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Diagnostic and prognostic implications of non-high-density lipoprotein cholesterol and homocysteine levels for cognitive impairment in thalamic infarction
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作者 Shan-Yao Zhu Wei Ge Huan Zhang 《World Journal of Psychiatry》 SCIE 2023年第12期985-994,共10页
BACKGROUND Patients with thalamic infarction experience abnormal blockages of multinuc-leated vessels,affecting the body and thereby the thalamus.Most patients with thalamic infarction have an adverse prognosis,which ... BACKGROUND Patients with thalamic infarction experience abnormal blockages of multinuc-leated vessels,affecting the body and thereby the thalamus.Most patients with thalamic infarction have an adverse prognosis,which seriously affects their safety.Therefore,it is essential to analyze the independent risk factors that influence the prognosis of patients with thalamic infarction and develop corresponding preventive measures.AIM To explore the effect of non-high-density lipoprotein cholesterol(non-HDL-C)and Homocysteine(Hcy)levels in cognitive impairment in thalamic infarction.METHODS From March 2019 to March 2022,80 patients with thalamic infarction were divided into a group with cognitive impairment[Montreal Cognitive Assessment(MoCA)score<26;35 patients]and a group with normal cognitive function(MoCA score of 26-30;45 patients)according to the MoCA score.In addition,50 healthy people in the same period were selected as the control group.A correlation between the non-HDL-C and Hcy levels and the MoCA score and receiver operating characteristic curve was observed,and the serum non-HDL-C and Hcy levels were analyzed for the diagnosis of cognitive impairment in patients with thalamic infarction.According to the Modified Rankin Scale(MRS)score,80 patients with thalamic infarction were divided into a good prognosis group(MRS score≤2)and a poor prognosis group(MRS score>2).RESULTS The non-HDL-C and Hcy levels were significantly higher in the group with cognitive impairment than in the group with normal cognitive function(P<0.05).There was no significant difference in the non-HDL-C level between the control group and the group with normal cognitive function(P>0.05).The MoCA scores of the group with cognitive impairment were significantly lower than those of the group with normal cognitive function and the control group(P<0.05).There was a significant difference between the control group and the group with normal cognitive function(P<0.05).The non-HDL-C and Hcy levels were correlated with the MoCA score(P<0.05),cognitive impairment[areas under the curve(AUC)=0.709,95%confidence interval(95%CI):0.599-0.816],the non-HDL-C level,and could predict cognitive impairment in patients with thalamic infarction(AUC=0.738,95%CI:0.618-0.859).Hcy combined with non-HDL-C levels can predict cognitive impairment in patients with thalamic infarction(AUC=0.769,95%CI:0.721-0.895).RESULTS There were 50 patients in the good prognosis group and 30 patients in the poor prognosis group.Compared with the good prognosis group,in the poor prognosis group,the National Institutes of Health Stroke Scale(NIHSS)score,non-HDL-C level,Hcy level,large-area cerebral infarction,atrial fibrillation,and activated partial prothrombin time were statistically significant(P<0.05).The non-HDL-C level,the Hcy level,the NIHSS score,extensive cerebral serum,and atrial fibrillation may all be independent risk factors for poor prognosis in patients with thalamic infarction(P<0.05).CONCLUSION Non-HDL-C and Hcy levels are positively correlated with cognitive impairment in patients with thalamic infarction.Non-HDL-C and Hcy levels can be used in the diagnosis of cognitive impairment in patients with thalamic infarction,and the combined detection effect is better.The main factors affecting the prognosis of patients with thalamic infarction are the non-HDL-C level,the Hcy level,the NIHSS score,large-area cerebral infarction,and atrial fibrillation.Clinically,corresponding preventive measures can be formulated based on the above factors to prevent poor prognosis and reduce mortality. 展开更多
关键词 Thalamic infarction Cognitive impairment Non-high-density lipoprotein cholesterol high homocysteine level Diagnostic value PROGNOSIS Influencing factors Correlation
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Theory and Practice of High-Level Sprint Training Based on Accurate Sectional Timing
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作者 XING Yu ZHU Detao +2 位作者 YANG Qin ZHAO Wenxiang CAO Zhi 《Journal of Sports Science》 2023年第1期7-15,共9页
There is an obvious gap in sprint level at home and abroad,and there are different opinions on the reasons.According to the analysis,physical energy and its distribution in each segment are the main factors restrictin... There is an obvious gap in sprint level at home and abroad,and there are different opinions on the reasons.According to the analysis,physical energy and its distribution in each segment are the main factors restricting the sprint performance in China.Different from middle and long-distance running,we must rely on accurate sectional timing technology to master the law of speed-physical energy change in the process of sprint.Each stage is an integral part of the whole dash process,and each part restricts each other.Each stage has a relative best achievement.Simply pursuing the optimal state of segment is not only not helpful to the final result,but also counterproductive. 展开更多
关键词 Accurate sectional timing high level sprint training speed-physical energy change law.
