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慢性荨麻疹患者血清PAF、抗-CCD IgE水平变化及临床意义分析
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作者 李椅云 毕超 +2 位作者 梁艳华 廖子青 梁碧华 《中国卫生标准管理》 2024年第18期75-78,共4页
目的探讨慢性荨麻疹患者血清血小板活化因子(platelet activating factor,PAF)、抗交叉反应性糖类决定簇免疫球蛋白E(anti-cross reactive carbohydrate determinants immunoglobulin E,抗-CCD IgE)水平变化及临床意义,为临床诊断及病... 目的探讨慢性荨麻疹患者血清血小板活化因子(platelet activating factor,PAF)、抗交叉反应性糖类决定簇免疫球蛋白E(anti-cross reactive carbohydrate determinants immunoglobulin E,抗-CCD IgE)水平变化及临床意义,为临床诊断及病情程度、预后评估提供参考依据。方法选取2021年5月—2023年5月广州市皮肤病防治所收治的100例慢性荨麻疹患者,根据荨麻疹活动评分分为轻度组(n=41)、中度组(n=35)和重度组(n=24)。采集患者空腹静脉血,通过酶联免疫吸附法测定血清PAF水平,通过斑点免疫印迹法测定抗-CCD IgE、过敏原特异性免疫球蛋白E(specific immunoglobulin E,sIgE)。比较不同病情程度慢性荨麻疹患者血清PAF水平,分析慢性荨麻疹患者血清PAF水平与荨麻疹活动评分相关性,比较不同临床特征慢性荨麻疹患者抗-CCD IgE阳性率。结果中度组、重度组患者血清PAF水平高于轻度组,重度组患者血清PAF水平高于中度组,差异有统计学意义(P<0.05)。Pearson相关分析结果显示,慢性荨麻疹患者血清PAF水平与荨麻疹活动评分呈正相关性(r=0.491,P<0.001)。年龄≥45岁、重度病情、sIgE阳性患者抗-CCD IgE阳性率高于年龄<45岁、轻度病情、sIgE阴性患者,差异有统计学意义(P<0.05)。抗-CCD IgE阳性患者中过敏原阳性最高的为尘螨组合(66.67%),其次为蟑螂、螃蟹、普通豚草,分别为55.56%、44.44%和44.44%。结论慢性荨麻疹患者血清PAF水平与病情密切相关,且抗-CCD IgE水平与sIgE水平有一定关系,抗-CCD IgE阳性表达情况对sIgE试验存在一定干扰,分析试验结果时应考虑抗-CCD IgE的影响。 展开更多
关键词 慢性荨麻疹 抗交叉反应性糖类决定簇免疫球蛋白e 血小板活化因子 免疫球蛋白e 水平变化 临床意义
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考虑减排潜力的中国省域碳排放权分配研究——基于改进的ZSG-DEA模型
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作者 钱昭英 田磊 《工业技术经济》 CSSCI 北大核心 2024年第7期91-100,共10页
在2030年中国实现碳达峰的目标背景下,本文针对碳排放权合理分配的问题,采用改进的ZSG-DEA模型考虑各省(区、市)的减排潜力,探寻兼顾公平和效率的碳排放权省域分配方案。研究结果表明:(1)我国各区域减排潜力各不相同,东部地区减排潜力较... 在2030年中国实现碳达峰的目标背景下,本文针对碳排放权合理分配的问题,采用改进的ZSG-DEA模型考虑各省(区、市)的减排潜力,探寻兼顾公平和效率的碳排放权省域分配方案。研究结果表明:(1)我国各区域减排潜力各不相同,东部地区减排潜力较大,西部地区减排潜力组内差距较大,且低减排潜力组有50%集中在西部地区,中部地区整体减排潜力不足,东北地区集中于中、低减排潜力组;(2)改进的ZSG-DEA模型计算出减排系数更加合理,缩减了减排压力差距,能通过缩小省(区、市)之间的不公平程度来降低政策实施难度;(3)综合减排潜力和减排系数两个方面发现,仍有部分省(区、市)如河南等处于低潜力高减排的状态,面临凭借自身条件难以有效降碳的困境,也有部分地区在碳减排方面“仍有余力”。基于上述结论,本文提出以下建议:各区域应发挥自身优势助力碳减排,在安排省(区、市)碳排放额度时要注重不同省(区、市)的减排潜力,同时加强减排责任意识,推动区域之间的合作。 展开更多
关键词 碳排放权分配 ZSG-DeA模型 减排潜力 减排压力 减排系数 区域异质性 公平 效率
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First-round design of the flight scenario for Chang’e-2’s extended mission:take off from lunar orbit 被引量:8
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作者 Yang Gao Heng-Nian Li Sheng-Mao He 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2012年第5期1466-1478,共13页
Chang'e-2, Chinese second lunar probe, was inserted into a 100 km altitude low lunar orbit on October 9th, 2010, its purpose is to continuously photograph the lunar surface and possibly chosen landing sites for futur... Chang'e-2, Chinese second lunar probe, was inserted into a 100 km altitude low lunar orbit on October 9th, 2010, its purpose is to continuously photograph the lunar surface and possibly chosen landing sites for future lunar missions. The probe will still carry considerable amount of propellant after completing all prescribed tasks in about six months. After the successful launch of Chang'e-2, we began designing the probe's subsequent flight scenario, considering a total impulse of 1 100 m/s for takeoff from low lunar orbit and a maximum 3× 10^6 km distance for Earth-probe telecom- munication. Our first-round effort proposed a preliminary flight scenario that involves consecutive arrivals at the halo orbits around the Earth-Moon L1/L2 and Sun-Earth L1/L2 points, near-Earth asteroid flyby, Earth return, and lunar impact. The designed solution of Chang'e-2's subsequent flight scenario is a multi-segment flight trajectory that serves as a reference for making the final decision on Chang'e-2's extended mission, which is a flight to the Sun-Earth L2 point, and a possible scheme of lunar impact via Earth flyby after remaining at the Sun-Earth L2 point was also presented. The proposed flight trajectory, which possesses acceptable solution accuracy for mission analysis, is a novel design that effectively exploits the invariant manifolds in the circular restricted three-body problem and the patched-manifold-conic method. 展开更多
