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Structural-Adaptation Features of Assimilation Organs of the Species Salsola incanescens Cam. in Conditions of Kyzylkum
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作者 Guli A. Ibrokhimova Guljan M. Duschanova 《American Journal of Plant Sciences》 CAS 2024年第7期589-602,共14页
The article presents the results of the morpho-anatomical structure of the assimilation organs of the species Salsola leptoclada Gand, which is widespread in the Kyzylkum desert region of Uzbekistan, and reveals the s... The article presents the results of the morpho-anatomical structure of the assimilation organs of the species Salsola leptoclada Gand, which is widespread in the Kyzylkum desert region of Uzbekistan, and reveals the structural, diagnostic and adaptive features. In the assimilation organs, Kranz type of mesophyll was found: in the cotyledons of the Kranz-spherical (Atriplicoid) type, and in the leaf—mesophylls of the Kranz-centric (Salsoloid) and Kranz-ventrodorsal type. These revealed diagnostic features of the assimilating organs of this species in arid conditions noted C4-type photosynthesis. Based on the comparative biometric analysis of quantitative indices of the anatomical features of the assimilating organs, xero-halomorphic features predominate. Halomorphic features are in the cotyledons—thin outer walls of the epidermal cells;few stomata of the anomocytic and paracytic type;few rows of spongy cells (3 - 4 rows);few vascular bundles of the collateral type and xylem, in the leaf—large and thin outer walls of the epidermal cells;succulence of the leaf mesophyll, the presence of aquiferous cells;large palisade, keratin and aquiferous cells. Xeromorphic features in the cotyledons—small and numerous epidermal cells and hemiparacytic type stomata also deep immersion;small palisade cells and a high palisade index, small spongy, hypodermal and keratin cells;small diameter of the xylem in vascular bundles;in the leaf numerous epidermal cells and stomata also deeply immersed;presence and numerous multicellular nodular, dentate trichomes;multi-row water-bearing cells;high palisade index;small and numerous xylem;numerous peripheral vascular bundles of the collateral type. These identified specific diagnostic features showing adaptation to arid conditions can also serve in the identification of plant materials. 展开更多
关键词 Morphology ANATOMY COTYLEDON LEAF Salsola incanescens south-west Kyzylkum
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南沙海槽—西北巴拉望构造特征及其意义
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作者 李学杰 汪俊 +2 位作者 王哲 姚永坚 祝嵩 《吉林大学学报(地球科学版)》 CAS CSCD 北大核心 2024年第4期1081-1094,共14页
南沙海槽-西北巴拉望构造对认识南海成因与演化至关重要。综合南海南缘地质地球物理资料分析认为:南沙海槽极薄地壳可能不是古南海的残余,是夭折的扩张中心;南沙海槽存在挤压逆冲作用,形成时间很晚,与南海扩张无关,是南海形成后挤压的... 南沙海槽-西北巴拉望构造对认识南海成因与演化至关重要。综合南海南缘地质地球物理资料分析认为:南沙海槽极薄地壳可能不是古南海的残余,是夭折的扩张中心;南沙海槽存在挤压逆冲作用,形成时间很晚,与南海扩张无关,是南海形成后挤压的结果。南沙海槽挤压作用与西北巴拉望Pagasa楔变形对比表明,南海南缘的挤压作用停止时间东部早于西部;中、南巴拉望蛇绿岩来自其南部往北逆冲的产物,可能表明古南海由南往北俯冲。综上认为南巴拉望蛇绿岩可能来自新特提斯洋壳,中巴拉望蛇绿岩来自古南海洋壳;不同时期洋壳俯冲残余最终被逆冲至岛弧系之上;巴拉望蛇绿岩是长期由南往北逆冲的结果,最后就位时间可能是中晚中新世。 展开更多
关键词 南海南缘 南沙海槽逆冲构造 古南海 巴拉望蛇绿岩
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Seroepidemiology of hepatitis C and its risk factors in Khuzestan Province, South-West of Iran:A case-control study 被引量:2
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作者 Eskandar Hajiani Jalal Hashemi +3 位作者 Rahim Masjedizadeh Ali Akbar Shayesteh Esmail Idani Tahereh Rajabi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第30期4884-4887,共4页
