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Analysis of the Digital Skill Gap of Agricultural Extension Personnel in South-East, Nigeria
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作者 Ogbonnaya Okoro Aja Chigozie Cyril Asiabaka +1 位作者 Anthony Okorie Ani Edna Chioma Matthews-Njoku 《Agricultural Sciences》 2024年第9期1057-1070,共14页
The study analysed the digital skill gap of agricultural extension personnel on the use of digital technologies for extension services delivery in South-East, Nigeria. The specific objectives were to describe the soci... The study analysed the digital skill gap of agricultural extension personnel on the use of digital technologies for extension services delivery in South-East, Nigeria. The specific objectives were to describe the socioeconomic characteristics of agricultural extension personnel in South-East Nigeria and identify the digital skill gaps among agricultural extension personnel in the area of study. Purposive sampling technique was used to select 364 Agricultural Extension personnel for the study. Data were collected through the use of structured questionnaire and were analysed using simple descriptive statistical tools such as percentages, mean score, and standard deviation. Findings indicated that most of the personnel were male (57.8%), within the age bracket of 38 - 47 years (62.9%), had B.Sc./HND as their highest educational qualification (74.7%), married (86.3%), and had a household size of 6 - 10 Persons (57.7%). It was further revealed that the majority (70.1%) were members of professional organization, earned a monthly income of N50,001.00 - N100,000.00 (65.7%), had a work experience of 11 - 15 years (51.1%), and owned a smartphone/ iPad/laptop (91.5%). Findings further indicated that they had moderate skill gap in Basic Computer skills (Mean = 4.32), and digital communication and collaboration skills (Mean = 4.26). Findings also showed that they had a high skill gap in digital technical skills (Mean = 2.46), digital data analysis skills (Mean = 2.09), digital content creation skills (Mean = 2.43), digital ethical skills (Mean = 2.79), multimedia production skills (Mean = 2.81), and video library management skills (Mean = 2.39). The study concluded that though there exists a high digital skill gap among agricultural extension personnel in South-East, Nigeria, their socioeconomic characteristics are capable of supporting the implementation of digital extension services in the area. The study recommended that the management of Agricultural Development Programs in South-East, Nigeria, should provide digital training for extension personnel to close the digital skill gap that currently exists among the personnel. 展开更多
关键词 Agricultural Extension Personnel Socioeconomic Characteristics Digital Skill Gap south-east NIGERIA
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Epidemiology of hepatitis E in South-East Europe in the "One Health" concept 被引量:3
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作者 Anna Mrzljak Petra Dinjar-Kujundzic +5 位作者 Lorena Jemersic Jelena Prpic Ljubo Barbic Vladimir Savic Vladimir Stevanovic Tatjana Vilibic-Cavlek 《World Journal of Gastroenterology》 SCIE CAS 2019年第25期3168-3182,共15页
The significance of hepatitis E virus(HEV)as an important public health problem is rising.Until a decade ago,cases of HEV infection in Eur-ope were mainly confined to returning travelers,but nowadays,hepatitis E repre... The significance of hepatitis E virus(HEV)as an important public health problem is rising.Until a decade ago,cases of HEV infection in Eur-ope were mainly confined to returning travelers,but nowadays,hepatitis E represents an emerging zoonotic infection in many European countries.The aim of this manuscript is to perform a systematic review of the published literature on hepatitis E distribution in humans,animals and environmental samples("One Health"concept)in the South-Eastern European countries.Comparison of the available data showed that the anti-HEV seroprevalence in the South-Eastern Europe varies greatly,depending on the population studied,geographical area and methods used.The IgG seroprevalence rates in different population groups were found to be 1.1%-24.5%in Croatia,up to 20.9%in Bulgaria,5.9-%17.1%in Romania,15%in Serbia,up to 9.7%in Greece and 2%-9.7%in Albania.Among possible risk factors,older age was the most significant predictor for HEV seropositivity in most studies.Higher seroprevalence rates were found in animals.HEV IgG antibodies in domestic pigs were detected in 20%-54.5%,29.2%-50%,38.94%-50%and 31.1%-91.7%in Serbia,Bulgaria,Romania and Croatia,respectively.In wild boars seroprevalence rates were up to 10.3%,30.3%and 31.1%in Romania,Slovenia and Croatia,respectively.A high HEV RNA prevalence in wild boars in some countries(Croatia and Romania)indicated that wild boars may have a key role in the HEV epidemiology.There are very few data on HEV prevalence in environmental samples.HEV RNA was detected in 3.3%and 16.7%surface waters in Slovenia and Serbia,respectively.There is no evidence of HEV RNA in sewage systems in this region.The available data on genetic characterization show that human,animal and environmental HEV strains mainly belong to the genotype 3. 展开更多
关键词 Hepatitis E virus "One-Health" Humans Animals Environment south-east EUROPE
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Current Food and Nutrition Situation in South Asian and South-East Asian Countries 被引量:1
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作者 C. GOPALAN (Nutrition Foundation of India, C-13, Qutab Institutional Area,New Delhi-110 016, India) 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1996年第2期102-116,共15页