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Potassium alleviated high nitrogen-induced apple growth inhibition by regulating photosynthetic nitrogen allocation and enhancing nitrogen utilization capacity
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作者 Xinxiang Xu Guangyuan Liu +10 位作者 Jingquan Liu Mengxue Lyu Fen Wang Yue Xing Hao Meng Min Li Yu Jiang Ge Tian Zhanling Zhu Yuanmao Jiang Shunfeng Ge 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第1期1-14,共14页
There is a close relationship between potassium(K)and nitrogen(N).However,the roles of K under high N conditions remain unclear.Using a hydroponics approach,we monitored the morphological,physiological,and molecular c... There is a close relationship between potassium(K)and nitrogen(N).However,the roles of K under high N conditions remain unclear.Using a hydroponics approach,we monitored the morphological,physiological,and molecular changes in M9T337 apple(Malus domestica)rootstocks under different nitrate(10 and 30 mmol·L^(-1)NO_(3)^(-))and K supply(0.5,6,10,and 20 mmol·L_(-1)K^(+))conditions.Results revealed that high nitrate inhibited the root growth of M9T337 rootstocks,downregulated the expressions of K transporter genes(MdPT5,MdHKT1,and MdATK1),and reduced the net NO3-and K+influx at the surface of roots,thereby resulting in an N/K imbalance in rootstocks.Further investigation showed that 10 mmol·L^(-1)K increased the activity of N metabolic enzymes(NR,GS,NiR,and GOGAT),upregulated the expressions of genes related to nitrate uptake and transport(MdNRT1.1,MdNRT1.2,MdNRT1.5,and MdNRT2.4),promoted15N transport from the roots to the shoots,optimized leaf N distribution,and improved photosynthetic N utilization efficiency under high nitrate conditions.These results suggest that the negative effects of high nitrate may be related to the N/K imbalance and that reducing N/K in plants by increasing K supply level can effectively alleviate the inhibition of N assimilation by high nitrate stress. 展开更多
关键词 Apple rootstock K level high nitrate stress N metabolism ^(15)N
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Intermolecular Acid-Base-Pairs Containing Poly(p-Terphenyl-co-lsatin Piperidinium)for High Temperature Proton Exchange Membrane Fuel Cells
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作者 Xiaofeng Hao Zhen Li +6 位作者 Min Xiao Zhiheng Huang Dongmei Han Sheng Huang Wei Liu Shuanjin Wang Yuezhong Meng 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第3期406-414,共9页
How to optimize and regulate the distribution of phosphoric acid in matrix,and pursuing the improved electrochemical performance and service lifetime of high temperature proton exchange membrane(HT-PEMs)fuel cell are ... How to optimize and regulate the distribution of phosphoric acid in matrix,and pursuing the improved electrochemical performance and service lifetime of high temperature proton exchange membrane(HT-PEMs)fuel cell are significant challenges.Herein,bifunctional poly(p-terphenyl-co-isatin piperidinium)copolymer with tethered phosphonic acid(t-PA)and intrinsic tertiary amine base groups are firstly prepared and investigated as HT-PEMs.The distinctive architecture of the copolymer provides a well-designed platform for rapid proton transport.Protons not only transports through the hydrogen bond network formed by the adsorbed free phosphoric acid(f-PA)anchored by the tertiary amine base groups,but also rely upon the proton channel constructed by the ionic cluster formed by the t-PA aggregation.Thorough the design of the structure,the bifunctional copolymers with lower PA uptake level(<100%)display prominent proton conductivities and peak power densities(99 mS cm^(-1),812 mW cm^(-2)at 160℃),along with lower PA leaching and higher voltage stability,which is a top leading result in disclosed literature.The results demonstrate that the design of intermolecular acid-base-pairs can improve the proton conductivity without sacrificing the intrinsic chemical stability or mechanical property of the thin membrane,realizing win-win demands between the mechanical robustness and electrochemical properties of HT-PEMs. 展开更多
关键词 bifunctional copolymer high temperature proton exchange membrane intermolecular acid-base-pairs phosphonic acid retention phosphonic acid uptake level
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HOG-VGG:VGG Network with HOG Feature Fusion for High-Precision PolSAR Terrain Classification
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作者 Jiewen Li Zhicheng Zhao +2 位作者 Yanlan Wu Jiaqiu Ai Jun Shi 《Journal of Harbin Institute of Technology(New Series)》 CAS 2024年第5期1-15,共15页