AIM:To evaluate possible risk factors for the spread of hepatitis C infection and to analyze the characteristics of the epidemiological and clinical patterns among the patients with hepatitis C infection. METHODS: D... AIM:To evaluate possible risk factors for the spread of hepatitis C infection and to analyze the characteristics of the epidemiological and clinical patterns among the patients with hepatitis C infection. METHODS: During a five-year period a cross-sectional study was conducted among HCV positive individuals referred to the Ahwaz JundiShapour University Hospitals (AJSUH) and Hepatitis Clinic from 1 Sept 1999 to 1 Sept 2003. The control group consisted of first time blood donors referred to the Regional Blood Transfusion organization. Enzyme-linked immunosorbent assay and recombinant immunoblot assay anti-hepatitis C virus (HCV) tests were performed for two groups. Positive serum specimens were retested using polymerase chain reaction (PCR) for HCV RNA. Risk factors were evaluated using a questionnaire. Reported risk factors among infected subjects ("HCV-positive") were compared to those of subjects never exposed ("HCV-negative") to HCV. RESULTS: A total of 514 subjects were studied for HCV, of which 254 were HCV-positive and 260 HCV- negative donors comprised the control group. Mean age of the patients was 28.4 (Std 15.22) years. HCV-positive subjects were more likely to be of male gender (63% versus 37%). Transfusion 132 (52%), non-intravenous (n-iv) drug abuse and iv drug abuse 37 (14.5%), haemodialysis 25 (10%), receiving wounds at war and extramarital sexual activities (2.4%), tattooing (3.6%) were found to be independent risk factors of being HCV-positive. No apparent risk factors could be demonstrated in 29 (11.2%) of the positive cases. CONCLUSION: Our data indicate that a history of transfusion and iv drug abuse and haemodialysis are important risk factors for HCV infection in our area and that more careful pretransfusion screening of blood for anti- HCV must be introduced in our blood banks. Improvements in certain lifestyle patterns, and customs in this area may be essential to prevent transmission of the infection. 展开更多
关键词 Epidemiological patterns Hepatitis C virus Risk factors south-west of Iran
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Resolution pattern of jaundice among children presenting with severe malaria in rural South-West Nigeria 被引量:1
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作者 Osonuga OA Osonuga A +1 位作者 Osonuga AA Osonuga IO 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2012年第7期551-553,共3页
Objective:To compare the pattern of jaundice resolution among children with severe malaria treated with quinine and artemether.Methods:Thirty two children who fulfilled the inclusion criteria were recruited for the st... Objective:To compare the pattern of jaundice resolution among children with severe malaria treated with quinine and artemether.Methods:Thirty two children who fulfilled the inclusion criteria were recruited for the study from two hospitals with intensive care facilities.They were divided into two groups:'Q' and 'A',receiving quinine and artemether.respectively.Jaundice was assessed by clinical examination.Results:Sixteen out of 32 children recruited(representing50%) presented with jaundice on the dav of recruitment.The mean age was(7.00±2.56) years.On day 3,tour patients in 'A' and six patients in 'O' had jaundice.By day 7.no child had jaundice.Conclusion:The study has shown that hoth drugs resolve jaundice although artemether relatively resolves it faster by the third day. 展开更多
关键词 JAUNDICE Quinine Artemether Severe malaria south-west NIGERIA
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Evaluation of forest disturbance in south-west Zabaikalia (East Siberia) 被引量:1
