993 resultados para Africa, North--Maps


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Mode of access: Internet.

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Mode of access: Internet.

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Includes index.

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The houbara bustard, Chlamydotis undulata, is a declining cryptic desert bird whose range extends from North Africa to Central Asia. Three subspecies are currently recognized by geographical distribution and morphology: C.u.fuertaventurae, C.u.undulata and C.u.macqueenii. We have sequenced 854 bp of mitochondrial control region from 73 birds to describe their population genetic structure with a particular sampling focus on the connectivity between C.u.fuertaventurae and C.u.undulata along the Atlantic seaboard of North Africa. Nucleotide and haplotypic diversity varied among the subspecies being highest in C.u.undulata, lowest in C.u.fuertaventurae and intermediate in C.u.macqueenii. C.u.fuertaventurae and C.u.undulata are paraphyletic and an average nucleotide divergence of 2.08% splits the later from C.u.macqueenii. We estimate that C.u.fuertaventurae and C.u.undulata split from C.u.macqueenii approximately 430 000 years ago. C.u.fuertaventurae and C.u.undulata are weakly differentiated (F-ST = 0.27, N-m = 1.3), indicative of a recent shared history. Archaeological evidence indicates that houbara bustards have been present on the Canary Islands for 130-170 000 years. However, our genetic data point to a more recent separation of C.u.fuertaventurae and C.u.undulata at around 20-25 000 years. Concordant archaeological, climatic opportunities for colonization and genetic data point to a scenario of: (i) initial colonization of the Canary Islands about 130 000 years ago; (ii) a period of secondary contact 19-30 000 years ago homogenizing any pre-existing genetic structure followed by; (iii) a period of relative isolation that persists today.

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The Wet Tropics World Heritage Area in Far North Queens- land, Australia consists predominantly of tropical rainforest and wet sclerophyll forest in areas of variable relief. Previous maps of vegetation communities in the area were produced by a labor-intensive combination of field survey and air-photo interpretation. Thus,. the aim of this work was to develop a new vegetation mapping method based on imaging radar that incorporates topographical corrections, which could be repeated frequently, and which would reduce the need for detailed field assessments and associated costs. The method employed G topographic correction and mapping procedure that was developed to enable vegetation structural classes to be mapped from satellite imaging radar. Eight JERS-1 scenes covering the Wet Tropics area for 1996 were acquired from NASDA under the auspices of the Global Rainforest Mapping Project. JERS scenes were geometrically corrected for topographic distortion using an 80 m DEM and a combination of polynomial warping and radar viewing geometry modeling. An image mosaic was created to cover the Wet Tropics region, and a new technique for image smoothing was applied to the JERS texture bonds and DEM before a Maximum Likelihood classification was applied to identify major land-cover and vegetation communities. Despite these efforts, dominant vegetation community classes could only be classified to low levels of accuracy (57.5 percent) which were partly explained by the significantly larger pixel size of the DEM in comparison to the JERS image (12.5 m). In addition, the spatial and floristic detail contained in the classes of the original validation maps were much finer than the JERS classification product was able to distinguish. In comparison to field and aerial photo-based approaches for mapping the vegetation of the Wet Tropics, appropriately corrected SAR data provides a more regional scale, all-weather mapping technique for broader vegetation classes. Further work is required to establish an appropriate combination of imaging radar with elevation data and other environmental surrogates to accurately map vegetation communities across the entire Wet Tropics.

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Relief shown pictorially.

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Context:Blood pressure (BP) tracks from childhood to adulthood, and has ethnic variations. Therefore, it is important to assess the situation of pediatric BP in different populations. This study aims to systematically review the studies conducted on BP in Iranian children and adolescents. Evidence Acquisition: We conducted a systematic review on published and national data about pediatric BP in Iran, our search was conducted in Pub Med, Medline, ISI, and Scopus, as well as in national databases including Scientific Information database (SID), IranMedex and Irandoc from 1990 to 2014. Results: We found 1373 records in the primary search including 840 from international and 533 from national databases. After selection and quality assessment phases, data were extracted from 36 papers and four national data sources. Mean systolic BP (SBP) varied from 90.1 ± 14 mmHg (95% CI 89.25, 90.94) to 120.2 ± 12.3 (118.98, 121.41) mmHg, and for diastolic BP (DBP) from 50.7 ± 11.4 (50.01, 51.38) to 79.2 ± 12.3 (77.95, 80.44) mmHg. The frequency of elevated BP had large variation in sub-national studies with rates as low as 0.4% (0.009, 1.98) for high SBP and as high as 24.1% (20.8, 27.67) for high DBP. At national level, three surveys reported slightly raised rates of elevated BP from 2009 to 2012. Conclusions: The findings provide practical information on BP levels in Iranian pediatric population. Although differences exist on the findings of various studies, this review underscores the necessity of tracking BP from childhood, and implementing interventions for primordial prevention of hypertension.

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The Stockholm Programme, allied to the Lisbon Treaty, heralds a new era of development of the EU provisions on cross-border law enforcement. The focus is shifting from the ongoing internal EU developments to the external relations of the EU. Many North African countries have had long legal relationships with the EU through the Euro-Mediterranean Partnerships. A number of these partnership agreements make express references, at the political level, to the development of cross-border law enforcement provision, as is the case of Morocco and Algeria with regard to drug trafficking and manufacture, or the lengthy references by Egypt to many of the crimes of interest to the EU’s own law enforcement legal framework. Algeria is currently focusing on modernising their own police forces, with both Algeria and Tunisia, reforming their criminal judicial frameworks. Another key player, Libya, currently has no legal agreements with the EU, and at least until the recent conflict, maintained an observer status in the Euro-Mediterranean process. At a practitioner level, the European Police College (CEPOL) is currently involved in the Euromed Police II programme. Clearly momentum is developing, both within the EU and from a number of Euro-Med North African countries to develop closer law enforcement co-operation. This may well develop further with the recent changes in governments of a number of North African countries. The EU approach in the Police and Judicial Cooperation in Criminal Matters (PJCCM) policy area is to develop a legal framework upon which EU cross-border law enforcement will be based. The current EU cross-border law enforcement framework is the product of many years of multi-level negotiations. Challenges will arise as new countries from different legal and policing traditions will attempt to engage with already highly detailed legal and practice frameworks. The shared European legal traditions will not necessarily be reflected in the North African countries. This chapter critically analyses, from an EU legal perspective the problems and issues that will be encountered as the EU’s North African partner countries attempt to articulate into the existing, and still developing EU cross-border law enforcement framework.