Food production in the countries of South and South-East Asia has shown a general upward trend during the last decade. Despite the considerable increase in population in many of these countries, food production per ca... Food production in the countries of South and South-East Asia has shown a general upward trend during the last decade. Despite the considerable increase in population in many of these countries, food production per capita in 1988-90 was significantly higher as compared to 1979-81 figures, the increase being specially marked in such countries as Vietnam, Cambodia, Indonesia, and Malaysia. Available daily calorie supply was adequate to meet the requirement. The overall pattern of food production however has shown little change, with cereal production continuing to account for a predominant part of food production. There is no evidence of a significant uptrend with respect to production of pulses, milk, horticultural products, poultry or meat production in most countries.A uniquc and unfortunate feature of the nutrition situation in South-Asian countries is that the incidence of low birth weight deliveries is as high as 34% (1990), ranging from 25% in Sri Lanka to 50% in Bangladesh (as against less than 7% in the countries of Europe and North America). Even in countries of Africa where the overall food and nutrition situation is worse than in South Asia, the incidence is well below 20%. This is a reflection of the poor state of maternal nutrition in pregnancy.Florid nutritional deficiency diseases have shown a steep decline over the last two decades, but goitre and iron deficiency anaemia continue to be major public health problems, though some headway has been made with regard to the control of the former. Severe forms of growth retardation in children have declined but the majority suffer from mild and moderate forms of growth retardation.Countries of the Region are in varying stages of developmental transition. Among the burgeoning middle classes in some of these countries there are evidences of escalation of degenerative diseases such as diabetes and coronary heart disease. With increasing life expectancy, geriatric nutritlonal problems will demand increasing attention 展开更多
关键词 FAO Current Food and Nutrition Situation in South Asian and south-east Asian Countries UNDP
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SEM Morphological Study of the Paratype of the Spinicaudatan <i>Feiyunella zhedongensis</i>(Chen and Shen, 1977) from Cretaceous of Linhai, Zhejiang, South-East China 被引量:1
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作者 Xiao Teng Gang Li 《Open Journal of Geology》 2019年第10期613-615,共3页
Spinicaudatans, a suborder of the abandoned taxonomic group “Conchostraca”, are very useful for biostratigraphic subdivision and correlation of the non-marine successions, remarkably in otherwise fossil-scarce red b... Spinicaudatans, a suborder of the abandoned taxonomic group “Conchostraca”, are very useful for biostratigraphic subdivision and correlation of the non-marine successions, remarkably in otherwise fossil-scarce red beds. Feiyunella, a monospecies spinicaudatan genus, was established based on specimens from sediments of Upper Cretaceous red beds in different localities of Zhejiang Province. The morphological examination under a scanning electron microscope of the type specimens of Feiyunella zhedongensis (Chen and Shen, 1977) has found that the paratype from the Fangyan Formation at Xiaoling of Linhai City, Zhejiang Province, is not Feiyunella, but a younger individual of Linhaiella. 展开更多
关键词 Spinicaudatan Feiyunella Linhaiella Taxonomy CRETACEOUS south-east China
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Archaeological Mineralogy and the Dawn of Gemmology:Prehistoric(7th-5th Millennium BC)Gem Minerals and Gold from the Balkans(South-East Europe) 被引量:1
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作者 Ruslan I.Kostov 《宝石和宝石学杂志》 CAS 2019年第4期25-35,共11页
The territory of the Balkan Peninsula in SE Europe is reviewed, from the point of gemmology, as the cradle of gem and decorative minerals and metals in European prehistory. During the local Neolithic period (end of 7 ... The territory of the Balkan Peninsula in SE Europe is reviewed, from the point of gemmology, as the cradle of gem and decorative minerals and metals in European prehistory. During the local Neolithic period (end of 7 th -6 th millennium BC), as material for tools or for beads, nephrite (with the earliest known Balkan nephrite culture), jadeite-omphacite and quartz (different varieties) were introduced to make pendants and idols. Large quantities of copper and gold artifacts are known since the Chalcolithic period (5 th millennium BC)(unique for the region;the largest in number of gold artifacts is the Varna I Chalcolithic necropolis in Bulgaria). The gemmological materials in the Balkans are known for malachite, antigorite serpentinite, turquoise, rock crystal, carnelian, jasper, jet and obsidian. In the Varna I necropolis (mid 5 th millennium BC) are recorded the first known complex faceted carnelian beads with 32 facets, as well as some of the most important gemmological techniques and procedures such as faceting, tumbling, annealing, miniaturization and standardization. As pigments for pottery, cinnabar, graphite and gold were used in different prehistoric sites. The earliest salt production in the Balkans is known from sites in Romania and Bulgaria, and because of its trade, salt is positively linked to a population rich with prestigious goods. The introduced possible Chalcolithic weight unit “van”(2 carats) is supposed to be the earliest known in prehistoric times. 展开更多
关键词 geoarchaeology gemmology European prehistory NEPHRITE GOLD Balkan Bulgaria south-east EUROPE
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Universal Health Coverage and Healthy Living in South-East Nigeria: How Far with Mental Health?