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作者 Т.А.MIKHAILOVA L.V.AFANASIEVA +1 位作者 O.V.KALUGINA О.V.SHERGINA 《Forestry Studies in China》 CAS 2013年第4期332-339,共8页
The forest estate in south-west Zabaikalia, a territory included in the Lake Baikal catchment area, has been investigated. For this purpose we have used both data of our own studies and monitoring data of environmenta... The forest estate in south-west Zabaikalia, a territory included in the Lake Baikal catchment area, has been investigated. For this purpose we have used both data of our own studies and monitoring data of environmental protection bodies. It shows that in our study area, fires, fellings, entomo-parasites and air pollution are the major negative factors affecting the state of the forest. In the period from 2003 to 2008 fires were registered in the area of over 500 thousand ha, pest foci in the forests covering an area of over 330 thousand ha, where almost 5 million m3wood was cut in an area of about 43 thousand ha. The total area of forests in our study affected by air pollution amounts to about 700 thousand ha. According to the results, forest pollution in the territory is concentrated in the vicinity of large-scale industrial complexes, for distances up to about 40 km. The total area of forests weakened by air pollution amounts to about 2 million ha. 展开更多
关键词 south-west Zabaikalia Lake Baikal catchment area forest state negative factors
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北-南巴拉望盆地油气地质特征及成藏条件
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作者 张厚和 刘世翔 +1 位作者 郝婧 宋双 《长江大学学报(自然科学版)》 2023年第4期16-22,共7页
基于前人区域研究成果与收集到的近年最新地震、钻井等资料,对北-南巴拉望盆地构造-沉积充填演化进行了研究,并进一步分析了北-南巴拉望盆地烃源岩、储集层和圈闭等油气地质特征和成藏条件。研究表明,北-南巴拉望盆地新生代经历了始新世... 基于前人区域研究成果与收集到的近年最新地震、钻井等资料,对北-南巴拉望盆地构造-沉积充填演化进行了研究,并进一步分析了北-南巴拉望盆地烃源岩、储集层和圈闭等油气地质特征和成藏条件。研究表明,北-南巴拉望盆地新生代经历了始新世-早渐新世裂陷期、晚渐新世-早中新世漂移期、中中新世前陆期及晚中新世-第四纪拗陷期4个构造演化阶段,其中始新世-早渐新世发育三角洲-滨浅海沉积体系,晚渐新世-早中新世发育碳酸盐岩台地-生物礁-滨浅海沉积体系,中中新世-第四纪发育三角洲-正常开阔海沉积体系。北-南巴拉望盆地发育始新统-下渐新统和上渐新统-下中新统2套烃源岩、下中新统碳酸盐岩和下中新统砂岩2类主要储层以及中中新统-第四系区域性盖层,发育生物礁和构造2类油气藏,具有“下生上储”和“自生自储”2类成藏模式。 展开更多
关键词 北-南巴拉望盆地 构造演化 沉积充填 油气地质特征 成藏条件
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Prevalence of hepatitis B virus infection and associated risk factors among adult females infected with Human Immunodeficiency Virus in Ogun State,Nigeria
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作者 John Cletus Ihongbe Seyi Samson Enitan +5 位作者 Michael Olugbamila Dada Oluchi Ofem Oluchi Gladys Ofem Effiong Joseph Effiong Olalekan Ademola Kemiki Amarachi Favour Ogbonna 《Infectious Diseases Research》 2023年第3期1-9,共9页
Background:Hepatitis B virus(HBV)infection is prevalent in sub-Saharan Africa,including Nigeria,and is frequently observed in individuals co-infected with human immunodeficiency virus(HIV).Objective:This study aims to... Background:Hepatitis B virus(HBV)infection is prevalent in sub-Saharan Africa,including Nigeria,and is frequently observed in individuals co-infected with human immunodeficiency virus(HIV).Objective:This study aims to evaluate the prevalence of serological markers for hepatitis B virus and identify the associated risk factors among women with HIV undergoing highly active antiretroviral therapy(HAART)in Ogun State,Nigeria.Methods:Ethical approval was obtained from the Babcock University Health Research Ethics Committee(BUHREC)to recruit a total of 110 adult women infected with HIV,receiving treatment at the HIV clinics of Babcock University Teaching Hospital(BUTH)in Ilishan-Remo and General Hospital in Ijebu-Ode,both located in Ogun State,Nigeria.The participants’HIV status were