897 resultados para Middle East and North Africa
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(l) The Pacific basin (Pacific area) may be regarded as moving eastwards like a double zip fastener relative to the continents and their respective plates (Pangaea area): opening in the East and closing in the West. This movement is tracked by a continuous mountain belt, the collision ages of which increase westwards. (2) The relative movements between the Pacific area and the Pangaea area in the W-E/E-W direction are generated by tidal forces (principle of hypocycloid gearing), whereby the lower mantle and the Pacific basin or area (Pacific crust = roof of the lower mantle?) rotate somewhat faster eastwards around the Earth's spin axis relative to the upper mantle/crust system with the continents and their respective plates (Pangaea area) (differential rotation). (3) These relative West to East/East to West displacements produce a perpetually existing sequence of distinct styles of opening and closing ocean basins, exemplified by the present East to West arrangement of ocean basins around the globe (Oceanic or Wilson Cycle: Rift/Red Sea style; Atlantic style; Mediterranean/Caribbean style as eastwards propagating tongue of the Pacific basin; Pacific style; Collision/Himalayas style). This sequence of ocean styles, of which the Pacific ocean is a part, moves eastwards with the lower mantle relative to the continents and the upper-mantle/crust of the Pangaea area. (4) Similarly, the collisional mountain belt extending westwards from the equator to the West of the Pacific and representing a chronological sequence of collision zones (sequential collisions) in the wake of the passing of the Pacific basin double zip fastener, may also be described as recording the history of oceans and their continental margins in the form of successive Wilson Cycles. (5) Every 200 to 250 m.y. the Pacific basin double zip fastener, the sequence of ocean styles of the Wilson Cycle and the eastwards growing collisional mountain belt in their wake complete one lap around the Earth. Two East drift lappings of 400 to 500 m.y. produce a two-lap collisional mountain belt spiral around a supercontinent in one hemisphere (North or South Pangaea). The Earth's history is subdivided into alternating North Pangaea growth/South Pangaea breakup eras and South Pangaea growth/North Pangaea breakup eras. Older North and South Pangaeas and their collisional mountain belt spirals may be reconstructed by rotating back the continents and orogenic fragments of a broken spiral (e.g. South Pangaea, Gondwana) to their previous Pangaea growth era orientations. In the resulting collisional mountain belt spiral, pieced together from orogenic segments and fragments, the collision ages have to increase successively towards the West. (6) With its current western margin orientated in a West-East direction North America must have collided during the Late Cretaceous Laramide orogeny with the northern margin of South America (Caribbean Andes) at the equator to the West of the Late Mesozoic Pacific. During post-Laramide times it must have rotated clockwise into its present orientation. The eastern margin of North America has never been attached to the western margin of North Africa but only to the western margin of Europe. (7) Due to migration eastwards of the sequence of ocean styles of the Wilson Cycle, relative to a distinct plate tectonic setting of an ocean, a continent or continental margin, a future or later evolutionary style at the Earth's surface is always depicted in a setting simultaneously developed further to the West and a past or earlier style in a setting simultaneously occurring further to the East. In consequence, ahigh probability exists that up to the Early Tertiary, Greenland (the ArabiaofSouth America?) occupied a plate tectonic setting which is comparable to the current setting of Arabia (the Greenland of Africa?). The Late Cretaceous/Early Tertiary Eureka collision zone (Eureka orogeny) at the northern margin of the Greenland Plate and on some of the Canadian Arctic Islands is comparable with the Middle to Late Tertiary Taurus-Bitlis-Zagros collision zone at the northern margin of the Arabian Plate.