This article proposes a VGG network with histogram of oriented gradient(HOG) feature fusion(HOG-VGG) for polarization synthetic aperture radar(PolSAR) image terrain classification.VGG-Net has a strong ability of deep ... This article proposes a VGG network with histogram of oriented gradient(HOG) feature fusion(HOG-VGG) for polarization synthetic aperture radar(PolSAR) image terrain classification.VGG-Net has a strong ability of deep feature extraction,which can fully extract the global deep features of different terrains in PolSAR images,so it is widely used in PolSAR terrain classification.However,VGG-Net ignores the local edge & shape features,resulting in incomplete feature representation of the PolSAR terrains,as a consequence,the terrain classification accuracy is not promising.In fact,edge and shape features play an important role in PolSAR terrain classification.To solve this problem,a new VGG network with HOG feature fusion was specifically proposed for high-precision PolSAR terrain classification.HOG-VGG extracts both the global deep semantic features and the local edge & shape features of the PolSAR terrains,so the terrain feature representation completeness is greatly elevated.Moreover,HOG-VGG optimally fuses the global deep features and the local edge & shape features to achieve the best classification results.The superiority of HOG-VGG is verified on the Flevoland,San Francisco and Oberpfaffenhofen datasets.Experiments show that the proposed HOG-VGG achieves much better PolSAR terrain classification performance,with overall accuracies of 97.54%,94.63%,and 96.07%,respectively. 展开更多
关键词 PolSAR terrain classification high⁃precision HOG⁃VGG feature representation completeness elevation multi⁃level feature fusion
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Effects of Nitrogen Level and High Temperature Stress on Yield, SPAD Value and Soluble Sugar Content of Early Rice Ganxin 203 被引量:2
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作者 杨军 余秋英 +10 位作者 陈小荣 朱昌兰 彭小松 贺晓鹏 傅军如 欧阳林娟 边建民 胡丽芳 孙晓棠 徐杰 贺浩华 《Agricultural Science & Technology》 CAS 2016年第2期385-390,共6页
This study aimed to investigate the combined effects of nitrogen level (high and ordinary) and high temperature stress (37 ℃, 4 d) at the late panicle ini- tiation stage on yield, SPAD value and soluble sugar con... This study aimed to investigate the combined effects of nitrogen level (high and ordinary) and high temperature stress (37 ℃, 4 d) at the late panicle ini- tiation stage on yield, SPAD value and soluble sugar content of Ganxin 203, an early rice cultivar. The results showed that under both high and ordinary nitrogen levels, high temperature stress reduced the seed-setting rate, yield per stem, SPAD value and soluble sugar content of Ganxin 203; under both high and ordinary tem- peratures, high nitrogen level increased the seed-setting rate, yield per stem and soluble sugar content of Ganxin 203; the seed-setting rate, yield per stem and yield per plant of Ganxin 203 under high temperature and high nitrogen level were higher than those under high temperature and ordinary nitrogen level. It suggests that ap- propriate high nitrogen level contributes to weakening the negative effects of high temperature stress on rice yield. 展开更多
关键词 RICE Late panicle initiation stage high temperature YIELD SPAD value Nitrogen level
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Coral Reef and High Sea Level at Luhuitou, Hainan Island during the Holocene 被引量:2
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作者 黄德银 施祺 张叶春 《Marine Science Bulletin》 CAS 2007年第2期61-70,共10页
According to the field survey and ^14C dating at Luhuitou, southern Hainan Island, a subsiding area, the authors conclude the high sea level history recorded by coral reef in the Holocene. At least 4 sea level high-st... According to the field survey and ^14C dating at Luhuitou, southern Hainan Island, a subsiding area, the authors conclude the high sea level history recorded by coral reef in the Holocene. At least 4 sea level high-stands can be identified from the distribution of coral reef ages: 7300 - 6000 cal.aBP, 4800 - 4700 cal.aBP, 4300 - 4200 cal.aBP and 3100 - 2900 cal.aBP. The highest sea level occurred around 7300 - 6700 cal.aBP, and biological-morphological zones took their shape during the stage. The later coral reefs developed in ponds, depressions, and developed outwards on both sides of Luhuitou peninsula. The modern coral reefs are developing in out reef flat and reef-front slope. Moreover, the time of high sea levels in the northern South China Sea recorded by coral reefs in the Luhuitou peninsula can link up with that in other parts of South China Sea. That means the high sea levels in the South China Sea during the Holocene, which are relative to the warming climate, have the global background. 展开更多