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作者 N. Okwudili K. Obayi Festus Asogwa Nwachukwu Ugwunna 《Open Journal of Psychiatry》 2017年第3期199-212,共14页
Background: Universal health coverage implies access to key promoting, preventive, curative, and rehabilitative health interventions for all at an affordable cost, thereby achieving equity in access and service. The m... Background: Universal health coverage implies access to key promoting, preventive, curative, and rehabilitative health interventions for all at an affordable cost, thereby achieving equity in access and service. The mentally-ill belongs to a vulnerable group that has not been given adequate attention especially in the south-eastern part of Nigeria. In September 2015, a health summit was organized in Enugu, South-East Nigeria with the sole aim of strategizing towards achieving universal health coverage in the zone. From all indications, much of the efforts being made towards achieving universal health coverage in the zone are geared towards physical conditions with mental disorders being grossly neglected. Purpose: This position paper briefly highlights the burden of mental disorders in South-East Nigeria;brings to fore the numerous challenges/barriers to effective mental health service delivery in the area;and calls for a positive change before a meaningful health coverage can be achieved in the zone (and by extension in the country). Findings: The burden of mental disorders in south-east Nigeria is heavy. Enormous barriers to mental health services in the area range from ignorance and stigmatization to self-marginalization by the unwillingness of many concerned leaders or hospital chief executives in the area to appreciate mental health and employ or increase the number of mental health professionals. Recommendations: All the stakeholders, from policy makers to consumers should wake up, recognize mental health as an indispensable part of health and take urgent and necessary measures that would ensure the promotion of mental health, prevention and treatment of mental disorders, and appropriate rehabilitation of those with mental illnesses in the zone. 展开更多
关键词 UNIVERSAL HEALTH COVERAGE Healthy Living south-east NIGERIA Mental HEALTH
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Retro-Viral Disease Status of Patients on DOTS Tuberculosis Treatment Strategy in a South-East Nigeria Teaching Hospital
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作者 Chinedu A. Idoko Chinyere Okeke +3 位作者 Chinelo I. Idoko Obiora Onowu Ikechukwu Orakwue Chuka Obienu 《Health》 2021年第8期839-845,共7页
Introduction: Tuberculosis is associated with HIV/AIDS and it has been recognized as one of the most frequent opportunistic infections in persons with HIV. Tuberculosis is the leading cause of death in people with HIV... Introduction: Tuberculosis is associated with HIV/AIDS and it has been recognized as one of the most frequent opportunistic infections in persons with HIV. Tuberculosis is the leading cause of death in people with HIV having an adverse effect on HIV progression. Objectives: The objective is to determine the retroviral disease status of patients on the DOTS strategy. Materials and Methods: A retrospective study of patients was seen at the University of Nigeria Teaching Hospital from January 2013 to April 2015. Relevant information was collected from patients’ folders. Statistical analysis was done with the SPSS and results were represented in tables. Results: 171 patients (77%) were HIV negative while 51 (23%) were positive giving an HIV negative/HIV positive ratio of 3.35:1. 97 patients (43.7%) had 6 months duration of treatment. The least was 2 patients (0.9%) that complied with their medication for 7 months. The 61 - 70 years age group accounted for the least number of HIV-positive patients. Conclusion/Recommendations: There is strong tuberculosis/HIV co-infectivity among the studied population. Strategies to reduce the burden of TB/HIV co-infection should be strengthened. 展开更多