关键词 change-2 Lunar mission Lagrange point Invariant manifold Patched-manifold-conic method
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Lunar Penetrating Radar onboard the Chang'e-3 mission 被引量:15
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作者 Guang-You Fang Bin Zhou +11 位作者 Yi-Cai Ji Qun-Ying Zhang Shao-Xiang Shen Yu-Xi Li Hong-Fei Guan Chuan-Jun Tang Yun-Ze Gao Wei Lu Sheng-Bo Ye Hai-Dong Han Jin Zheng Shu-Zhi Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第12期1607-1622,共16页
Lunar Penetrating Radar (LPR) is one of the important scientific instru- ments onboard the Chang'e-3 spacecraft. Its scientific goals are the mapping of lunar regolith and detection of subsurface geologic structure... Lunar Penetrating Radar (LPR) is one of the important scientific instru- ments onboard the Chang'e-3 spacecraft. Its scientific goals are the mapping of lunar regolith and detection of subsurface geologic structures. This paper describes the goals of the mission, as well as the basic principles, design, composition and achievements of the LPR. Finally, experiments on a glacier and the lunar surface are analyzed. 展开更多
关键词 change-3 mission -- moon rover -- Lunar Penetrating Radar
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Latest Scientific Results of China's Lunar and Deep Space Exploration(2022–2024)
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作者 XU Lin LI Lei +8 位作者 LIU Jianzhong LIN Honglei LI Yang LIU Yang XIE Lianghai ZHANG Jinhai QIAO Fuhao HAN Juanjuan ZOU Yongliao 《空间科学学报》 CAS CSCD 北大核心 2024年第4期622-632,共11页
China has successfully launched six lunar probes so far.From Chang'E-1 to Chang'E-4,they completed the circling,landing and roving exploration,of which Chang'E-4 was the first landing on the far side of th... China has successfully launched six lunar probes so far.From Chang'E-1 to Chang'E-4,they completed the circling,landing and roving exploration,of which Chang'E-4 was the first landing on the far side of the Moon in human history.Chang'E-5 was launched in December 2020,bringing back 1731 g of lunar soil samples.Through the detailed analysis of the samples,the scientists understand the history of late lunar volcanism,specifically extending lunar volcanism by about 800 million to 1 billion years,and proposed possible mechanisms.In addition,there are many new understandings of space weathering such as meteorite impacts and solar wind radiation on the Moon.China's first Mars exploration mission Tianwen-1 was successfully launched in July 2021.Through the study of scientific data,a number of important scientific achievements have been made in the topography,water environment and shallow surface structure of Mars.This paper introduces the main scientific achievements of Chang'E-4,Chang'E-5 and Tianwen-1 in the past two years,excluding technical and engineering contents.Due to the large number of articles involved,this paper only introduces part of the results. 展开更多
关键词 Lunar and deep space exploration of China chang’e-4 mission chang’e-5 mission Tianwen-1 mission
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Correlation analysis of human papillomavirus E6/E7 mRNA detection with diagnosis,prognosis and recurrence risk in patients with cervical epithelioma
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作者 Ling-Li Zhang Ming-Yan Du +5 位作者 Xin Du Jie Duan Dong-Mei Yao Jing Jing Chun Feng Lin Song 《World Journal of Clinical Cases》 SCIE 2024年第20期4146-4153,共8页