confirmed using three rapid diagnostic kits:Determine(Abbott Laboratories,Tokyo,Japan),Unigold HIV(Trinity Biotech Plc Bray,Co.Wicklow,Ireland),and 1/2 Stat Pak(Abbott Laboratories,Tokyo,Japan)(Chembio Diagnostic Systems,New York,USA).Additionally,an HBV 5 in 1 Panel manufactured by Innovation Biotechnology Co.,Ltd in Beijing,China,was employed to detect HBV markers qualitatively in serum samples.Results:Out of the 110 subjects that voluntarily participated in the study,4(3.6%)tested positive for HBsAg,2(1.8%)tested positive for HBsAb,81(73.6%)tested positive for HBeAg,3(2.7%)tested positive for HBeAb,and 65(59.1%)tested positive for HBcAb.There was no significant correlation between the occurrence of HBsAg and the socio-demographic characteristics of the participants(P>0.05).Various risk factors were identified,including lack of knowledge about HBV,absence of HBV vaccination history,history of blood transfusion,organ transplant,and engaging in unprotected sex,among others.Conclusion:The findings highlight the presence of HBV infection among HIV-positive women undergoing HAART in Ogun State,Nigeria,particularly within the age groups of 18–25 years and 26–30 years.These results emphasize the necessity for continuous and targeted public health interventions among this specific population. 展开更多
关键词 hepatitis B virus serological markers HIV HAART adult females south-west Nigeria
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南海及周边部分地区特提斯构造遗迹:问题与思考 被引量:14
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作者 颜佳新 周蒂 《热带海洋学报》 CAS CSCD 北大核心 2002年第2期43-49,共7页
对全球二叠纪──三叠纪古气候特征的研究表明,东特提斯地区晚三叠世古气候标志具有带状分布的特征。北巴拉望地块卡拉棉群岛科龙岛的晚三叠世沉积中发育反映较干燥古气候特征的鲕状灰岩,因此在古气候特征方面,北巴拉望地块晚三叠世... 对全球二叠纪──三叠纪古气候特征的研究表明,东特提斯地区晚三叠世古气候标志具有带状分布的特征。北巴拉望地块卡拉棉群岛科龙岛的晚三叠世沉积中发育反映较干燥古气候特征的鲕状灰岩,因此在古气候特征方面,北巴拉望地块晚三叠世地层不能与华南和印支地块同期地层对比,而应该与印度地块北缘喜马拉雅地区(向西)和琉球群岛(向东)对比。根据该古气候分析,北巴拉望地块在晚三叠世时应该位于南部亚热带较干燥气候带内,其晚三叠世的古地理位置比印支地块更靠南。对南海及南海周边部分地区特提斯构造遗迹的研究,将有助于深入了解南海北部陆缘区相关构造带的性质及正确恢复南海扩张之前该区的地质发展历史。南海北部陆缘区也是研究解决特提斯构造向东延伸问题以及特提斯构造-太平洋构造时空转化问题的关键地区。 展开更多
关键词 南海 北巴拉望地块 晚三叠世 特提斯构造遗迹 古气候 特提斯缝合成
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南海共轭被动大陆边缘洋陆转换带构造特征 被引量:9
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作者 高金尉 吴时国 +4 位作者 彭学超 董冬冬 范建柯 贾连凯 周金扬 《大地构造与成矿学》 EI CAS CSCD 北大核心 2015年第4期555-570,共16页
南海被动大陆边缘洋陆转换带与典型洋陆转换带相比有其特殊性,南海共轭被动陆缘的构造运动、火山活动以及海底地形的差异表明南、北洋陆转换带具有不同的构造特征。本文利用多条多道地震反射剖面和重力异常数据,研究南海共轭被动陆缘洋... 南海被动大陆边缘洋陆转换带与典型洋陆转换带相比有其特殊性,南海共轭被动陆缘的构造运动、火山活动以及海底地形的差异表明南、北洋陆转换带具有不同的构造特征。本文利用多条多道地震反射剖面和重力异常数据,研究南海共轭被动陆缘洋陆转换带构造特征差异性,探讨南海被动陆缘的类型和伸展模式。南海北部陆缘洋陆转换带可以划分为两种类型:一类以前缘铲状断块为界与洋壳区分,发育有裂陷期断陷、火山带(埋藏海山带)和不十分发育的向海倾的掀斜断块带;另一类则以海山为界,发育裂陷期断陷、宽缓的低凸起和火山或海山。深反射地震特征显示出了下地壳高速层的存在。南部以裂陷期断陷和明显的向海倾的掀斜断块为特征,以前缘铲式断层为界与洋壳区分。自由空间重力异常由陆向海从高异常值过渡为低异常值再到高异常值,预示着地壳由陆壳→过渡壳→洋壳的变化。结果表明,南海共轭被动陆缘更可能属于非火山型被动大陆边缘,其洋陆转换带的构造差异主要受岩石圈差异伸展变形控制。 展开更多
关键词 被动大陆边缘 洋陆转换带 珠江口盆地 西北巴拉望盆地-礼乐盆地 差异伸展
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夏季巴拉望岛西北部海域净热通量的时空变化特征和形成机理初析 被引量:1
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作者 田永青 潘爱军 《台湾海峡》 CAS CSCD 2012年第4期540-548,共9页
利用OAFLUX气候态月平均热通量资料及TMI云量、降雨、SST和QuikScat风场资料,对南海、特别是巴拉望岛西北海域净热通量的时空特征进行了深入分析.研究发现,夏季在巴拉望岛西北海域存在一局域净热通量极小值区,在7月份该海域海洋甚至呈... 利用OAFLUX气候态月平均热通量资料及TMI云量、降雨、SST和QuikScat风场资料,对南海、特别是巴拉望岛西北海域净热通量的时空特征进行了深入分析.研究发现,夏季在巴拉望岛西北海域存在一局域净热通量极小值区,在7月份该海域海洋甚至呈现失热达20 W/m2情况.分析认为该局地净热通量异常可能与南海暖水的发生、发展有关,即由于西南季风爆发,巴拉望岛西北海域对流加强,一方面,蒸发增大使得潜热增大、云量增多,导致入射太阳短波辐射的减少;另一方面,降水的增大使得该海域出现障碍层现象,障碍层导致的局地海温正反馈进一步增强了局地对流,从而加剧海洋失热过程,促成了巴拉望岛西北海域净热通量局地异常的出现.进一步的经验正交模态(EOF)分析表明,在季节变化尺度上,南海净热通量的第一模态(89.1%)呈同位相变化,反映了南海受冬、夏季风的交替驱动特征;其中南海北部(海南岛至台湾海峡南段的带状海域)为振幅最大区,这与该海域存在年平均最大风速有关;第二模态(10.0%)以吕宋岛至雷州半岛一线为界,南北两侧反相,并具有显著的局域特征;不仅反映了黑潮入侵与南海环流的季节变化,而且还发现巴拉望岛西北海域存在一局地极值域,对应夏季净热通量异常区. 展开更多
