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Sample records for north africa region

  1. Wet phases in the Sahara/Sahel region and human migration patterns in North Africa

    PubMed Central

    Castañeda, Isla S.; Mulitza, Stefan; Schefuß, Enno; Lopes dos Santos, Raquel A.; Sinninghe Damsté, Jaap S.; Schouten, Stefan

    2009-01-01

    The carbon isotopic composition of individual plant leaf waxes (a proxy for C3 vs. C4 vegetation) in a marine sediment core collected from beneath the plume of Sahara-derived dust in northwest Africa reveals three periods during the past 192,000 years when the central Sahara/Sahel contained C3 plants (likely trees), indicating substantially wetter conditions than at present. Our data suggest that variability in the strength of Atlantic meridional overturning circulation (AMOC) is a main control on vegetation distribution in central North Africa, and we note expansions of C3 vegetation during the African Humid Period (early Holocene) and within Marine Isotope Stage (MIS) 3 (≈50–45 ka) and MIS 5 (≈120–110 ka). The wet periods within MIS 3 and 5 coincide with major human migration events out of sub-Saharan Africa. Our results thus suggest that changes in AMOC influenced North African climate and, at times, contributed to amenable conditions in the central Sahara/Sahel, allowing humans to cross this otherwise inhospitable region. PMID:19910531

  2. Wet phases in the Sahara/Sahel region and human migration patterns in North Africa.

    PubMed

    Castañeda, Isla S; Mulitza, Stefan; Schefuss, Enno; Lopes dos Santos, Raquel A; Sinninghe Damsté, Jaap S; Schouten, Stefan

    2009-12-01

    The carbon isotopic composition of individual plant leaf waxes (a proxy for C(3) vs. C(4) vegetation) in a marine sediment core collected from beneath the plume of Sahara-derived dust in northwest Africa reveals three periods during the past 192,000 years when the central Sahara/Sahel contained C(3) plants (likely trees), indicating substantially wetter conditions than at present. Our data suggest that variability in the strength of Atlantic meridional overturning circulation (AMOC) is a main control on vegetation distribution in central North Africa, and we note expansions of C(3) vegetation during the African Humid Period (early Holocene) and within Marine Isotope Stage (MIS) 3 ( approximately 50-45 ka) and MIS 5 ( approximately 120-110 ka). The wet periods within MIS 3 and 5 coincide with major human migration events out of sub-Saharan Africa. Our results thus suggest that changes in AMOC influenced North African climate and, at times, contributed to amenable conditions in the central Sahara/Sahel, allowing humans to cross this otherwise inhospitable region. PMID:19910531

  3. MENA 1.1 - An Updated Geophysical Regionalization of the Middle East and North Africa

    SciTech Connect

    Walters, B.; Pasyanos, M.E.; Bhattacharyya, J.; O'Boyle, J.

    2000-03-01

    This short report provides an update to the earlier LLNL paper entitled ''Preliminary Definition of Geophysical Regions for the Middle East and North Africa'' (Sweeney and Walter, 1998). This report is designed to be used in combination with that earlier paper. The reader is referred to Sweeney and Walter (1998) for all details, including definitions, references, uses, shortcomings, etc., of the regionalization process. In this report we will discuss only those regions in which we have changed the boundaries or velocity structure from that given by the original paper. The paper by Sweeney and Walter (1998) drew on a variety of sources to estimate a preliminary, first-order regionalization of the Middle East and North Africa (MENA), providing regional boundaries and velocity models within each region. The model attempts to properly account for major structural discontinuities and significant crustal thickness and velocity variations on a gross scale. The model can be used to extrapolate sparse calibration data within a distinct geophysical region. This model can also serve as a background model in the process of forming station calibration maps using intelligent interpolation techniques such as kriging, extending the calibration into aseismic areas. Such station maps can greatly improve the ability to locate and identify seismic events, which in turn improves the ability to seismically monitor for underground nuclear testing. The original model from Sweeney and Walter (1998) was digitized to a 1{sup o} resolution, for simplicity we will hereafter refer to this model as MENA 1.0. The new model described here has also been digitized to a 1{sup o} resolution and will be referred to as MENA1.1 throughout this report.

  4. Silent Epidemic of Depression in Women in the Middle East and North Africa Region

    PubMed Central

    Eloul, Liyam; Ambusaidi, Aamal; Al-Adawi, Samir

    2009-01-01

    Background: As the world is being gripped by economic depression, international psychological epidemiologists have amassed evidence to suggest that psychological depression and its variants are becoming leading contributors to the global burden of disease with the Middle East and North Africa (MENA) region being no exception. Aim: The main aim of the present discourse, based on a review of the available literature, is to discuss critically whether women in the MENA region have a higher rate of psychological depression than those in other parts of the globe. Result: From the present synthesis, it emerges that the rate of depression may not be necessarily unique to the region. Conclusion: Although no society has totally overcome the marginalisation and lack of empowerment of women, in order to come to grips to this complex issue more vigorously designed epidemiological studies, using taxonomies that are standardised for cross-cultural populations, are needed to quantify the psychological functioning of women. PMID:21509269

  5. A Variable-resolution Surface Wave Dispersion Study of Eurasia, North Africa, and Surrounding Regions

    SciTech Connect

    Pasyanos, M E

    2005-03-21

    This paper presents the results of a large-scale study of surface wave dispersion performed across Eurasia and North Africa. Improvements were made to previous surface wave work by enlarging the study region, increasing path density, improving spatial resolution, and expanding the period range. This study expands the coverage area northwards and eastwards relative to a previous dispersion analysis, which covered only North Africa and the Middle East. We have significantly increased the number of seismograms examined and group velocity measurements made. We have now made good quality dispersion measurements for about 30,000 Rayleigh wave and 20,000 Love wave paths, and have incorporated measurements from several other researchers into the study. A conjugate gradient method was employed for the group velocity tomography, which improved the inversion from the previous study by adopting a variable smoothness. This technique allows us to go to higher resolution where the data allow without producing artifacts. The current results include both Love and Rayleigh wave inversions across the region for periods from 7 to 100 seconds at 1{sup o} resolution. Short period group velocities are sensitive to slow velocities associated with large sedimentary features such as the Caspian Sea, West Siberian Platform, Mediterranean Sea, Bay of Bengal, Tarim Basin, and Persian Gulf. Intermediate periods are sensitive to differences in crustal thickness, such as those between oceanic and continental crust or along orogenic zones and continental plateaus. At longer periods, fast velocities are consistently found beneath cratons while slow upper mantle velocities occur along rift systems, subduction zones, and collision zones such as the Tethys Belt. We have compared the group velocities at various periods with features such as sediment thickness, topographic height, crustal thickness, proximity to plate boundaries, lithospheric age and lithospheric thickness, and find significant

  6. Preliminary maps of crustal thickness and regional seismic phases for the Middle East and North Africa

    SciTech Connect

    Sweeney, J.J.

    1995-09-06

    As part of the development of regional seismic discrimination methods for the Middle East and North Africa (MENA) the author is building a database of information related to seismic propagation and crustal structure as well as associated geologic-tectonic and geophysical data. He hopes to use these data to construct and test models of regional seismic propagation and evaluate various detection/discrimination scenarios. To date, the database has been developed by building on a list of references for MENA provided by the Institute for the Study of the Continents (INSTOC) at Cornell University. To this list the author has added an equal number of references resulting from his own literature search which has emphasized papers dealing with seismicity and regional and teleseismic phase data. This paper represents an initial attempt to consolidate some of the information from the database into a form useful to researchers modeling regional seismic waveforms. The information compiled in this report is supplemental to the INSTOC database and has not been compiled anywhere else. What follows is a series of maps which illustrate the spatial variation of seismic phase velocities and crustal thickness. The text identifies the sources of information used in the map preparation. Data for the compilation of these maps has come from an initial search of the database as it presently exists and is not intended to be exhaustive. The author hopes that this initial exercise will help to identify areas and types of data that are deficient and help to focus future data gathering activities.

  7. Study of Regional Volcanic Impact on the Middle East and North Africa using high-resolution global and regional models

    NASA Astrophysics Data System (ADS)

    Osipov, Sergey; Dogar, Mohammad; Stenchikov, Georgiy

    2016-04-01

    High-latitude winter warming after strong equatorial volcanic eruptions caused by circulation changes associated with the anomalously positive phase of Arctic Oscillation is a subject of active research during recent decade. But severe winter cooling in the Middle East observed after the Mt. Pinatubo eruption of 1991, although recognized, was not thoroughly investigated. These severe regional climate perturbations in the Middle East cannot be explained by solely radiative volcanic cooling, which suggests that a contribution of forced circulation changes could be important and significant. To better understand the mechanisms of the Middle East climate response and evaluate the contributions of dynamic and radiative effects we conducted a comparative study using Geophysical Fluid Dynamics Laboratory global High Resolution Atmospheric Model (HiRAM) with the effectively "regional-model-resolution" of 25-km and the regional Weather Research and Forecasting (WRF) model focusing on the eruption of Mount Pinatubo on June 15, 1991 followed by a pronounced positive phase of the Arctic Oscillation. The WRF model has been configured over the Middle East and North Africa (MENA) region. The WRF code has been modified to interactively account for the radiative effect of volcanic aerosols. Both HiRAM and WRF capture the main features of the MENA climate response and show that in winter the dynamic effects in the Middle East prevail the direct radiative cooling from volcanic aerosols.

  8. A GCM investigation of dust aerosol impact on the regional climate of North Africa and South/East Asia

    NASA Astrophysics Data System (ADS)

    Gu, Y.; Xue, Y.; De Sales, F.; Liou, K. N.

    2016-04-01

    The climatic effects of dust aerosols in North Africa and South/East Asia have been investigated using an atmospheric general circulation model, NCEP/GCM/SSiB (Simplified Simple Biosphere Model) and the three-dimensional aerosol data simulated by the Goddard Chemistry Aerosol Radiation and Transport (GOCART) model. GCM simulations show that due to the scattering and absorption of solar radiation by dust particles, surface temperature decreases over both regions, accompanied by a reduced sensible heat flux. However, precipitation responses are different in these two regions. Due to differences in dust location and the associated heating with respect to the rainfall band and circulation, the effect of dust could either enhance or suppress precipitation. Over the North Africa region where dust particles are mainly located to the north of rainfall band, heating of the air column by dust particles forces a stronger ascent motion over dust layers, which induces an anomalous subsidence (or a weakened upward motion) and suppressed cyclonic circulation to its south where precipitation reduces. Furthermore, both humidity and cloud decrease due to the heating in the middle troposphere (semi-direct effect). In South/East Asia, dust particles are located in the upper troposphere over the major rainfall band during the monsoon season, especially Southwest India and the coastal area of Bay of Bengal. Heating of the air column increases upward motion and strengthens cyclonic circulation. Humidity also increases due to the draw-in of the low level moist air. Therefore, cloud and precipitation increase over South/East Asia associated with dust effect. During the pre-monsoon season, when dust particles are located to the north of the monsoon rainfall band, the heating effect results in shifting precipitation northward. The heating of air column due to dust particles, not surface cooling, plays the major role in precipitation changes. The anomalous upward motion over dust regions will

  9. The transatlantic dust transport from North Africa to the Americas—Its characteristics and source regions

    NASA Astrophysics Data System (ADS)

    Gläser, Gregor; Wernli, Heini; Kerkweg, Astrid; Teubler, Franziska

    2015-11-01

    Transport of Saharan dust over the Atlantic to the Americas is a relevant process since dust is a nutrient for marine and terrestrial ecosystems. It is therefore important to better quantify the frequency and amount of transatlantic dust transport, its preferred altitude and duration, and the regions of dust origin. This study uses a novel combination of Eulerian and Lagrangian diagnostics, applied to a previously validated 5 year simulation of the fifth generation European Centre for Medium Range Weather Forecast-Hamburg-model (ECHAM5)/Modular Earth Submodel System (MESSy) Atmospheric Chemistry model, to quantify these dust transport characteristics and their seasonal variations. Results confirm the previously found preferred transatlantic dust pathways: in boreal winter and spring, African dust is mainly transported below 800 hPa toward South America, whereas in summer and autumn the preferred pathway is to the Caribbean and occurs in a layer up to 500 hPa. The averaged transport duration from dust emission to deposition is 10 days in winter for deposition in the Amazon region and almost 12 days in summer for deposition in the Caribbean. These estimates were obtained by combining correlation analyses of Eulerian dust fluxes and trajectory calculations. The latter were also essential to identify the main source regions of transatlantic dust transport, which were found in all seasons in northwestern Africa (Algeria, Mali, and Mauritania) but not farther east, e.g., in the Bodélé Depression. A specific Lagrangian analysis for this dust emission hot spot suggests that wet deposition associated with the Intertropical Convergence Zone in winter and the African monsoon in summer inhibits Bodélé dust to leave the African continent.

  10. Preliminary definition of geophysical regions for the Middle East and North Africa

    SciTech Connect

    Sweeney, J J; Walter, B

    1998-12-01

    The ability to calibrate seismic stations to improve the monitoring of the Comprehensive Test Ban Treaty is partially limited by the availability of seismic events with known locations and source properties. To confidently extrapolate from these events to aseismic regions, and to properly account for discontinuities in seismic properties requires accurate geophysical models. This paper lays out a preliminary, first-order, regionalization of the Middle East and North African (MENA) region. The model specifies boundaries and velocity structures based on the geology and tectonics of the region, previously published studies, and empirical data observations by the LLNL group. This model is a starting point and is expected to be improved and refined by comparisons with ongoing tomography efforts and the collection of new data. We anticipate that this model and its successors will prove useful as a background model in the process of forming station calibration maps based on intelligent interpolation techniques such as kriging. We also hope the model, as it improves and demonstrates some predictive power, will provide a reference model for broader CTBT research efforts in detection, location and discrimination as well as other aspects of earth science.

