of related living donors(LDs)provides a better chance for receiving kidney transplantation(KT),the evaluation protocols for LD selection remain a safeguard for the LD’s safety.These protocols are variable from one center to another,resulting in variable rates of decline of the potential LDs(PLDs).The decline of willing PLDs may occur at any stage of evaluation,starting from the initial contact and counseling to the day of operation.AIM To identify the causes of the decline of PLDs,the predictors of PLD candidacy,and the effect on achieving LDKT.METHODS A retrospective study was performed on the willing PLDs who attended our outpatient clinic for kidney donation to their related potential recipients between October 2015 and December 2022.The variables influencing their candidacy rate and the fate of their potential recipients were studied.Two groups of PLDs were compared:Candidate PLDs after a completed evaluation vs non-candidate PLDs with a complete or incomplete evaluation.A multivariate logistic regression was performed to assess the factors contributing to the achievement of PLD candidacy.RESULTS Of 321 willing PLDs,257 PLDs(80.1%)accessed the evaluation to variable extents for 212 potential recipients,with a mean age(range)of 40.5±10.4(18-65)years,including 169 females(65.8%).The remaining 64 PLDs(19.9%)did not access the evaluation.Only 58 PLDs(18.1%)succeeded in donating,but 199 PDLs(62.0%)were declined;exclusion occurred in 144 PLDs(56.0%)for immunological causes(37.5%),medical causes(54.9%),combined causes(9.7%),and financial causes(2.1%).Regression and release occurred in 55 PLDs(17.1%).The potential recipients with candidate PLDs were not significantly different from those with non-candidate PLDs,except in age(P=0.041),rates of completed evaluation,and exclusion of PLDs(P<0.001).There were no factors that independently influenced the rate of PLD candidacy.Most patients who failed to have KT after the decline of their PLDs remained on hemodialysis for 6 mo to 6 years.CONCLUSION The rate of decline of willing related PLDs was high due to medical or immunological contraindications,release,or regression of PLDs.It reduced the chances of high percentages of potential recipients in LDKT. 展开更多
关键词 Donor decline Donor evaluation Donor exclusion Kidney transplantation Living kidney donors Related living donors
下载PDF
Association between Serum Uric Acid and the Early Marker of Kidney Function Decline among Chinese Middle-Aged and Older Population:Evidence from the China Health and Retirement Longitudinal Study
4
作者 TANG Xu XU Lu +4 位作者 MENG Ruo Gu DU Yi Qing LIU Shi Jun ZHAN Si Yan XU Tao 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2023年第3期231-240,共10页
Objective To evaluate the association between serum uric acid(SUA)and kidney function decline.Methods Data was obtained from the China Health and Retirement Longitudinal Study on the Chinese middle-aged and older popu... Objective To evaluate the association between serum uric acid(SUA)and kidney function decline.Methods Data was obtained from the China Health and Retirement Longitudinal Study on the Chinese middle-aged and older population for analysis.The kidney function decline was defined as an annual estimated glomerular filtration rate(e GFR)decrease by>3 mL/min per 1.73 m^(2).Multivariable logistic regression was applied to determine the association between SUA and kidney function decline.The shape of the association was investigated by restricted cubic splines.Results A total of 7,346 participants were included,of which 1,004 individuals(13.67%)developed kidney function decline during the follow-up of 4 years.A significant dose-response relation was recorded between SUA and the kidney function decline(OR 1.14,95%CI 1.03-1.27),as the risk of kidney function decline increased by 14%per 1 mg/d L increase in SUA.In the subgroup analyses,such a relation was only recorded among women(OR 1.22,95%CI 1.03-1.45),those aged<60 years(OR 1.22,95%CI 1.05-1.42),and those without hypertension and without diabetes(OR 1.22,95%CI 1.06-1.41).Although the dose-response relation was not observed in men,the high level of SUA was related to kidney function decline(OR 1.83,95%CI 1.05-3.17).The restricted cubic spline analysis indicated that SUA>5 mg/dL was associated with a significantly higher risk of kidney function decline.Conclusion The SUA level was associated with kidney function decline.An elevation of SUA should therefore be addressed to prevent possible kidney impairment and dysfunction. 展开更多
关键词 Uric acid Glomerular filtration rate Kidney function decline
下载PDF
Diabetes and cognitive decline:Challenges and future direction
5