BACKGROUND Cervical intraepithelial neoplasia(CIN)is an important precursor of cervical cancer.Early detection and treatment can reduce the incidence of cervical cancer.AIM To investigate the detection rate of human p... BACKGROUND Cervical intraepithelial neoplasia(CIN)is an important precursor of cervical cancer.Early detection and treatment can reduce the incidence of cervical cancer.AIM To investigate the detection rate of human papillomavirus(HPV)E6/E7 mRNA in cervical tissue of patients with different types of epithelial cell neoplasia(CIN)and its relationship with CIN progression and diagnosis.METHODS One hundred women with HPV infection detected by cervical exfoliation cytology between January 2022 and January 2023 were retrospectively selected.These patients were graded CIN based on colposcopy and cervical pathology.The positive expression rates of HPV E6/E7 mRNA and HPV[polymerase chain reaction(PCR)-reverse dot crossing]were compared among all groups.Patients with HPV E6/E7 mRNA expression in the grade 1 CIN group were followed up for 1 yr.The relationship between atypical squamous epithelium and high malignant epithelial neoplasia was investigated by univariate and multivariate analysis.RESULTS The diagnostic sensitivity,specificity,and sensitivity of PCR-reverse point hybrid ization technology for secondary CIN were 70.41%,70.66%,and 0.714,respectively.Sensitivity and specificity for secondary CIN were 752%and 7853%,respectively,the area under the curve value was 0.789.Logistic Multifactorial model analysis revealed that the HPV positive rates and the HPV E6/E7 mRNA positive rates were independent risk factors of CIN grade I(P<0.05).In CIN grade I patients with positive for HPV E6/E7 mRNA,in its orientation to grade CIN patients,in its orientation to grade CIN patients,at 69.2%,compared with patients negative for HPV E6/E7 mRNA(30.8%),significant difference(P<0.05).CONCLUSION HPV E6/E7 mRNA and HPV(PCR-reverse dot hybrid)positive expression have a close relationship with CINgrade disease progression and is an independent risk factor for high-grade CIN lesions. 展开更多
关键词 Cervical epithelial neoplasia Human papilloma change with virus e6/e7 mRNA Cervical cancer Correlation analysis
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STREAMLINING EFFORTS BRING CHANGES TO OFFICE MISSIONS (CONTINUED)
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《Bulletin of the Chinese Academy of Sciences》 1999年第3期195-197,共3页
The Bureau of High-Technology Research and Development (BHRD) BHRD is in charge of management for the research and; development activities in high-technology areas in CAS, including predicting the trends of high-techn... The Bureau of High-Technology Research and Development (BHRD) BHRD is in charge of management for the research and; development activities in high-technology areas in CAS, including predicting the trends of high-technology development in the light of the demands for technology which is strategic, forward- 展开更多
关键词 CAS STReAMLINING eFFORTS BRING changeS TO OFFICe missionS CONTINUeD high
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Duncan-Chang E-υ模型在ADINA软件中的开发与应用 被引量:3
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作者 陈志波 朱俊高 陈浩锋 《武汉理工大学学报(交通科学与工程版)》 2010年第6期1280-1283,1288,共5页
ADINA软件具有计算速度快、精度高和前后处理简单方便的优点,广泛应用于各类工程领域.然而,ADINA软件中没有岩土工程领域常用的Duncan-Chang模型.以土工数值分析中广泛应用的Duncan-Chang E-υ模型为例,介绍了ADINA软件中进行本构模型... ADINA软件具有计算速度快、精度高和前后处理简单方便的优点,广泛应用于各类工程领域.然而,ADINA软件中没有岩土工程领域常用的Duncan-Chang模型.以土工数值分析中广泛应用的Duncan-Chang E-υ模型为例,介绍了ADINA软件中进行本构模型二次开发的方法,并给出了模型开发的方法和步骤.基于ADINA软件,以Duncan-Chang E-υ模型对某土石坝工程填筑过程进行了三维有限元计算,根据计算成果对坝体竣工期位移变形规律进行了分析. 展开更多
关键词 ADINA DUNCAN-chang e-υ模型 二次开发 土石坝 三维有限元
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Biochemical changes in phenols,flavonoids,tannins,vitamin E,β-carotene and antioxidant activity during soaking of three white sorghum varieties 被引量:7
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作者 Abd El-Moneim MR Afify Hossam S El-Beltagi +1 位作者 Samiha M Abd El-Salam Azza A Omran 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2012年第3期203-209,共7页