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O presente artigo tem por base a investigação desenvolvida em âmbito de doutorameto sobre as fortalezas de Ceuta e de Mazagão, as primeiras fortificações abaluartadas construídas no Norte de África pelos portugueses na década de 1540. Apesar de corresponderem a conjuntos com diferentes configurações, adaptados ao contexto em que se inserem, as duas fortificações possuem importantes características em comum no que respeita às lógicas arquitectónicas em que se baseiam, às tipologias utilizadas, às relações que estabelecem com o território envolvente e ao modo como as pré-existências integram a construção. Construídas na sequência das experiências mais avançadas, desenvolvidas em grande parte pelos arquitetos italianos, estas fortificações integram a primeira linha do processo de evolução da arquitetura militar internacional. Entre os principais modelos que podemos reconhecer como referência na concepção das fortificações de Ceuta e de Mazagão, tendo em conta algumas das suas características mais significativas, destacam-se obras como a Fortaleza velha de Livorno, de Giuliano da Sangallo, a Fortaleza da Basso, em Florença, de António da Sangallo-o-novo e o Castelo San Telmo, em Nápoles, de Pedro Luìs Escrivà.

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Through long-range transport of dust, the North-African desert supplies essential minerals to the Amazon rain forest. Since North African dust reaches South America mostly during the Northern Hemisphere winter, the dust sources active during winter are the main contributors to the forest. Given that the Bod,l, depression area in southwestern Chad is the main winter dust source, a close link is expected between the Bod,l, emission patterns and volumes and the mineral supply flux to the Amazon. Until now, the particular link between the Bod,l, and the Amazon forest was based on sparse satellite measurements and modeling studies. In this study, we combine a detailed analysis of space-borne and ground data with reanalysis model data and surface measurements taken in the central Amazon during the Amazonian Aerosol Characterization Experiment (AMAZE-08) in order to explore the validity and the nature of the proposed link between the Bod,l, depression and the Amazon forest. This case study follows the dust events of 11-16 and 18-27 February 2008, from the emission in the Bod,l, over West Africa (most likely with contribution from other dust sources in the region) the crossing of the Atlantic Ocean, to the observed effects above the Amazon canopy about 10 days after the emission. The dust was lifted by surface winds stronger than 14 m s(-1), usually starting early in the morning. The lofted dust, mixed with biomass burning aerosols over Nigeria, was transported over the Atlantic Ocean, and arrived over the South American continent. The top of the aerosol layer reached above 3 km, and the bottom merged with the boundary layer. The arrival of the dusty air parcel over the Amazon forest increased the average concentration of aerosol crustal elements by an order of magnitude.

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Predicting the potential geographical distribution of a species is particularly important for pests with strong invasive abilities. Tetranychus evansi Baker & Pritchard, possibly native to South America, is a spider mite pest of solanaceous crops. This mite is considered an invasive species in Africa and Europe. A CLIMEX model was developed to predict its global distribution. The model results fitted the known records of T. evansi except for some records in dry locations. Dryness as well as excess moisture stresses play important roles in limiting the spread of the mite in the tropics. In North America and Eurasia its potential distribution appears to be essentially limited by cold stress. Detailed potential distribution maps are provided for T. evansi in the Mediterranean Basin and in Japan. These two regions correspond to climatic borders for the species. Mite establishment in these areas can be explained by their relatively mild winters. The Mediterranean region is also the main area where tomato is grown in open fields in Europe and where the pest represents a threat. According to the model, the whole Mediterranean region has the potential to be extensively colonized by the mite. Wide expansion of the mite to new areas in Africa is also predicted. Agricultural issues highlighted by the modelled distribution of the pest are discussed.

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A revised kinematic model for the motions of Africa and Iberia relative to Europe since the Middle Jurassic is presented in order to provide boundary conditions for Alpine-Mediterranean reconstructions. These motions were calculated using up-to-date kinematic data predominantly based on magnetic isochrons in the Atlantic Ocean and published by various authors during the last 15 years. It is shown that convergence of Africa with respect to Europe commenced during the Cretaceous Normal Superchron (CNS), between chrons MO and 34 (120-83 Ma). This motion was subjected to fluctuations in convergence rates characterised by two periods of relatively rapid convergence (during Late Cretaceous and Eocene-Oligocene times) that alternated with periods of slower convergence (during the Paleocene and since the Early Miocene). Distinct changes in plate kinematics are recognised in the motion of Iberia with respect to Europe, indicated by: (1) a Late Jurassic-Early Cretaceous left-lateral strike-slip motion; (2) Late Cretaceous convergence; (3) Paleocene quiescence; (4) a short period of right-lateral strike-slip motion; and (5) final Eocene-Oligocene convergence. Based on these results, it is speculated that a collisional episode in the Alpine orogeny at ca. 65 Ma resulted in a dramatic decrease in the relative plate motions and that a slower motion since the Early Miocene promoted extension in the Mediterranean back-arc basins. (C) 2002 Elsevier Science B.V. All rights reserved.