作者 Norhamidar Ab-Hamid Norsuhana Omar +1 位作者 Che Aishah Nazariah Ismail Idris Long 《World Journal of Diabetes》 SCIE 2023年第6期795-807,共13页
There is growing evidence that diabetes can induce cognitive decline and dementia.It is a slow,progressive cognitive decline that can occur in any age group,but is seen more frequently in older individuals.Symptoms re... There is growing evidence that diabetes can induce cognitive decline and dementia.It is a slow,progressive cognitive decline that can occur in any age group,but is seen more frequently in older individuals.Symptoms related to cognitive decline are worsened by chronic metabolic syndrome.Animal models are frequently utilized to elucidate the mechanisms of cognitive decline in diabetes and to assess potential drugs for therapy and prevention.This review addresses the common factors and pathophysiology involved in diabetes-related cognitive decline and outlines the various animal models used to study this condition. 展开更多
关键词 Diabetes mellitus Insulin signaling Macrovascular disease Microvascular disease Animal models Cognitive decline PATHOPHYSIOLOGY
下载PDF
Heterosis of Vine Decline Disease Resistance Caused by the Fungus Monosporascus cannonballus in Melons (Cucumis melo L)
6
作者 Sixto Alberto Marquez John Jifon +2 位作者 Kevin Michael Crosby Carlos Augusto Avila Amir Mohamed Hussein Ibrahim 《Agricultural Sciences》 CAS 2023年第5期629-635,共7页
Vine decline disease (VDD) constitutes a menace to melons worldwide. Especially, the one caused by the fungus Monosporascus cannonballus. Thus, resistant plant material must be released to help growers. Hence, our goa... Vine decline disease (VDD) constitutes a menace to melons worldwide. Especially, the one caused by the fungus Monosporascus cannonballus. Thus, resistant plant material must be released to help growers. Hence, our goal was to develop resistant plant material to VDD. More than 600 melon accessions are expected to be tested for disease resistance in M. cannonballus infested soil in Weslaco, Texas, USA, to identify resistance to VDD, and other important traits. So far, at most 7 lines were found to be resistant to VDD and some of them were used to develop elite, muskmelon inbred lines by pedigree breeding following single or double backcrosses. These elite parents were crossed to each other to develop the hybrids M3 and M4. They were also tested in the same infested field in Weslaco. The hybrids were grown using standard commercial practices followed by growers and when their fruits were ready, their roots were sampled as well as scored for disease severity to estimate high and mid-parent heterosis Our results indicate the existence of heterosis regarding resistance to VDD. Thus, resistant plant material can be developed and selection for resistance can be accomplished. 展开更多
关键词 MELONS Vine decline Disease Monosporascus cannonballus RESISTANCE HETEROSIS
下载PDF
Analysis of the relationship between blood pressure variability and subtle cognitive decline in older adults
7
作者 Hui-Feng Guo Yi Wu +1 位作者 Jie Li Feng-Feng Pan 《World Journal of Psychiatry》 SCIE 2023年第11期872-883,共12页
BACKGROUND Blood pressure variability(BPV)has been shown to be related to mild cognitive impairment and Alzheimer's disease in a number of studies.However,the relationship between BPV and subtle cognitive decline(... BACKGROUND Blood pressure variability(BPV)has been shown to be related to mild cognitive impairment and Alzheimer's disease in a number of studies.However,the relationship between BPV and subtle cognitive decline(SCD)has received minimal attention in this field of research to date and has rarely been reported.AIM To examine whether SCD is independently associated with changes in BPV in older adults.METHODS Participants were selected based on having participated in cognitive function evaluation and ambulatory blood pressure measurement at the Shanghai Sixth People's Hospital Affiliated with Shanghai Jiao Tong University School of Medicine between June 2020 and August 2022.The participants included 182 individuals with SCD as the experimental group and 237 with normal cognitive function as the control group.The basic data,laboratory examinations,scale tests,and ambulatory blood pressure test results of the two groups were analyzed retrospectively,and the relationship between SCD and BPV was subsequently evaluated.RESULTS Significant differences were observed between the two groups of participants(P<0.05)in terms of age,education level,prevalence rate of diabetes,fasting blood glucose level,24-h systolic blood pressure standard deviation and coefficient of variation,24-h diastolic blood pressure standard deviation and coefficient of variation.The scale monitoring results showed significant differences in the scores for memory,attention,and visual space between the experimental and control groups.Logistic regression analysis indicated that age,education level,blood sugar level,and BPV were factors influencing cognitive decline.Linear regression analysis showed that there was an independent correlation between blood pressure variation and SCD,even after adjusting for related factors.Each of the above differences was still significant.CONCLUSION This study suggests that increased BPV is associated with SCD. 展开更多