关键词 coral reef high sea level Luihuitou HOLOCENE
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Individualized management of pregnant women with high hepatitis B virus DNA levels 被引量:15
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作者 Zhao Zhang Chao Chen +2 位作者 Zhe Li Ying-Hua Wu Xiao-Min Xiao 《World Journal of Gastroenterology》 SCIE CAS 2014年第34期12056-12061,共6页
Hepatitis B is a major health concern in the Asia-Pacific region, and is endemic in China, Southeast Asia, and Africa. Chronic hepatitis B virus (HBV) infection may cause hepatic cirrhosis and liver cancer. It is esti... Hepatitis B is a major health concern in the Asia-Pacific region, and is endemic in China, Southeast Asia, and Africa. Chronic hepatitis B virus (HBV) infection may cause hepatic cirrhosis and liver cancer. It is estimated that there are more than 350 million chronic HBV carriers worldwide, of whom approximately one quarter will die of chronic hepatitis B-related liver diseases. HBV is transmitted horizontally through blood and blood products or by sexual transmission, and vertically from mother to infant. Perinatal infection is the predominant mode of transmission in countries with a high prevalence of hepatitis B surface antigen (HBsAg) carriage, and perinatal transmission leads to high rates of chronic infection. Therefore, it is important to prevent the mother-to-child transmission (MTCT) of HBV. Research has shown that pregnant women with high HBV DNA levels have an increased risk of MTCT. However, most of the obstetrics guidelines do not make a distinction between pregnant women with high HBV DNA levels and those who are HBsAg positive only. This review addresses the management of pregnant women with high levels of HBV viremia, in terms of antiviral therapy, use of hepatitis B immunoglobulin (HBIG), the combined application of hepatitis B vaccine and HBIG, choice of delivery mode and feeding practices. (C) 2014 Baishideng Publishing Group Inc. All rights reserved. 展开更多
关键词 Hepatitis B virus Hepatitis B virus DNA high level MANAGEMENT PREGNANCY
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The effects of high temperature level on square Bt protein concen-tration of Bt cotton 被引量:3
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作者 WANG Jun CHEN Yuan +5 位作者 YAO Meng-hao LI Yuan WEN Yu-jin CHEN Yuan ZHANG Xiang CHEN De-hua 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第10期1971-1979,共9页
Higher boll worm survival rates were detected after high temperature presented during square period in Bt cotton. The objective of this study was to investigate the effects of high temperature level on the Bt efficacy... Higher boll worm survival rates were detected after high temperature presented during square period in Bt cotton. The objective of this study was to investigate the effects of high temperature level on the Bt efficacy of two different types of Bt cotton cultivars at squaring stage. During the 2011 to 2013 cotton growth seasons, high temperature treatments ranged from 34 to 44°C in climate chambers, and field experiments under high temperature weather with various temperature levels were conducted to investigate the effects of the high temperature level on square Bt protein concentration and nitrogen metabolism. The climate chamber experiments showed that the square insecticidal protein contents reduced after 24 h elevated temperature treatments for both cultivars, whereas significant declines of the square insecticidal protein contents were detected at temperature 〉38°C, and only slightly numerical reductions were observed when temperature below 38°C. Similar high temperature responses were also observed at the two field experimental sites in 2013. Correspondingly, high temperature below 38°C seems have little effect on the square amino acid concentrations, soluble protein contents, glutamic-pyruvic transaminase(GPT) and glutamic-oxalacetic transaminase(GOT) activities as well as protease and peptidase activities; however, when the temperature was above 38°C, reduced soluble protein contents, enhanced amino acid concentrations, decreased GPT and GOT activities, bolstered protease and peptidase activities in square were detected. In general, the higher the temperature is(〉38°C), the larger the changes for the above compound contents and key enzymes activities of the square protein cycle. The findings indicated that the unstable insect resistance of the square was related to high temperature level during square stage. 展开更多
关键词 Bt cotton SQUARE high temperature level STRESS Bt protein nitrogen metabolism