  11. Toward a Sustainable Society in the Mena (Middle East and North Africa) Region: Roadmap and Priorities

    ERIC Educational Resources Information Center

    El-Bassiouny, Noha

    2012-01-01

    The Business and Society Research Cluster (BSRC) at the German University in Cairo, the El-Khazindar Business Research and Case Center at the American University in Cairo and Misr El-Kheir (MEK) Foundation, Egypt, hosted the region's first sustainability and corporate social responsibility (CSR) case studies conference, entitled "Toward a…

  12. Public health considerations for mass gatherings in the Middle East and North Africa (MENA) region.

    PubMed

    AlNsour, M; Fleischauer, A

    2013-01-01

    This review describes major mass gatherings in the MENA region and the public health implications of these events, and provides recommendations for public health officials of the host country. Through our search of the literature for peer-reviewed publications, we identified relevant 77 papers; all were related to the annual Hajj. Using the information obtained from the literature review, the Eastern Mediterranean Public Health Network (EMPHNET) and the Centers for Disease Control and Prevention (CDC) developed and conducted 2 workshops on Public Health Surveillance during Mass Gatherings for field epidemiology training programmes and ministry of health focal points from 10 countries. The main potential public health concerns associated with mass gatherings include: infectious diseases (e.g. respiratory disease, gastro-intestinal tract disease, foodborne disease), injuries, traffic accidents, heat-related illnesses, insect stings, non-communicable diseases and terrorism. PMID:24673098

  13. Emigration flows from North Africa to Europe.

    PubMed

    Kassar, Hassène; Marzouk, Diaa; Anwar, Wagida A; Lakhoua, Chérifa; Hemminki, Kari; Khyatti, Meriem

    2014-08-01

    The region of North Africa (NA) represents a striking locality regarding migration with several migration patterns, namely emigration in the form of labour export to Europe and North America and, to a lesser extent, to the Arab Gulf area. The latter has increased enormously in the last decade because of the political instability in most of the NA countries. The aim of the present chapter was to explore the patterns of migration stocks and flows in NA countries, based on several websites, systematic review of journals, comparable data available by the United Nations and by the International Organization of Migration. The NA region has become an area of transit migration and labour migration. Emigrant flows from NA countries towards Europe and North America are increasing this decade more than towards the Arab Gulf countries after being replaced by Asian labour. The recent increase in the proportion of women among the migrant population is remarkable. Remittances sent by African migrants have become an important source of external finance for countries of origin. Transient and irregular migration to Egypt originates at the borders with Sudan, Palestine and Libya with destination to the Euro Mediterranean countries. In Tunisia and Morocco, irregular migrants originate from Sub-Saharan Africa to the northern borders. The NA countries serve as departure rather than destination countries, and migration flows to the Euro-Mediterranean countries through legal or illegal routes. PMID:25107991

  14. Comorbidities associated with COPD in the Middle East and North Africa region: association with severity and exacerbations

    PubMed Central

    Mahboub, Bassam; Alzaabi, Ashraf; Iqbal, Mohammed Nizam; Salhi, Hocine; Lahlou, Aïcha; Tariq, Luqman; El Hasnaoui, Abdelkader

    2016-01-01

    Objective To assess the frequency of comorbidities in subjects with COPD and their association with respiratory symptom severity and COPD exacerbations. Materials and methods This was an analysis of the BREATHE study, a cross-sectional survey of COPD conducted in the general population of eleven countries in the Middle East and North Africa, including Pakistan. The study population consisted of a sample of subjects with COPD for whom the presence of comorbidities was documented. Three questionnaires were used. The screening questionnaire identified subjects who fulfilled an epidemiological case definition of COPD and documented any potential comorbidities; the detailed COPD questionnaire collected data on respiratory symptoms, COPD exacerbations, and comorbidities associated with COPD; the COPD Assessment Test collected data on the impact of respiratory symptoms on well-being and daily life. Results A total of 2,187 subjects were positively screened for COPD, of whom 1,392 completed the detailed COPD questionnaire. COPD subjects were more likely to report comorbidities (55.2%) than subjects without COPD (39.1%, P<0.0001), most frequently cardiovascular diseases. In subjects who screened positively for COPD, the presence of comorbidities was significantly (P=0.03) associated with a COPD Assessment Test score ≥10 and with antecedents of COPD exacerbations in the previous 6 months (P=0.03). Conclusion Comorbidities are frequent in COPD and associated with more severe respiratory symptoms. This highlights the importance of identification and appropriate management of comorbidities in all subjects with a diagnosis of COPD. PMID:26917957

  15. Women of the World: Near East and North Africa.

    ERIC Educational Resources Information Center

    Chamie, Mary

    The third in a series of five handbooks designed to present and analyze statistical data on women in various regions of the world, this handbook focuses on women in 14 countries in the Near East and North Africa. Beginning with an overview of population distribution and changes in the region, the analysis continues with a description of women's…

  16. The Impact of Human Activities in Africa, the North and South Pole Regions on Global Climate Change.

    NASA Astrophysics Data System (ADS)

    Abubakar, B.

    2007-05-01

    a way that goals could be achieved without necessarily causing problems to the world climate. 4. The International Maritime Organization (IMO) should check and control the Ocean Pollutions caused as a result of the degreasing activities of the "QUAY APRONS" currently going on at the various African Sea Ports in order to protect the Ocean pollution with chemicals that can make the World's ice to be melting. 5. The International Meteorological Organization should open its offices within each region of the six continents in order to have a closer monitoring of human activities that can influence the world's climate. Organizing seminars, Conferences and Workshops on a regular basis by the United Nations and other related organizations can help in the areas of public enlightenment and the education of the rural populace who are also great contributors to the situation. The UN should use its capacity to discourage the importation of fairly used refrigerators, Air-conditioners and propellants to Africa and at the same time assist in the subsidy of the newer ones coming to Africa, so that the average African can afford buying them I believe that if the above listed suggestions/recommendations are adopted and implemented it will help in reducing these challenges threatening the entire world. Thanks for listening.

  17. The impact of human activities in africa,the north and south pole regions on global climate change

    NASA Astrophysics Data System (ADS)

    Abubakar, Babagana

    a way that goals could be achieved without necessarily causing problems to the world climate. 4. The International Maritime Organization (IMO) should check and control the Ocean Pollutions caused as a result of the degreasing activities of the "QUAY APRONS" currently going on at the various African Sea Ports in order to protect the Ocean pollution with chemicals that can make the World's ice to be melting. 5. The International Meteorological Organization should open its offices within each region of the six continents in order to have a closer monitoring of human activities that can influence the world's climate. 6. Organizing seminars, Conferences and Workshops on a regular basis by the United Nations and other related organizations can help in the areas of public enlightenment and the education of the rural populace who are also great contributors to the situation. 7. The UN should use its capacity to discourage the importation of fairly used refrigerators, Air-conditioners and propellants to Africa and at the same time assist in the subsidy of the newer ones coming to Africa, so that the average African can afford buying them I believe that if the above listed suggestions/recommendations are adopted and implemented it will help in reducing these challenges threatening the entire world. Thanks for listening.

  18. The case for developing publicly-accessible datasets for health services research in the Middle East and North Africa (MENA) region

    PubMed Central

    Saleh, Shadi S; Alameddine, Mohamad S; El-Jardali, Fadi

    2009-01-01

    Background The existence of publicly-accessible datasets comprised a significant opportunity for health services research to evolve into a science that supports health policy making and evaluation, proper inter- and intra-organizational decisions and optimal clinical interventions. This paper investigated the role of publicly-accessible datasets in the enhancement of health care systems in the developed world and highlighted the importance of their wide existence and use in the Middle East and North Africa (MENA) region. Discussion A search was conducted to explore the availability of publicly-accessible datasets in the MENA region. Although datasets were found in most countries in the region, those were limited in terms of their relevance, quality and public-accessibility. With rare exceptions, publicly-accessible datasets - as present in the developed world - were absent. Based on this, we proposed a gradual approach and a set of recommendations to promote the development and use of publicly-accessible datasets in the region. These recommendations target potential actions by governments, researchers, policy makers and international organizations. Summary We argue that the limited number of publicly-accessible datasets in the MENA region represents a lost opportunity for the evidence-based advancement of health systems in the region. The availability and use of publicly-accessible datasets would encourage policy makers in this region to base their decisions on solid representative data and not on estimates or small-scale studies; researchers would be able to exercise their expertise in a meaningful manner to both, policy makers and the public. The population of the MENA countries would exercise the right to benefit from locally- or regionally-based studies, versus imported and in 'best cases' customized ones. Furthermore, on a macro scale, the availability of regionally comparable publicly-accessible datasets would allow for the exploration of regional variations

  19. ERTS-1 imagery as an aid to the understanding of the regional setting of base metal deposits in the North West Cape Province, South Africa. [mineral exploration

    NASA Technical Reports Server (NTRS)

    Viljoen, R. P.

    1974-01-01

    A number of base metal finds have recently focussed attention on the North Western Cape Province of South Africa as an area of great potential mineral wealth. From the point of view of competitive mineral exploration it was essential that an insight into the regional geological controls of the base metal mineralization of the area be obtained as rapidly as possible. Conventional methods of producing a suitable regional geological map were considered to be too time-consuming and ERTS-1 imagery was consequently examined. This imagery has made a significant contribution in the compilation of a suitable map on which to base further mineral exploration programmes. The time involved in the compilation of maps of this nature was found to be only a fraction of the time necessary for the production of similar maps using other methods. ERTS imagery is therefore considered to be valuable in producing accurate regional maps in areas where little or no geological data are available, or in areas of poor access. Furthermore, these images have great potential for rapidly defining the regional extent of metallogenic provinces.

  20. Genetic diversity and admixture of indigenous cattle from North Ethiopia: implications of historical introgressions in the gateway region to Africa.

    PubMed

    Zerabruk, M; Li, M-H; Kantanen, J; Olsaker, I; Ibeagha-Awemu, E M; Erhardt, G; Vangen, O

    2012-06-01

    Microsatellite variation was surveyed to determine the genetic diversity, population structure and admixture of seven North Ethiopian cattle breeds by combining multiple microsatellite data sets of Indian and West African zebu, and European, African and Near-Eastern taurine in genetic analyses. Based on allelic distribution, we identified four diagnostic alleles (HEL1-123 bp, CSSM66-201 bp, BM2113-150 bp and ILSTS6-285 bp) specific to the Near-Eastern taurine. Results of genetic relationship and population structure analyses confirmed the previously established marked genetic distinction between taurine and zebu, and indicated further divergence among the bio-geographical groupings of breeds such as North Ethiopian, Indian and West African zebu, and African, European and Near-Eastern taurine. Using the diagnostic alleles for bio-geographical groupings and a Bayesian method for population structure inference, we estimated the genetic influences of major historical introgressions in North Ethiopian cattle. The breeds have been heavily (>90%) influenced by zebu, followed by African, European and the Near-Eastern taurine. Overall, North Ethiopian cattle show a high level of within-population genetic variation (e.g. observed heterozygosity = 0.659-0.687), which is in the upper range of that reported for domestic cattle and indicates their potential for future breeding applications, even in a global context. Rather low but significant population differentiation (F(ST) = 1.1%, P < 0.05) was recorded as a result of multiple introgression events and strong genetic exchanges among the North Ethiopian breeds. PMID:22486496

  1. High temperature solar thermal technology: The North Africa Market

    SciTech Connect

    Not Available

    1990-12-01

    High temperature solar thermal (HTST) technology offers an attractive option for both industrialized and non-industrialized countries to generate electricity and industrial process steam. The purpose of this report is to assess the potential market for solar thermal applications in the North African countries of Algeria, Egypt, Morocco and Tunisia. North Africa was selected because of its outstanding solar resource base and the variety of applications to be found there. Diminishing oil and gas resources, coupled with expanding energy needs, opens a large potential market for the US industry. The US high temperature solar trough industry has little competition globally and could build a large market in these areas. The US is already familiar with certain solar markets in North Africa due to the supplying of substantial quantities of US-manufactured flat plate collectors to this region.

  2. Human immunodeficiency virus and viral hepatitis among high-risk groups: Understanding the knowledge gap in the Middle East and North Africa Region

    PubMed Central

    Melhem, Nada M; Rahhal, Nour; Charide, Rana; Kreidieh, Khalil; El-Khatib, Rolla

    2015-01-01

    AIM: To identify gaps in the existing knowledge on single, dual and triple infections of human immunodeficiency virus (HIV), hepatitis B virus (HBV) and hepatitis C virus (HCV) in the Middle East and North Africa (MENA) region among men who have sex with men (MSMs), female sex workers (FSWs), injecting drug users (IDUs) and prisoners. METHODS: We performed an extensive literature search on articles published on the topic in the 25 countries of the MENA region. PubMed database was used as the main search engine. Case reports, case series, qualitative studies, editorials, commentaries, authors’ replies and animal studies were excluded. Original articles and reviews dealing with the prevalence of HIV, HBV and HCV and their co-infection were included. Data on population type, sample size, age and markers of infections were extracted from the relevant studies. RESULTS: HIV, HBV and HCV are blood-borne viruses with similar modes of transmission. The categories of people at high risk of acquiring HIV-1, HBV and HCV commonly include: MSMs, FSW and IDUs. It is well established that HIV-positive individuals co-infected with HBV or HCV suffer from liver pathology associated with morbidity and mortality. Moreover, HIV-infected individuals do not respond well to treatment for HBV or HCV and hence are at increased risk of hepatic toxicity. Consequently, co-infection of HIV-positive individuals with HBV and/or HCV is a global health problem of significant magnitude. Our review reveals the paucity of epidemiological data for key populations in many countries of the region. Limited number of studies exists in the MENA region on the status of HIV, HBV and HCV and their co-infections among prisoners, MSMs and FSWs. Evidence support the continued increase of the HIV epidemic among MSMs. In addition to the lack of studies on MSMs and FSWs in the MENA region, our review highlights the lack of data on the practices, characteristics, or the status of HIV infection and viral hepatitis

  3. QTL for yield and associated traits in the Seri/Babax population grown across several environments in Mexico, in the West Asia, North Africa, and South Asia regions.

    PubMed

    Lopes, Marta S; Reynolds, Matthew P; McIntyre, C Lynne; Mathews, Ky L; Jalal Kamali, M R; Mossad, Moussa; Feltaous, Yousef; Tahir, Izzat S A; Chatrath, Ravish; Ogbonnaya, Francis; Baum, Michael

    2013-04-01

    Heat and drought adaptive quantitative trait loci (QTL) in a spring bread wheat population resulting from the Seri/Babax cross designed to minimize confounding agronomic traits have been identified previously in trials conducted in Mexico. The same population was grown across a wide range of environments where heat and drought stress are naturally experienced including environments in Mexico, West Asia, North Africa (WANA), and South Asia regions. A molecular genetic linkage map including 475 marker loci associated to 29 linkage groups was used for QTL analysis of yield, days to heading (DH) and to maturity (DM), grain number (GM2), thousand kernel weight (TKW), plant height (PH), canopy temperature at the vegetative and grain filling stages (CTvg and CTgf), and early ground cover. A QTL for yield on chromosome 4A was confirmed across several environments, in subsets of lines with uniform allelic expression of a major phenology QTL, but not independently from PH. With terminal stress, TKW QTL was linked or pleiotropic to DH and DM. The link between phenology and TKW suggested that early maturity would favor the post-anthesis grain growth periods resulting in increased grain size and yields under terminal stress. GM2 and TKW were partially associated with markers at different positions suggesting different genetic regulation and room for improvement of both traits. Prediction accuracy of yield was improved by 5 % when using marker scores of component traits (GM2 and DH) together with yield in multiple regression. This procedure may provide accumulation of more favorable alleles during selection. PMID:23269228

  4. Hepatitis C Virus in North Africa: An Emerging Threat

    PubMed Central

    El-Bouzedi, Abdallah; Dau, Aghnyia A.; Agnan, Mohamed M.