关键词 物理海洋学 热通量 季风 巴拉望岛 EOF
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南海南部造山运动及其与古南海俯冲的成因联系 被引量:6
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作者 赵帅 李学杰 +6 位作者 姚永坚 解习农 肖苏芸 何西 邓雨恬 石梦临 周末 《海洋地质与第四纪地质》 CAS CSCD 北大核心 2019年第5期147-162,共16页
古南海的展布范围以及俯冲消亡过程等一直是地质学家们争论的焦点问题。这不仅与南海扩张诱因密切相关,而且对南海地球动力学研究有重大的指导意义。在研究前人文献的基础上,对南海南部造山运动以及古南海俯冲过程之间的关系进行详细的... 古南海的展布范围以及俯冲消亡过程等一直是地质学家们争论的焦点问题。这不仅与南海扩张诱因密切相关,而且对南海地球动力学研究有重大的指导意义。在研究前人文献的基础上,对南海南部造山运动以及古南海俯冲过程之间的关系进行详细的论述。结果表明,南海南部构造活动主要分为两期:第一期运动从早白垩纪到晚白垩纪,古太平洋的洋壳俯冲到婆罗洲岛下方,俯冲带位于现今卢帕尔线一带,引起了曾母-南沙地块不断向西南婆罗洲靠近,并于晚白垩纪引发了碰撞造山运动。由于婆罗洲自身是由众多地块拼合而成,所以在始新世期间发生了多期碰撞之后的地块变形重组事件。最终在晚始新世(37Ma)完成最后一期变形(沙捞越运动)。第二阶段是晚始新世(35Ma)到中中新世(15.5Ma),位于西巴拉姆线以东至菲律宾卡加延一带的古南海从西巴拉姆线以东,向婆罗洲岛下方俯冲,随后扩散到沙巴以及巴拉望岛以南的地区,直至菲律宾的民都洛岛一带停止俯冲。由此产生的拖曳力是南海扩张的主要诱因。与古太平洋板块俯冲产生的效果相似,古南海的俯冲使得婆罗洲岛与南沙地块不断靠近。在中中新世(15.5Ma),引起南沙地块与婆罗洲岛在沙巴地区的碰撞(沙巴造山)以及巴拉望北部陆壳与菲律宾岛弧的碰撞而停止。由此带来的不整合面在南海南部普遍可见,甚至到达了巴拉望岛一带。而现今南沙海槽与巴拉望海槽并非是俯冲带的前渊,前者是对沙巴新近纪增生楔重力驱动变形的响应,后者是巴拉望岛北侧伸展背景下产生的半地堑盆地,在后期增生楔的作用下发生强烈沉降所形成。真正的俯冲带则分别位于南沙海槽东南部以及巴拉望海槽东南部。据现有证据推测,最少在10Ma之前古南海就在菲律宾民都洛一带停止俯冲,从而完成了整个古南海的封闭。 展开更多
关键词 古南海俯冲 造山运动 南沙地块 婆罗洲 巴拉望 南海南部
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Hepatitis C virus transmission and its risk factors within families of patients infected with hepatitis C virus in southern Iran:Khuzestan 被引量:2
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作者 Eskandar Hajiani Rahim Masjedizadeh +2 位作者 Jalal Hashemi Mehrdad Azmi Tahereh Rajabi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第43期7025-7028,共4页
AIM: To determine whether hepatitis C virus (HCV) infection of index cases increases intrafamilial transmission (sexual and nonsexual contacts) of HCV. METHODS: In a case-control descriptive study we enrolled 300-hous... AIM: To determine whether hepatitis C virus (HCV) infection of index cases increases intrafamilial transmission (sexual and nonsexual contacts) of HCV. METHODS: In a case-control descriptive study we enrolled 300-household contacts of 60 index cases (40 males and 20 females) of HCV infection and 360 pair- matched controls in Ahwaz JundiShapour University Hospitals from August 1, 1998 to September 1, 2003. The control group consisted of first time blood donors referred to the Regional Blood Transfusion Organization. Serum samples and demographic data and a medical history including the existence of risk factors for HCV (after a questionnaire on the risk factors for parenteral exposure) were obtained from each subject. Antibodies to HCV were detected employing a commercially available second-generation enzyme immunoassay (EIA, Abbott Ⅱ). Positive serum specimens were retested using a second-generation recombinant immunoblot assay (RIBA-2) and a polymerase chain reaction for HCV RNA. Data analysis was carried out for intra-household clustering. RESULTS: Only 4 of 300 (1.33%) cases of household contacts without percutaneous risk factors were positive for HCV Ab while the remaining 296 family contacts were negative for anti-HCV. The mean age of the index cases was 28.4 (Std 15.22) years. The anti-HCV prevalences in parents, spouses, children of the index cases were 0.87% (1/115), 3.39% (2/59)) and 0.79% (1/126), respectively. Among couple partners negative for anti-HCV antibodies, the mean duration of the sexual relationship was 6 years.The two-couple partners positive for anti-HCV antibodies married the index cases for longer than 15 years. The prevalence of positive HCV Ab among household contacts (1.33%) was not significantly higher than that in the controls (1%) (P > 0.06). CONCLUSION: Intrafamilial transmission of HCV is not the significant transmission route and sexual transmission does not seem to play a role in the intrafamilial spread of HCV infection. Intrafamilial transmission of HCV is possible but occurs at a low rate. 展开更多