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The ancestors of present-day man (Homo sapiens sapiens) appeared in East Africa some three and a half million years ago (Australopithecs), and then migrated to Europe, Asia, and later to the Americas, thus beginning the differentiation process. The passage from nomadic to sedentary life took place in the Middle East in around 8000 BC. Wars, spontaneous migrations and forced migrations (slave trade) led to enormous mixtures of populations in Europe and Africa and favoured the spread of numerous parasitic diseases with specific strains according to geographic area. The three human plasmodia (Plasmodium falciparum, P. vivax, and P. malariae) were imported from Africa into the Mediterranean region with the first human migrations, but it was the Neolithic revolution (sedentarisation, irrigation, population increase) which brought about actual foci for malaria. The reservoir for Leishmania infantum and L. donovani - the dog - has been domesticated for thousands of years. Wild rodents as reservoirs of L. major have also long been in contact with man and probably were imported from tropical Africa across the Sahara. L. tropica, by contrast, followed the migrations of man, its only reservoir. L. infantum and L. donovani spread with man and his dogs from West Africa. Likewise, for thousands of years, the dog has played an important role in the spread and the endemic character of hydatidosis through sheep (in Europe and North Africa) and dromadary (in the Sahara and North Africa). Schistosoma haematobium and S. mansoni have existed since prehistoric times in populations living in or passing through the Sahara. These populations then transported them to countries of Northern Africa where the specific, intermediary hosts were already present. Madagascar was inhabited by populations of Indonesian origin who imported lymphatic filariosis across the Indian Ocean (possibly of African origin since the Indonesian sailors had spent time on the African coast before reaching Madagascar). Migrants coming from Africa and Arabia brought with them the two African forms of bilharziosis: S. haematobium and S. mansoni.
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Thirty microsatellite markers were analysed in 1426 goats from 45 traditional or rare breeds in 15 European and Middle Eastern countries. In all populations inbreeding was indicated by heterozygosity deficiency (mean FIS = 0.10). Genetic differentiation between breeds was moderate with a mean FST value of 0.07, but for most (c. 71%) northern and central European breeds, individuals could be assigned to their breeds with a success rate of more than 80%. Bayesian-based clustering analysis of allele frequencies and multivariate analysis revealed at least four discrete clusters: eastern Mediterranean (Middle East), central Mediterranean, western Mediterranean and central/northern Europe. About 41% of the genetic variability among the breeds could be explained by their geographical origin. A decrease in genetic diversity from the south-east to the north-west was accompanied by an increase in the level of differentiation at the breed level. These observations support the hypothesis that domestic livestock migrated from the Middle East towards western and northern Europe and indicate that breed formation was more systematic in north-central Europe than in the Middle East. We propose that breed differentiation and molecular diversity are independent criteria for conservation.
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The location of the La Galite Archipelago on the Internal/External Zones of the Maghrebian Chain holds strong interest for the reconstruction of the geodynamic evolution of the Mesomediterranean Microplate-Africa Plate Boundary Zone. New stratigraphic and petrographic data on sedimentary successions intruded upon by plutonic rocks enabled a better definition of the palaeogeographic and palaeotectonic evolutionary model of the area during the early-middle Miocene. The lower Miocene sedimentary units (La Galite Flysch and Numidian-like Flysch) belong to the Mauritanian (internal) and Massylian (external) sub-Domains of the Maghrebian Chain, respectively. These deposits are related to a typical syn-orogenic deposition in the Maghrebian Flysch Basin Domain, successively backthrusted above the internal units. The backthrusting age is post-Burdigalian (probably Langhian-Serravallian) and the compressional phase represents the last stage in the building of the accretionary wedge of the Maghrebian orogen. These flysch units may be co-relatable to the similar well-known formations along the Maghrebian and Betic Chains. The emplacement of potassic peraluminous magmatism, caused local metamorphism in the Late Serravallian-Early Tortonian (14–10 Ma), after the last compressional phase (backthrusting), during an extensional tectonic event. This extensional phase is probably due to the opening of a slab break-off in the deep subduction system. La Galite Archipelago represents a portion of the Maghrebian Flysch Basin tectonically emplaced above the southern margin of the “Mesomediterranean Microplate” which separated the Piemontese-Ligurian Ocean from a southern oceanic branch of the Tethys (i.e. the Maghrebian Flysch Basin). The possible presence of an imbricate thrust system between La Galite Archipelago and northern Tunisia may be useful to exclude the petroleum exploration from the deformed sectors of the offshore area considered.