    2016-01-01

    Hepatitis C virus is a major public health threat associated with serious clinical consequences worldwide. North Africa is a unique region composed of seven countries that vary considerably in the predisposing factors to microbial diseases both historically and at the present time. The dynamics of HCV in the region are not well documented. The data are both limited and controversial in most of the countries in the region. In North Africa, the epidemiology of HCV is disparate and understanding it has been hampered by regional “epidemiological homogeneity” concepts. As the dynamics of HCV vary from country to country, context-specific research is needed. In this review, we assess studies performed in each country in the general populations as well as among blood donors and groups exposed to the HCV infection. The reported prevalence of HCV ranges from 0.6% to 8.4% in the Maghreb countries and is predominated by genotype 1. In the Nile valley region, it ranges from 2.2% to 18.9% and is dominated by genotype 4. In North African countries, HCV seems to be a serious problem that is driven by different vectors even in different geographical locations within the same country. Efforts should be combined at both the national and regional levels to implement efficient preventive and treatment strategies. PMID:27610403

  5. Hepatitis C Virus in North Africa: An Emerging Threat.

    PubMed

    Daw, Mohamed A; El-Bouzedi, Abdallah; Ahmed, Mohamed O; Dau, Aghnyia A; Agnan, Mohamed M

    2016-01-01

    Hepatitis C virus is a major public health threat associated with serious clinical consequences worldwide. North Africa is a unique region composed of seven countries that vary considerably in the predisposing factors to microbial diseases both historically and at the present time. The dynamics of HCV in the region are not well documented. The data are both limited and controversial in most of the countries in the region. In North Africa, the epidemiology of HCV is disparate and understanding it has been hampered by regional "epidemiological homogeneity" concepts. As the dynamics of HCV vary from country to country, context-specific research is needed. In this review, we assess studies performed in each country in the general populations as well as among blood donors and groups exposed to the HCV infection. The reported prevalence of HCV ranges from 0.6% to 8.4% in the Maghreb countries and is predominated by genotype 1. In the Nile valley region, it ranges from 2.2% to 18.9% and is dominated by genotype 4. In North African countries, HCV seems to be a serious problem that is driven by different vectors even in different geographical locations within the same country. Efforts should be combined at both the national and regional levels to implement efficient preventive and treatment strategies. PMID:27610403

  6. Modeling the distribution of the West Nile and Rift Valley Fever vector Culex pipiens in arid and semi-arid regions of the Middle East and North Africa

    PubMed Central

    2014-01-01

    Background The Middle East North Africa (MENA) region is under continuous threat of the re-emergence of West Nile virus (WNV) and Rift Valley Fever virus (RVF), two pathogens transmitted by the vector species Culex pipiens. Predicting areas at high risk for disease transmission requires an accurate model of vector distribution, however, most Cx. pipiens distribution modeling has been confined to temperate, forested habitats. Modeling species distributions across a heterogeneous landscape structure requires a flexible modeling method to capture variation in mosquito response to predictors as well as occurrence data points taken from a sufficient range of habitat types. Methods We used presence-only data from Egypt and Lebanon to model the population distribution of Cx. pipiens across a portion of the MENA that also encompasses Jordan, Syria, and Israel. Models were created with a set of environmental predictors including bioclimatic data, human population density, hydrological data, and vegetation indices, and built using maximum entropy (Maxent) and boosted regression tree (BRT) methods. Models were created with and without the inclusion of human population density. Results Predictions of Maxent and BRT models were strongly correlated in habitats with high probability of occurrence (Pearson’s r = 0.774, r = 0.734), and more moderately correlated when predicting into regions that exceeded the range of the training data (r = 0.666,r = 0.558). All models agreed in predicting high probability of occupancy around major urban areas, along the banks of the Nile, the valleys of Israel, Lebanon, and Jordan, and southwestern Saudi Arabia. The most powerful predictors of Cx. pipiens habitat were human population density (60.6% Maxent models, 34.9% BRT models) and the seasonality of the enhanced vegetation index (EVI) (44.7% Maxent, 16.3% BRT). Maxent models tended to be dominated by a single predictor. Areas of high probability corresponded with sites of

  7. Association between dietary pattern and risk of cardiovascular disease among adults in the Middle East and North Africa region: a systematic review

    PubMed Central

    Aljefree, Najlaa; Ahmed, Faruk

    2015-01-01

    Objective This paper reviews the evidence related to the association of dietary pattern with coronary heart disease (CHD), strokes, and the associated risk factors among adults in the Middle East and North Africa (MENA) region. Methods A systematic review of published articles between January 1990 and March 2015 was conducted using Pro-Quest Public Health, MEDLINE, and Google Scholar. The term ‘dietary pattern’ refers to data derived from dietary pattern analyses and individual food component analyses. Results The search identified 15 studies. The available data in the MENA region showed that Western dietary pattern has been predominant among adults with fewer adherences to the traditional diet, such as the Mediterranean diet. The Western dietary pattern was found to be associated with an increased risk of dyslipidaemia, diabetes, metabolic syndrome (MetS), body mass index (BMI), and hypertension. The Mediterranean diet, labelled in two studies as ‘the traditional Lebanese diet’, was negatively associated with BMI, waist circumference (WC), and the risk of diabetes, while one study found no association between the Mediterranean diet and MetS. Two randomised controlled trials conducted in Iran demonstrated the effect of the dietary approach to stop hypertension (DASH) in reducing metabolic risk among patients with diabetes and MetS. Likewise, the consumption of dairy products was associated with decreased blood pressure and WC, while the intake of whole grains was associated with reduced WC. In addition, the high consumption of black tea was found to be associated with decreased serum lipids. The intake of fish, vegetable oils, and tea had a protective effect on CHD, whereas the intake of full-fat yoghurt and hydrogenated fats was associated with an increased risk of CHD. Conclusion There appears to be a significant association of Western dietary pattern with the increased risk of CHD, strokes, and associated risk factors among adults in the MENA region

  8. Neo-deterministic seismic hazard assessment in North Africa

    NASA Astrophysics Data System (ADS)

    Mourabit, T.; Abou Elenean, K. M.; Ayadi, A.; Benouar, D.; Ben Suleman, A.; Bezzeghoud, M.; Cheddadi, A.; Chourak, M.; ElGabry, M. N.; Harbi, A.; Hfaiedh, M.; Hussein, H. M.; Kacem, J.; Ksentini, A.; Jabour, N.; Magrin, A.; Maouche, S.; Meghraoui, M.; Ousadou, F.; Panza, G. F.; Peresan, A.; Romdhane, N.; Vaccari, F.; Zuccolo, E.

    2014-04-01

    North Africa is one of the most earthquake-prone areas of the Mediterranean. Many devastating earthquakes, some of them tsunami-triggering, inflicted heavy loss of life and considerable economic damage to the region. In order to mitigate the destructive impact of the earthquakes, the regional seismic hazard in North Africa is assessed using the neo-deterministic, multi-scenario methodology (NDSHA) based on the computation of synthetic seismograms, using the modal summation technique, at a regular grid of 0.2 × 0.2°. This is the first study aimed at producing NDSHA maps of North Africa including five countries: Morocco, Algeria, Tunisia, Libya, and Egypt. The key input data for the NDSHA algorithm are earthquake sources, seismotectonic zonation, and structural models. In the preparation of the input data, it has been really important to go beyond the national borders and to adopt a coherent strategy all over the area. Thanks to the collaborative efforts of the teams involved, it has been possible to properly merge the earthquake catalogues available for each country to define with homogeneous criteria the seismogenic zones, the characteristic focal mechanism associated with each of them, and the structural models used to model wave propagation from the sources to the sites. As a result, reliable seismic hazard maps are produced in terms of maximum displacement ( D max), maximum velocity ( V max), and design ground acceleration.

  9. Petroleum developments in North Africa in 1979

    SciTech Connect

    Nicod, M.A.

    1980-11-01

    In the 6 countries covered by this report, the extent of valid petroleum rights, seismic work, and drilling was nearly the same as in 1978. The success rate of wildcat drilling decreased slightly, to 28% (33% in 1978), with 26 oil or gas discoveries. In southwestern Tunisia, the Amoco Sabrina Nord 1 tested 930 bbl of 39/sup 0/ APl oil from Cambrian-Ordovician sandstones - the first oil to come from lower Paleozoic rocks in Tunisia. First commercial oil from Cambrian-Ordovician rocks in western Libya was discovered by Agip A1-NC40 which flowed 1,400 b/d. Highlight of the year in North Africa was in the interior basin of Sudan where the Chevron Abu Gabra 1 tested 900 BOPD of 40/sup 0/ APl oil from Cretaceous rocks; 2 other wells, spudded in late 1979 in the same area, have tested 3,200 and 7,300 b/d, respectively, in early 1980. Discovery well of the interior basin was Chevron Unity 1 which tested small amounts of oil in 1978. Oil production in North Africa in 1979 averaged 3,939,500 b/d compared with 3,802,800 b/d in 1978, an increase of 3.6%.

  10. Institutional Research in Emerging Countries of Southern Africa, Latin America, and the Middle East and North Africa: Global Frameworks and Local Practices

    ERIC Educational Resources Information Center

    Lange, Lis; Saavedra, F. Mauricio; Romano, Jeanine

    2013-01-01

    This chapter presents a synthesis of the conceptualization and practice of institutional research (IR) in higher education (HE) in emerging countries across Southern Africa, Latin America and the Middle East and North Africa (MENA) regions. The chapter contextualizes the growing need for IR in these regions, identifies problems and challenges…

  11. Atmospheric predictors for annual maximum precipitation in North Africa

    NASA Astrophysics Data System (ADS)

    Nasri, Bouchra

    2015-04-01

    The high precipitation variability over North Africa presents a major challenge for the population and the infrastructures in the region. The last decades have seen many flood events caused by extreme precipitation occurring in this area. Prior to the development of downscaling models to evaluate the possible climate change impacts on extreme precipitation, there is a need to identify the most relevant atmospheric predictors to model these extreme events. In this work, the effect of 14 different variables calculated from NCEP reanalyses from daily to seasonal time steps on the maximal annual daily precipitation (MAP) is evaluated at 6 coastal stations located in North Africa (Larache, Tangiers, Mellila, Algiers, Tunis and Gabes). The GEV-B-Spline model has been used to detect this influence. This model considers all dependence forms (linear, quadratic..) between the covariates and the variable of interest thus providing a very flexible framework to evaluate the covariate effects on the GEV model parameters. The estimation of the parameters of GEV-B-Spline model is done in a Bayesian framework. A Markov Chain Monte Carlo (MCMC) algorithm has been developed to estimate quantiles and their posterior distributions. The results show that not a single set of covariates is valid for all stations. Overall a strong dependence between the NCEP covariates and MAP is detected, in particular with covariates describing large scale circulation (geopotential heights) or moisture (humidity). Therefore this study provides insights for developing downscaling models for extreme precipitation tailored for North African conditions.

  12. The Regionalization of Africa: Delineating Africa's Subregions Using Airline Data

    ERIC Educational Resources Information Center

    Good, Pieter R.; Derudder, Ben; Witlox, Frank J.

    2011-01-01

    Current regionalizations of Africa have limitations in that they are attribute-based and regions are delineated according to national boundaries. Taking the world city network approach as starting point, it is possible to use relational data (i.e., information about the relationships between cities) rather than attribute data, and moreover, it…

  13. Genome-Wide and Paternal Diversity Reveal a Recent Origin of Human Populations in North Africa

    PubMed Central

    Martínez-Cruz, Begoña; Zalloua, Pierre; Benammar Elgaaied, Amel; Comas, David

    2013-01-01

    The geostrategic location of North Africa as a crossroad between three continents and as a stepping-stone outside Africa has evoked anthropological and genetic interest in this region. Numerous studies have described the genetic landscape of the human population in North Africa employing paternal, maternal, and biparental molecular markers. However, information from these markers which have different inheritance patterns has been mostly assessed independently, resulting in an incomplete description of the region. In this study, we analyze uniparental and genome-wide markers examining similarities or contrasts in the results and consequently provide a comprehensive description of the evolutionary history of North Africa populations. Our results show that both males and females in North Africa underwent a similar admixture history with slight differences in the proportions of admixture components. Consequently, genome-wide diversity show similar patterns with admixture tests suggesting North Africans are a mixture of ancestral populations related to current Africans and Eurasians with more affinity towards the out-of-Africa populations than to sub-Saharan Africans. We estimate from the paternal lineages that most North Africans emerged ∼15,000 years ago during the last glacial warming and that population splits started after the desiccation of the Sahara. Although most North Africans share a common admixture history, the Tunisian Berbers show long periods of genetic isolation and appear to have diverged from surrounding populations without subsequent mixture. On the other hand, continuous gene flow from the Middle East made Egyptians genetically closer to Eurasians than to other North Africans. We show that genetic diversity of today's North Africans mostly captures patterns from migrations post Last Glacial Maximum and therefore may be insufficient to inform on the initial population of the region during the Middle Paleolithic period. PMID:24312208

  14. NORTH ALBEMARLE REGION HYDROGEOLOGIC FRAMEWORK

    EPA Science Inventory

    The North Albemarle region lies north of the Albemarle Sound and east of the Chowan River, including Camden, Chowan, Currituck, Gates, Pasquotank, and Perquimans Counties. This area is in great need of additional water sources in order to accommodate a growing population spilling...

  15. Astronomy in the Middle East and North Africa

    NASA Astrophysics Data System (ADS)

    Athem Alsabti, Abdul

    2015-08-01

    Recent turbulent events in the Middle East and North Africa have influenced all aspects of life. Education in general, including astronomy, teaching and research has all been greatly affected. In this presentation, the current situation regarding astronomy in this region is reviewed in detail. This is based on visits made to Tunisia and Algeria recently on behalf of the IAU and other visits to Iraq, Qatar, Egypt and Jordan in recent years, as well as on discussions and communications with astronomers, officials and astronomical and educational institutes in the region. Discussions have also been established with astronomers from Iran, Oman and Morocco. Ideas and proposals will be presented on the best ways for the IAU and the international academic community to help under these circumstances.

  16. Climate Variability and Predictability in North West Africa

    NASA Astrophysics Data System (ADS)

    Baddour, O.; Djellouli, Y.

    2003-04-01

    North West Africa defined here as the area including Morocco, Algeria and Tunisia, it occupies a large territory in North Africa with more than 3.5 Millions KM2. The geographical contrast is very important: while most of the southern part is desert, the northern and north western part exhibits a contrasting geography including large flat areas in the western part of Morocco, northern Algeria and eastern part of Tunisia, And also the formidable Atlas mountains barrier that extends from south west of Morocco toward north west of Tunisia crossing central Morocco and north Algeria.Agriculture is one of major socio-economic activity in the region with an extensive cash-crop for exporting to Europe especially from Morocco and Tunisia. The influence of the recurring droughts during 80s and 90s was very crucial for the economic and societal aspects of the region. In Morocco, severe droughts has caused GDP fluctuation within past 20 years from 10% increase down to negative values in some particular years. Most of weather systems occurs during frontal excursion through the Atlantic and Europe bringing cold air and cloud and precipitation systems. The active precipitation period extends from October to May with almost 80% of the total rainfall. The dry season extends from June to September. Nevertheless some convective clouds develop occasionally during the dry season due to subtropical humid air mass that converge into the region and trigger the convection especially in the high area and Sahara. These less frequent precipitation systems could lead to weather hazards such as flash floods with damage to population and infrastructure. (The example of OURIKA in August 1995 in Morocco). The far south of the region experiences some tropical influence during August period especially in the south of Algeria when the ITCZ can migrate from the SAHEL area to its northernmost position in the region. Recent studies have investigated seasonal rainfall variability and prediction over

  17. Analysis of drought events in a North Africa semi-arid region, Using SPOT-VEGETATION and C band scatterometer satellite Data

    NASA Astrophysics Data System (ADS)

    Zribi, M.; Amri, R.; Lili-Chabaane, Z.; Wagner, W.; Hasenauer, S.; Duchemin, B.; Boulet, G.; Mougenot, B.

    2012-04-01

    In semi-arid regions, and northern Africa in particular, the scarcity of rainfall and the occurrence of long periods of drought, represent one of the main environmental factors having a negative effect on agricultural productivity. This is the case in Central Tunisia, where the monitoring of agricultural and water resources is of prime importance. Vegetation cover and soil moisture are key parameters in this objective. Remote sensing has shown in the last decades a high potential to estimate these surface parameters. This study is based on two satellite products: SPOT-VEGETATION NDVI data and ERS and ASCAT/METOP moisture products proposed by Vienna University of Technology (TU Wien) (Wagner et al., 1999). A validation of soil moisture products is realized over the studied site using ground measurements (Thetaprobe continuous measurements), inter-comparison with other satellite products and precipitation levels. Based on long time series of satellite products, two anomaly indices have been proposed. In order to estimate the state of stress of the vegetation cover, an index referred to as the Vegetation Anomaly Index (VAI) is proposed from SPOT-VGT time series. A positive VAI indicates good vegetation dynamics, whereas a negative VAI indicates the presence of vegetation stress. This index is highly correlated to precipitation, and is found to have a maximum correlation with the 4-month cumulative precipitation (CP3). The VAI index can be operationally applied in order to estimate quantitatively the effect of drought on vegetation cover. Based on SWI (Soil Water Index) products, representing root-zone soil moisture content in the first meter of the soil, we propose a simple Moisture Anomaly Index, which can provide a quantitative visualization of drought periods. This index is compared with and validated, using the SPI precipitation index. A high degree of correlation is observed between the two indices. The Moisture Anomaly Index could be a very useful tool in

  18. Evaluating the Old World Drought Atlas in North Africa

    NASA Astrophysics Data System (ADS)

    Touchan, Ramzi; Kherchouche, Dalila; Anchukaitis, Kevin; Slimani, Said; Krcmaric, Jordan A.; Meko, David M.