关键词 Retroviral Status Patients DOTS TUBERCULOSIS south-east Nigeria
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Factors Confronting the Present-Day Construction Practices in South-East, Nigeria: The Professionals’ View
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作者 Fidelis Okechukwu Ezeokoli Chiagozie Bertrand Nonso Bert-Okonkwor +3 位作者 MIchael Ikechukwu Okongwu Daniel Oluwatayomi Fadumo Christian Ifeanyi Ohaedeghasi Ngozi Marykate Okoye 《Journal of Building Construction and Planning Research》 2021年第2期160-169,共10页
The study evaluates the factors confronting the present-day construction practices in South-East Nigeria. Being a survey research, questionnaires containing information relating to factors/challenges affecting constru... The study evaluates the factors confronting the present-day construction practices in South-East Nigeria. Being a survey research, questionnaires containing information relating to factors/challenges affecting construction practices were randomly administered to selected construction practitioners in South-Eastern States of Nigeria. Accordingly, a total of 240 questionnaires were administered to the selected respondents while 160 copies were completed, returned and found useful. Thus, giving a response rate of 66.67%. Data collected were analysed and presented using percentages, mean scores, principal and factor analysis, z-test and tables. The study found that the core factors that constrain present-day construction in the study area are issues related to inadequate/dearth of technical and managerial expertise, corruption and poor project planning and control;which significantly affect operational effectiveness of the construction industry in the study area. Therefore, the study concluded by recommending that thorough capacity building through training or retraining programme which should centre on areas of the issues identified should be religiously pursued in the study area. 展开更多
关键词 CONSTRUCTION Present-Day Construction Practices Construction Industry Construction Professional south-east Nigeria
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Performance of Risk Measures in Portfolio Construction on Central and South-East European Emerging Markets
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作者 Jelena Vidovic 《American Journal of Operations Research》 2011年第4期236-242,共7页
Aim of this paper is to characterize different risk measures in portfolio construction on seven Central and South-East European stock markets;Slovenia, Croatia, Hungary, Poland, Chez Republic, Bulgaria and Romania. Se... Aim of this paper is to characterize different risk measures in portfolio construction on seven Central and South-East European stock markets;Slovenia, Croatia, Hungary, Poland, Chez Republic, Bulgaria and Romania. Selected countries are members of EU, except Croatia and Turkey which have candidate status. Empirical part of this paper consists of three stages;at first descriptive statistic on stock returns was performed, afterwards different risk measures were employed in portfolio construction and in the last part, portfolios were tested in the out-of-sample period. Results indicate presence of extreme kurtosis and skewness in stock return series. Resulting portfolios incorporate stocks with extremely high kurtosis and stocks with negative skewness. Portfolio construction based only on risk and return results in major exposure to extreme returns and unsatisfactory portfolio out of sample results. 展开更多