Objective:To investigate the changes in total phenols,flavonoids,tannins,vitamin E, β-carotene and antioxidant activity during soaking of three white sorghum varieties.Methods: The changes in total phenols,total ilav... Objective:To investigate the changes in total phenols,flavonoids,tannins,vitamin E, β-carotene and antioxidant activity during soaking of three white sorghum varieties.Methods: The changes in total phenols,total ilavonoids,tannins,phenolic acids compounds,flavonoid components,vitamin E,P-carotene and antioxidant activity during soaking of sorghum grains were determined.Results:Total phenols,total flavonoids,tannins,vitamin E,P-carotene and antioxidant activity in raw sorghum were ranged from 109.21 to 116.70,45.91 to 54.69,1.39 to 21.79 mg/100 g,1.74 to 5.25,0.54 to 1.19 mg/kg and 21.72%to 27.69%and 25.29%to 31.97%,respectively. The above measured compounds were significantly decreased after soaking.p-Hydroxybenzoic acid,vanillic acid,syringic acid and cinnamic acid represent the major phenolic acids in Dorado variety.While ferulic acid,p-coumaric acid,gallic acid and caffeic acid represent the major phenolic acids in Shandaweel-6.On the other hand,protocatechuic acid represents the major phenolic acids in Giza-15.Regarding flavonoids components,Dorado was the highest variety in kampferol and naringenin while Shandaweel-6 was the highest variety in luteolin, apigenin,hypersoid,quercelin and christen.Finally,Giza-15 was the highest variety in catechin. Phenolic acids,flavonoid compounds and antioxidant activities were decreased after soaking. Conclusions:Sorghum varieties have moderate quantities from total phenols,total flavonoids, tannins,phenolic acids compounds,flavonoid components,vitamin E,P-carotene and antioxidant activity which decreased after soaking. 展开更多
关键词 SORGHUM SOAKING Total PHeNOLS FLAVONOIDS TANNINS Vitamin e Β-CAROTeNe Antioxidant activity Phenolic acids Flavonoid components Biochemical change
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Vitamin E ameliorates aflatoxin-induced biochemical changes in the testis of mice 被引量:2
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作者 R.J.Verma Anita Nair 《Asian Journal of Andrology》 SCIE CAS CSCD 2001年第4期305-309,共5页
Aim: To assess the effect of aflatoxin on biochemical changes in the testis of mice and the possibility of ameliorationby vitamin E treatment. Methods: Adult male albino mice were orally administered with 25 or 50μg ... Aim: To assess the effect of aflatoxin on biochemical changes in the testis of mice and the possibility of ameliorationby vitamin E treatment. Methods: Adult male albino mice were orally administered with 25 or 50μg of aflatoxin/animal/day (750 or 1500 μg/kg body weight) for 45 days. The testis was isolated and processed for biochemical anal-ysis. Results; There was a significant, dose-dependent reduction in DNA, RNA, protein, sialic acid contents andthe activities of succinic dehydrogenase, adenosine triphosphatase and alkaline phosphatase in the testis of aflatoxin-treated mice as compared to the vehicle control. However, the acid phosphatase activity was significantly increased inthe aflatoxin-treated mice. Vitamin E (2 mg/animal/day) treatment significantly ameliorated the aflatoxin-inducedchanges, except the acid and alkaline phosphatase activities in the high dose group. Conclusion; Vitamin E treat-ment ameliorates the aflatoxin-induced changes in the testis of mice. (Asian J Androl 2001 Dec; 3: 305 - 309) 展开更多
关键词 AFLATOXIN vitamin e TeSTIS biochemical changes
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Distribution Prediction of Suitable Growth Area for Eucommia ulmoides in China under Climatic Change Background 被引量:3
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作者 Yang Liu 《Meteorological and Environmental Research》 CAS 2013年第8期21-24,共4页