关键词 Blood pressure VARIABILITY ELDERLY Subtle cognitive decline relationship
下载PDF
Effects of SPAD Decline Value of Mid-season Hybrid Rice Leaves after Full-heading Stage on Productivity of Rice Fertilized with Nitrogen 被引量:1
8
作者 徐富贤 何希德 +5 位作者 熊洪 张林 郭晓艺 朱永川 周兴兵 刘茂 《Agricultural Science & Technology》 CAS 2013年第1期149-154,共6页
[Objective] The aim was to research relationship between SPAD decline index after full-heading stage (SDIFHS) and productivity of rice. fertilized with nitro- gen in order to provide theoretical and practical refere... [Objective] The aim was to research relationship between SPAD decline index after full-heading stage (SDIFHS) and productivity of rice. fertilized with nitro- gen in order to provide theoretical and practical references for selection and breed- ing of rice varieties. [Method] From 2008 to 2010, 18 mid-season hybrid rice vari- eties were researched every year to explore relationship' between SDIFHS and pro- ductivity of rice fertilized with nitrogen. [Result] The productivity of rice fertilized with nitrogen was of extremely significant positive corretation with SDIFHS, because the higher SPAD decline index is, the higher LAI decline index and the transformation ratio of dry matter to spikes in overground plant would be. [Conclusion] The re- search established a new method to predict productivity of rice fertilized with nitro- gen based on SPAD decline index. 展开更多
关键词 Mid-season hybrid rice decline index of SPAD value Productivity of rice fertilized with nitrogen
下载PDF
西北欧全新世中期的Elm Decline研究新进展 被引量:5
9
作者 黄春长 《地球科学进展》 CAS CSCD 1996年第5期487-492,共6页
在5000aBP西北欧发生的ElmDecline,是全新世突发性环境事件或灾变过程的表现。它在60年来一直是欧洲环境变迁、考古和(14)C年代学界关。C的热点论题。对其研究进展作了系统的评述,以了解其研究现状,促进我... 在5000aBP西北欧发生的ElmDecline,是全新世突发性环境事件或灾变过程的表现。它在60年来一直是欧洲环境变迁、考古和(14)C年代学界关。C的热点论题。对其研究进展作了系统的评述,以了解其研究现状,促进我国全新世环境变迁和人地关系演变科学研究。 展开更多
关键词 ELM decline 环境灾变 人类因素 西北欧 全新世
下载PDF
Recent tree growth decline unprecedented over the last four centuries in a Tibetan juniper forest 被引量:5
10
作者 Yu-Mei Mou Ouya Fang +1 位作者 Xuehan Cheng Hongyan Qiu 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第4期1429-1436,共8页
Forest structure and function are subject to risks of growth declines from intensified drought and frequent extreme events related to climate warming.Knowledge of tree growth declines will help anticipate future respo... Forest structure and function are subject to risks of growth declines from intensified drought and frequent extreme events related to climate warming.Knowledge of tree growth declines will help anticipate future responses of forests to climate change.In this study,we investigated tree growth declines over the last four centuries in a juniper forest on the eastern Tibetan Plateau.By analyzing the radial growth trajectories of individual trees,we identified two events of intense growth decline,one in 1817–1830 and the other in 1969–1999 over the past four centuries.The intensity of the recent decline was unprecedented in the period under study.Ring-width chronology showed a positive correlation with self-calibrating Palmer Drought Severity Indices and a negative correlation with mean monthly temperatures in May and June.The recent intensified growth decline may have been due to temperatureinduced frequent droughts in the study area.Our findings suggest that trees in this juniper forest may face a higher risk of growth decline and even mortality under continued climate warming. 展开更多
关键词 Climate change DENDROECOLOGY DROUGHT FOREST health Growth decline
下载PDF
Preventive Effect of Gastrodin on Cognitive Decline after Cardiac Surgery with Cardiopulmonary Bypass:A Double-Blind,Randomized Controlled Study 被引量:10
11
作者 张曌 马璞 +4 位作者 徐尤年 詹美俊 张允健 姚尚龙 张诗海 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2011年第1期120-127,共8页
