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浅论当代非洲华商的现状、特点和机遇 预览
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作者 甘振军 《八桂侨刊》 2019年第2期50-58,共9页
当代非洲华商以民间企业和小商人为市场主体,主要从事餐饮、批发零售、进出口贸易、地产等行业。他们利用地缘和业缘的认同和优势,形成了同乡社会网络,并在面临多重挑战的情况下取得成功。当代非洲华商在中非关系中的地位和作用体现在:... 当代非洲华商以民间企业和小商人为市场主体,主要从事餐饮、批发零售、进出口贸易、地产等行业。他们利用地缘和业缘的认同和优势,形成了同乡社会网络,并在面临多重挑战的情况下取得成功。当代非洲华商在中非关系中的地位和作用体现在:帮助非洲提升经济发展能力;大陆华商企业成为中非贸易的主体;民营企业开拓非洲市场是企业转型升级的机遇;非洲华商在帮助民营企业落地非洲起到沟通桥梁的作用,还间接承担着传播中华文化的使命;华商精神有助于促进民心相通。在“一带一路”背景下,非洲作为极具潜力的消费市场和投资场所,中非双方都在改善营商环境。非洲华商网络在新时代发生了深刻变化,非洲互联网设施的不断完善和电子商务的普及等新趋势为华商发展带来新的机遇。 展开更多
关键词 非洲 华商 中非关系
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Systematic review and meta-analysis of esophageal cancer in Africa:Epidemiology,risk factors,management and outcomes 预览
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作者 Akwi W Asombang Nathaniel Chishinga +6 位作者 Alick Nkhoma Jackson Chipaila Bright Nsokolo Martha Manda-Mapalo Joao Filipe G Montiero Lewis Banda Kulwinder S Dua 《世界胃肠病学杂志:英文版》 SCIE CAS 2019年第31期4512-4533,共22页
BACKGROUND Esophageal cancer(EC)is associated with a poor prognosis,particularly so in Africa where an alarmingly high mortality to incidence ratio prevails for this disease.AIM To provide further understanding of EC ... BACKGROUND Esophageal cancer(EC)is associated with a poor prognosis,particularly so in Africa where an alarmingly high mortality to incidence ratio prevails for this disease.AIM To provide further understanding of EC in the context of the unique cultural and genetic diversity,and socio-economic challenges faced on the African continent.METHODS We performed a systematic review of studies from Africa to obtain data on epidemiology,risk factors,management and outcomes of EC.A non-systematic review was used to obtain incidence data from the International Agency for Research on Cancer,and the Cancer in Sub-Saharan reports.We searched EMBASE,PubMed,Web of Science,and Cochrane Central from inception to March 2019 and reviewed the list of articles retrieved.Random effects metaanalyses were used to assess heterogeneity between studies and to obtain odds ratio(OR)of the associations between EC and risk factors;and incidence rate ratios for EC between sexes with their respective 95%confidence intervals(CI).RESULTS The incidence of EC is higher in males than females,except in North Africa where it is similar for both sexes.The highest age-standardized rate is from Malawi(30.3 and 19.4 cases/year/100000 population for males and females,respectively)followed by Kenya(28.7 cases/year/100000 population for both sexes).The incidence of EC rises sharply after the age of 40 years and reaches a peak at 75 years old.Meta-analysis shows a strong association with tobacco(OR 3.15,95%CI:2.83-3.50).There was significant heterogeneity between studies on alcohol consumption(OR 2.28,95%CI:1.94-2.65)and on low socioeconomic status(OR 139,95%CI:1.25-1.54)as risk factors,but these could also contribute to increasing the incidence of EC.The best treatment outcomes were with esophagectomy with survival rates of 76.6%at 3 years,and chemo-radiotherapy with an overall combined survival time of 267.50 d.CONCLUSION Africa has high incidence and mortality rates of EC,with preventable and nonmodifiable risk factors.Men in this setting are at increased r 展开更多
关键词 ESOPHAGEAL CANCER in AFRICA ESOPHAGEAL SQUAMOUS cell carcinoma CANCER in AFRICA Systematic review