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High level architecture evolved modular federation object model 被引量:3
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作者 Wang Wenguang Xu Yongping +3 位作者 Chen Xinx Chen Xin Li Qun Wang Weiping 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第3期625-635,共11页
To improve the agility, dynamics, composability, reusability, and development efficiency restricted by monolithic federation object model (FOM), a modular FOM is proposed by high level architecture (HLA) evolved p... To improve the agility, dynamics, composability, reusability, and development efficiency restricted by monolithic federation object model (FOM), a modular FOM is proposed by high level architecture (HLA) evolved product development group. This paper reviews the state-of-the-art of HLA evolved modular FOM. In particular, related concepts, the overall impact on HLA standards, extension principles, and merging processes are discussed. Also permitted and restricted combinations, and merging rules are provided, and the influence on HLA interface specification is given. The comparison between modular FOM and base object model (BOM) is performed to illustrate the importance of their combination. The applications of modular FOM are summarized. Finally, the significance to facilitate compoable simulation both in academia and practice is presented and future directions are pointed out. 展开更多
关键词 MODEL federation object model REVIEW modular federation object model base object model COMPOSABILITY high level architecture evolved simulation.
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System-on-Chip Design Using High-Level Synthesis Tools 被引量:7
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作者 Erdal Oruklu Richard Hanley +3 位作者 Semih Aslan Christophe Desmouliers Fernando M. Vallina Jafar Saniie 《Circuits and Systems》 2012年第1期1-9,共9页
This paper addresses the challenges of System-on-Chip designs using High-Level Synthesis (HLS). HLS tools convert algorithms designed in C into hardware modules. This approach is a practical choice for developing comp... This paper addresses the challenges of System-on-Chip designs using High-Level Synthesis (HLS). HLS tools convert algorithms designed in C into hardware modules. This approach is a practical choice for developing complex applications. Nevertheless, certain hardware considerations are required when writing C applications for HLS tools. Hence, in order to demonstrate the fundamental hardware design concepts, a case studyis presented. Fast Fourier Transform (FFT) implementation in ANSI C is examined in order to explore the important design issues such as concurrency, data recurrences and memory accesses that need to be resolved before generating the hardware using HLS tools. There are additional language constraints that need to be addressed including use of pointers, recursion and floating point types. 展开更多
关键词 System level DESIGN high level Synthesis Field PROGRAMMABLE GATE Arrays FOURIER Transform
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Middle Holocene warm period and sea level high in coastal areas,North China 被引量:1
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作者 孟广兰 韩有松 王少青 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2005年第2期252-258,共7页
Relevant geological, geographical, archaeological data were collected to study the characteristics of middle Holocene warm period and sea level high on North China coast. Middle Holocene climate and sea level change o... Relevant geological, geographical, archaeological data were collected to study the characteristics of middle Holocene warm period and sea level high on North China coast. Middle Holocene climate and sea level change on North China coast were correlated to warm marine environment events in about 8–3 ka B.P. The sea level in about 8 ka B.P. was higher than present mean sea level, then fluctuated for 5 000 years and after that it became even in 3 ka B.P. The highest sea level occurred in about 6–5 ka B.P.; the maximum was about 2–3 m and minimum was about 1–2 m. 展开更多
关键词 warm period sea level high middle Holocene North China coast
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Liquid nitrogen level meter for high-temperature superconductor (HTS) 被引量:1
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作者 PARK Heecheol JEONG Hwanjun +3 位作者 LEE Changyeung KIM Purn CHO Jangwon KIM Seokho 《Journal of Central South University》 SCIE EI CAS 2012年第11期3100-3104,共5页