Cognitive decline is a common complication after cardiac surgery with cardiopulmonary bypass(CPB),but as such no pharmacological therapy has been shown to be efficacious in preventing the decline.However,gastrodin h... Cognitive decline is a common complication after cardiac surgery with cardiopulmonary bypass(CPB),but as such no pharmacological therapy has been shown to be efficacious in preventing the decline.However,gastrodin has been shown to have multi-pharmacological effects on neurological functions.We undertook this study to test the hypothesis that gastrodin would potentially prevent CPB-associated neurocognitive decline.We randomly assigned 200 patients undergoing mitral valve replacement surgery to receive either gastrodin(40 mg/kg) or saline after the induction of anesthesia and subsequently evaluated cognitive function before surgery,at discharge,and at 3rd month after surgery by using a battery of five neurocognitive tests,or adverse effects of gastrodin postoperatively.Neurocognitive decline in postoperative function was defined as a drop of 1 SD or more in the scores on tests of any one of the four domains of cognitive function.Cognitive decline occurred in 9% of the patients in the gastrodin group in contrast to 42% in the control group(P〈0.01) at discharge.Cognitive outcome could be determined at 3rd month in 87 patients in the gastrodin group and 89 in the control group.Cognitive decline was detected in 6% in the gastrodin group and 31% in the control group(P〈0.01).The incidences of possible adverse effects were similar between two groups.These results indicate that gastrodin is an effective and a safe drug for the prevention of neurocognitive decline in patients undergoing mitral valve replacement surgery with CPB. 展开更多
关键词 GASTRODIN cardiopulmonary bypass cognitive decline
下载PDF
Decline of eucalypt trees in tablelands of New South Wales, Australia 被引量:6
12
作者 ZHANG Yan-hua SUN Li-fu Ken C. Hodgkinson 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第4期306-310,共5页
Eucalyptus species are the native and major plant group in Australian landscapes. Since European settlement, eucalypt trees heavily decline in the tablelands .of New South Wales. Tree recruitment bog down and the land... Eucalyptus species are the native and major plant group in Australian landscapes. Since European settlement, eucalypt trees heavily decline in the tablelands .of New South Wales. Tree recruitment bog down and the landscape ecosystem hardly recovers to the original state. This paper introduces the history of eucalypt trees and native shrubs decline, analyzes reasons of seedling recruitment decrease in this region, such as clearing, grazing, fire, competition from exotic species, dieback, insects, drought and so on, and summarizes the probable conditions of eucalypt tree recruitment, such as suitable conditions of seedling survival, sufficient seed supply, keep from predation, suitable germination conditions, non-grazed environment, mechanical treatment, weed control, fire regime, disease control etc, lending suggests how to preserve and encourage eucalypt trees recruitment in the area. 展开更多
关键词 EUCALYPT decline RECRUITMENT
下载PDF
Risks of rapid decline renal function in patients with type 2 diabetes 被引量:5
13
作者 Yi-Jing Sheen Wayne HH Sheu 《World Journal of Diabetes》 SCIE CAS 2014年第6期835-846,共12页
Progressive rising population of diabetes and related nephropathy, namely, diabetic kidney disease and associated end stage renal disease has become a major global public health issue. Results of observational studies... Progressive rising population of diabetes and related nephropathy, namely, diabetic kidney disease and associated end stage renal disease has become a major global public health issue. Results of observational studies indicate that most diabetic kidney disease progresses over decades; however, certain diabetes patients display a rapid decline in renal function, which may lead to renal failure within months. Although the definition of rapid renal function decline remained speculative, in general,it is defined by the decrease of estimated glomerular filtration rate(e GFR) in absolute rate of loss or percent change. Based on the Kidney Disease: Improving Global Outcomes 2012 clinical practice guidelines, a rapid decline in renal function is defined as a sustained declinein e GFR of 】 5 m L/min per 1.73 m2 per year. It has been reported that potential factors contributing to a rapid decline in renal function include ethnic/genetic and demographic causes, smoking habits, increased glycated hemoglobin levels, obesity, albuminuria, anemia, low serum magnesium levels, high serum phosphate levels, vitamin D deficiency, elevated systolic blood pressure, pulse pressure, brachial-ankle pulse wave velocity values, retinopathy, and cardiac autonomic neuropathy. This article reviews current literatures in this area and provides insight on the early detection of diabetic subjects who are at risk of a rapid decline in renal function in order to develop a more aggressive approach to renal and cardiovascular protection. 展开更多