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欧洲大国的海外利益保护论析——以法国、英国和德国在非洲的利益保护为例
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作者 杨娜 《世界经济与政治》 CSSCI 北大核心 2019年第5期103-130,159-160共29页
非洲国家陆续独立后,以法国、英国和德国为代表的欧洲大国仍然新旧方式并用以保证它们非洲的海外利益。在此过程中,它们形成了一些共同特性:政府是维护海外利益的关键行为体、军事力量是有力保障、跨国公司控制非洲国家的关键领域、加... 非洲国家陆续独立后,以法国、英国和德国为代表的欧洲大国仍然新旧方式并用以保证它们非洲的海外利益。在此过程中,它们形成了一些共同特性:政府是维护海外利益的关键行为体、军事力量是有力保障、跨国公司控制非洲国家的关键领域、加强在欧盟层面的协调。优先特定地区或领域、借助多边机制、援助和投资先行、平衡国内各方利益以及创建主导型机制是三国海外利益保护的基本做法。受地缘环境、历史经历、国家实力、国际分工及产业结构等因素影响三国海外利益的分布与类型,导致了海外利益保护方式和侧重点各有不同。法国通过投资、驻军、货币挂钩等途径在经济、贸易和金融领域保持对非全面影响,确保海外利益最大化。英国延续并发展了殖民时期“因地制宜”、宗主国管理与当地情况相融合的模式,为英国维护并拓展在非利益减少阻碍。德国倾向于采用和平的多边方式与非洲打交道。当前国际环境与地区形势的变化带来诸多不确定性,对法、英、德在非利益保护和拓展带来了挑战。三国为了扭转国内或地区的不利局面,均积极发展对非关系,力图维护其在非特殊利益,进而扩展其全球影响力。 展开更多
关键词 欧洲大国 海外利益 军事干预 多边行动 非洲事务
中非农产品贸易在1992—2017年变化特征分析及政策建议 预览
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作者 杨军 董婉璐 崔琦 《农林经济管理学报》 CSSCI 北大核心 2019年第3期395-406,共12页
近年来,中非农产品贸易规模在显著增长的同时,呈现出新的趋势和特征。在深入分析中非农产品贸易在1992 2017年变化的基础上,测算中非农产品贸易的国际竞争力和互补性。研究表明:中非农产品贸易整体呈现增长趋势,在双方农产品贸易中的重... 近年来,中非农产品贸易规模在显著增长的同时,呈现出新的趋势和特征。在深入分析中非农产品贸易在1992 2017年变化的基础上,测算中非农产品贸易的国际竞争力和互补性。研究表明:中非农产品贸易整体呈现增长趋势,在双方农产品贸易中的重要性显著提升。然而,中非农产品贸易面临突出的结构性问题,双边农产品贸易的互补性程度不断降低,将显著制约中非农产品贸易增长潜力。这种贸易结构特征表明:单纯依靠贸易促进的方式已难以有效促进中非农产品贸易增长,亟需在生产技术、装备和能力等方面开展更深层次的交流与合作。 展开更多
关键词 农产品贸易 中国 非洲 比较优势 互补性
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“一带一路”建设背景下的中非水产养殖产业合作分析 预览
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作者 敬小军 朱健 +3 位作者 姜海洲 张霖 叶伟 徐跑 《中国渔业经济》 2019年第2期93-102,共10页
"一带一路"建设根植于丝绸之路的历史土壤,重点面向亚欧非大陆,非洲已成为"一带一路"向西推进的重要组成部分.日益减少的捕捞渔业资源和不断增长的粮食需求使得非洲国家越来越关注水产养殖业发展.从世界范围来看,... "一带一路"建设根植于丝绸之路的历史土壤,重点面向亚欧非大陆,非洲已成为"一带一路"向西推进的重要组成部分.日益减少的捕捞渔业资源和不断增长的粮食需求使得非洲国家越来越关注水产养殖业发展.从世界范围来看,非洲水产养殖总产量依然很低,非洲大量的养殖资源(水资源、劳动力资源、市场资源等)尚未得到充分开发.本文对非洲水域资源、水产养殖产业的发展现状和主要问题进行了研究,对中非水产养殖产业合作的机遇与挑战进行了分析,提出建立技术培训中心、科技创新中心、研企合作示范、深化合作机制等方面的建议. 展开更多
关键词 一带一路 非洲 水产养殖 产业合作
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非洲几内亚红宝石的宝石学特征及成分特征 预览
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作者 冯珺妍 陈美华 《宝石和宝石学杂志》 CAS 2019年第3期26-36,共11页
以非洲几内亚近年出产的红宝石为研究对象,借助宝石学常规仪器,结合激光剥蚀等离子质谱仪、紫外-可见光吸收光度计、傅里叶变换红外光谱仪和显微拉曼光谱仪系统探究其宝石学特征、成分特征和谱学特征,并与非洲其他产地红宝石成分特征进... 以非洲几内亚近年出产的红宝石为研究对象,借助宝石学常规仪器,结合激光剥蚀等离子质谱仪、紫外-可见光吸收光度计、傅里叶变换红外光谱仪和显微拉曼光谱仪系统探究其宝石学特征、成分特征和谱学特征,并与非洲其他产地红宝石成分特征进行比较。结果表明,几内亚红宝石多数带有紫色调或者褐色调,表面有熔蚀壳,内部包裹体丰富,透明度较差。根据颜色分为紫红色和橘红色两个系列,不同颜色红宝石中Cr、Fe质量分数和Cr/Fe比例有明显差别,均低于优质红宝石。非洲几内亚红宝石中Fe的质量分数为0.05%~0.15%,可以根据Fe质量分数与非洲肯尼亚(<0.0015%)、马达加斯加(0.15%~0.28%)、莫桑比克部分矿区(>0.28%)的红宝石粗略区分,但和坦桑尼亚部分矿区的红宝石(0.030%~0.156%)有重叠。紫红色系列样品随着颜色由浅到深,紫外-可见吸收光谱谱线红移,蓝紫色调增强;橘红色系列样品呈现紫区吸收强度大,绿区吸收强度小。红外吸收光谱中,深紫色样品出现了微弱的3310,3076cm^-1和Ti-OH有关的吸收峰,与深紫色样品中Ti质量分数相对较高相关。拉曼光谱测得几内亚红宝石的包裹体有磷灰石、硬水铝石和金红石。 展开更多
关键词 红宝石 宝石学特征 化学成分 非洲几内亚
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非洲孔子学院管理面临的问题及对策研究 预览
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作者 徐永亮 徐丽华 《管理观察》 2019年第2期155-159,共5页
非洲孔子学院的飞速发展,使得其在人力资源、教学、跨文化传播、机构文化及安全危机应对管理等方面面临一系列问题。本文作者作为实践者和研究者,对非洲孔子学院管理亟待解决的几个问题进行了深入研究,并提出相应的应对策略.
关键词 非洲 孔子学院 管理 问题 对策
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非洲职业教育的新发展──非盟《促进青年就业的职业技术教育大陆战略》解析 预览
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作者 翟俊卿 钦夏昱 《职业技术教育》 北大核心 2019年第9期69-74,共6页
非盟组织于2014年6月颁布了《促进青年就业的职业技术教育大陆战略》,该战略主要包括五方面内容:以技能需求为导向,建立全面连贯的职业教育体系;重新定义'行业'和'职业',明确培训目标;制定具体的培训和课程内容,在情境... 非盟组织于2014年6月颁布了《促进青年就业的职业技术教育大陆战略》,该战略主要包括五方面内容:以技能需求为导向,建立全面连贯的职业教育体系;重新定义'行业'和'职业',明确培训目标;制定具体的培训和课程内容,在情境中实习;加强师资培训,保障教学质量;完善职业教育基础设施,提高设备利用率。与2007年非盟颁布的《非洲职业技术教育和培训振兴战略》相比,新战略体现了非盟组织和各个成员国对职业教育的支持力度大大增强;基于范式转变,培养工作机会的创造者;发挥生产部门作用,融入职业教育发展的全过程。 展开更多