Many kinds of high temperature superconductor (HTS) power machines such as HTS cable, HTS fault current limitcr and HTS magnet are cooled by liquid nitrogen. The level of liquid nitrogen should be monitored and cont... Many kinds of high temperature superconductor (HTS) power machines such as HTS cable, HTS fault current limitcr and HTS magnet are cooled by liquid nitrogen. The level of liquid nitrogen should be monitored and controlled to ensure the thermal stability and the dielectric strength as well. To measure the level, capacitance method and differential pressure method are usually used. However, each method has installation difficulties and measurement errors for unsteady state operation with varying system pressure. A new liquid level meter using a 2G HTS conductor is described, which has similar structure with the liquid helium level meter with NbTi filament. The level meter is fabricated with a parallel connected heater, which helps the separation of the superconducting region and normal region, considering the critical temperature, large heat capacity of conductor and cooling characteristics. The level of liquid nitrogen can be obtained from the measured voltage signal along the 2G HTS conductor. Design, fabrication and test results of the new liquid nitrogen level meter are presented. 展开更多
关键词 high temperature superconductivity liquid nitrogen level meter QUENCH
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Key Scientific Challenges in Geological Disposal of High Level Radioactive Waste 被引量:4
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作者 Wang Ju(Beijing Research Institute of Uranium Geology,China National Nuclear Corporation,Beijing 100029,P.R.China) 《工程科学(英文版)》 2007年第4期45-50,共6页
The geological disposal of high level radioactive waste is a challenging task facing the scientific and technical world.This paper introduces the latest progress of high level radioactive disposal programs in the worl... The geological disposal of high level radioactive waste is a challenging task facing the scientific and technical world.This paper introduces the latest progress of high level radioactive disposal programs in the world,and discusses the following key scientific challenges:(1)precise prediction of the evolution of a repository site;(2)characteristics of deep geological environment;(3)behaviour of deep rock mass,groundwater and engineering material under coupled conditions(intermediate to high temperature,geostress,hydraulic,chemical,biological and radiation process,etc);(4)geochemical behaviour of transuranic radionuclides with low concentration and its migration with groundwater;and(5)safety assessment of disposal system.Several large-scale research projects and several hot topics related with high-level waste disposal are also introduced. 展开更多
关键词 high level RADIOACTIVE WASTE GEOLOGICAL DISPOSAL UNDERGROUND research laboratory
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High-level radioactive waste disposal in China: update 2010 被引量:39
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作者 Ju Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE 2010年第1期1-11,共11页
For geological disposal of high-level radioactive waste (HLW), the Chinese policy is that the spent nuclear fuel (SNF) should be reprocessed first, followed by vitrification and final disposal. The preliminary rep... For geological disposal of high-level radioactive waste (HLW), the Chinese policy is that the spent nuclear fuel (SNF) should be reprocessed first, followed by vitrification and final disposal. The preliminary repository concept is a shaft-tunnel model, located in saturated zones in granite, while the final waste form for disposal is vitrified high-level radioactive waste. In 2006, the government published a long-term research and development (R&D) plan for geological disposal of high-level radioactive waste. The program consists of three steps: (1) laboratory studies and site selection for a HLW repository (2006-2020); (2) underground in-situ tests (2021-2040); and (3) repository construction (2041-2050) followed by operation. With the support of China Atomic Energy Authority, comprehensive studies are underway and some progresses are made. The site characterization, including deep borehole drilling, has been performed at the most potential Beishan site in Gansu Province, Northwestern China. The data from geological and hydrogeological investigations, in-situ stress and permeability measurements of rock mass are presented in this paper. Engineered barrier studies are concentrated on the Gaomiaozi bentonite. A mock-up facility, which is used to study the thermo-hydro-mechano-chemical (THMC) properties of the bentonite, is under construction. Several projects on mechanical properties of Beishan granite are also underway. The key scientific challenges faced with HLW disposal are also discussed. 展开更多
关键词 geological disposal high-level radioactive waste R&D program site selection BENTONITE