关键词 Type 2 diabetes Diabetic kidney disease Rapid decline Estimated glomerular filtration rate ALBUMINURIA
下载PDF
Blasingame production decline type curves for analysing a multi-fractured horizontal well in tight gas reservoirs 被引量:4
14
作者 魏明强 段永刚 +3 位作者 陈伟 方全堂 李政澜 郭希冉 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第2期394-401,共8页
Production decline analysis has been considered as an important method to obtain the flow parameters, reservoir properties and original gas in place. Although advanced Blasingame production decline analysis methods fo... Production decline analysis has been considered as an important method to obtain the flow parameters, reservoir properties and original gas in place. Although advanced Blasingame production decline analysis methods for vertical wells, fractured wells and horizontal wells are widely used, limited study has conducted on Blasingame production decline type curves for multi-fractured horizontal well(MFHW). Based on the perpendicular bisection(PEBI) grids, a numerical model was developed and the solution was obtained using control volume finite element method and the fully implicit method. Blasingame production decline-type curves of the infinitely conductive MFHW were plotted through computer programming. A field case was presented to analyse and verify the model developed. Five flow regimes, including early formation linear flow, early radial flow, compound linear flow, transient flow and pseudo-radial flow, are recognized. Fracture spacing is the main factor that affects early radial flow, compound linear flow and transient flow, the distance from the well to the circular boundary affects the pseudo-radial flow, and the type curves are also significantly affected by the formation permeability, fracture number and fracture half-length. The validation of field case suggests that the Blasingame production decline type curves proposed in this work can be applied to the production decline analysis for MFHW in tight gas reservoirs. 展开更多
关键词 tight gas reservoir fractured horizontal well unstructured grid production decline type curves
下载PDF
Characterisation of pH decline and meat color development of beef carcasses during the early postmortem period in a Chinese beef cattle abattoir 被引量:4
15
作者 ZHANG Yi-min David L.Hopkins +5 位作者 ZHAO Xiao-xiao Remy van de Ven MAO Yan-wei ZHU Li-xian HAN Guang-xing LUO Xin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第7期1691-1695,共5页
This study investigated the pH/temperature decline of beef carcasses in a typical Chinese abattoir and color development as pH declined during rigor onset. A natural cubic spline model was used to model the pH/tempera... This study investigated the pH/temperature decline of beef carcasses in a typical Chinese abattoir and color development as pH declined during rigor onset. A natural cubic spline model was used to model the pH/temperature decline for those carcasses which passed through pH 6.0. Six of the 97 carcasses that exhibited a high (-〉6.10) ultimate pH (pHu) (darkcutting) in the M. Iongissimus lumborum (LL) were sampled, along with the same numbers of normal pHu and intermediate pHu carcasses (5.40-5.79; 5.80-6.10, respectively), to examine color development within 24 h postmortem. It was shown that 66.7% of the modeled carcasses were outside the ideal pH/temperature window with a temperature@pH6.0 lower than ideal, suggesting the need for acceleration of the pH decline. The stable and low a^*, b^* and chroma values of high pHu beef within the first 12 h indicated dark-cutting beef might be detected earlier than expected. 展开更多
关键词 pH decline color ultimate pH dark-cutting beef
下载PDF
Rise and decline of ancient salt industry revealed by Na and Ca concentrations in sediments at Zhongba site, Chongqing 被引量:4
16
作者 ZHU Cheng JIANG Fengqing +5 位作者 MA Chunmei XU Weifeng HUANG Linyan ZHENG Chaogui LI Lan SUN Zhibin 《Journal of Geographical Sciences》 SCIE CSCD 2008年第3期328-340,共13页
