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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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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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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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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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Chang'e 3 Lander Completed Mechanical Test
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《Aerospace China》 2012年第4期23-23,共1页
Aground firing test of the Chang'e 3 lander was conducted recently to check the mechanical performance of the spacecraft. The test was vital before the propulsion system test of the Chang'e 3 lander and was al... Aground firing test of the Chang'e 3 lander was conducted recently to check the mechanical performance of the spacecraft. The test was vital before the propulsion system test of the Chang'e 3 lander and was also a very important precondition to verify whether the propulsion system design could meet the requirements for in-orbit operation. 展开更多
关键词 TeST very chang’e 3 Lander Completed Mechanical Test
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Factors for the Major Changes in the English Language
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作者 Lu Ling, Dept of Foreign Languages, Fuyang Teachers College, Fuyang 236032 《阜阳师范学院学报(社会科学版)》 2001年第1期42-44,共3页
本文阐述了引起英语变迁的历史因素-罗马人,条顿人,诺尔曼人的四次入侵;以及音变因素-e音的丢失和元音大转移。此外,印刷业的发展加速了拼写的标准化,十六、十七世纪英国文艺复兴极大地丰富了英语词汇。
关键词 英语拼写 语言变迁 历史 音变 e 元音 文艺复兴 英语 词汇 印刷业 侵略 罗马人 条顿人 诺尔曼人
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Chang'e 5 Undergoing Thermal Test
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作者 QI Guangming LI Zhenwei CAI Xiaomao 《Aerospace China》 2017年第1期59-59,共1页
Chang’e 5 probe has entered its critical phase of AIT.Units,except the lander,are undergoing thermal test.The flight model of Chang’e 5 is composed of an orbiter,a return capsule,a lander and an ascent unit.The ther... Chang’e 5 probe has entered its critical phase of AIT.Units,except the lander,are undergoing thermal test.The flight model of Chang’e 5 is composed of an orbiter,a return capsule,a lander and an ascent unit.The thermal tests on the ascent unit,the lander-as- 展开更多
关键词 TeST chang’e 5 Undergoing Thermal Test
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月球样品的中子活化分析技术研究 被引量:6
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作者 姚永刚 肖才锦 +4 位作者 李玉庆 焦学胜 孙凯 郭冰 陈东风 《中国无机分析化学》 CAS 北大核心 2024年第1期93-103,共11页