关键词 Alternative Risk Measures CENTRAL and south-east European Emerging Markets Portfolio SKEWNESS Kurtosis
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Ore-placer shows of platinum group elements in the areal of North-Asian Superplume derivations(South-East Russia)
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作者 Vadim G.Khomich Natalya G.Boriskina 《Global Geology》 2011年第4期209-220,共12页
The sources of large and unique platinum-metal placers were the zonal alkali-ultrabasic massifs be- coming active in the Cretaceous time that gravitated to the periphery of the areal of the North-Asian Superplume (NA... The sources of large and unique platinum-metal placers were the zonal alkali-ultrabasic massifs be- coming active in the Cretaceous time that gravitated to the periphery of the areal of the North-Asian Superplume (NAS) influence. Origin of the conditions favorable for the formation of the placer platinum presence in the re- gion is governed by the plume ore-generating magmatism of several generations ( in Proterozoie and Phanerozo- ic). Ultramafite-mafite magmatism was responsible for the origin of the stratified zonal massifs subjected in the Late Paleozoic and Mesozoic to the action of granitogene derivations of the NAS. The latter provided the devel- opment of the ore-forming magmagene-fluid-metasomatic processes and favorable conditions for the platinum group elements concentration. 展开更多
关键词 platinum-bearing ore-placer south-east Russia
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Petrology, Age and Geodynamic Implication of the Panafrican Granitoids Associated with the Glito-Kpatala Shear Zone (South-East Togo)
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作者 Gnanwasou Alayi Sarakawa Abalo Malibida Kpanzou +3 位作者 Yao Agbossoumondé Essodina Padaro René-Pierre Menot Mahaman Sani Tairou 《International Journal of Geosciences》 2023年第12期1193-1225,共33页
The granitic plutons associated with the Glito-Kpatala shear zone are composed of biotite and amphibole granodiorites, biotite granites, two-mica granites and aplitic granites, which are very poorly represented. The c... The granitic plutons associated with the Glito-Kpatala shear zone are composed of biotite and amphibole granodiorites, biotite granites, two-mica granites and aplitic granites, which are very poorly represented. The chemical and mineralogical compositions of these facies indicate that they are I type and belong to high-K calc-alkaline series, with a chemical metaluminous character displayed by the granodiorites relative to the biotite and two-mica facies whose chemical compositions vary between metaluminous and peraluminous caracter. The Th/Ta (14.04 - 43.82 ppm, mean = 26.05), Th/U (2.58 to 15.05 ppm, mean = 5.85 ppm), Zr/Hf (25.27 to 37.21, mean = 30.67 ppm) and Rb/Sr (0.16 to 4.32;mean = 1.67 ppm) ratios of these granitoids reveal a strong crustal involvement in their magmatogenesis. Variations in CaO/Na<sub>2</sub>O (0.47 - 1.44 ppm), Rb/Sr (0.14 - 0.27 ppm), Rb/Ba (0.07 - 0.14 ppm) and Sr/Y (38.21 - 174.42 ppm) ratios indicate that biotite and amphibole granodiorites with their excessive Ni (135.37 - 139.51 ppm) and Cr (395.73 - 447.74 ppm) were derived from a mafic to intermediate lower continental crust where garnet and/or amphibole were stable residual assemblage minerals. The moderate Sr/Y ratios (1.81 - 9.47 ppm) and low transition elements Ni (1 - 6.44 ppm) and Cr (7.89 - 13.47 ppm) contents in both the two-mica and biotite granites are consistent with their emplacement at relatively shallow depths in the upper to mean continental crust, at pressures below 10 Kbar. In the two-mica granites, moderate