关键词 非洲 职业教育 非盟 “大陆战略”
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A Genetic Map of Africa
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作者 British Council 《英语世界》 2019年第5期125-126,共2页
It is surprising that,although disease is such a big problem in Africa,95%of medical research happens in Europe.Genetic research in a continent where genetic diversity is high,like Africa,can give us a better understa... It is surprising that,although disease is such a big problem in Africa,95%of medical research happens in Europe.Genetic research in a continent where genetic diversity is high,like Africa,can give us a better understanding of why people get certain diseases.A new study helps us understand genetic variation in different regions and groups of people.It also shows how humans moved across Africa thousands of years ago. 展开更多
关键词 ACTIVITY A GENETIC MAP of AFRICA
Starting up Africa
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作者 Ge Lijun 《中国与非洲:英文版》 2019年第4期44-45,共2页
On his second trip to Africa in August last year, Jack Ma said it is the entrepreneurs who will propel the African economy. The dynamic executive chairman of Alibaba Group, the Chinese e-conimerce giant, made the comm... On his second trip to Africa in August last year, Jack Ma said it is the entrepreneurs who will propel the African economy. The dynamic executive chairman of Alibaba Group, the Chinese e-conimerce giant, made the comment while speaking at a special event in Johannesburg, South Africa. He was there to announce a new $10-million prize to support African entrepreneurs. 展开更多
关键词 AFRICA JACK MA
China's Growing Healthcare Presence in Africa
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《中国与非洲:英文版》 2019年第4期48-49,共2页
China has increased its presence in the healthcare sector on the African continent, resp on ding to issues such as the continued growth rate of malaria infections, as well as providing aid during the out break of the ... China has increased its presence in the healthcare sector on the African continent, resp on ding to issues such as the continued growth rate of malaria infections, as well as providing aid during the out break of the Ebola virus. China has sent thousands of medical workers to Africa, and has also provided funds for vai ious projects across the continent. How has this aid developed throughout the decades, and how has China helped Africa develop its own healthcare infrastructure and capacity? 展开更多
关键词 China GROWING Healthcare PRESENCE AFRICA
Keeping the Peace
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作者 Godfrey Olukya 《中国与非洲:英文版》 2019年第1期32-33,共2页
When Uganda sent its troops to Somalia to keep peace in the war-torn country in East Africa in March 2007,many locals considered the move would backfire miserably. But the Ugandan armed forces proved their critics wro... When Uganda sent its troops to Somalia to keep peace in the war-torn country in East Africa in March 2007,many locals considered the move would backfire miserably. But the Ugandan armed forces proved their critics wrong and showed their mettie,going on to successfully execute peacekeeping missions not only in Somalia,but also in other countries in the region. 展开更多
关键词 Uganda sent EAST AFRICA CRITICS WRONG
An Unforgettable Day