月球的起源是月球研究的核心问题。月球探测任务返回的数据和样品极大地提高了人类对地月系统的认知,同时也发现了更多未解之谜,亟待未来的探测任务和科学研究来解答。嫦娥五号月壤是我国首次地外天体采集返回的样品,也是继美国和苏联... 月球的起源是月球研究的核心问题。月球探测任务返回的数据和样品极大地提高了人类对地月系统的认知,同时也发现了更多未解之谜,亟待未来的探测任务和科学研究来解答。嫦娥五号月壤是我国首次地外天体采集返回的样品,也是继美国和苏联探月采样任务45年后人类再次获得的月球样品。鉴于月球样品的珍贵性和特殊性,利用先进技术开展其全元素含量的非破坏精准分析对于认识月球演化和月球资源就地开发利用具有重要的意义。依托大型核反应研究堆和加速器中子注量率优势,利用中子活化分析技术可实现月球样品中的全元素非破坏分析:1)仪器中子活化分析技术(INAA)可测量Na—U元素之间的60余种元素;2)瞬发γ中子活化分析技术(PGNAA)可补充测量INAA不适合测量的元素如H、B、C、N等;3)中子深度剖面分析技术(NDP)可测量样品近表面(微米级)聚变能源3He的浓度深度分布;4)缓发中子测量技术(DNC)可定量样品中痕量裂变核素如^(235)U和^(239)Pu,并结合INAA可测量238U/235U同位素比值;5)14 MeV快中子活化分析技术(FNAA)可测量INAA和PGNAA不灵敏或不适合测量的元素如O、Si、P等。因此,中子活化分析技术(NAA)可有效解决月球样品中全元素、非破坏和精准测量问题,为我国深空探测珍贵样品研究提供核分析技术支撑。 展开更多
关键词 嫦娥五号月壤 月球陨石 中子活化分析 非破坏分析 深空探测
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人工智能时代的机遇与挑战——第18届远程教育与在线学习研究会议综述
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作者 蒋亦璐 牛阿娜 《世界教育信息》 2024年第7期73-80,共8页
在第18届远程教育与在线学习研究会议上,来自24个国家和地区的600多位与会者就新兴技术的应用、教育理论和方法的创新、在线学习评估、国际化与跨国教育、学生的归属感和幸福感、在线协作学习等主题的120多项最新学术研究展开深入交流... 在第18届远程教育与在线学习研究会议上,来自24个国家和地区的600多位与会者就新兴技术的应用、教育理论和方法的创新、在线学习评估、国际化与跨国教育、学生的归属感和幸福感、在线协作学习等主题的120多项最新学术研究展开深入交流。专家立足远程教育与在线学习方面的理论和实践创新,对如何应对人工智能时代的机遇和挑战形成一定共识:一是人工智能等新兴技术正在重塑教育形态,二是推进教学理论与方法创新以助力人机协作,三是创设包容友好的学习环境和改善学习体验,四是灵活的教育形式可以改善资源不足和质量不均。 展开更多
关键词 远程教育 在线学习 教育模式变革 教育技术应用 个性化学习 智能教育
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冷季深入对AMSR-E监测内蒙古积雪的影响 被引量:7
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作者 袁雷 李春娥 +2 位作者 储少林 严建武 陈全功 《草业科学》 CAS CSCD 2008年第8期26-30,共5页
传统的积雪范围和厚度监测是通过气象台站的定时观测,其缺点是:地面观测资料区域代表性有限和地面气象台站分布很均匀。遥感技术可以弥补传统观测的不足,中分辨率成像光谱仪(Moderate Resolution Imaging Spectroradiometer,MODIS)数据... 传统的积雪范围和厚度监测是通过气象台站的定时观测,其缺点是:地面观测资料区域代表性有限和地面气象台站分布很均匀。遥感技术可以弥补传统观测的不足,中分辨率成像光谱仪(Moderate Resolution Imaging Spectroradiometer,MODIS)数据具有高空间分辨率、高时间分辨率,地球观测系统先进微波扫描辐射计(Advanced Microwave Scanning Radiometer-EOS,AMSR-E)数据具有不受云层影响的特点。分析冷季深入对AMSR-E影像积雪判别的影响,最终得出,在内蒙古地区随着冷季的深入,AMSR-E将MODIS影像上无雪像元和有云像元判别为有雪的比例越来越高,最高分别达34.22%和28.29%。两者同时判别为有雪像元的比例也越来越高,最高达33.66%。 展开更多
关键词 内蒙古 MODIS AMSR-e 季节变化
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基于CIM/E的配电网模型异动管理 被引量:11
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作者 钱静 崔立忠 +5 位作者 尚学伟 陈鑫 郝泽赟 高习斌 王玲 钱传伟 《电网技术》 EI CSCD 北大核心 2014年第12期3516-3521,共6页
配电自动化系统建模对外部系统依赖性强、信息源头多、形式多样、需要流程管理,因此带来了信息交互标准性、完整性、时效性差等问题,为此,提出基于CIM/E(高效模型描述规范语言)的配网模型异动管理方案。分析了CIM/E作为模型和模式数据... 配电自动化系统建模对外部系统依赖性强、信息源头多、形式多样、需要流程管理,因此带来了信息交互标准性、完整性、时效性差等问题,为此,提出基于CIM/E(高效模型描述规范语言)的配网模型异动管理方案。分析了CIM/E作为模型和模式数据描述语言的特点,以及应用在配网模型管理中的可行性和优势;探讨了CIM/E在模型导入、导出、模型抽取、异动分析、增量投退、版本管理技术上的具体运用;并提出以异动单为最小单元的配网模型异动管理方法。介绍了相关软件产品的实际用例,基于CIM/E和异动单的配网模型管理,可以部分解决配网信息集成准确性、时效性方面的问题,并可满足模型管理的原子性、完整性的需求。 展开更多
关键词 智能配电网 IeC 61970/61968标准 模型异动管理 CIM/e 异动单 信息集成
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