[ Objective] The research aimed to study distribution prediction of suitable growth area for Eucommia ulmoides in China under climatic change background. [ Method] By using the maximum entropy model and many kinds of ... [ Objective] The research aimed to study distribution prediction of suitable growth area for Eucommia ulmoides in China under climatic change background. [ Method] By using the maximum entropy model and many kinds of climate change scenarios, we predicted current and future distribution pattems of suitable growth area for Eucommia ulmoides in China and its change process. [ Result ] At present, highly suitable growth area of E. ulmoides mainly distributed in Sichuan, Shaanxi and Chongqing, Under climate change background, total suitable growth areas in future three decades all drastically reduced when compared with that at present. It was noteworthy that moderately and highly suitable growth areas of wild E. ulmoides all disappeared, and junction between Shaanxi and Gansu and Taibai Mountain would be stable suitable growth area of wild E. ulmoides. [ Condusioa] The research could provide useful reference data for investigation, protection and sustainable development of the wild E. ulmoides resources. 展开更多
关键词 e. ulmoides Suitable growth area Climate change The maximum entropy model Distribution prediction China
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Assessment of Ecological Risk to Land Use in Liaoning Province Based on Climate Change 被引量:3
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作者 SUN Yun-peng1,2 1. College of City and Environment,Liaoning Normal University,Dalian 116029,China 2. Tangshan Teachers College,Tangshan 063000,China 《Asian Agricultural Research》 2010年第4期47-51,56,共6页
Based on the climatic data and other statistics of climatic data of 54 meteorological stations from 1956 to 2005 in Liangning Province,the annual and seasonal light,heat and water and the like major elements of climat... Based on the climatic data and other statistics of climatic data of 54 meteorological stations from 1956 to 2005 in Liangning Province,the annual and seasonal light,heat and water and the like major elements of climatic resources are diagnosed and analyzed by using the method of linear climate trend rate. The results show that warming trend is 0.25 ℃/10 a,the precipitation decrease gradually by 2.2 mm/a and the decreasing trend of solar radiation and hours of sunshine is not dramatic. The overall climate change trend is warming and drying,featuring "significantly increased temperature,the decreased precipitation and sunshine". These features are significant in autumn,thus leading to the trend of moving west and retreating east of the phenology boundaries. The results of scenario analysis on ecological security show that the ecological risk is spreading rapidly from the northwest to the east and to the south and form the southeastern and southern coastal line to the inland;different ecological land-use system have different ecological fragility. Specifically,the bare land and low coverage grassland have highest ecological vulnerability,while the forest and paddy filed have lowest ecological vulnerability. Therefore,suggestions on the ecological land use are put forward in terms of maintaining the overall ecological land use balance,saving water and adapting to climate change. 展开更多
关键词 Global CLIMATe change LAND use SCeNARIO analysis e
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Effect of Decadal Changes in Air-Sea Interaction on the Climate Mean State over the Tropical Pacific 被引量:3
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作者 FANG Xiang-Hui ZHENG Fei 《Atmospheric and Oceanic Science Letters》 CSCD 2014年第5期400-405,共6页
Collaboration of interannual variabilities and the climate mean state determines the type of E1 Nifio. Recent studies highlight the impact of a La Nifia-like mean state change, which acts to suppress the convection an... Collaboration of interannual variabilities and the climate mean state determines the type of E1 Nifio. Recent studies highlight the impact of a La Nifia-like mean state change, which acts to suppress the convection and low-level convergence over the central Pacific, on the predominance of central Pacific (CP) E1 Nifio in the most recent decade. However, how interannual variabilities affect the climate mean state has been less thoroughly investigated. Using a linear shallow-water model, the ef- fect of decadal changes of air-sea interaction on the two types of El Nifio and the climate mean state over the tropical Pacific is examined. It is demonstrated that the predominance of the eastem Pacific (EP) and CP E1 Nino is dominated mainly by relationships between anomalous wind stresses and sea surface temperature (SST). Furthermore, changes between air-sea interactions from 1980-98 to 1999-2011 prompted the generation of the La Ninalike pattern, which is similar to the background change in the most recent decade. 展开更多