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Behavior Simulation of High Level Radioactive waste Repository in Beishan Granite Site
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作者 Weiming Chen,Ju Wang,Rui Su Beijing Research Institute of Uranium Geology,Beijing 100029,China. 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期187-187,共1页
This paper presents the behavior simulation of high level radioactive waste repository in Beishan granite site which is the most potential one in China.Based on the results from site characterization in Beishan granit... This paper presents the behavior simulation of high level radioactive waste repository in Beishan granite site which is the most potential one in China.Based on the results from site characterization in Beishan granite site,the conceptual model of repository in this site is proposed and its calculation model is developed with software GoldSim.After verification,this calculation model is applied to simulate the 展开更多
关键词 BEHAVIOR simulation high level RADIOACTIVE WASTE REPOSITORY Beishan
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Thermal Ionization Mass Spectrometry (TIMS)-U-Series Ages of Corals from the South China Sea and Holocene High Sea Level 被引量:9
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作者 彭子成 何学贤 +3 位作者 罗晓忠 贺剑峰 刘桂建 聂宝符 《Chinese Journal Of Geochemistry》 EI CAS 2003年第2期133-139,共7页
Coral samples collected from the waters off the Leizhou Peninsula, the Hainan Island and the Yongxing Island of the Xisha Islands were analyzed by thermal ionization mass spectrometry (TIMS) and multi-collector induct... Coral samples collected from the waters off the Leizhou Peninsula, the Hainan Island and the Yongxing Island of the Xisha Islands were analyzed by thermal ionization mass spectrometry (TIMS) and multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) for their U-Th systematics. Their uranium contents are mostly lower than 3μg/g, and the δ+{234}U(T) values are within the range of 150±5. X-ray diffraction analysis showed that the corals are all composed of aragonite. This demonstrates that the corals determined have maintained a close system for 7000 years and their skeletons bear much information about the primitive tropical marine environment. The highly precise age sequence of the corals determined has revealed that there occurred three phases of high sea level in the South China Sea waters, which are dated at 6799-6307 a B.P., 4472-4285 a B.P. and 1279-1012 a B.P., respectively. The three phases lasted 492 a, 187 a and 267 a, respectively. These three phases of high sea level are corresponding to the warm environments that had appeared in China during the Megathermal Period and the Medieval Warm Period in the past ten thousand years. 展开更多
关键词 南海 珊瑚虫 全新世 热致电离质谱测定法 雷州半岛 海南岛 地质年代学 古气候 古环境
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The Beishan underground research laboratory for geological disposal of high-level radioactive waste in China:Planning, site selection,site characterization and in situ tests 被引量:76
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作者 Ju Wang Liang Chen +1 位作者 Rui Su Xingguang Zhao 《Journal of Rock Mechanics and Geotechnical Engineering》 CSCD 2018年第3期411-435,共25页
With the rapid development of nuclear power in China, the disposal of high-level radioactive waste(HLW) has become an important issue for nuclear safety and environmental protection. Deep geological disposal is inte... With the rapid development of nuclear power in China, the disposal of high-level radioactive waste(HLW) has become an important issue for nuclear safety and environmental protection. Deep geological disposal is internationally accepted as a feasible and safe way to dispose of HLW, and underground research laboratories(URLs) play an important and multi-faceted role in the development of HLW repositories. This paper introduces the overall planning and the latest progress for China's URL. On the basis of the proposed strategy to build an area-specific URL in combination with a comprehensive evaluation of the site selection results obtained during the last 33 years, the Xinchang site in the Beishan area,located in Gansu Province of northwestern China, has been selected as the final site for China's first URL built in granite. In the process of characterizing the Xinchang URL site, a series of investigations,including borehole drilling,geological mapping, geophysical surveying,hydraulic testing and in situ stress measurements, has been conducted. The investigation results indicate that the geological,hydrogeological, engineering geological and geochemical conditions of the Xinchang