CaO/Na<sub>2</sub>O (0.20 - 0.57 ppm, mean = 0.38 ppm) and Rb/Ba (0.39 - 1.37, mean = 0.84 ppm) ratios and quite varied Rb/Sr (1.53 - 4.23 ppm, mean = 2.85 ppm) ratios indicate a predominant derivation from psammitic and pelitic metasediments rather than metagreywackes. These low ratios (0.25 ≤ CaO/Na<sub>2</sub>O ≤ 0.32, mean = 0.28 ppm;0.31 ≤ Rb/Ba ≤ 0.44, mean = 0.39 ppm;1.11 ≤ Rb/Sr ≤ 1.78, mean = 0.39 ppm) in biotite granites are more consistent with melting from a metagreywacke-derived source. Evidence for the contribution of mantle-derived mafic magma with granitic magma in the plutons studied is materialized by the presence of magmatic enclaves in both granodiorites and two-mica granites, the volcanic arc geochemical signatures displayed by the plutons in geotectonic diagrams and Nb/Ta ratios (14.14 - 34.61 ppm) closer to mantle estimates. Geochemical data and radiometric dating elements suggest that the granitoids studied can be integrated into the pan-African late magmatic episode, which corresponds between 606 and 583 Ma, to the activity of transcurrent ductile strike-slips and to the synchronous emplacement of high K calc-alkaline plutons in a post-collisional context. 展开更多
关键词 Pan-African Granitoids Post-Collisional Shear Zone south-east Togo
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MESOZOIC-CENOZOIC COLLISION STRUCTURES IN THE SOUTH-EAST OF THE ASIA
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作者 Chikov B.M 《Geotectonica et Metallogenia》 1996年第Z1期111-112,共2页
Complicated system(collage)of block structures and orogenic belts had been formed in the S-E of Asia by collision prosesses in Mesozoic and Cenozoic periods. This collage began to form in early Mesozoic as a result of... Complicated system(collage)of block structures and orogenic belts had been formed in the S-E of Asia by collision prosesses in Mesozoic and Cenozoic periods. This collage began to form in early Mesozoic as a result of destruction of the continental Proterozoic-Paleozoic crust and movements of large terreines.Indosinian and Yangtze blocks(small plates)are the most characteristic block-terranes of the region; Myanmar and Songpan block systems are less representative. Variouse types of collision belts are situated between these blocks and on the periphery of the plates. They consist of concordant folded systems and shear zones. Some of these systems and shear 展开更多
关键词 MESOZOIC-CENOZOIC COLLISION STRUCTURES IN THE south-east OF THE ASIA
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Molecular genome tracking of East,Central and South African genotype of Chikungunya virus in South-east Asia between 2006 and 2009
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作者 Kamol Suwannakarn Apiradee Theamboonlers Yong Poovorawan 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2011年第7期535-540,共6页
Objective:To understand the epidemiology of the East,Central and South African(ECSA) genotype of Chikungunya virus(CHIKV) in terms of emerging and re-emerging infections,this study has been aimed at investigating the ... Objective:To understand the epidemiology of the East,Central and South African(ECSA) genotype of Chikungunya virus(CHIKV) in terms of emerging and re-emerging infections,this study has been aimed at investigating the evolutionary parameters,genomic signatures and molecular tracking of the CHIKV ECSA genotype in South-east Asia and coastal areas of the Indian Ocean between 2006 and 2009 by using phylogenetie analysis and the Bayesian Markov Chain Monte Carlo(BMCMC) evolutionary estimation.Methods:Nearly complete genome sequences of 53 CHIKV isolates from all genotypes were subjected to phylogenetie analysis and evolutionary parameter estimation.The