    2016-04-01

    Drought is a focal point in the assessment of hydroclimatic variability in the Mediterranean Basin. The Old World Drought Atlas (OWDA) by Cook et al. (2015) was the starting point for understanding several centuries of drought occurrence, duration, and severity over all of Europe including the Mediterranean Basin. Here, we investigate the extension of the OWDA to North Africa (NA), specifically Algeria, since droughts there can have drastic social and economic impacts. Pearson correlations were used to gauge strength of the relationship of gridded reconstructed series from OWDA (-0.25° W-34°.25N, 34°.75N, 35°.25N, and 35°.75N) with 27 tree-ring chronologies from various species from Algeria. Correlations range from 0.35 (p < 0.0001) to 0.025 (p >0.627), and suggest the OWDA does not fully reflect the regional drought patterns in parts of Algeria and nearby NA. Lower correlations between local tree-ring chronologies and OWDA grids are related to the lack of tree-ring chronologies from Algeria within the OWDA. Work is ongoing to blend existing chronologies from the Mediterranean region with newly developed chronologies from currently under-sampled parts of NA and generate a Mediterranean Basin Drought Atlas (MBDA) that chronicles spatiotemporal drought variability over the past few centuries to millennium. The MBDA will complement the OWDA, the existing 'North American Drought Atlas' (NADA), and the 'Monsoon Asia Drought Atlas' (MADA) in charting drought history of the Northern Hemisphere.

  19. Regional Climate Change Hotspots over Africa

    NASA Astrophysics Data System (ADS)

    Anber, U.; Zakey, A.; Abd El Wahab, M.

    2009-04-01

    Regional Climate Change Index (RCCI), is developed based on regional mean precipitation change, mean surface air temperature change, and change in precipitation and temperature interannual variability. The RCCI is a comparative index designed to identify the most responsive regions to climate change, or Hot- Spots. The RCCI is calculated for Seven land regions over North Africa and Arabian region from the latest set of climate change projections by 14 global climates for the A1B, A2 and B1 IPCC emission scenarios. The concept of climate change can be approaches from the viewpoint of vulnerability or from that of climate response. In the former case a Hot-Spot can be defined as a region for which potential climate change impacts on the environment or different activity sectors can be particularly pronounced. In the other case, a Hot-Spot can be defined as a region whose climate is especially responsive to global change. In particular, the characterization of climate change response-based Hot-Spot can provide key information to identify and investigate climate change Hot-Spots based on results from multi-model ensemble of climate change simulations performed by modeling groups from around the world as contributions to the Fourth Assessment Report of Intergovernmental Panel on Climate Change (IPCC). A Regional Climate Change Index (RCCI) is defined based on four variables: change in regional mean surface air temperature relative to the global average temperature change ( or Regional Warming Amplification Factor, RWAF ), change in mean regional precipitation (P % , of present day value ), change in regional surface air temperature interannual variability (T % ,of present day value), change in regional precipitation interannual variability (P % ,of present day value ). In the definition of the RCCI it is important to include quantities other than mean change because often mean changes are not the only important factors for specific impacts. We thus also include inter

  20. Regional Climate Change Hotspots over Africa

    NASA Astrophysics Data System (ADS)

    Anber, U.

    2009-04-01

    Regional Climate Change Index (RCCI), is developed based on regional mean precipitation change, mean surface air temperature change, and change in precipitation and temperature interannual variability. The RCCI is a comparative index designed to identify the most responsive regions to climate change, or Hot- Spots. The RCCI is calculated for Seven land regions over North Africa and Arabian region from the latest set of climate change projections by 14 global climates for the A1B, A2 and B1 IPCC emission scenarios. The concept of climate change can be approaches from the viewpoint of vulnerability or from that of climate response. In the former case a Hot-Spot can be defined as a region for which potential climate change impacts on the environment or different activity sectors can be particularly pronounced. In the other case, a Hot-Spot can be defined as a region whose climate is especially responsive to global change. In particular, the characterization of climate change response-based Hot-Spot can provide key information to identify and investigate climate change Hot-Spots based on results from multi-model ensemble of climate change simulations performed by modeling groups from around the world as contributions to the Assessment Report of Intergovernmental Panel on Climate Change (IPCC). A Regional Climate Change Index (RCCI) is defined based on four variables: change in regional mean surface air temperature relative to the global average temperature change ( or Regional Warming Amplification Factor, RWAF ), change in mean regional precipitation ( , of present day value ), change in regional surface air temperature interannual variability ( ,of present day value), change in regional precipitation interannual variability ( , of present day value ). In the definition of the RCCI it is important to include quantities other than mean change because often mean changes are not the only important factors for specific impacts. We thus also include inter annual

  1. Differences in Reliability of Reproductive History Recall among Women in North Africa

    ERIC Educational Resources Information Center

    Soliman, Amr; Allen, Katharine; Lo, An-Chi; Banerjee, Mousumi; Hablas, Ahmed; Benider, Abdellatif; Benchekroun, Nadya; Samir, Salwa; Omar, Hoda G.; Merajver, Sofia; Mullan, Patricia

    2009-01-01

    Breast cancer is the most common cancer among women in North Africa. Women in this region have unique reproductive profiles. It is essential to obtain reliable information on reproductive histories to help better understand the relationship between reductive health and breast cancer. We tested the reliability of a reproductive history-based…

  2. Near East and North Africa: A Question Syllabus. Center for Area and Country Studies.

    ERIC Educational Resources Information Center

    Howard, Harry N.

    This study syllabus on the Near East and North Africa is divided into twelve units. Designed to familiarize government personnel assigned to the area with the region and people, each unit consists of a statement of the main objectives to be studied, questions for consideration, and a list of suggested readings from books and periodicals. Units…

  3. Space Radar Image of Safsaf, North Africa

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This is a false-color image of the uninhabited Safsaf Oasis in southern Egypt near the Egypt/Sudan border. It was produced from data obtained from the L-band and C-band radars that are part of the Spaceborne Imaging Radar C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) onboard space shuttle Endeavour on April 9, 1994. The image is centered at 22 degree north latitude, 29 degrees east longitude. It shows detailed structures of bedrock; the dark blue sinuous lines are braided channels that occupy part of an old broad river valley. On the ground and in optical photographs, this big valley and the channels in it are invisible because they are entirely covered by windblown sand. Some of these same channels were observed in SIR-A images in 1981. It is hypothesized that the large valley was carved by one of several ancient predecessor rivers that crossed this part of North Africa, flowing westward, tens of millions of years before the Nile River existed. The Nile flows north about 300 kilometers (200 miles) to the east. The small channels are younger, and probably formed during relatively wet climatic periods within the past few hundred thousand years. This image shows that the channels are in a river valley located in an area where U.S. Geological Survey geologists and archeologists discovered an unusual concentration of hand axes (stone tools) used by Early Man (Homo erectus) hundreds of thousands of years ago. The image clearly shows that in wetter times, the valley would have supported game animals and vegetation. Today, as a result of climate change, the area in uninhabited and lacks water except fora few scattered oases. This color composite image was produced from C-band and L-band horizontal polarization images. The C-band image was assigned red, the L-band (HH) polarization image is shown in green, and the ratio of these two images (LHH/CHH) appears in blue. The primary and composite colors on the image indicate the degree to which the C-band, H-band, their

  4. Space Radar Image of Safsaf, North Africa

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This is a false-color image of the uninhabited Safsaf Oasis in southern Egypt near the Egypt/Sudan border. It was produced from data obtained from the L-band and C-band radars that are part of the Spaceborne Imaging Radar C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) onboard space shuttle Endeavour on April 9, 1994. The image is centered at 22 degree north latitude, 29 degrees east longitude. It shows detailed structures of bedrock; the dark blue sinuous lines are braided channels that occupy part of an old broad river valley. On the ground and in optical photographs, this big valley and the channels in it are invisible because they are entirely covered by windblown sand. Some of these same channels were observed in SIR-A images in 1981. It is hypothesized that the large valley was carved by one of several ancient predecessor rivers that crossed this part of North Africa, flowing westward, tens of millions of years before the Nile River existed. The Nile flows north about 300 kilometers (200 miles) to the east. The small channels are younger, and probably formed during relatively wet climatic periods within the past few hundred thousand years. This image shows that the channels are in a river valley located in an area where U.S. Geological Survey geologists and archeologists discovered an unusual concentration of hand axes (stone tools) used by Early Man (Homo erectus) hundreds of thousands of years ago. The image clearly shows that in wetter times, the valley would have supported game animals and vegetation. Today, as a result of climate change, the area in uninhabited and lacks water except fora few scattered oases. This color composite image was produced from C-band and L-band horizontal polarization images. The C-band image was assigned red, the L-band (HH) polarization image is shown in green, and the ratio of these two images (LHH/CHH) appears in blue. The primary and composite colors on the image indicate the degree to which the C-band, H-band, their

  5. Regional paleogeographic evolution of west Africa: Implications for hydrocarbon exploration

    SciTech Connect

    Hempton, M.R.; Rosen, M.A.; Coughlin, R.M.; Scardina, A.D.; Hagen, E.S.; Nordstrom, P.J. )

    1991-03-01

    New paleogeographic reconstructions of west African continental margins provide a regional framework to contrast differences in hydrocarbon habitat and tectonostratigraphic style. Five regional provinces are delineated: (1) Northwest Africa margin from mauritania to Sierra Leone, (2) Transform margin from Liberia to Benin, (3) Niger delta of Nigeria, Cameroon, and Equatorial Guinea, (4) South Atlantic Salt basin margin from Cameroon to Angola, and (5) Southwest Africa margin of Namibia and South Africa. Computer-constrained paleogeographic reconstructions based on exploration data depict the separation of west Africa from South and North America during the Late Triassic to the present along three rift systems. In northwest Africa rifting began in the Late Triassic associated with the opening of the Central Atlantic. In southwest Africa rifting began between the southern tips of Africa and South America in the Early Cretaceous (Valanginian) and propagated northward to the Benue Trough, a broad zone of left-lateral shear and extensional basins that began to open in the Aptian. Between these two rift systems, the Transform margin rift system initiated in the Early Cretaceous (Barremain) as a wrench-fault dominated eastward extension of the Proto-Caribbean ocean that propagated to the Benue Trough by the middle Albian. The most important variables affecting the tectonostratigraphic and hydrocarbon evolution of the west African margins include (1) the geometry, kinematics, and duration of rifting; (2) distribution of rift basins relative to paleoclimate zones (which affects the deposition of lacustrine source rocks and evaporites while influencing the type and quantity of sediment derived from land); (3) sea-level fluctuations; and (4) distribution of deltaic and turbiditic depocenters.

  6. LLNL Middle East and North Africa research database

    SciTech Connect

    Ruppert, S.D.; Hauk, T.F.; Leach, R.

    1997-07-15

    The Lawrence Livermore National Laboratory (LLNL) CTBT R{ampersand}D program has made significant progress assembling a comprehensive seismic database (DB) for events and derived parameters in the Middle East and North Africa (ME/NA). The LLNL research DB provides not only a coherent framework in which store and organize large volumes of collected seismic waveforms and associated event parameter information but also provides an efficient data processing/research environment. The DB is designed to be flexible and extensible in order to accommodate the large volumes of data in diverse formats from many sources in addition to maintaining detailed quality control and metadata. Researchers can make use of the relational nature of the DB and interactive analysis tools to quickly and efficiently process large volumes of data. Seismic waveforms have been systematically collected form a wide range of local and regional networks using numerous earthquake bulletins and converted a common format based on CSS3.O while undergoing quality control and corrections of errors. By combining traveltime observations, event characterization studies, and regional wave-propagation studies of the LLNL CTBT team, we are assembling a library of ground truth information and event location correction surfaces required to support the ME/NA regionalization program. Corrections and parameters distilled from the LLNL research DB will provide needed contributions to the DOE knowledge base for the ME/NA region and enable the USNDC and IDC to effectively verify CTBT compliance.

  7. LLNL Middle East and North Africa research database

    SciTech Connect

    Dodge, D; Hauk, T; Moore, R M; O'Boyle, J; Ruppert, S

    1999-07-23

    The Lawrence Livermore National Laboratory (LLNL) Comprehensive Nuclear-Test-Ban Treaty Research and Development (CTBT R and D) program has made significant progress populating a comprehensive seismic research database (RDB) for seismic events and derived research products in the Middle East and North Africa (MENA). Our original ME/NA study region has enlarged and is now defined as an area including the Middle East, Africa, Europe, Southwest Asia, the Former Soviet Union and the Scandinavian/Arctic region. The LLNL RDB will facilitate calibration of all International Monitoring System (IMS) stations (primary and auxiliary) or their surrogates (if not yet installed) as well as a variety of gamma stations. The RDB provides not only a coherent framework in which to store and organize large volumes of collected seismic waveforms and associated event parameter information, but also provides an efficient data processing/research environment for deriving location and discrimination correction sur faces and capabilities. In order to accommodate large volumes of data from many sources with diverse formats the RDB is designed to be flexible and extensible in addition to maintaining detailed quality control information and associated metadata. Station parameters, instrument responses, phase pick information, and event bulletins were compiled and made available through the RDB. For seismic events in the MENA region occurring between 1976 and 1999, we have systematically assembled, quality checked and organized event waveforms; continuous seismic data from 1990 to present are archived for many stations. Currently, over 11,400 seismic events and 1.2 million waveforms are maintained in the RDB and made readily available to researchers. In addition to open sources of seismic data, we have established collaborative relationships with several ME/NA countries that have yielded additional ground truth and broadband waveform data essential for regional calibration and capability

  8. Aspects of Education in the Middle East and North Africa

    ERIC Educational Resources Information Center

    Brock, Colin, Ed.; Levers, Lila Zia

    2007-01-01

    The chapters in this volume do not represent the whole of the Middle East and North Africa, as such a collection would have been too large for one volume. Rather, the selection here is intended to present different perspectives on a range of educational issues, relevant to a particular focus or country, or common to a number of countries in the…

  9. Perceptions and Images of North Africa: What American Schools Teach.

    ERIC Educational Resources Information Center

    Robinson, Victoria

    2002-01-01

    Examined descriptions of North Africa (particularly Tunisia) found in U.S. high school social studies textbooks, noting the resulting perceptions and images these descriptions created in the minds of teachers and students. Data from examination of textbooks and interviews with teachers indicated that few high school students were exposed to images…

  10. A project of a two meter telescope in North Africa

    NASA Astrophysics Data System (ADS)

    Benkhaldoun, Zouhair

    2015-03-01

    Site testing undertaken during the last 20 years by Moroccan researchers through international studies have shown that the Atlas mountains in Morocco has potentialities similar to those sites which host the largest telescopes in world. Given the quality of the sites and opportunities to conduct modern research, we believe that the installation of a 2m diameter telescope will open new horizons for Astronomy in Morocco and north Africa allowing our region to enter definitively into the very exclusive club of countries possessing an instrument of that size. A state of the art astrophysical observatory on any good astronomical observation site should be equipped with a modern 2m-class, robotic telescope and some smaller telescopes. Our plan should be to operate one of the most efficient robotic 2m class telescopes worldwide in order to offer optimal scientific opportunities for researchers and maintain highest standards for the education of students. Beside all categories of astronomical research fields, students will have the possibility to be educated intensively on the design, manufacturing and operating of modern state of the art computer controlled instruments. In the frame of such education and observation studies several PhD and dissertational work packages are possible. Many of the observations will be published in articles worldwide and a number of guest observers from other countries will have the possibility to take part in collaborations. This could be a starting point of an international reputation of our region in the field of modern astronomy.