Based on dynastic period division and AMS ^14 C dating performed on the sedimentary layers at Zhongba and Yuxi sites,and also the analysis of Na,Ca and Mg of 201 sedimentary samples from Zhongba site and that of Ca an... Based on dynastic period division and AMS ^14 C dating performed on the sedimentary layers at Zhongba and Yuxi sites,and also the analysis of Na,Ca and Mg of 201 sedimentary samples from Zhongba site and that of Ca and Na in 47 sedimentary samples from Yuxi by using an inductively coupled plasma-mass spectrometry(ICP),we found that there were 35 time periods when the contents of Ca and Na were reversely correlated,i.e.whenever the content of Ca was the highest,the content of Na was the lowest,and vice versa. Among them,there were 21 time periods when the content of Ca was the highest,and Na was the lowest,indicating that there were about 21 prosperous periods of ancient salt production at Zhongba site since 3000BC.Other 14 time periods with the peak values of Na while the low values of Ca indicate 14 declined periods of salt production at Zhongba site since 3000BC.The conclusion obtained from the reverse relationship between Ca and Na contents in this paper is consistent with that"the salt production at Zhongba site started in the new stone age,developed in the Xia and Shang dynasties,reached at the heyday in periods from the Western Zhou to the Han Dynasties,maintained stable to develop in the Tang and the Song dynasties,and gradually declined after the Song Dynasty because the sea salt were conveyed into Sichuan region,however,still had production in the 1970s-1980s",educed from archeological exploration.All the above mentioned results indicate that there is a reverse relationship obviously between the contents of Na and Ca in sediments at Zhongba site for ancient salt production,which can be used to reveal the process of rise and decline of ancient salt industry at Zhongba site. 展开更多
关键词 Zhongba site Zhongxian County reverse relationship between contents of Na and Ca rise and decline of early salt production
下载PDF
A continuing 30-year decline in water quality of Jiaojiang Estuary, China 被引量:3
17
作者 Chun-ye Wang Bin Zhou Bei Huang 《Water Science and Engineering》 EI CAS CSCD 2015年第1期20-29,共10页
A quantitative description of a long-term series of aquatic environmental factors and their spatial distributions was generated using measured data from the Jiaojiang Estuary from 1982 to 2011. The aquatic environment... A quantitative description of a long-term series of aquatic environmental factors and their spatial distributions was generated using measured data from the Jiaojiang Estuary from 1982 to 2011. The aquatic environmental factors included suspended matter, salinity, and nutrients. Based on these factors, the aquatic ecosystem health in the Jiaojiang Estuary over the last 30 years was analyzed. The results indicated that the suspended matter concentration in the estuary was mainly affected by the amounts of suspended sediment and solid waste, with the value fluctuating over a long period, and the range of high concentration expanded continually; the salinity was mainly affected by precipitation and surface water resources, showing an overall decreasing trend, and the region with low salinity moved seaward and toward the reclamation areas; and the nutritional status, mainly affected by discharge of industrial wastewater and domestic sewage, was satisfactory in the 1980s and 1990s, but the status became severe in recent years. Reclamation had a great influence on these three factors: high reclamation strength led to a significant increase in the suspended matter concentration and a deterioration of the nutritional status, and the reclamation rate was negatively related with the salinity in the estuary. There was a significant positive correlation between the health status of the aquatic ecosystem and salinity, with a correlation coefficient of 0.93. The correlation coefficient between the health status and nutritional status was -0.71, while the correlation between the suspended matter concentration and health status was not as significant as that of the other two factors. The dynamics of the aquatic environment could be divided into four stages: sustainable health from the 1980s to the 1990s, continued deterioration from 2000 to 2003, improvement from 2004 to 2005, and secondary deterioration from 2006 to 2011. The Jiaojiang Estuary is faced with imminent environmental pressure at present. 展开更多
关键词 Water quality decline Aquatic ecosystem health Aquatic environmental factor Suspended matter concentration SALINITY Nutritional status Jiaojiang Estuary
下载PDF
The influence of gut microbiota alteration on age-related neuroinflammation and cognitive decline 被引量:2
18
作者 Amsha S.Alsegiani Zahoor A.Shah 《Neural Regeneration Research》 SCIE CAS CSCD 2022年第11期2407-2412,共6页