关键词 air-sea interaction eP e1 Nifio CP e1 Nifio La Nina-like mean state change
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基于改进响应面的邓肯-张E-B模型参数全局敏感性分析 被引量:2
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作者 冯亚新 江兆强 +7 位作者 孙一清 王润英 沈振中 徐力群 甘磊 李皓璇 刘源 桂靖鹏 《水利水电科技进展》 CSCD 北大核心 2023年第2期44-50,81,共8页
为研究邓肯-张E-B模型参数及参数之间的交互作用对大坝变形的影响,以某均质黄土坝为研究对象,利用改进的响应面方法分析了邓肯-张E-B模型参数的全局敏感性。通过部分因子设计筛选出对土坝变形影响较为显著的5个参数为R_(f)、γ、φ_(0)... 为研究邓肯-张E-B模型参数及参数之间的交互作用对大坝变形的影响,以某均质黄土坝为研究对象,利用改进的响应面方法分析了邓肯-张E-B模型参数的全局敏感性。通过部分因子设计筛选出对土坝变形影响较为显著的5个参数为R_(f)、γ、φ_(0)、K_(b)、K,再利用响应面方法中的中心复合设计对筛选结果做进一步的全局响应面分析,考察参数及参数之间的交互作用对土坝变形的影响。结果表明,R_(f)、γ、φ_(0)是对大坝位移敏感性最强的3个参数,这3个参数之间的交互作用对于大坝变形的敏感性同样重要,且高于单个因素的敏感性,在类似工程计算中应考虑参数之间的交互作用。 展开更多
关键词 邓肯-张e-B模型 均质黄土坝 部分因子设计 中心复合设计 全局敏感性分析
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Response of fuzzy clustering on different threshold determination algorithms in spectral change vector analysis over Western Himalaya, India 被引量:2
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作者 SINGH Sartajvir TALWAR Rajneesh 《Journal of Mountain Science》 SCIE CSCD 2017年第7期1391-1404,共14页
Abstract: Change detection is a standard tool to extract and analyze the earth's surface features from remotely sensed data. Among the different change detection techniques, change vector analysis (CVA) have an ex... Abstract: Change detection is a standard tool to extract and analyze the earth's surface features from remotely sensed data. Among the different change detection techniques, change vector analysis (CVA) have an exceptional advantage of discriminating change in terms of change magnitude and vector direction from multispectral bands. The estimation of precise threshold is one of the most crucial task in CVA to separate the change pixels from unchanged pixels because overall assessment of change detection method is highly dependent on selected threshold value. In recent years, integration of fuzzy clustering and remotely sensed data have become appropriate and realistic choice for change detection applications. The novelty of the proposed model lies within use of fuzzy maximum likelihood classification (FMLC) as fuzzy clustering in CVA. The FMLC based CVA is implemented using diverse threshold determination algorithms such as double-window flexible pace search (DFPS), interactive trial and error (T&E), and 3x3-pixel kernel window (PKW). Unlike existing CVA techniques, addition of fuzzy clustering in CVA permits each pixel to have multiple class categories and offers ease in threshold determination process. In present work, the comparative analysis has highlighted the performance of FMLC based CVA overimproved SCVA both in terms of accuracy assessment and operational complexity. Among all the examined threshold searching algorithms, FMLC based CVA using DFPS algorithm is found to be the most efficient method. 展开更多
关键词 change vector analysis (CVA) Fuzzymaximum likelihood classification (FMLC) Double-window flexible pace search (DFPS) Interactive trialand error (T&e Pixel kernel window (PKW)
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Biochemical and Morphological Changes in the Lenses of Selenium and/or Vitamin E Deficient Rats 被引量:1
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作者 CAI QIU-YIN CHEN XIAO-SHU +7 位作者 ZHU LIAN-ZHEN XUE AN-NA LI WEN-XIAN WANG SHU-QIN PIAO JIAN-HUA LI JIE SUN CUN-PU WU KE AND CONG JIAN-BO(Institute of Nutrition and Food Hygiene, Chinese Academy of Preventive Medicine, 29 Nan Wet Road, Beijing 100050, Chin 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1994年第2期109-115,共7页