  11. Plio-Pleistocene changes in the vegetation of central North Africa

    NASA Astrophysics Data System (ADS)

    Castaneda, I. S.; Phu, V.; Urann, B.

    2013-12-01

    The area of central North Africa (including the Sahara and the Sahel) is sensitive to migrations of the intertropical rainbelt and has experienced dramatic, and possibly abrupt, shifts between wet and arid conditions in the past. For example, during the humid period of the early Holocene, the region that is presently the Sahara desert was vegetated and contained permanent lakes, and was occupied by human populations (e.g. Kuper and Kröpelin, 2006). In this study, we investigate the hydrology of central North Africa during the Plio-Pleistocene (4-0.5 Ma), a period during which a number of key steps in hominin evolution occurred. ODP site 660 is located in the tropical NE Atlantic Ocean (offshore West Africa) and receives dust from central North Africa, which is transported offshore by the African Easterly Jet. Plant leaf waxes (n-alkanes) contained in this dust provide information on the type of vegetation present , which in turn, can be used to examine hydrological variability because in tropical Africa the large scale distribution of vegetation utilizing the C3 (mainly trees) vs. C4 (grasses and warm season sedges) photosynthetic pathways mainly depends on aridity (precipitation) (e.g. Schefuss et al., 2003). Here, we examine the carbon (δ13C) and deuterium (δD) isotopic composition of plant leaf waxes, proxies for vegetation type (C3 vs. C4 plants) and precipitation amount, respectively. We also examine sea surface temperature variability using the alkenone Uk'37 Index as several studies have demonstrated close ties between sea surface temperature variability and hydrological conditions in N Africa during the late Pleistocene and Holocene. Results of this study further support a close link between SST and hydrological conditions in the Sahel during the past 4 Ma while also highlighting regional differences in aridity between Plio-Pleistocene records of western, eastern and southern Africa.

  12. Nitrogen in West Africa: the regional cycle

    SciTech Connect

    Robertson, G.P.; Rosswall, T.

    1986-03-01

    A nitrogen cycle budget has been calculated for West Africa south of the northern Sahara that quantifies biologically important pools of nitrogen in the region and major fluxes associated with these pools. Major compartments of the model include noncultivated systems broken down by vegetation zone, successional status, and plant components, annual and perennial crops each broken down by crop species and plant and harvest components; wetlands; anthropic systems, and soils and sediments. Base reference year is 1978. Biological nitrogen fixation and precipitation fluxes dominated nitrogen inputs to West Africa in 1978. Approximately 12 x 10/sup 9/ kg were fixed in noncultivated systems; about half of this was fixed in early successional (0-6 yr) rain forests, and much of the rest in grazed or fallow savanna grasslands and woodlands. Less than 0.7 x 10/sup 9/ kg were fixed in cultivated systems; legumes accounted for approx. = 25% of this. Total anthropic sources (fossil fuel combustion, fertilizer production, and agricultural commodity imports) were minor (< 0.3 x 10/sup 9/ kg). Precipitation inputs to the region were approx. = 0.4 x 10/sup 9/ kg. Most nitrogen leaving West Africa did so volatilized by fire (approx. = 8.3 x 10/sup 9/ kg), principally in non-cropped systems. Major losses also occurred via hydrologic export to the Atlantic Ocean (1.5 x 10/sup 9/ kg) and via denitrification (1.1 x 10/sup 9/ kg). Total N losses from West Africa exceeded 11.0 x 10/sup 9/ kg. The overall budget balances within 1%, despite independent calculations of all major fluxes. The balance portrays a nitrogen cycle dominated by pools and fluxes in noncropped systems. Indirect human influences, however, mainly through effects on vegetation cover, appear to be a major determinant of both the rates at which nitrogen is cycled in West Africa and the relative importance of most pools and fluxes.

  13. Charophytes as lacustrine biomarkers during the quaternary in North Africa

    NASA Astrophysics Data System (ADS)

    Soulié-Märsche, I.

    The use of charophytes as biomarkers is discussed with emphasis on the differences in study methods for cosmopolitan and ecotype species. A first extensive inventory of Quaternary deposits of charophytes in Africa north of the equator comprising 18 sites from Senegal to the Sudan is drawn up with data on spatial and temporal distribution. The existence of relatively deep cold lakes in the Holocene is shown by the frequent presence of specimens of cold flora no longer present in Africa today. All the original data show the complementary nature of the study of fossil Charophyta for the multidisciplinary reconstitution of palaeoenvironments.

  14. Hypovitaminosis D in the Middle East and North Africa

    PubMed Central

    Bassil, Darina; Rahme, Maya; Hoteit, Maha; Fuleihan, Ghada El-Hajj

    2013-01-01

    Background: The Middle East and North Africa (MENA) region registers some of the highest rates of hypovitaminosis D worldwide.   Aim: We systematically reviewed the prevalence of hypovitaminosis D, rickets and osteomalacia, their predictors and impact on major outcomes, in the region. Methods: Medline, Pubmed and Embase search engines, entering keywords and concepts, combined with individual countries of interest, were used. Search was limited years 2000–2012; and review articles were used for the period preceding year 2000. Results: Rickets and osteomalacia still occur in this sunny region. Hypovitaminosis D prevails, with rates varying 30–90%, considering a desirable serum 25 hydroxy-vitamin D [25(OH)D] of 20 ng/ml. Advancing age, female gender, multi-parity, clothing style, season, socio-economic status and urban living are recognized predictors of hypovitaminosis D in adults. Prolonged breastfeeding without vitamin D supplementation and low dietary calcium intake are the recognized risk factors for rickets and hypovitaminosis D in children.. Associations with pain score and disease activity in rheumatologic disorders, viral load and interleukins in hepatitis C, BMI, lipids and insulin sensitivity, blood pressure, heart failure and mortality are described. Sun exposure in adults decreased prevalence of metabolic syndrome in one study. Few randomized vitamin D trials revealed that the majority of mothers or children failed to achieve a desirable 25(OH)D level, even with doses by far exceeding current recommendations. A trial in adolescent girls reveals substantial bone and lean mass increments. Conclusion: Hypovitaminosis D is prevalent in MENA. The lack of populations based studies, gaps in studies in infants, pre-pubertal children and pregnant women, hinder the development of region specific guidelines and constitute a major obstacle to impact this chronic and most often subclinical disease. PMID:24194968

  15. Event location in the Middle East and North Africa

    SciTech Connect

    Schultz, C.A.; Myers, S.C.; Ruppert, S.D.

    1997-07-01

    The Lawrence Livermore National Laboratory (LLNL) CTBT R{ampersand}D program has made significant progress towards improving the ability of the IMS seismic network to locate small-magnitude events in the Middle East and North Africa (MIYNA). Given that high-grade ground truth (such as known explosions) has been difficult to obtain in these regions, we have placed a significant effort towards the development of a teleseismically constrained seismic database that provides event locations good to within 20m km. This data set is used to make an initial evaluation of the effectiveness of calibration on the proposed seismic IMS network in the MWNA. Utilizing a surrogate IMS regional network in the Middle East we find that when a seismic event lies within the footprint of the recording network the uncalibrated event locations are good to within about 25 km of the teleseismically constrained (TC) location. Using region-specific static station corrections further reduces this difference to about 20 km. To obtain further improvement in location accuracy we have used the modified kriging technique developed by SNL to interpolate new travel-time corrections. We compare this technique withe other robust linear interpolation techniques with the goal of enhancing the estimation of travel-time corrections. This is important to TC events which we find can have large uncorrelated uncertainties. Finally, we are making a large effort to incorporate LLNL analyst picks on primary and secondary phases and develop azimuth and slownsess estimates horn current IMS arrays to improve/supplement the NEIC picks.

  16. Oil and gas developments in North Africa in 1986

    SciTech Connect

    Michel, R.C.

    1987-10-01

    Licensed oil acreage in the 6 North Africa countries (Algeria, Egypt, Libya, Morocco, Sudan and Tunisia) totaled 1,500,000 km/sup 2/ at the end of 1986, down 290,000 km/sup 2/ from 1985. About 50% of the relinquishments were in Libya. Most oil and gas discoveries were made in Egypt (16 oil and 2 gas). Several oil finds were reported in onshore Libya, and 1 was reported in Algeria in the southeastern Sahara. According to available statistics, development drilling decreased from 1985 levels, except in Tunisia. A 6.3% decline in oil production took place in 1986, falling below the 3 million bbl level (2,912,000 b/d). Only sparse data are released on the gas output in North Africa. 6 figures, 27 tables.

  17. Oil and gas developments in north Africa in 1987

    SciTech Connect

    Popescu, B.M.

    1988-10-01

    The recovery of international petroleum activity in 1987 was reflected slightly in the 6 North Africa countries covered in this report (Algeria, Egypt, Libya, Morocco, Sudan, and Tunisia). Licensed area increased marginally to about 2,594,000 km/sup 2/ (up 0.5% from 1986), whereas surface exploration and drilling decreased significantly (about 30% and 20%, respectively, from 1986 levels). The two OPEC-member countries adhered to imposed quotas, recording somewhat lower production levels in 1987 than in 1986; however, total production of the North Africa countries increased to 3,025,000 BOPD (up 2% from 1986) as Egypt recorded all-time highs for both liquids and natural gas production. 7 figs., 29 tabs.

  18. LLNL Middle East, North Africa and Western Eurasia Knowledge Base

    SciTech Connect

    O'Boyle, J; Ruppert, S D; Hauk, T F; Dodge, D A; Ryall, F; Firpo, M A

    2001-07-12

    The Lawrence Livermore National Laboratory (LLNL) Ground-Based Nuclear Event Monitoring (GNEM) program has made significant progress populating a comprehensive Seismic Research Knowledge Base (SRKB) and deriving calibration parameters for the Middle East, North Africa and Western Eurasia (ME/NA/WE) regions. The LLNL SRKB provides not only a coherent framework in which to store and organize very large volumes of collected seismic waveforms, associated event parameter information, and spatial contextual data, but also provides an efficient data processing/research environment for deriving location and discrimination correction surfaces. The SRKB is a flexible and extensible framework consisting of a relational database (RDB), Geographical Information System (GIS), and associated product/data visualization and data management tools. This SRKB framework is designed to accommodate large volumes of data (almost 3 million waveforms from 57,000 events) in diverse formats from many sources (both LLNL derived research and integrated contractor products), in addition to maintaining detailed quality control and metadata. We have developed expanded look-up tables for critical station parameter information (including location and response) and an integrated and reconciled event catalog data set (including specification of preferred origin solutions and associated phase arrivals) for the PDE, CMT, ISC, REB and selected regional catalogs. Using the SRKB framework, we are combining traveltime observations, event characterization studies, and regional tectonic models to assemble a library of ground truth information and phenomenology (e.g. travel-time and amplitude) correction surfaces required for support of the ME/NA/WE regionalization program. We also use the SRKB to integrate data and research products from a variety of sources, such as contractors and universities, to merge and maintain quality control of the data sets. Corrections and parameters distilled from the LLNL SRKB

  19. Cutaneous Leishmaniasis in North Africa: a review

    PubMed Central

    Aoun, Karim; Bouratbine, Aïda

    2014-01-01

    In North African countries, cutaneous leishmaniasis transmission has been increasing since the 1980s, with a significant increase in the incidence of cases and a spread of the geographical distribution. The disease currently represents a major public health problem with a productivity gap and an impediment for development, which results in dramatic socioeconomic and psycho-sanitary impacts. The incidence is more than thousands of cases every year in Algeria, Libya, Morocco, and Tunisia. In Egypt, only a few dozen cases per year are reported, mainly in the Sinai Peninsula. Three Leishmania species, associated with distinct eco-epidemiological and clinical patterns, are involved, namely Leishmania infantum, L. major, and L. tropica. However, L. major is by far the most frequent in Algeria, Libya, and Tunisia, with more than 90% of the registered cases. It is mainly encountered in rural areas under semi-arid, arid and Saharan climates. Leishmania tropica is more prevalent in Morocco, reaching 30–40% of isolates in some districts. Much data is still missing concerning the risk factors of the infection and the lesion development, as well as vector and reservoir ecology and behavior. The knowledge of such parameters, following multidisciplinary and integrated approaches, is crucial for better management and control of the disease, that also faces a lack of resources and efficient control measures. PMID:24626301

  20. Strategies for Female Education in the Middle East and North Africa. Learning for the 21st Century.

    ERIC Educational Resources Information Center

    Rihani, May; Prather, Cynthia J.

    This paper is designed to assist education planners and policymakers in the Middle East and North Africa (MENA) region to identify a range of strategic options to increase the access and retention of girls in the education system. It provides a review of materials relating to the status of female education in the MENA region, statistical data on…

  1. How important are cyclones for emitting mineral dust aerosol in North Africa?

    NASA Astrophysics Data System (ADS)

    Fiedler, S.; Schepanski, K.; Knippertz, P.; Heinold, B.; Tegen, I.

    2013-12-01

    This study presents the first quantitative estimate of the mineral dust emission associated to atmospheric depressions and migrating, long-lived cyclones in North Africa. Results from a tracking algorithm are combined with dust emission flux calculations based on ERA-Interim data from the European Centre for Medium-Range Weather Forecasts for 1989-2008. The results highlight that depressions are abundant and associated with 55% of the dust emission amount annually and spatially averaged over North African dust sources. Even larger contributions to dust emission from depressions are found south of the Atlas Mountains during spring with regionally up to 90%. It is spring when the largest monthly totals of 250-380 g m-2 of dust emission occur in North Africa. The remaining months have a total dust emission smaller than 80 g m-2. In summer, depressions, particularly Saharan heat lows, coincide with up to 90% of the seasonal total dust emission over wide areas of North Africa. In contrast to depressions, migrating cyclones that live for more than two days are rare and are associated to 4% of the annual and spatial dust emission average. Migrating cyclones over North Africa occur primarily in spring north of 20° N with eastwards trajectories and typical life times of three to seven days. Regionally larger seasonal totals of dust emission are associated to cyclones with up to 25% over Libya. In summer, near-surface signatures of African Easterly Waves (AEWs) emit regionally up to 15% of the total emission. The diurnal cycle of dust emission underlines that emission associated to cyclones at mid-day is substantially larger than at night by a factor of three to five. Soil moisture weakens dust emission during cyclone passage by 10%. Despite the overall small contribution of migrating cyclones to dust emission, cyclones coincide with particularly intense dust emission events exceeding the climatological mean flux by a factor of four to eight. This implies, that both

  2. Linking Climate to Incidence of Zoonotic Cutaneous Leishmaniasis (L. major) in Pre-Saharan North Africa

    SciTech Connect

    Bounoua, Lahouari; Kahime, Kholoud; Houti, Leila; Blakey, Tara; Ebi, Kristie L.; Zhang, Ping; Imhoff, Marc L.; Thome, Kurtis; Dudek, Claire; Sahabi, Salah A.; Messouli, Mohammed; Makhlouf, Baghdad; EI Laamrani, Abderahmane; Boumezzough, Ali

    2013-08-20

    Shifts in surface climate may have changed the dynamic of zoonotic cutaneous leishmaniasis (ZCL) in the pre-Saharan zones of North Africa. Caused by Leishmania major, this form multiplies in the body of rodents serving as reservoirs of the disease. The parasite is then transmitted to human hosts by the bite of a Phlebotomine sand fly (Diptera: Psychodidae) that was previously fed by biting an infected reservoir. We examine the seasonal and interannual dynamics of the incidence of this ZCL as a function of surface climate indicators in two regions covering a large area of the semi-arid Pre-Saharan North Africa. Results suggest that in this area, changes in climate may have initiated a trophic cascade that resulted in an increase in ZCL incidence.