关键词 Intrafamilial transmission Hepatitis C virus Khuzestan south-west of Iran
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西北巴拉望盆地生物礁识别与预测应用研究 被引量:3
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作者 张科 赵汝敏 +2 位作者 程岳宏 柏冠军 陈中权 《特种油气藏》 CAS CSCD 北大核心 2013年第4期22-25,152,共4页
西北巴拉望盆地油气资源主要集中在第三系生物礁储层中,该区生物礁形态多样,类型复杂,预测难度大。针对该区礁灰岩的储层特点,综合利用地震、地质、测井和钻井等资料,以地震沉积学为指导,综合运用地震属性和波阻抗反演划分有利储集相带... 西北巴拉望盆地油气资源主要集中在第三系生物礁储层中,该区生物礁形态多样,类型复杂,预测难度大。针对该区礁灰岩的储层特点,综合利用地震、地质、测井和钻井等资料,以地震沉积学为指导,综合运用地震属性和波阻抗反演划分有利储集相带,交叉应用AVO技术和烃类检测等技术研究含油气性。初步探索出1套适合于该区生物礁识别和预测的方法,摸清了礁灰岩的分布规律和储层特征,预测了生物礁的平面分布范围,划分了有利勘探相带,为该区的深入研究打下了基础。 展开更多
关键词 生物礁 地球物理方法 储层预测 西北巴拉望盆地
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Petrography and Geochemical Characterization of Dolerites from Figuil (Northern Cameroon) and Léré(Southwestern Chad) 被引量:2
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作者 Moussa Ngarena Klamadji Merlin Gountié Dedzo +1 位作者 Rigobert Tchameni Daouda Dawaï 《International Journal of Geosciences》 2020年第7期459-482,共24页
This work presents the petrographic and geochemical data of the dolerite <span>dykes crosscutting the Pan-African basement of Figuil (North-Cameroon) and </span>Léré (South-West Chad) in order to... This work presents the petrographic and geochemical data of the dolerite <span>dykes crosscutting the Pan-African basement of Figuil (North-Cameroon) and </span>Léré (South-West Chad) in order to approach their petrogenesis and their emplacement context. Two groups of dolerites have been highlighted by petrograph<span>ic and geochemical studies. These groups were discrimin</span>ated by their TiO<sub>2</sub>, Fe<sub>2</sub>O<sub>3</sub>, REE, Ba, Nb, Zr, La and Hf contents which are relatively higher in group I;group II, on the other hand, has higher MgO, Mg#, Sc, Ni and Cr contents. The mineralogical assemblage of these dolerites is made up by plagioclases, pyroxenes, olivine, oxides, amphibole, biotite and sometimes pyrite, calcite, apatite, epidote and chlorite. The behaviour of the major and trace elements suggest that studied dolerites have an evolution dominated by fractional crystallization. Most dolerite samples show higher REE concentrations and (La/Yb)<sub>N</sub> > 8.7, (Tb/Yb)<sub>N</sub> > 1.9 and Dy/Yb > 2 ratios characterizing a garnet-bearing mantle. The difference in incompatible elements between the two groups is explained by the degree of partial melting of the same source which becomes more important over time. Low (Ce/Yb)<sub>N</sub> values (3.3 - 11.58) <span>also suggest relatively low partial melting degree of the source. Fractional crystalli</span>zation process was possibly combined with minor crustal contamination as shown by enrichment of Th/Yb from group II to Group I that might be due to turbulent magma emplacement. The chemical compositions of these dolerites are similar to that of continental tholeiites with slightly moderate nega<span>tive Nb-Ta anomalies which are attributed to crustal contamination of magma</span>s. As other dolerites of Cameroon, continental tholeiitic signature of the studied dolerites is evidenced in geotectonic discrimination diagrams with Group II dolerite compositions falling within the field of tholeiitic basalts and group I within the field of alkali basalts. 展开更多
关键词 Doleritic Dykes Pan-African Basement Continental Tholeiites North-Cameroon south-west of Chad
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西北巴拉望盆地生物礁地震剖面特征与油气检测技术