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《中国与非洲:英文版》 2019年第7期52-53,共2页
Every year, Africa Day is celebrated on May 25. The day marks the anniversary of the founding of the Organization of African Unity (OAU) on May 25,1963. It is a symbol of the struggle of Africa for liberation, emancip... Every year, Africa Day is celebrated on May 25. The day marks the anniversary of the founding of the Organization of African Unity (OAU) on May 25,1963. It is a symbol of the struggle of Africa for liberation, emancipation and development. On this occasion, Martin Mpana, Ambassador of Cameroon to China and Dean of the African Group in Beijing, and Rahamtalla M. Osman. 展开更多
关键词 AFRICA DAY ORGANIZATION of AFRICAN UNITY
The Key Triggers for the Transitioning of Informal SMMEs to Formal SMMEs:A Baseline Survey of the Gauteng Province——South Africa 预览
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作者 Paul Kibuuka Deon Tustin 《心理学研究:英文版》 2019年第1期32-44,共13页
This paper presents the views of 623 informal and formal small,medium,and micro enterprises(SMMEs)operating in the Gauteng Province of South Africa.The objective of the study was to identify challenges and benefits th... This paper presents the views of 623 informal and formal small,medium,and micro enterprises(SMMEs)operating in the Gauteng Province of South Africa.The objective of the study was to identify challenges and benefits that are experienced by SMMEs during and after the registration process leading to the transition from informal to formal business,the level of awareness by the SMMEs of the registration information,and the procedures in addition to the potential factors that inspire or discourage informal and prospective business registration.The reason for including both informal and formal SMMEs in the survey was to compare the perceptions of these groups of businesses regarding the triggers and/or barriers to register as a formal business.The results show that for both informal and formal businesses,the liability of paying taxes was a major challenge while improved workers’health and safety accrued as a major benefit.Own research emerged as the main source of access to business registration information and procedure.The costs involved in registration were highlighted as one of the major factors discouraging registration but the prospects of expanding the customer base and the ability to achieve a higher turnover as some of the main inspiring factors.The study recommends the development of policies that provide an enabling environment for sustainable enterprises but also to implement measures that improve productivity through access to finance,skills,infrastructure,markets,and technology transfers. 展开更多
关键词 SMME INFORMAL TRIGGERS business REGISTRATION transition FORMAL EMPLOYEES TURNOVER and South Africa
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Hydrogeochemical and multi-tracer investigations of arsenic-affected aquifers in semi-arid West Africa 预览
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作者 Anja Bretzler Lucien Stolze +5 位作者 Julien Nikiema Franck Lalanne Elaheh Ghadiri Matthias S. Brennwald Massimo Rolle Mario Schirmer 《地学前缘:英文版》 CAS CSCD 2019年第5期1685-1699,共15页