  3. Saharan Dust Export towards the Caribbean: Dust Sources and Atmospheric Circulation over North Africa

    NASA Astrophysics Data System (ADS)

    Schepanski, Kerstin; Heinold, Bernd; Groß, Silke; Schäfler, Andreas; Weinzierl, Bernadett; Sauer, Daniel; Walser, Adrian; Tegen, Ina

    2015-04-01

    Studies analysing satellite observations illustrate the spatial and temporal distribution of emitting dust sources. Results show that high surface wind speeds related to the break-down of the nocturnal low-level jet (LLJ) occurring during the morning hours are frequent driving mechanism for dust uplift in the Sahara desert. Here, we present a study investigating atmospheric circulation pattern over North Africa favouring (a) dust entrainment into the boundary layer and (b) dust export towards the Caribbean Sea. Satellite-based information on the spatio-temporal distribution of dust source activation (DSA) events inferred from 15-minute Meteosat Second Generation (MSG) Spinning Enhanced Visible and InfraRed Imager (SEVIRI) dust observations are linked to atmospheric circulation regimes over North Africa. By means of air-mass trajectories, which map the dust export from North Africa toward the SALTRACE ground observation site at Barbados, cases are selected which link DSA regions with dust events observed at Barbados. These cases are then examined with regard to the atmospheric conditions during dust emission and geomorphologic dust source characteristic. Dust properties inferred from LIDAR observation using the POLIS system and measurements taken during Falcon research flights are compared to the different dust source locations and atmospheric conditions during dust emission. Altogether, the results from this study aim at illustrating the relevance of knowing the dust source locations in concert with the atmospheric circulation. Ultimately, this study addresses the question of what is finally transported across the Atlantic towards the Caribbean from which dust source region.

  4. Precipitation Prediction in North Africa Based on Statistical Downscaling

    NASA Astrophysics Data System (ADS)

    Molina, J. M.; Zaitchik, B.

    2013-12-01

    Although Global Climate Models (GCM) outputs should not be used directly to predict precipitation variability and change at the local scale, GCM projections of large-scale features in ocean and atmosphere can be applied to infer future statistical properties of climate at finer resolutions through empirical statistical downscaling techniques. A number of such downscaling methods have been proposed in the literature, and although all of them have advantages and limitations depending on the specific downscaling problem, most of them have been developed and tested in developed countries. In this research, we explore the use of statistical downscaling to generate future local precipitation scenarios in different locations in Northern Africa, where available data is sparse and missing values are frequently observed in the historical records. The presence of arid and semiarid regions in North African countries and the persistence of long periods with no rain pose challenges to the downscaling exercise since normality assumptions may be a serious limitation in the application of traditional linear regression methods. In our work, the development of monthly statistical relationships between the local precipitation and the large-scale predictors considers common Empirical Orthogonal Functions (EOFs) from different NCAR/Reanalysis climate fields (e.g., Sea Level Pressure (SLP) and Global Precipitation). GCM/CMIP5 data is considered in the predictor data set to analyze the future local precipitation. Both parametric (e.g., Generalized Linear Models (GLM)) and nonparametric (e,g,, Bootstrapping) approaches are considered in the regression analysis, and different spatial windows in the predictor fields are tested in the prediction experiments. In the latter, seasonal spatial cross-covariance between predictant and predictors is estimated by means of a teleconnections algorithm which was implemented to define the regions in the predictor domain that better captures the

  5. Oil and gas developments in North Africa in 1985

    SciTech Connect

    Michel, R.C.

    1986-10-01

    Petroleum rights in the 6 North African countries (Algeria, Egypt, Libya, Morocco, Sudan, and Tunisia) covered in this paper were 1,839,817 km/sup 2/ at the end of 1985, a decrease of 3% from the 1,896,446 km/sup 2/ held at the end of 1984. This decrease mainly is due to significant relinquishments made in Algeria, Egypt, and Tunisia. Morocco, however, had an increase of 18,087 km/sup 2/. Oil discoveries were reported in Algeria (possibly 5), Libya (at least 2), and Egypt (16). Only 1 gas find was made (in Morocco). According to sparse information, development drilling may have decreased markedly during 1985. Oil and condensate production increased by 3.1% to approximately 3,054,000 b/d compared to about 2,963,400 b/d in 1984. No statistics are currently available on gas production in North Africa. 8 figures, 27 tables.

  6. A Comprehensive Review of the Status of Early Childhood Development in the Middle East and North Africa.

    ERIC Educational Resources Information Center

    Khattab, Mohammad Salih

    This report reviews the status of early childhood education (ECE) programs in UNICEF's Middle East and North Africa region. The report compiles information about ECE programs in 18 countries based on a questionnaire sent to UNICEF country offices and other sources. The introduction sets out the economic and social rationales for investing in early…

  7. Girls' Drop-Out from Primary Schooling in the Middle East and North Africa: Challenges and Alternatives.

    ERIC Educational Resources Information Center

    Mehrah, Golnar

    The present situation in the Middle East and North Africa Region (MENA) regarding primary school drop-out and repetition, with special reference to the situation of the girl child, is examined in this study. The in-school as well as out-of-school causes of primary school drop-out are examined, and solutions that help reduce or eliminate the…

  8. HIV Surveillance and Epidemic Profile in the Middle East and North Africa

    PubMed Central

    Shawky, Sherine; Soliman, Cherif; Kassak, Kassem M.; Oraby, Doaa; El-Khoury, Danielle; Kabore, Inoussa

    2011-01-01

    Summary HIV infection is the most devastating infection that has emerged in the recent history. The risk of being infected can be associated with both individual’s knowledge and behavior and community vulnerability influenced by cultural norms, laws, politics, and social practices. Despite that the countries in the Middle East and North Africa have succeeded in keeping low the HIV epidemic rates, the number of identified infected cases are increasing. Since the appearance of the first AIDS cases, all the national authorities devoted their efforts to abort the epidemic in its early stages. The rate of new HIV infections across the Middle East and North Africa region are not at an alarming level, but the need for a concerted effort from nation-states and nongovernmental organizations to stem the spread of the virus across the region is vital. Most countries of the region have put in place better information systems to track the HIV epidemic, yet the passive HIV/AIDS reporting remains the cornerstone in the HIV surveillance systems. Several countries still believe that their current strategies are optimal to the HIV status within their territories and that their national strategies are appropriate to their low epidemic status that is not expected to grow. Additionally, these countries fear that establishing an HIV national program to survey risk behaviors may be perceived as an approval of these behaviors that are culturally and religiously unacceptable. This background article aims to summarize the HIV surveillance strategies and epidemic profile in 17 Arab countries in the Middle East and North Africa. The article, also, displays the national surveillance system and the epidemic profile in Egypt and Lebanon as models for the region. This information aims to provide useful insights that may help the national authorities in finding out the best surveillance strategies that allow merging and collecting biological and risk data which is an integral part of their

  9. Dust aerosol and optical properties over North Africa simulated with the ALADIN numerical prediction model from 2006 to 2010

    NASA Astrophysics Data System (ADS)

    Mokhtari, M.; Tulet, P.; Fischer, C.; Bouteloup, Y.; Bouyssel, F.; Brachemi, O.

    2015-02-01

    The seasonal cycle and optical properties of mineral dust aerosols in North Africa were simulated for the period from 2006 to 2010 using the numerical atmospheric model ALADIN coupled to the surface scheme SURFEX. The particularity of the simulations is that the major physical processes responsible for dust emission and transport, as well as radiative effects, are taken into account at short timescales and mesoscale resolution. The aim of these simulations is to quantify the dust emission and deposition, locate the major areas of dust emission and establish a climatology of aerosol optical properties in North Africa. The mean monthly Aerosol Optical Thickness (AOT) simulated by ALADIN is compared with the AOTs derived from the standard Dark Target (DT) and Deep Blue (DB) algorithms of the Aqua-MODIS (MODerate resolution Imaging Spectroradiometer) products over North Africa, and with a set of sun photometer measurements located at Banizoumbou, Cinzana, Soroa, Mbour and Capo Verde. The vertical distribution of dust aerosol represented by extinction profiles is also analysed using CALIOP (Cloud-Aerosol Lidar with Orthogonal Polarization) observations. The annual dust emission simulated by ALADIN over North Africa is 878 Tg year-1. The Bodélé depression appears to be the main area of dust emission in North Africa, with an average estimate of about 21.6 Tg year-1. The simulated AOTs are in good agreement with satellite and sun photometer observations. The positions of the maxima of the modelled AOTs over North Africa match the observed positions, and the ALADIN simulations satisfactorily reproduce the various dust events over the 2006-2010 period. The AOT climatology proposed in this paper provides a solid database of optical properties and consolidates the existing climatology over this region derived from satellites, the AERONET network and Regional Climate Models. Moreover, the three-dimensional distribution of the simulated AOTs also provides information about the

  10. Middle East, North Africa and Western Eurasia Seismic Research Database

    SciTech Connect

    O'Boyle, J L; Ruppert, S D; Hauk, T F; Dodge, D A; Ganzberger, M D; Ryall, F

    2003-07-14

    The National Nuclear Security Administration (NNSA) Ground-Based Nuclear Explosion Monitoring Research and Engineering (GNEM R&E) Program at Lawrence Livermore National Laboratory (LLNL) has made significant progress populating a comprehensive Seismic Research Database (SRDB) used for deriving seismic calibration parameters for the Middle East, North Africa and Western Eurasia (ME/NA/WE) regions. In addition to an overview of select individual information products, we present an overview of our visualization, integration, validation, and organizational processes. Development of these processes and the LLNL SRDB was necessitated by both the very large amount of data and information involved (over 15 terabytes) and the varied data and research result formats utilized. The LLNL SRDB allows for the collection of raw and contextual seismic data used in research, provides an interface for researchers to access data, provides a framework to store research results and integrate datasets, and supports assembly, integration and dissemination of datasets to the NNSA Knowledge Base (KB). The LLNL SRDB is a flexible and extensible framework consisting of a relational database (RDB), Geographical Information System (GIS), and associated product/data visualization and data management tools. This framework is designed to accommodate large volumes of data in diverse formats from many sources (both in-house-derived research and integrated contractor products), in addition to maintaining detailed quality control and metadata. In order to efficiently organize information within the LLNL SRDB, it was necessary to automate procedures needed to create and update database tables, but a large effort is still required by technicians and scientists to load special datasets, review results of automated processing and resolve quality issues. The LLNL SRDB currently has 3 million reconciled event origins and arrivals from several global, regional and local seismic bulletins and 30 million

  11. Mineralogical maturity in dunefields of North America, Africa and Australia

    USGS Publications Warehouse

    Muhs, D.R.

    2004-01-01

    Studies of dunefields in central and western North America show that mineralogical maturity can provide new insights into the origin and evolution of aeolian sand bodies. Many of the world's great sand seas in Africa, Asia and Australia are quartz-dominated and thus can be considered to be mineralogically mature. The Algodones (California) and Parker (Arizona) dunes in the southwestern United States are also mature, but have inherited a high degree of mineralogical maturity from quartz-rich sedimentary rocks drained by the Colorado River. In Libya, sediments of the Zallaf sand sea, which are almost pure quartz, may have originated in a similar fashion. The Fort Morgan (Colorado) and Casper (Wyoming) dunefields in the central Great Plains of North America, and the Namib sand sea of southern Africa have an intermediate degree of mineralogical maturity because their sources are large rivers that drained both unweathered plutonic and metamorphic rocks and mature sedimentary rocks. Mojave Desert dunefields in the southwestern United States are quite immature because they are in basins adjacent to plutonic rocks that were their sources. Other dunefields in the Great Plains of North America (those in Nebraska and Texas) are more mature than any possible source sediments and therefore reflect mineralogical evolution over time. Such changes in composition can occur because of either of two opposing long-term states of the dunefield. In one state, dunes are stable for long periods of time and chemical weathering depletes feldspars and other weatherable minerals in the sediment body. In the other state, which is most likely for the Great Plains, abrasion and ballistic impacts deplete the carbonate minerals and feldspars because the dunes are active for longer periods than they are stable. ?? 2003 Elsevier B.V. All rights reserved.

  12. Two-station phase velocity determination for structure in North Africa

    SciTech Connect

    Hazler, S; Pasyanos, M; Sheehan, A; Walter, W

    1999-07-28

    The seismic structure of North Africa is poorly understood due to the relative paucity of stations and seismicity when compared to other continental regions of the world. A better understanding of the velocity structure in this area will allow improved models of travel times and regional phase amplitudes. Such models will improve location and identification capability in this region leading to more effective monitoring of the Comprehensive Nuclear-Test-Ban Treaty. Using regional-to-teleseismic Rayleigh and Love waves that traverse the area we can obtain information about the region's seismic structure by examining phase velocity as a function of period. We utilize earthquakes from the tectonically active regions bounding North Africa (Mediterranean, Red Sea, East African Rift, and Mid-Atlantic Ridge) recorded at broadband seismic stations distributed throughout the region. A two-station method is utilized to determine phase velocity information along the interstation segment of the ray path. The two-station method provides particular advantage in this region as it dramatically increases the number of events available to provide pure North African sampling. Bandpass filters are applied to the seismograms so that peaks and troughs may be correlated. The phase is unwrapped and a difference curve computed. The difference curve is then converted to a phase velocity dispersion curve. Phase velocity curves are constructed in the range of 10 to 120 seconds. Rayleigh and Love waves in this period range are most sensitive to the shear velocity structure of the lithosphere and can be used in combination with additional independent seismic observations (e.g. Pn tomography, surface wave group velocity tomography, receiver functions, etc.) to construct reliable velocity models. We compare velocities computed in this study to those generated from well known models for similar tectonic regions throughout the world in order to better define the tectonic setting of North Africa

  13. Crust and Upper Mantle of North Africa Using Libyan Seismic Data

    NASA Astrophysics Data System (ADS)

    Pasyanos, M. E.; Eshwehdi, A.

    2005-12-01

    We investigate the crust and upper mantle structure of North Africa using Libyan seismic data. Libya sits at the transition between the relatively aseismic continental crust of the African plate and the seismically active oceanic crust under the Mediterranean Sea which is subducting under the Eurasian Plate along the Calabrian, Hellenic, and Cyprean Arcs. The country also encompasses the Sirte Basin to the north and the smaller Murzuk and Kufra basins in the south. Broadband data from several seismic stations in Libya provide an opportunity for studying the velocity structure of the region. We have made some preliminary dispersion measurements from these stations and have found notable improvements in the group velocity tomography model by incorporating the additional measurements. We will be adding to this analysis by making dispersion measurements from regional events and receiver functions for teleseismic events. Recently, we have been employing methods to jointly invert both surface wave dispersion data and teleseismic receiver functions. The technique holds great promise in accurately estimating seismic structure, including important tectonic parameters such as basin thickness, crustal thickness, upper mantle velocity, as well as more detail about the upper mantle (lithospheric thickness and presence of anisotropy). We propose to apply this method to data from several Libyan stations where we can and, in the absence of receiver functions, invert the dispersion data only. The technique holds the promise of improving our understanding of the crust and upper mantle in Libya and how it fits into the larger tectonic picture of North Africa.