Recent emerging research on intestinal microbiota and its contribution to the central nervous system during health and disease has attra cted significant attention.Age-related intestinal microbiota changes initiate br... Recent emerging research on intestinal microbiota and its contribution to the central nervous system during health and disease has attra cted significant attention.Age-related intestinal microbiota changes initiate brain aging and age-related neurodegenerative disorders.Aging is one of the critical predisposing risk factors for the development of neurodegenerative diseases.Maintaining a healthy gut microbiota is essential for a healthy body and aging,but dys biosis could initiate many chro nic diseases.Understanding the underlying mechanisms of gut microbiota alterations/dys biosis will help identify biomarkers for aging-related chro nic conditions.This review summarizes recent advances in micro biota-neurodegenerative disease research and will enhance our unde rstanding of gut microbiota dys biosis and its effects on brain aging. 展开更多
关键词 brain aging cognitive decline DYSBIOSIS fecal microbiota transplantation gut-microbiota NEUROINFLAMMATION PREBIOTICS PROBIOTICS
下载PDF
The decline process and major pathways of Microcystis bloom in Taihu Lake, China 被引量:2
19
作者 WANG Zhicong LI Guowen +1 位作者 LI Genbao LI Dunhai 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2012年第1期37-46,共10页
Eutrophication has become a serious concern in many lakes, resulting in cyanobacterial blooms. However, the mechanism and pathways of cyanobacteria decline are less understood. To identify and define the growth and de... Eutrophication has become a serious concern in many lakes, resulting in cyanobacterial blooms. However, the mechanism and pathways of cyanobacteria decline are less understood. To identify and define the growth and decline of Microcystis blooms in Taihu Lake of China, and to illuminate the destination of surface floating blooms, we investigated the biomass distribution and variations in colony size, morphology, and floating velocity from October 2008 to September 2009. The results showed that the Microcystis bloom declined in response to biomass decrease, colony disaggregation, buoyancy reduction, and increased phytoplankton biodiversity, and these indicative parameters could be applied for recognition of the development phases of the bloom. Three major decline pathways were proposed to describe the bloom decline process, colony disaggregation (Pathway I), colony settlement (Pathway II), and cell lysis in colonies (Pathway III). We proposed a strategy to define the occurrence and decline of Microcystis blooms, to evaluate the survival state under different stress conditions, and to indicate the efficiency of controlling countermeasures against algal blooms. 展开更多
关键词 Microcystis blooms decline pathways morphological changes biomass distribution Taihu Lake
下载PDF
Decline and dieback of cork oak(Quercus suber L.)forests in the Mediterranean basin:a case study of Kroumirie,Northwest Tunisia 被引量:2
20
作者 Issam Touhami E.Chirino +4 位作者 H.Aouinti A.El Khorchani M.T.Elaieb A.Khaldi Z.Nasr 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第5期1461-1477,共17页
Assessing the vulnerability of forest ecosystems in the climate change context is a challenging task as the mechanisms that determine this vulnerability cannot be directly observed.Based on the ecological interrelatio... Assessing the vulnerability of forest ecosystems in the climate change context is a challenging task as the mechanisms that determine this vulnerability cannot be directly observed.Based on the ecological interrelationships between forests and climate,the present review focused on providing current information about vulnerability assessments of cork oak(Quercus suber L.)forests in the Mediterranean basin,especially,in the Kroumirie region(northwest Tunisia),currently under historic extreme drought conditions.From comparing recent findings in this region,we synthesized data on cork oak decline and mortality collected during the historic drought years 1988–1995 period.Climate change impacts cork forest decline,with special interest shown in elevated temperatures and drought;cork oak forest regeneration,and the adaptation of the Kroumirie forest to climate change,are reviewed herein.The studied region has been influenced largely by frequent prolonged drought periods,especially from 1988 to 1995.Droughts were found to consistently have a more detrimental impact on the growth and mortality rates of cork oak populations.Cork oak mortality was recorded for up to 63,622 trees.In the future,more research studies and observational data will be needed,which could represent an important key to understand ecosystem processes,and to facilitate the development of better models that project climate change impacts and vulnerability.The study is useful for researchers and forestry decision makers to develop the appropriate strategies to restore and protect ecosystems,and to help anticipate potential future droughts and climate change. 展开更多
关键词 Climate change Drought effect Forest decline Tree mortality Mediterranean forest
下载PDF
上一页 1 2 18 下一页 到第
使用帮助 返回顶部