The activities of glutathione peroxidase (GSH-Px), glutathione reductase (GSSG-R),superoalde dismutase (SOD) and the contents of malondialdehyde (MDA) and free radicals were measured, and the morphological changes wer... The activities of glutathione peroxidase (GSH-Px), glutathione reductase (GSSG-R),superoalde dismutase (SOD) and the contents of malondialdehyde (MDA) and free radicals were measured, and the morphological changes were observed in the lens of control rats, selenium-deficient (SeD) and/or vitamin E deficient (VED) rats. The activities of GSH-Px in the lens of SeD rats decreased significantly. The GSH-Px activities of lens were positively related to erythrocytes selenium level. There was a free radical at g = 2.0015 in the rat lens of all groupe, but the content of free radicals in the lens of SeD group was significantly higher than that of the control group. The free radical content of lens was negatively related to erythrocytes selenium level, as well as the GSH-Px activities in the lens. In vitro, ultraviolet radiation caused the generation of another kind of free radical (g = 2.0097) in the lens of all groups, but the amount of the free radical in the lens of the SeD group was also significantly higher than that of the control group. The activities of SoD and GSSG-R in VED rat lens were significantly decreased. The amount of MDA in the lens of SeD and/or VED rats were significantly increased. The results showed that the decrease of antioaldative capability in the lenses of SeD and/or VED rats accelerated the lipid peroxidation and generation of free radicals. Although only early morphological changes in SeD and/or VED rat lens were observed, it is considered that selenium and vitamin E deficiency may be involved in the occurrence of cataract 展开更多
关键词 ReS GSH Biochemical and Morphological changes in the Lenses of Selenium and/or Vitamin e Deficient Rats
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Chang'e 4 Lands at the Far Side of the Moon 被引量:1
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作者 CAI Jinman 《Aerospace China》 2018年第4期63-63,共1页
Chang’e 4 began its travel to the moon at 02:23 Beijing time on December 8,2018 atop a LM-3B launch vehicle from the Xichang Satellite Launch Center.After separated from the carrier rocket,Chang’e 4 entered the Eart... Chang’e 4 began its travel to the moon at 02:23 Beijing time on December 8,2018 atop a LM-3B launch vehicle from the Xichang Satellite Launch Center.After separated from the carrier rocket,Chang’e 4 entered the Earth-moon transfer orbit with perigee of 200 km and apogee of 420 000 km. 展开更多
关键词 chang’e Lands MOON
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Historical Satellite Data Analysis to Enhance Climate Change Adaption and Hydrologic Models in Egypt
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作者 Mariam G. Salem Eman A. H. El-Sayed 《Journal of Power and Energy Engineering》 2017年第8期56-71,共16页
Egypt suffers from the impacts of climate change. Adaption plans should solve the shortage in water resources and increase the use of renewable energy. Detailed data on rainfall as non conventional water and detailed ... Egypt suffers from the impacts of climate change. Adaption plans should solve the shortage in water resources and increase the use of renewable energy. Detailed data on rainfall as non conventional water and detailed data on potential renewable energy are important. The added value of this research is to investigate the suitability of satellite data locally in North Sinai in Egypt. The Tropical Rainfall Measuring Mission (TRMM) satellites and available data from ground rain gauges are studied at North Sinai of Egypt. Local multiplication factors and correlation equations on a monthly basis were developed based on short term historical data. General equation based on short term data was developed to