  14. NORTH AMERICAN REGIONAL ACTION PLAN ON MERCURY

    EPA Science Inventory

    The North American Regional Action Plan (NARAP) on Mercury is one of a number of action plans that stem from the North American Agreement on Environmental Cooperation between the governments of Canada, Mexico and the United States. That Agreement established the Commission for En...

  15. Potential source regions of dust accumulated in northern Africa

    NASA Astrophysics Data System (ADS)

    Wasowska, S.; Woronko, B.

    2012-04-01

    Iguidi and Chech-Adrar, although the most probable source area is Erg Occidental. Tunisian dusts come from vast expanses of Erg Oriental and Chott-el-Jerid. The potential source of the dusts accumulated in Alexandria could be Libyan Desert. This does not preclude also much more distant sources of sediment, as for instance ergs from North Sudan. From the other hand the presence of shell parts of diatoms of the Actinoptychus genus may indicate the dispelling of the Nile alluvium. Key words: source region, aeolian accumulation, north Africa, textural features of grains, aeolian dust, meteorological situation, Sahara, SEM analysis

  16. Pre-Islamic Religious Monuments in North Africa

    NASA Astrophysics Data System (ADS)

    Esteban, César

    I review data on the orientations of pre-Islamic religious monuments in North Africa dating from the 5th century BC to the 7th century AD and covering most of the present-day Maghreb, from Western Libya to Morocco. A sample of more than 100 Roman temples shows a rather random orientation pattern except for those dedicated to Saturn, which follow a clear relation to the rising sun or moon. This group of temples were built over previous sanctuaries dedicated to the Punic god Baal Hammon. In fact, a sample of genuine Punic sanctuaries presents a similar orientation pattern. I also discuss evidence of remarkable astronomical markers found in several of the temples. Christian churches of this area, among the earliest ones erected in the Mediterranean, also show a clear lunisolar orientation pattern.

  17. Additional evidence on the use of personal ornaments in the Middle Paleolithic of North Africa

    PubMed Central

    d'Errico, Francesco; Vanhaeren, Marian; Barton, Nick; Bouzouggar, Abdeljalil; Mienis, Henk; Richter, Daniel; Hublin, Jean-Jacques; McPherron, Shannon P.; Lozouet, Pierre

    2009-01-01

    Recent investigations into the origins of symbolism indicate that personal ornaments in the form of perforated marine shell beads were used in the Near East, North Africa, and SubSaharan Africa at least 35 ka earlier than any personal ornaments in Europe. Together with instances of pigment use, engravings, and formal bone tools, personal ornaments are used to support an early emergence of behavioral modernity in Africa, associated with the origin of our species and significantly predating the timing for its dispersal out of Africa. Criticisms have been leveled at the low numbers of recovered shells, the lack of secure dating evidence, and the fact that documented examples were not deliberately shaped. In this paper, we report on 25 additional shell beads from four Moroccan Middle Paleolithic sites. We review their stratigraphic and chronological contexts and address the issue of these shells having been deliberately modified and used. We detail the results of comparative analyses of modern, fossil, and archaeological assemblages and microscopic examinations of the Moroccan material. We conclude that Nassarius shells were consistently used for personal ornamentation in this region at the end of the last interglacial. Absence of ornaments at Middle Paleolithic sites postdating Marine Isotope Stage 5 raises the question of the possible role of climatic changes in the disappearance of this hallmark of symbolic behavior before its reinvention 40 ka ago. Our results suggest that further inquiry is necessary into the mechanisms of cultural transmission within early Homo sapiens populations. PMID:19717433

  18. Linking Climate to Incidence of Zoonotic Cutaneous Leishmaniasis (L. major) in Pre-Saharan North Africa

    NASA Technical Reports Server (NTRS)

    Bounoua, Lahouari; Kahime, Kholoud; Houti, Leila; Blakey, Tara; Ebi, Kristie L.; Zhang, Ping; Imhoff, Marc L.; Thome, Kurtis J.; Dudek, Claire; Sahabi, Salah A.; Messouli, Mohammed; Makhlouf, Baghdad; Laamrani, Abderrahmane El.; Boumezzough, Ali

    2013-01-01

    Shifts in surface climate may have changed the dynamic of zoonotic cutaneous leishmaniasis (ZCL) in the pre-Saharan zones of North Africa. Caused by Leishmania major, this form multiplies in the body of rodents serving as reservoirs of the disease. The parasite is then transmitted to human hosts by the bite of a Phlebotomine sand fly (Diptera: Psychodidae) that was previously fed by biting an infected reservoir. We examine the seasonal and interannual dynamics of the incidence of this ZCL as a function of surface climate indicators in two regions covering a large area of the semi-arid Pre-Saharan North Africa. Results suggest that in this area, changes in climate may have initiated a trophic cascade that resulted in an increase in ZCL incidence. We find the correlation between the rainy season precipitation and the same year Normalized Difference Vegetation Index (NDVI) to be strong for both regions while the number of cases of ZCL incidence lags the precipitation and NDVI by 2 years. The zoonotic cutaneous leishmaniasis seasonal dynamic appears to be controlled by minimum temperatures and presents a 2-month lag between the reported infection date and the presumed date when the infection actually occurred. The decadal increase in the number of ZCL occurrence in the region suggests that changes in climate increased minimum temperatures sufficiently and created conditions suitable for endemicity that did not previously exist. We also find that temperatures above a critical range suppress ZCL incidence by limiting the vector's reproductive activity.

  19. Linking Climate to Incidence of Zoonotic Cutaneous Leishmaniasis (L. major) in Pre-Saharan North Africa

    PubMed Central

    Bounoua, Lahouari; Kahime, Kholoud; Houti, Leila; Blakey, Tara; Ebi, Kristie L.; Zhang, Ping; Imhoff, Marc L.; Thome, Kurtis J.; Dudek, Claire; Sahabi, Salah A.; Messouli, Mohammed; Makhlouf, Baghdad; Laamrani, Abderahmane El.; Boumezzough, Ali

    2013-01-01

    Shifts in surface climate may have changed the dynamic of zoonotic cutaneous leishmaniasis (ZCL) in the pre-Saharan zones of North Africa. Caused by Leishmania major, this form multiplies in the body of rodents serving as reservoirs of the disease. The parasite is then transmitted to human hosts by the bite of a Phlebotomine sand fly (Diptera: Psychodidae) that was previously fed by biting an infected reservoir. We examine the seasonal and interannual dynamics of the incidence of this ZCL as a function of surface climate indicators in two regions covering a large area of the semi-arid Pre-Saharan North Africa. Results suggest that in this area, changes in climate may have initiated a trophic cascade that resulted in an increase in ZCL incidence. We find the correlation between the rainy season precipitation and the same year Normalized Difference Vegetation Index (NDVI) to be strong for both regions while the number of cases of ZCL incidence lags the precipitation and NDVI by 2 years. The zoonotic cutaneous leishmaniasis seasonal dynamic appears to be controlled by minimum temperatures and presents a 2-month lag between the reported infection date and the presumed date when the infection actually occurred. The decadal increase in the number of ZCL occurrence in the region suggests that changes in climate increased minimum temperatures sufficiently and created conditions suitable for endemicity that did not previously exist. We also find that temperatures above a critical range suppress ZCL incidence by limiting the vector’s reproductive activity. PMID:23912199

  20. Oil and gas developments in North Africa in 1984

    SciTech Connect

    Michel, R.Ch.

    1985-10-01

    Petroleum rights in the 6 North African countries (Algeria, Egypt, Libya, Morocco, Sudan, and Tunisia) covered in this paper were 1,906,065 km/sup 2/ at the end of 1984, an increase of 4.6% from the 1,821,966 km/sup 2/ in force at the end of 1983. This increase is due to large awards in the Sudan despite significant relinquishments elsewhere. Seismic surveys conducted during 1984 decreased to about 510.5 crew-months onshore and 29.5 crew-months offshore. However, exploration in and off Egypt was higher compared to 1983. Exploratory drilling was lower, with only 125 wells drilled compared to 179 tests completed in 1983. The main decrease was in Egypt and Sudan, but drilling in Libya resulted in 20 more completions. A significant oil discovery was made in the offshore part of the Sirte basin, off southwest Cyrenaica. The success rate in North Africa ranged from 19% to 50% (Libya). Development drilling increased during 1984, as higher activity appears to have taken place in 3 countries. Oil production, with an estimated daily rate of 2,952,570 bbl, was up 2.8% from 1983 (2,871,460 BOPD). In Egypt, 7 fields located in the Gulf of Suez area went on stream during the year. Political unrest, which prevailed in southern Sudan during most of 1984, will likely delay the start-up of production in several fields. No statistics are available on gas production in North African countries.

  1. Africa Section. Regional Activities Division. Papers.

    ERIC Educational Resources Information Center

    International Federation of Library Associations, The Hague (Netherlands).

    Papers on the role and services of African libraries and the education of African librarians, which were presented at the 1983 International Federation of Library Associations (IFLA) conference, include: (1) "The Information Sector in the Economic Development of Africa: The Potential Role for Libraries," in which Benzies Y. Boadi (Nigeria)…

  2. Integrated depositional model for the Cenomanian Turonian organic-rich strata in North Africa

    NASA Astrophysics Data System (ADS)

    Lüning, S.; Kolonic, S.; Belhadj, E. M.; Belhadj, Z.; Cota, L.; Barić, G.; Wagner, T.

    2004-01-01

    During the Late Cenomanian-Early Turonian (C/T) Oceanic Anoxic Event (OAE2), organic-rich strata was deposited in rift shelf basins and slopes across North Africa and in deep-sea basins of the adjacent oceans. Based on a review of published and unpublished information, this paper documents the distribution and organic-richness of C/T strata across the whole region within a palaeogeographic framework and systematically analyses the conditions and processes, which controlled their deposition. Previously, the C/T in North Africa has been most intensively studied in southern Morocco (Tarfaya) and Tunisia. Only little data is availabe for other parts of North Africa, namely Algeria, Libya and Egypt, because distribution of C/T Corg strata there becomes more patchy. A general decrease in peak organic richness and black shale thickness occurs from west to east, partly as a result of upwelling along the Moroccan Atlantic coast and the absence of upwelling in the eastern Mediterranean area. Furthermore, in the confined central Atlantic, the oxygen minimum zone (OMZ) in many places reached down to the deep-sea floor (3-4 km), while the lower limit of the OMZ along the North African Tethys was much shallower and underlain by oxic water masses. As documented by high resolution biostratigraphic and chemostratigraphic data, C/T black shale deposition in most areas outside the upwelling zone are restricted to a strong, eustatic, latest Cenomanian transgressive phase. Triggered by this sea-level rise, the OMZ impinged onto the North African continental shelf and the margins of intrashelf basins, which mostly formed during the Early Cretaceous as halfgrabens. Important units containing C/T organic-rich strata in the region are the Atlantic Tarfaya black shales (Morocco, Western Sahara), black shales and phtanites in the Moroccan and Algerian Atlas, the Bahloul Fm. in the SE Constantine Basin and in northern and central Tunisia, the Etel Fm. in the Sirte Basin, the Al Hilal Fm. in

  3. Archaeomagnetic and rock magnetic study of six kilns from North Africa (Tunisia and Morocco)

    NASA Astrophysics Data System (ADS)

    Gomez-Paccard, M.; McIntosh, G.; Beamud, E.; Chauvin, A.; Pavon-Carrasco, F. J.; Thiriot, J.

    2012-04-01

    New full-vector archaeomagnetic data for North Africa recovered from the study of six kilns, five from Tunisia and one from Morocco, are presented. Archaeological and historical considerations, along with three radiocarbon dates, indicate that the age of the kilns ranges between the 9th and 15th centuries AD. Rock magnetic analyses showed that the principal magnetic carriers are magnetite and low Ti titanomagnetite, along with variable contributions of thermally stable maghemite and a high coercivity phase with low unblocking temperatures. The magnetic mineralogy of the studied material is thermally stable and behaves ideally during archaeointensity experiments. Stepwise alternating field demagnetisation isolated a single, stable, characteristic remanence component with very well defined directions at both specimen and structure levels. Mean archaeointensities have been obtained from successful classical Thellier experiments conducted on between five and eight independent samples per kiln. Thermoremanent magnetisation (TRM) anisotropy and cooling rate effects upon TRM intensity have been investigated. The results showed that these effects are low for four of the six studied kilns, with differences between the uncorrected and corrected means of less than 3%. For the other two structures differences between the uncorrected and corrected mean site intensities are 4.4% and 5.8%. These results highlight the necessity for TRM anisotropy and cooling rate corrections in archaeomagnetic studies if accurate archaeointensities are to be obtained. The new results suggest that high intensities occurred in Northwest Africa during the 9th century. Although more data are clearly needed in order to define this period of high intensity, the results are in agreement with the available European archaeointensity data. A comparison between the new data, other available archaeomagnetic determinations in nearby locations, and palaeosecular variation (PSV) curves derived from the regional

  4. Archaeomagnetic and rock magnetic study of six kilns from North Africa (Tunisia and Morocco)

    NASA Astrophysics Data System (ADS)

    Gómez-Paccard, Miriam; McIntosh, Gregg; Chauvin, Annick; Beamud, Elisabet; Pavón-Carrasco, Francisco J.; Thiriot, Jacques

    2012-04-01

    from the regional SCHA.DIF.3k and global ARCH3K.1 geomagnetic field models shows good agreement between the new data and directional results derived from the models. However, some differences are observed between geomagnetic field models intensity results and available archaeointensity data for the studied regions. This highlights the need for new data for unexplored regions such as North Africa. The new data presented here better constrains the evolution of the geomagnetic field during historical times in this region. They represent a new step towards the construction of a reference PSV curve for Northwest Africa. Once established, this curve will represent a new dating method for this region.

  5. Abrupt post-glacial climate events in West Asia and North Africa monsoon domains

    NASA Astrophysics Data System (ADS)

    Gasse, Françoise; Van Campo, Elise

    1994-09-01

    Regions beyond the present or past penetration of the Indian and African monsoons have experienced several large and abrupt climatic fluctuations over the past 13 14C kyr. Pollen and lake records from West Asia (Western Tibet and Rajasthan), East Africa (Ethiopia) and West Africa (Western Sahara, Sahel and subequatorial Africa) were selected on the basis of chronological control, sensitivity of both site and environmental indicators to climate change, the continuity of the record, and interdisciplinary control of the palaeoclimatic interpretation. Conditions wetter than those of today prevailed during the early-mid-Holocene period, but major dry spells are recorded at all sites during the intervals ˜ 11.0-9.5 kyr BP, ˜ 8-7 kyr BP and 3-4 kyr BP. Several records also suggest dry events of minor amplitude around 6 kyr BP. Potential boundary forcings of insolation and sea surface and tropical land surface conditions are discussed. The solar radiation accounts for the general envelop of the post-glacial monsoon fluctuations, but explains neither the timing nor the amplitude of the short-term changes. In spite of apparent covariation between fluctuations in sea surface conditions in the North Atlantic and the monsoon record, no direct mechanism could be found relating the intensity of the oceanic thermohaline conveyor belt to the monsoon strength. Changes in tropical land surface conditions (soil moisture negative feedback, and changes in CH 4 production from wetlands) provide a more satisfactory hypothesis for explaining abrupt reversal events.

  6. Ancient glaciations and hydrocarbon accumulations in North Africa and the Middle East

    NASA Astrophysics Data System (ADS)

    Le Heron, Daniel Paul; Craig, Jonathan; Etienne, James L.