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作者 朱从军 宋金甫 +2 位作者 谢英刚 郭清正 张率 《海洋石油》 CAS 2014年第3期61-65,共5页
南海西北巴拉望盆地在古新世控凹断层上盘古地形高处发育大量的生物礁和巨厚的泥岩,形成工区重要的储盖组合类型。通过多年的勘探开发,已发现27个生物礁油气田。从南海西北巴拉望盆地的演化以及生物礁的形成入手,对盆地内已发现的生物... 南海西北巴拉望盆地在古新世控凹断层上盘古地形高处发育大量的生物礁和巨厚的泥岩,形成工区重要的储盖组合类型。通过多年的勘探开发,已发现27个生物礁油气田。从南海西北巴拉望盆地的演化以及生物礁的形成入手,对盆地内已发现的生物礁油气藏的地震响应特征进行归纳总结,为有效识别生物礁油气藏打下基础。同时,利用生物礁含油气后具有高波阻抗、低频率等特征,探索出运用稀疏脉冲反演以及地震属性设置门槛值过滤的方法,检测生物礁的含油气性,以提高生物礁油气藏的勘探成功率。 展开更多
关键词 西北巴拉望盆地 生物礁 地震响应 波阻抗 门槛值 含油气性
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Migration Effects to the Marine Ecosystem of Barangay Concepcion
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作者 Marjorie Astorias-Espanola 《Journal of Life Sciences》 2017年第7期341-345,共5页
Concepcion is one of the small island barangay in the municipality of Agutaya. It has a total landmass of 132.297 hectares. It is located within Quinluban group of islands. This place has the variety of natural resour... Concepcion is one of the small island barangay in the municipality of Agutaya. It has a total landmass of 132.297 hectares. It is located within Quinluban group of islands. This place has the variety of natural resources like seaweeds, turtles, fish and other seafood. The prominent product in this island is "agar-agar" also known as Tambalang (local name) and other marine resources. This study determined the effects of migration to the marine ecosystem of the place. Survey method and interview schedule were used during the data gathering. Results show that most migrants came to plant seaweeds or agar-agar. Poverty motivated them to migrate in the area. The abundance of marine resources also is one of the factors for migration for these people. They experienced poverty and economic crisis in their previous place which motivated them to explore and migrate to support their basic needs. 展开更多
关键词 ENVIRONMENT human migration descriptive survey method Cuyo palawan Philippines
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再论南沙群岛的归属——对菲律宾新近南沙群岛地图展的批驳
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作者 王胜 《元史及民族与边疆研究集刊》 CSSCI 2017年第2期318-328,共11页
2016年8月以来菲律宾大法官卡皮奥再次举办古地图展览,意图对中国南沙群岛提出主权声索.卡皮奥认为:(1) 1600年以前西方国家所制东南亚地图中呈现的系列岛屿——“Pulo XX”即为“Spratlys”(斯普拉特利,即南沙群岛)的前身;(2) 1630年... 2016年8月以来菲律宾大法官卡皮奥再次举办古地图展览,意图对中国南沙群岛提出主权声索.卡皮奥认为:(1) 1600年以前西方国家所制东南亚地图中呈现的系列岛屿——“Pulo XX”即为“Spratlys”(斯普拉特利,即南沙群岛)的前身;(2) 1630年以后地图中出现的Isle de Paragoa/Los Bajos de Paragua等巴拉望岛以西海域中诸多未命名暗礁亦是“Spratlys”的一部分;(3)这些地图表明“Spratlys”早已属于菲律宾巴拉望岛.本文通过对相关图籍资料的考证认为,以“Pulo XX”之名出现的系列岛屿乃是越南大陆、婆罗洲近岸岛屿,与南沙群岛无关;Isle de Paragoa/Los Bajos de Paragua亦属于巴拉望岛自然大陆架的一部分,而与南沙群岛无关.相反,地图展中的相关地图及相关文本资料恰恰表明南沙群岛并不为菲律宾所有. 展开更多
关键词 菲律宾地图展 南沙群岛 Pulo Isle DE Paragoa/Los Bajos DE Paragua 巴拉望岛 卡皮奥
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An investigation into the feasibility of a hybrid generator-photovoltaic-wind farm with variable load profile:case of headland south-west of Morocco 被引量:1
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作者 Abdelkader Beyoud Ahmed Bouhaouss 《Clean Energy》 EI 2022年第3期484-495,共12页
A hybrid system proposed by three different specifications for the equipment of a tourist lodge in the headland of south-west Morocco was sized by analysing the limits of load profile constraints,such as hour-to-hour ... A hybrid system proposed by three different specifications for the equipment of a tourist lodge in the headland of south-west Morocco was sized by analysing the limits of load profile constraints,such as hour-to-hour variability(HHR),day-to-day variability(DDR)and the operating reserve rate(ROR).Based on the three-factor Doehlert matrix recommendations,the simulations employed