The semi-arid Sahel regions ofWest Africa rely heavily on groundwater from shallow to moderately deep (<100 m b.g.l.) crystalline bedrock aquifers for drinking water production.Groundwater quality may be affected b... The semi-arid Sahel regions ofWest Africa rely heavily on groundwater from shallow to moderately deep (<100 m b.g.l.) crystalline bedrock aquifers for drinking water production.Groundwater quality may be affected by high geogenic arsenic (As) concentrations (>10 μg/L) stemming from the oxidation of sulphide minerals (pyrite,arsenopyrite) in mineralised zones.These aquifers are still little investigated,especially concerning groundwater residence times and the influence of the annual monsoon season on groundwater chemistry.To gain insights on the temporal aspects of As contamination,we have used isotope tracers (noble gases,3H,stable water isotopes (2H,18O)) and performed hydrochemical analyses on groundwater abstracted from tube wells and dug wells in a small study area in southwestern Burkina Faso.Results revealed a great variability in groundwater properties (e.g.redox conditions,As concentrations,water level,residence time) over spatial scales of only a few hundred metres,characteristic of the highly heterogeneous fractured underground.Elevated As levels are found in oxic groundwater of circum-neutral pH and show little relation with any of the measured parameters.Arsenic concentrations are relatively stable over the course of the year,with little effect seen by the monsoon.Groundwater residence time does not seem to have an influence on As concentrations,as elevated As can be found both in groundwater with short (<50 a) and long (>10^3 a) residence times as indicated by 3He/4He ratios spanning three orders of magnitude.These results support the hypothesis that the proximity to mineralised zones is the most crucial factor controlling As concentrations in the observed redox/pH conditions.The existence of very old water portions with residence times >10^3 years already at depths of <50 m b.g.l.is a new finding for the shallow fractured bedrock aquifers of Burkina Faso,suggesting that overexploitation of these relatively low-yielding aquifers may be an issue in the future. 展开更多
关键词 Arsenic Groundwater chemistry WEST AFRICA Fractured aquifers RESIDENCE time NOBLE gases
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AFRICA THIS MONTH
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《中国投资》 2019年第8期10-13,共4页
1坦桑尼亚推广湖区旅游据坦桑尼亚《每日新闻报》3月18日报道,旅游与自然资源部副部长卡亚苏表示,坦政府决心将湖区推广成为热门旅游目的地之一,目前正在努力研究并进行大力推广,以确保湖区环线的旅游景点得到改善,并呼吁投资者抓住机... 1坦桑尼亚推广湖区旅游据坦桑尼亚《每日新闻报》3月18日报道,旅游与自然资源部副部长卡亚苏表示,坦政府决心将湖区推广成为热门旅游目的地之一,目前正在努力研究并进行大力推广,以确保湖区环线的旅游景点得到改善,并呼吁投资者抓住机遇、实现双赢。此前,议会批准了将湖区五个野生动物保护区升级为国家公园。卡亚苏副部长表示,政府正在考虑改善基础设施如扩建和修复机场等,以便利游客到达这些地区游览。 展开更多
关键词 电子网络 尼日利亚 AFRICA THIS MONTH 共同市场 蒙巴萨 全球粮食危机 国际招标 石油区块 经济特区 孕产妇死亡率 液化天然气
非洲水电开发及投资研究 预览
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作者 冯一铭 周保中 卢杰 《发电技术》 2019年第2期201-206,共6页
非洲大陆水电资源蕴藏量极为丰富,但由于缺乏资金投入和技术支持,非洲的水电资源一直没有得到大规模开发和利用。而电力短缺是阻碍非洲社会经济发展的主要"绊脚石"之一。通过大量的数据分析和统计,对非洲各区域水电开发潜力... 非洲大陆水电资源蕴藏量极为丰富,但由于缺乏资金投入和技术支持,非洲的水电资源一直没有得到大规模开发和利用。而电力短缺是阻碍非洲社会经济发展的主要"绊脚石"之一。通过大量的数据分析和统计,对非洲各区域水电开发潜力和开发现状进行了剖析,对主要国家的水电开发规划进行解读,给出了非洲水电投资空间评估;深入分析长期以来中国企业在非洲水电开发的特点,总结中国企业的优势,并为拟在非洲投资水电的中国企业提出注意事项和建议。 展开更多
关键词 非洲 水电 电力市场 企业投资
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From South Africa to North America 预览
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作者 Zheng Wen 《中外文化交流:英文版》 2019年第6期42-43,共2页
After nearly four and a half year term in South Africa, I took my departure from Johannesburg in South Africa on the way back to Beijing on the last day of 2018.