enhance TRMM data for the rainy season to minimize spatial and temporal errors. This equation would be very useful, especially in the ungauged areas in North Sinai to adjust TRMM rainfall data. TRMM data are spatially distributed, so it enhances the hydrology models for runoff estimation. This runoff could be used as non conventional water resource. The runoff was estimated in the RasSudr area in the 2010 storm to be 3.6 (m3/s). The hydropower of this runoff was estimated and ranged from 15,135 to 57,352 (kWh). The solar energy is studied from (NASA) satellite data. The monthly averaged solar energy was estimated to get possible generated power from the solar panel at locations of rainfall ground stations. The generated solar energy would supply self-sufficient energy for ground stations measuring instruments rather than batteries. The results show that a small solar panel project of 200 (m2) could safe electric network power by generating about 20,385 (kWh/year). The results of this study could help in enhancing adapting plans for climate change and runoff estimation model that needs grid data, especially in the area lacking ground data. 展开更多
关键词 TROPICAL RAINFALL Measuring mission Data Analysis Hydrologic Model Bias Factor ReNeWABLe Power Generation Climate change RS GIS
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Mission(美声)e82家庭影院系统
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《视听技术》 2004年第12期57-57,共1页
英国著名的扬声器制造厂HiSSion最近推出的Eiegante“典雅”系列音箱,以套件形式向需要高级家庭影院的用家提供了理想的解决方案。“典雅”系列音箱的外观造型源于Mission旗舰音箱Pilastro,流线型的箱体造型以及略微朝前倾斜的箱顶具... 英国著名的扬声器制造厂HiSSion最近推出的Eiegante“典雅”系列音箱,以套件形式向需要高级家庭影院的用家提供了理想的解决方案。“典雅”系列音箱的外观造型源于Mission旗舰音箱Pilastro,流线型的箱体造型以及略微朝前倾斜的箱顶具有帮助声音扩散并且消除边角反射波之功效。“典雅”系列目前包含e83、e82和e80三套系统,e82是其中的老二。e82系统具体由2只高挑的e82落地箱、3只e80书架箱和1只e8c中置音箱组成,当然还少不了输出强劲的有源重低音e8aS1。 展开更多
关键词 mission公司 e82 家庭影院 性能
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Eastern Siberia permafrost transect(ESPT).A first stage:The Verkhoyansk Range part
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作者 Robert SYSOLYATIN Svetlana KALINICHEVA +1 位作者 Alexander FEDOROV Maria ROZHINA 《Journal of Mountain Science》 SCIE CSCD 2023年第6期1499-1507,共9页
Environmental and geomorphological processes in the mountainous areas of Eastern Siberia is strongly conditioned by the thermal state of permafrost(permanently frozen ground).However,the scarce data about climate and ... Environmental and geomorphological processes in the mountainous areas of Eastern Siberia is strongly conditioned by the thermal state of permafrost(permanently frozen ground).However,the scarce data about climate and weak of permafrost study have led to the unclarity of mountain permafrost condition in this region.The increase in the mean annual air temperature over the past 50 years in the northeastern Siberia by various estimates is from 1.1℃to 3.3℃.So far,almost no information is available on the permafrost response to climatic changes in the region.The Kolyma Route(around 2000 km length),connecting Yakutsk and Magadan that crosses 5 climatic types and more than 10 permafrost landscapes,so it seems a suitable path for establishing basic(reference)monitoring sites.From 12 target boreholes,on the first stage 5 boreholes up to 30 m in depth were drilled and instrumented for measuring temperature at sites adjacent to weather stations in the Verkhoyansk Range from 283 to 1288 m a.s.l.Here we present conception,purpose,and methods for permafrost study project with first preliminary results from the highest weather station of the East Siberia Mountain.The following research about geophysical investigations,permafrost landscape description,mapping and spatial modelling,numerical computing,physical modelling of permafrost thickness might be initiated by the Eastern Siberia Permafrost Transect(ESPT)-project. 展开更多
关键词 Ground temperature Mountain permafrost Temperature e monitoring Verkhoyansk Range Climate change.
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