amino acids of 67 of ECSA genotype during 2006 to 2009 were compared for finding molecular signature tracking.The ECSA genotype signatures were visualized to find the possible transmission root was projected onto a geographic map.Results: Phylogenetie analysis showed the ECSA genotype was divided into 2 groups.The first group comprises viruses from India and Southeast Asian countries.The second group consists of strains typically circulating in Sri Lanka in 2008.The evolutionary parameters of these groups depicted the time of the most recent common ancestor at approximately 7.5 years ago.The genomic signatures revealed the positions of amino acid variation in each group.Conclusions:The molecular evolution projected onto a geographical map showed the routes of CHIKV transmission from 2006 to 2009.Molecular tracking will assist in understanding transmission routes, epidemiology and molecular evolution of CHIKV. 展开更多
关键词 CHIKUNGUNYA virus EAST CENTRAL and South AFRICAN GENOTYPE GENOMIC signature Evolutionary parameter
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南海东部次海盆下地壳倾斜反射体结构特征及成因 被引量:1
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作者 徐子英 姚永坚 +4 位作者 汪俊 唐江浪 高红方 李学杰 曾程辉 《地质学报》 北大核心 2025年第1期265-276,共12页
南海东部次海盆洋壳内发育了大量强振幅的壳内倾斜反射体,它记录了海盆洋壳增生过程,深入研究海盆下地壳倾斜反射体的结构及成因,对认识南海海盆扩张过程具有重要意义。本文基于深反射多道地震剖面,刻画了东部次海盆下地壳倾斜反射体的... 南海东部次海盆洋壳内发育了大量强振幅的壳内倾斜反射体,它记录了海盆洋壳增生过程,深入研究海盆下地壳倾斜反射体的结构及成因,对认识南海海盆扩张过程具有重要意义。本文基于深反射多道地震剖面,刻画了东部次海盆下地壳倾斜反射体的结构特征及内部变形,初步探讨了其发育成因。研究表明,东部次海盆南、北部都发育强振幅的下地壳倾斜反射体,倾斜反射体大部分终止于Moho反射界面,但南北部倾斜反射体的分布范围、结构特征及成因存在明显差异。东部次海盆下地壳倾斜反射体倾斜长度北长南短,北长约15~22 km,南长约5~8 km;分布范围北大南小,北部南北向长约150 km,南部南北向长约70 km。下地壳倾斜反射区的Moho面埋深起伏差异明显北小南大,北为0.5 s,南有1.2 s。基底北部平坦南部起伏大,洋壳厚度北部厚南部薄,推测东部次海盆洋壳增生过程是非对称性和非均一的。东部次海盆下地壳倾斜反射体的成因可能与同岩浆断裂、水热循环、壳幔过渡区岩浆间隙侵入和基底深大断裂密切相关。 展开更多
关键词 南海 东部次海盆 下地壳倾斜反射体 结构特征 发育成因 洋壳增生过程
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我国冰雪运动“南展西扩东进”战略推进研究 被引量:4
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作者 於鹏 王健 +1 位作者 陈刚 倪志伟 《体育文化导刊》 北大核心 2025年第1期24-31,共8页
运用文献资料、专家访谈、实地考察等方法,探究后冬奥时期我国冰雪运动“南展西扩东进”战略推进的内在逻辑、困境,并提出路径。内在逻辑:以国家体育发展需要为根本遵循,以加快推动体育强国建设为价值目标,以“点—面—全”循序渐进为... 运用文献资料、专家访谈、实地考察等方法,探究后冬奥时期我国冰雪运动“南展西扩东进”战略推进的内在逻辑、困境,并提出路径。内在逻辑:以国家体育发展需要为根本遵循,以加快推动体育强国建设为价值目标,以“点—面—全”循序渐进为战略布局。困境:冰雪文化底蕴薄弱,常态化参与者数量不足;冰雪运动资源短缺,服务供给质量不高;冰雪产业不健全,现代化水平较低;冰雪整体竞技实力薄弱,后备人才培养体系待完善。路径:加强冰雪文化传播,营造冰雪文化氛围;统筹推进资源建设,提供高质量冰雪服务;打造冰雪全产业链,推动冰雪产业升级;提升冰雪整体竞技实力,完善后备人才培养体系。 展开更多
关键词 体育管理 冰雪运动 “南展西扩东进”战略
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“一带一路”倡议在东南亚实施以来的成效评估及风险防控
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作者 程晓勇 《贵州省党校学报》 2025年第4期35-51,共17页
“一带一路”倡议推动中国与东南亚国家的合作不断深化,在政策沟通、设施联通、贸易畅通、资金融通和民心相通方面均取得了显著的成果。但是,共建“一带一路”在东南亚国家高质量推动的同时也面临着日益复杂的政治与安全环境。一方面,... “一带一路”倡议推动中国与东南亚国家的合作不断深化,在政策沟通、设施联通、贸易畅通、资金融通和民心相通方面均取得了显著的成果。但是,共建“一带一路”在东南亚国家高质量推动的同时也面临着日益复杂的政治与安全环境。一方面,随着大国地缘竞争的加剧,“一带一路”遭遇具有强烈针对性的“竞争”、“排挤”和“干预”。另一方面,中国与东南亚国家的经济、政治与安全关系发展不平衡,双方存在的安全信任赤字不利于“一带一路”的深入推进。同时,东南亚国家存在的政局动荡、民族冲突、分离运动、恐怖主义、街头政治运动等问题也威胁着东南亚国家的政策稳定与社会安全,并影响“一带一路”合作项目的实施。对此,我国需加强海外安全保障能力建设,与共建国家共同塑造有利于“一带一路”实施的安全环境。 展开更多
关键词 “一带一路”倡议 东南亚 安全风险
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Ocean Current Dynamics and Renewable Energy from the Agulhas Current
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作者 Eckart Schumann Michael Roberts Mark Bodley 《Journal of Environmental & Earth Sciences》 2025年第4期232-245,共14页