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Item 231-B-1
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Mode of access: Internet.
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Mode of access: Internet.
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Mode of access: Internet.
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This report shows the phlebotomine vectorial role in the endemic cutaneous leishmaniasis situated in the middle and north-eastern region of the São Paulo, Brazil. Analysis of information encloses a sandfly man-biting fauna of four different patches of residual forest. So, using the human-bait and Shannon trap for a period of one year we have caught 16,869 sandflies. The predominance of Lutzomyia intermedia (85,6%) was clear. Moreover, the low density of Lutzomyia whitmani and Lutzomyia pessoai and their epidemiological implications at present and in the past are discussed. Information about the daily activity of some species is given and we emphasize for the first time, the diurnal activity of Lutzomyia firmatoi in the São Paulo State.
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Dissertação para obtenção do Grau de Mestre em Engenharia Geológica (Georrecursos)
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v.7:no.10(1910)
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BACKGROUND: Due to its history, with a high number of migration events, the Mediterranean basin represents a challenging area for population genetic studies. A large number of genetic studies have been carried out in the Mediterranean area using different markers but no consensus has been reached on the genetic landscape of the Mediterranean populations. In order to further investigate the genetics of the human Mediterranean populations, we typed 894 individuals from 11 Mediterranean populations with 25 single-nucleotide polymorphisms (SNPs) located on the X-chromosome. RESULTS: A high overall homogeneity was found among the Mediterranean populations except for the population from Morocco, which seemed to differ genetically from the rest of the populations in the Mediterranean area. A very low genetic distance was found between populations in the Middle East and most of the western part of the Mediterranean Sea.A higher migration rate in females versus males was observed by comparing data from X-chromosome, mt-DNA and Y-chromosome SNPs both in the Mediterranean and a wider geographic area.Multilocus association was observed among the 25 SNPs on the X-chromosome in the populations from Ibiza and Cosenza. CONCLUSION: Our results support both the hypothesis of (1) a reduced impact of the Neolithic Wave and more recent migration movements in NW-Africa, and (2) the importance of the Strait of Gibraltar as a geographic barrier. In contrast, the high genetic homogeneity observed in the Mediterranean area could be interpreted as the result of the Neolithic wave caused by a large demic diffusion and/or more recent migration events. A differentiated contribution of males and females to the genetic landscape of the Mediterranean area was observed with a higher migration rate in females than in males. A certain level of background linkage disequilibrium in populations in Ibiza and Cosenza could be attributed to their demographic background.
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AIMS: This study aimed to estimate the prevalence of life-time abstainers, former drinkers and current drinkers, adult per-capita consumption of alcohol and pattern of drinking scores, by country and Global Burden of Disease region for 2005, and to forecast these indicators for 2010. DESIGN: Statistical modelling based on survey data and routine statistics. SETTING AND PARTICIPANTS: A total of 241 countries and territories. MEASUREMENTS: Per-capita consumption data were obtained with the help of the World Health Organization's Global Information System on Alcohol and Health. Drinking status data were obtained from Gender, Alcohol and Culture: An International Study, the STEPwise approach to Surveillance study, the World Health Survey/Multi-Country Study and other surveys. Consumption and drinking status data were triangulated to estimate alcohol consumption across multiple categories. FINDINGS: In 2005 adult per-capita annual consumption of alcohol was 6.1 litres, with 1.7 litres stemming from unrecorded consumption; 17.1 litres of alcohol were consumed per drinker, 45.8% of all adults were life-time abstainers, 13.6% were former drinkers and 40.6% were current drinkers. Life-time abstention was most prevalent in North Africa/Middle East and South Asia. Eastern Europe and Southern sub-Saharan Africa had the most detrimental pattern of drinking scores, while drinkers in Europe (Eastern and Central) and sub-Saharan Africa (Southern and West) consumed the most alcohol. CONCLUSIONS: Just over 40% of the world's adult population consumes alcohol and the average consumption per drinker is 17.1 litres per year. However, the prevalence of abstention, level of alcohol consumption and patterns of drinking vary widely across regions of the world.