an energy-sizing tool for hybrid renewable-energy systems.Testing was conducted with DDR at 5-30%,HHR at 10-30%and ROR at 0-20%.Under these conditions,a second-order polynomial relationship with a correlation rate of~90%was found between the net present cost(NPC)of the system,the levelized cost of electricity and the various constraint factors.The first specification,SPC(1),composed of generators and batteries,was introduced to control and validate the simulation independently of renewable energy,which showed a positive manifestation with the imposed constraints.The analysis expanded by introducing solar and wind energy resources.The SPC(2)configuration added PV modules to the SPC(1)and the SPC(3)configuration added wind turbines to SPC(2).The effect of DDR,HHR and ROR in the trials was significant by linear regression.At the same time,only DDR had a significant quadratic regression.The others,with their pairwise interactions,were insignificant.The desirability procedure made it possible to calculate the maximum limits of load profile constraint variables leading to targets of LCOE=0.41 US$/kWh and NPC=US$320080.1 of the load profile constraints:the DDR=15.47%and the HHR=26.55%at an ROR rate of 17.77%. 展开更多
关键词 hybrid system wind and photovoltaic energies HOMER software variability in load profile rate of non-load coverage model headland south-west Morocco
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Distribution of soils and solifluction layers in landslide area of South-West Germany
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作者 Birgit TERHORST 《Chinese Science Bulletin》 SCIE EI CAS 1999年第S1期173-180,共8页
As part of the MABIS research project (Mass movements in South and West-Germany)which was supported by the German Research Foundation (DFG) detailed causal, age and riskanalyses were carried out on several landslides.... As part of the MABIS research project (Mass movements in South and West-Germany)which was supported by the German Research Foundation (DFG) detailed causal, age and riskanalyses were carried out on several landslides. Investigations were carried out on the SwabianJurassic escarpment (South-West Germany). The mass movements were examined by means ofgeomorphological and pedological field mapping, through the differentiation of the solifluctionlayers and through mineralogical analyses. These investigations aimed at distinguishing betweenHolocene and Pleistocene landslides, classifying different climatic cycles of slope evolution andgathering information about potential risk areas. It could be confirmed that large rotationallandslides (earth-slump flows according to Vames 1978) occurred during the Pleistocene period,whereas during the Holocene period these fossil mass movements were only reworked anddisplaced. 展开更多
关键词 LANDSLIDE soil south-west GERMANY heavey mineral slope evolution
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南海北部陆坡晚白垩世构造逆冲及其成因 被引量:7
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作者 王长势 朱伟林 +1 位作者 钟锴 许长海 《地球科学(中国地质大学学报)》 EI CAS CSCD 北大核心 2015年第9期1505-1516,共12页
地震资料显示南海北部中生界发育褶皱和逆冲断层等挤压构造,但目前对其成因仍存在争议.通过对南海北部珠江口盆地东南部陆坡的二维地震剖面进行研究,发现在云荔低隆起-兴荔凸起-兴宁凹陷一带存在2条近NW-SE走向并往NE方向逆冲的逆断层,... 地震资料显示南海北部中生界发育褶皱和逆冲断层等挤压构造,但目前对其成因仍存在争议.通过对南海北部珠江口盆地东南部陆坡的二维地震剖面进行研究,发现在云荔低隆起-兴荔凸起-兴宁凹陷一带存在2条近NW-SE走向并往NE方向逆冲的逆断层,在东沙隆起南部有2条近南-北走向并具有压扭性质的走滑断层,上述4条断层的平面延伸距离分别约为130、110、55和58km.综合分析可知,现今位于南海南部的礼乐-巴拉望地块经中侏罗世-早白垩世与华南陆缘发生软碰撞后,在晚白垩世与华南陆缘在现今荔湾-兴宁凹陷一带进行最后的"焊接缝合",而上述4条断层可作为该次"焊接缝合"的间接证据.由于太平洋向华南的俯冲板片在晚白垩世发生了后撤,华南大陆边缘在晚白垩世末开始张裂之前可能整体为区域均衡抬升、局部陆-陆碰撞缝合的构造格局. 展开更多
关键词 南海北部陆缘 礼乐-巴拉望地块 晚白垩世 逆冲断层 走滑断层 碰撞缝合 均衡抬升 海洋地质
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