The Agulhas Current is a major western boundary current flowing polewards on the southeast coast of South Africa.This analysis assesses its characteristics and suitability to generate power as a source of clean renewa... The Agulhas Current is a major western boundary current flowing polewards on the southeast coast of South Africa.This analysis assesses its characteristics and suitability to generate power as a source of clean renewable energy.On a section of coastline some 400 km long,over a period spanning more than 5 years an extensive set of current measurements was obtained.These data confirmed that south-westward currents with a speed greater than 1.2 m s^(-1)occurred over more than 60%of the recorded time;such ocean current speeds compare very favourably to winds required for energy generation.These currents occurred at the continental shelf break in water depths around 100 m,in the upper 50 m of the water column.Occasional current slowdowns and reversals did occur,with the major influence coming from‘Natal Pulses’,which are large-scale meanders in the Current that temporarily reversed the currents at the measurement sites.However,because of the surface temperature structure of the relevant water masses,such meanders can be identified in satellite imagery giving a few days advance warning of such current reversals.The characteristics of western boundary currents have been known for many years,but at Present,there is no operational system where this source of power is being utilised.It has tremendous potential for renewable energy generation,but is symptomatic of the many engineering challenges that still have to be solved to make such generation economically viable. 展开更多
关键词 5-Year Measurement Program Agulhas Current Consistent Currents>1.2 m s^(-1) south-east Coast of South Africa Water Depth 100 m
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全球技术竞争态势下的东盟人工智能治理 被引量:4
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作者 孙成昊 蔡依航 《东南亚研究》 2025年第2期1-23,154,共24页
随着人工智能技术的迅猛发展及广泛应用,全球技术竞争愈发激烈,参与技术治理的主体数量也快速增加。各国和地区组织都在积极制定相应的人工智能发展和治理战略。东盟作为亚太地区的关键组织与国家联合体,基于地区认同、发展和安全三方... 随着人工智能技术的迅猛发展及广泛应用,全球技术竞争愈发激烈,参与技术治理的主体数量也快速增加。各国和地区组织都在积极制定相应的人工智能发展和治理战略。东盟作为亚太地区的关键组织与国家联合体,基于地区认同、发展和安全三方面的需求,开始着手制定以东盟为中心的人工智能治理方案,以规范东南亚地区整体在这方面的可持续发展。为此,东盟遵循地区总体框架搭建、地区国家法规建设、国际人工智能合作三线并行的发展路径,致力于实现从形成松散治理共识到构建总体治理指南的转变,从发展一般数字法规到完善人工智能相关法规的跨越,以及从推进域内国家协同合作到开展国际人工智能合作的拓展。然而,东盟的人工智能治理进程面临诸多挑战,包括治理环境的不确定性、治理主体的发展不平衡性以及治理内容的宽松性。依托“东盟方式”这一基本互动原则,在全球层面推进更可信赖的人工智能治理解决方案,仍是一项长期性工作。 展开更多
关键词 东盟 人工智能治理 技术竞争 东南亚 地区发展 地区安全
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“三海联动”:美国海上制华策略及影响 被引量:3
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作者 贺先青 《亚太安全与海洋研究》 北大核心 2025年第2期91-106,I0003,共17页
南海、东海和台海(“三海”)问题事关中国国家主权与安全。美国出于海洋霸权护持的战略需求,不断强化“中国威胁”认知,提升针对中国“反介入/区域拒止”能力的反制水平,意图利用中国周边海洋矛盾,推动“三海”问题的“安全化”进程,通... 南海、东海和台海(“三海”)问题事关中国国家主权与安全。美国出于海洋霸权护持的战略需求,不断强化“中国威胁”认知,提升针对中国“反介入/区域拒止”能力的反制水平,意图利用中国周边海洋矛盾,推动“三海”问题的“安全化”进程,通过“三海联动”策略实现高效制华。操作实施上,美国通过构建“三海”叙事逻辑,打造遏制中国的军事基地网络,采取多样化军事威慑行动,构建众多双边、小多边盟伴网络,强化海上制华态势。美国此举加剧了中美海上博弈的烈度,冲击了地区海洋安全秩序构建,对中国周边海洋安全环境造成负面影响并增加了中国的海上维权成本。 展开更多
关键词 三海联动 海洋安全 美国 中国周边 南海 东海 台海
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东海古地理位置变化与迁移——古地磁学约束
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作者 徐铭辰 杨风丽 +4 位作者 张更 唐贤君 户盼盼 董若雯 庄圆 《海洋地质与第四纪地质》 北大核心 2025年第4期130-140,共11页
东海盆地作为西太平洋汇聚大陆边缘盆地体系的重要组成部分,其起源与运动过程存在诸多争议,目前就存在着是“华南地块的一部分”还是“外来微陆块”两种不同认识。为明确东海盆地早白垩世以来的古位置变化,本文首次对东海盆地内9口钻井... 东海盆地作为西太平洋汇聚大陆边缘盆地体系的重要组成部分,其起源与运动过程存在诸多争议,目前就存在着是“华南地块的一部分”还是“外来微陆块”两种不同认识。为明确东海盆地早白垩世以来的古位置变化,本文首次对东海盆地内9口钻井的白垩系—始新统岩芯进行了系统采样和古地磁实验测试研究,分析结果表明,东海盆地在早白垩世—中始新世时期一直处于15°N至30°N之间的低纬度位置,且其方位与现代方位基本一致,与华南地块之间表现出密切的古地理位置关系和构造亲缘性。对东海与华南的古位置对比分析表明,自早白垩世早期(约134 Ma)至中始新世(约40 Ma)期间,东海始终位于华南的东南位置,二者经历了纬度差持续缩小、位置逐渐靠近的三阶段过程:①从早白垩世早期至早古新世早期(约134~65 Ma),东海与华南之间的纬度差从9.0°缓慢降至6.2°;②从早古新世早期到中古新世末(约65~60 Ma),二者之间的纬度差从6.2°快速降至1.2°;③从中古新世末到中始新世(约60~40 Ma),二者之间的纬度差为1.2°~2.0°,东海与华南之间基本形成了现今空间格局,开始一体化同步运动。本研究确认了东海与华南地块之间早白垩世以来的构造亲缘性,对于东海盆地的构造演化过程研究和油气资源潜力评价具有重要意义。 展开更多
关键词 古地磁学 古地理位置 早白垩世—中始新世 华南地块 东海盆地
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