关键词 SOUTH AFRICA NORTH AMERICA JOHANNESBURG
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Infections with Helicobacter pylori and challenges encountered in Africa 预览
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作者 Stella Smith Muinah Fowora Rinaldo Pellicano 《世界胃肠病学杂志:英文版》 SCIE CAS 2019年第25期3183-3195,共13页
Helicobacter pylori(H.pylori)is the causative agent of gastritis,peptic ulcer disease,mucosa associated lymphoid tissue lymphoma and gastric cancer(GC).While this bacterium infects 50%of the world’s population,in Afr... Helicobacter pylori(H.pylori)is the causative agent of gastritis,peptic ulcer disease,mucosa associated lymphoid tissue lymphoma and gastric cancer(GC).While this bacterium infects 50%of the world’s population,in Africa its prevalence reach as high as 80%as the infection is acquired during childhood.Risk factors for H.pylori acquisition have been reported to be mainly due to overcrowding,to have infected siblings or parent and to unsafe water sources.Despite this high H.pylori prevalence there still does not exist an African guideline,equivalent to the Maastricht V/Florence Consensus Report of the European Helicobacter and Microbiota Study Group for the management of this infection.In this continent,although there is a paucity of epidemiologic data,a contrast between the high prevalence of H.pylori infection and the low incidence of GC has been reported.This phenomenon is the so-called“African Enigma”and it has been hypothesized that it could be explained by environmental,dietary and genetic factors.A heterogeneity of data both on diagnosis and on therapy have been published.In this context,it is evident that in several African countries the increasing rate of bacterial resistance,mainly to metronidazole and clarithromycin,requires continental guidelines to recommend the appropriate management of H.pylori.The aim of this manuscript is to review current literature on H.pylori infection in Africa,in terms of prevalence,risk factors,impact on human health,treatment and challenges encountered so as to proffer possible solutions to reduce H.pylori transmission in this continent. 展开更多
关键词 HELICOBACTER PYLORI AFRICA Risk factors African ENIGMA Prevalence Treatment Diagnosis
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Crystallization and impact history of a meteoritic sample of early lunar crust (NWA 3163) refined by atom probe geochronology 预览
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作者 L.F. White D.E. Moser +3 位作者 K.T. Tait B. Langelier I. Barker J.R. Darling 《地学前缘:英文版》 CAS CSCD 2019年第5期1841-1848,共8页
Granulitic lunar meteorites offer rare insights into the timing and nature of igneous,metamorphic and impact processes in the lunar crust.Accurately dating the different events recorded by these materials is very chal... Granulitic lunar meteorites offer rare insights into the timing and nature of igneous,metamorphic and impact processes in the lunar crust.Accurately dating the different events recorded by these materials is very challenging,however,due to low trace element abundances (e.g.Sm,Nd,Lu,Hf),rare micrometerscale U-Th-bearing accessory minerals,and disturbed Ar-Ar systematics following a multi-stage history of shock and thermal metamorphism.Here we report on micro-baddeleyite grains in granulitic mafic breccia NWA 3163 for the first time and show that targeted microstructural analysis (electron backscatter diffraction) and nanoscale geochronology (atom probe tomography) can overcome these barriers to lunar chronology.A twinned (-90°/<401>) baddeleyite domain yields a 232Th/208Pb age of 4328 ± 309 Ma,which overlaps with a robust secondary ion mass spectrometry (SIMS) 207Pb/206Pb age of 4308± 18.6 Ma and is interpreted here as the crystallization age for the igneous protolith of NWA 3163.A second microstructural domain,< 2 mm in width,contains patchy overprinting baddeleyite and yields a Th-Pb age of 2175± 143 Ma,interpreted as dating the last substantial impact event to affect the sample.This finding demonstrates the potential of combining microstructural characterization with nanoscale geochronology when resolving complex P-T-t histories in planetary materials,here yielding the oldest measured crystallization age for components of lunar granulite NWA 3163 and placing further constraints on the formation and evolution of lunar crust. 展开更多
关键词 BADDELEYITE U-TH-PB ISOTOPES EBSD Atom probe tomography GEOCHRONOLOGY NORTHWEST Africa 3163
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