site are very suitable for URL construction. Meanwhile, to validate and develop construction technologies for the Beishan URL, the Beishan exploration tunnel(BET), which is a 50-m-deep facility in the Jiujing sub-area, has been constructed and several in situ tests, such as drill-and-blast tests, characterization of the excavation damaged zone(EDZ), and long-term deformation monitoring of surrounding rocks, have been performed in the BET. The methodologies and technologies established in the BET will serve for URL construction.According to the achievements of the characterization of the URL site, a preliminary design of the URL with a maximum depth of 560 m is proposed and necessary in situ tests in the URL are planned. 展开更多
关键词 Beishan Xinchang site GRANITE Underground research laboratory(URL) high-level radioactive waste(HLW) Geological disposal
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Migration of Some Elements and Radionuclides across aGranite-Granite Contact Zone: A Natural Analoguefor Safe Disposal of High-Level Radwastes 被引量:4
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作者 LUO Xingzhang MIN Maozhong +4 位作者 ZHANG Guanghui LI Xianguo YANG Zhe ZHAI Liying Zhu Deling 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1999年第4期418-428,共11页
Abstract Elements and natural radionuclides in the contact zone of two granites with different ages would migrate from one to the other because of the difference in their chemical contents and later water-rock interac... Abstract Elements and natural radionuclides in the contact zone of two granites with different ages would migrate from one to the other because of the difference in their chemical contents and later water-rock interactions. This migration could serve as an analogue for the near-field process of radwastes in a high-level radwaste deep geological disposal repository. 展开更多
关键词 high-level radwaste safe disposal granitic contact zone natural analogue
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Health concerns of veterans with high-level lower extremity amputations
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作者 Elahe Faraji Mostafa Allami +4 位作者 Nafiseh Feizollahi Amir Karimi Amir Yavari Mohammadreza Soroush Majid Moudi 《Military Medical Research》 SCIE CAS CSCD 2019年第2期117-127,共11页
Background: To identify health concerns of veterans with high-level lower extremity amputations.Methods: Through a cross-sectional study, general practitioners, an orthopedic specialist, psychologists, psychiatrists,p... Background: To identify health concerns of veterans with high-level lower extremity amputations.Methods: Through a cross-sectional study, general practitioners, an orthopedic specialist, psychologists, psychiatrists,physiotherapist and prosthetists examined 100 veterans using a short-form health-related quality of life questionnaire(SF-36) that assessed their ability to perform activities of daily living(ADL), instrumental activities of daily living(IADL) and life satisfaction(SWLS) after hip disarticulation or hemi-pelvectomy amputations. The assessment tool was designed to gather statistically useful information about their health needs.Results: The means of the Physical Component Summary(PCS), Mental Component Summary(MCS), SWLS, ADL and IADL were 48.58±29.6, 33.33±22.0, 19.30±7.7, 48.10±10.5 and 5.08±1.8, respectively. Somatization, depression, and anxiety were the most prevalent disorders;among the veterans who were visited by psychiatrists, 11.6% had a history of hospitalization in a psychiatry section, and 53.2% had a psychiatric visit. Regardless of their injury in battle, 34% of veterans were hospitalized. Hearing problems were common, and about four-fifths of the participants suffered from at least one orthopedic condition. Neuroma(49%) was the most common stump-related complication during orthopedic evaluations, though the prevalence of phantom pain was 81% during the pain assessment. A total of 87% of the participants had a history of wearing a prosthesis, but only 29% wore a prosthesis at the time of the present study.The Canadian-type of prosthesis was uncomfortable and not useful(27%) and excessively heavy(10%) according to the amputees.Conclusions: Understanding veterans’ characteristics and special needs are important to make sure that enough facilities and services are afforded to them. These findings emphasize the importance of paying close attention to different dimensions of health in veterans and can help health providers identify health needs and make regular assessments. 展开更多
关键词 War-related trauma high level lower EXTREMITY AMPUTATION HEALTH needs assessment
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