    2009-04-01

    At least six glaciations are purported to have affected North Africa and the Middle East region over the last one billion years, including two in the Cryogenian (Neoproterozoic), Hirnantian (Late Ordovician), Silurian, Carboniferous and Early Permian events. The sedimentary record associated with these glaciations, together with the intensity to which each has been investigated, is highly variable. As hydrocarbon exploration proceeds aggressively across the North Africa and Middle East regions, we review the relationship between glaciation and hydrocarbon accumulations. With the exception of Oman, and locally Egypt, which were tectonically active both during the Neoproterozoic and Early Palaeozoic all glaciations took place along an essentially stable passive continental margin. During the Neoproterozoic, two glaciations are recognised, referred to as older and younger Cryogenian glaciations respectively. Both of these Cryogenian events are preserved in Oman; only the younger Cryogenian has been reported in North Africa in Mauritania and Mali at the flanks of the Taoudenni Basin. The process of initial deglaciation in younger Cryogenian glaciations resulted in incision, at least locally producing large-bedrock palaeovalleys in Oman, and the deposition of glacial diamictites, gravels, sandstones and mudstones. As deglaciation progressed "cap carbonates" were deposited, passing vertically into shale with evidence for deposition in an anoxic environment. Hence, younger Cryogenian deglaciation may be associated with hydrocarbon source rock deposits. Hirnantian (Late Ordovician) glaciation was short lived (< 0.5 Myr) and affected intracratonic basins of Mauritania, Morocco, Algeria, Libya, Egypt and Saudi Arabia. The organisation of the glacial sedimentary record is considered to be controlled at the basin-scale by the location of fast-flowing ice streams active during glacial maxima, and by the processes of meltwater release during glacial recession. In these latter

  7. Identifying Dust Sources in North Africa and Modeling Patterns of Dust Emissions From These Sources

    NASA Astrophysics Data System (ADS)

    Ballantine, J. A.; Okin, G. S.; Roberts, D. A.

    2003-12-01

    Atmospheric models are requiring more accurate representations of the surface in modeling emissions of dust from the surface and the nutrients attached to fine mineral particles. Regional to continental scale characterization of surface landforms that are susceptible to erosion has become possible with the advent of satellites that monitor the land surface at moderate spectral and spatial resolution (e.g. MODIS). The most productive dust sources in the world are in the Sahara Desert and the Sahel, in areas where human pressures may be making the landscape more susceptible to wind erosion. This project seeks to model dust emissions in the Sahara and Sahel with estimates of surface parameters from satellite imagery and ancillary data. A map of landforms for Africa, north of 10 degrees, was constructed using a multiple endmember spectral mixture analysis (MESMA) of the MODIS 500 meter, 7 band, reflectance product. The magnitude of surface winds acting on the landforms was determined from forecast models. Surface parameters (vegetation characteristics, threshold wind velocity, and grain size distribution) were estimated for the imagery. Estimates of nutrient concentration on Saharan/Sahelian dust were used to estimate nutrient emissions. The results highlight patterns of dust emission from sources in North Africa and are compared with modeled and observed sources in the literature.

  8. Strategy for managing water in the Middle East and North Africa. Arabic edition

    SciTech Connect

    Berkoff, J.

    1995-03-21

    Proposes a practical, step-by-step approach to managing water resources in a coordinated and sustainable manner. The people of the Middle East and North Africa have faced scarce water resources since time immemorial. Today, burgeoning populations dwarf the concerns of the past. New strategies for planning and managing water are urgently needed to avoid escalating conflicts and to reverse environmental degradation. This booklet details the implications of a new World Bank policy for the region, calling for a strong effort by governments and Bank staff to manage water resources in a coordinated and sustainable manner. A practical, step-by-step strategy is proposed that could lead to new Bank-funded operations throughout the water sector. The issues involved are complex but must be addressed if water scarcity is not to hinder development projects. The strategy proposed in this booklet could help build a new partnership for sustainable water management between the World Bank and regional governments.

  9. Mortality in Patients with HIV-1 Infection Starting Antiretroviral Therapy in South Africa, Europe, or North America: A Collaborative Analysis of Prospective Studies

    PubMed Central

    Boulle, Andrew; Schomaker, Michael; May, Margaret T.; Hogg, Robert S.; Shepherd, Bryan E.; Monge, Susana; Keiser, Olivia; Lampe, Fiona C.; Giddy, Janet; Ndirangu, James; Garone, Daniela; Fox, Matthew; Ingle, Suzanne M.; Reiss, Peter; Dabis, Francois; Costagliola, Dominique; Castagna, Antonella; Ehren, Kathrin; Campbell, Colin; Gill, M. John; Saag, Michael; Justice, Amy C.; Guest, Jodie; Crane, Heidi M.; Egger, Matthias; Sterne, Jonathan A. C.

    2014-01-01

    Background High early mortality in patients with HIV-1 starting antiretroviral therapy (ART) in sub-Saharan Africa, compared to Europe and North America, is well documented. Longer-term comparisons between settings have been limited by poor ascertainment of mortality in high burden African settings. This study aimed to compare mortality up to four years on ART between South Africa, Europe, and North America. Methods and Findings Data from four South African cohorts in which patients lost to follow-up (LTF) could be linked to the national population register to determine vital status were combined with data from Europe and North America. Cumulative mortality, crude and adjusted (for characteristics at ART initiation) mortality rate ratios (relative to South Africa), and predicted mortality rates were described by region at 0–3, 3–6, 6–12, 12–24, and 24–48 months on ART for the period 2001–2010. Of the adults included (30,467 [South Africa], 29,727 [Europe], and 7,160 [North America]), 20,306 (67%), 9,961 (34%), and 824 (12%) were women. Patients began treatment with markedly more advanced disease in South Africa (median CD4 count 102, 213, and 172 cells/µl in South Africa, Europe, and North America, respectively). High early mortality after starting ART in South Africa occurred mainly in patients starting ART with CD4 count <50 cells/µl. Cumulative mortality at 4 years was 16.6%, 4.7%, and 15.3% in South Africa, Europe, and North America, respectively. Mortality was initially much lower in Europe and North America than South Africa, but the differences were reduced or reversed (North America) at longer durations on ART (adjusted rate ratios 0.46, 95% CI 0.37–0.58, and 1.62, 95% CI 1.27–2.05 between 24 and 48 months on ART comparing Europe and North America to South Africa). While bias due to under-ascertainment of mortality was minimised through death registry linkage, residual bias could still be present due to differing approaches to and

  10. Oil and gas developments in North Africa in 1982

    SciTech Connect

    Nicod, M.A.

    1983-10-01

    Within the 2,044,851 km/sup 2/ area described in this paper, petroleum rights in force at the end of 1982 in the 6 countries (Algeria, Egypt, Libya, Morocco, Sudan, Tunisia) remained at about the same level (up 1%) as at the end of 1981. A large award in Sudan made up for a decrease in leased areas in other countries. Both onshore and offshore seismic activity decreased during 1982 in all countries described, except in Sudan, where a significant effort is continuing. Exploration drilling activity also decreased with 166 wells and 330,500 m drilled, compared with 169 wells and 473,000 m drilled in 1981. The success rate was about 36%, compared with 40% in 1981. No new petroleum provinces were discovered. Offshore exploratory drilling was less successful in 1982 (15 discoveries) than in 1981 (24 discoveries). In Sudan, Chevron continued to find oil with 6 discoveries, the most significant being the Heglig field. In Morocco, the Societe Cherifienne des Petroles resumed exploration after a long period of inactivity. Development drilling activity remained the same in most countries, except in Tunisia, where 13 development wells were drilled in 1982 compared with 3 in 1981. Oil production in North Africa decreased 1.4% during 1982, with an average of 2,610,500 BOPD compared with 2,648,500 in 1981. A new offshore field (Shell's Tazerka) was put on stream in Tunisia. This field is the deepest producing field in the Mediterranean (250 m (820 ft) water depth). Utilized natural gas production is estimated to about 2,000 MMCFGD.

  11. Teaching about Women and Islam in North Africa: Integrating Postcolonial Feminist Theory in the Classroom

    ERIC Educational Resources Information Center

    Zayzafoon, Lamia Ben Youssef

    2011-01-01

    Using postcolonial feminist theory, the researcher attempts in this article to redefine the interpretive framework through which courses on Islam and North African women are being taught in American undergraduate classes. Several conceptual limitations have been identified: inadequate knowledge of the geography and history of North Africa; the…

  12. Expansion of student activities in Africa: from south to north

    NASA Astrophysics Data System (ADS)

    Cherif, Rim; Ben Salem, Amine; Gueddana, Amor; Zghal, Mourad; Naidoo, Darryl; Forbes, Andrew; Heidt, Alexander M.; Rohwer, Erich G.

    2014-07-01

    Optics and photonics research in Africa has gradually grown in the past ten years with a very active optical community involved in state-of-the-art research. Despite relatively low resources, optics research in the continent is competitive with many international benchmarks and has had a significant impact within the African continent. In the past five years, a group of dynamic students have developed the student chapter network from Tunisia to South Africa. The first student chapters of the optical society of America (OSA) and the international society for optics and photonics (SPIE) were established in South Africa (in the Council for Scientific and Industrial Research (CSIR) and in the University of Stellenbosch), followed by a chapter in Tunisia (Engineering school of communications of Tunis, Sup'Com). In this paper, we will present the major activities of the student chapters of Tunisia and South Africa, and how they are promoting optics and photonics in Africa.

  13. Genomic Ancestry of North Africans Supports Back-to-Africa Migrations

    PubMed Central

    Gravel, Simon; Wang, Wei; Brisbin, Abra; Byrnes, Jake K.; Fadhlaoui-Zid, Karima; Zalloua, Pierre A.; Moreno-Estrada, Andres; Bertranpetit, Jaume; Bustamante, Carlos D.; Comas, David

    2012-01-01

    North African populations are distinct from sub-Saharan Africans based on cultural, linguistic, and phenotypic attributes; however, the time and the extent of genetic divergence between populations north and south of the Sahara remain poorly understood. Here, we interrogate the multilayered history of North Africa by characterizing the effect of hypothesized migrations from the Near East, Europe, and sub-Saharan Africa on current genetic diversity. We present dense, genome-wide SNP genotyping array data (730,000 sites) from seven North African populations, spanning from Egypt to Morocco, and one Spanish population. We identify a gradient of likely autochthonous Maghrebi ancestry that increases from east to west across northern Africa; this ancestry is likely derived from “back-to-Africa” gene flow more than 12,000 years ago (ya), prior to the Holocene. The indigenous North African ancestry is more frequent in populations with historical Berber ethnicity. In most North African populations we also see substantial shared ancestry with the Near East, and to a lesser extent sub-Saharan Africa and Europe. To estimate the time of migration from sub-Saharan populations into North Africa, we implement a maximum likelihood dating method based on the distribution of migrant tracts. In order to first identify migrant tracts, we assign local ancestry to haplotypes using a novel, principal component-based analysis of three ancestral populations. We estimate that a migration of western African origin into Morocco began about 40 generations ago (approximately 1,200 ya); a migration of individuals with Nilotic ancestry into Egypt occurred about 25 generations ago (approximately 750 ya). Our genomic data reveal an extraordinarily complex history of migrations, involving at least five ancestral populations, into North Africa. PMID:22253600

  14. Accuracy of teleseismic event locations in the Middle East and North Africa

    SciTech Connect

    Sweeney, J.J.

    1996-12-04

    Seismic characterization at the regional level requires accurate determination of phases and travel times for many combinations of stations and events. An important consideration in the process is the accuracy of event locations. The LLNL Comprehensive Test Ban Treaty Research Program is currently working on data from the Middle East and North Africa, where seismic station coverage is relatively sparse and ``ground truth`` seismic source information is practically nonexistent. In this report the investigator use after shock studies as a source of local ground truth. He evaluates teleseismic location accuracy by comparing hypocenters determined by local networks with those determined teleseismically [e.g. the International Seismological Center (ISC) and the National Earthquake Information Center (NEIC)]. Epicentral locations, origin times, and depth determinations of events from three aftershocks studies (Algeria, Armenia, and Iran) and one local network study (Iran) are compared with ISC and NEIC locations for the same events. The key parameter for the ISC locations is the number of observations used in the location determination. For more than 40-50 observations, the agreement rapidly diminishes and ISC locations can differ from local determinations by as much as 80 km or more. Events in Iran show a distinct bias of ISC location errors toward the northeast; events in Armenia and Algeria show no directional bias. This study shows that only events with ISC M{sub b} {gt} 4.4-4.5 or NEIS M{sub b} {gt} 4.7-4. should be used for compiling travel time information from teleseismic bulletins in the Middle East/North Africa region when locations from the NEIC and ISC bulletins are used.

  15. Overview of cervical cancer screening practices in the extended Middle East and North Africa countries.

    PubMed

    Sancho-Garnier, Hélène; Khazraji, Youssef Chami; Cherif, Moktar Hamdi; Mahnane, Abbes; Hsairi, Mohamed; El Shalakamy, Amr; Osgul, Nejat; Tuncer, Murat; Jumaan, Aisha O; Seoud, Muhieddine

    2013-12-30

    National Organized Cervical Cancer Screening (NOCCS) programs are lacking in most of the "Extended Middle East and North Africa" (EMENA) countries. Consequently, most cervical cancers are diagnosed late and are associated with high mortality. In fact, in most of these countries, national mortality data are unknown due to the absence of population-based mortality registries. Most countries of the EMENA practice more or less limited opportunistic, cytology-based, screening tests, which often lack quality assurance and follow-up care. A few countries, within the initiation of a National Cancer Control Plan, have just started to implement organized screening programs using, for cervical cancer detection, visual inspection with acetic acid (Morocco) or cytology (Turkey). Moreover, most countries of the EMENA lack national guideline, as well as resources for the management of abnormal cytologic screening (or any other screening test). The main obstacle for the implementation of NOCCS is a lack of political understanding to support such public health programs and provide the necessary resources. Other obstacles that hinder the participation of women in cervical screening include a lack of knowledge of the disease, socio-religious and cultural barriers, and geographic and economic difficulties in accessing medical services. These countries are already convinced that prevention of cervical cancers in women who have cervical intraepithelial neoplasia is possible through various screening and treatment algorithms, but most countries still need to invest in well organized programs that can reduce cervical cancer incidence and mortality in women. This article forms part of a regional report entitled "Comprehensive Control of HPV Infections and Related Diseases in the Extended Middle East and North Africa Region" Vaccine Volume 31, Supplement 6, 2013. Updates of the progress in the field are presented in a separate monograph entitled "Comprehensive Control of HPV Infections and

  16. Dust forecast over North Africa: verification with satellite and ground based observations

    NASA Astrophysics Data System (ADS)

    Singh, Aditi; Kumar, Sumit; George, John P.

    2016-05-01

    Arid regions of North Africa are considered as one of the major dust source. Present study focuses on the forecast of aerosol optical depth (AOD) of dust over different regions of North Africa. NCMRWF Unified Model (NCUM) produces dust AOD forecasts at different wavelengths with lead time upto 240 hr, based on 00UTC initial conditions. Model forecast of dust AOD at 550 nm up to 72 hr forecast, based on different initial conditions are verified against satellite and ground based observations of total AOD during May-June 2014 with the assumption that except dust, presence of all other aerosols type are negligible. Location specific and geographical distribution of dust AOD forecast is verified against Aerosol Robotic Network (AERONET) station observations of total and coarse mode AOD. Moderate Resolution Imaging Spectroradiometer (MODIS) dark target and deep blue merged level 3 total aerosol optical depth (AOD) at 550 nm and Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) retrieved dust AOD at 532 nm are also used for verification. CALIOP dust AOD was obtained by vertical integration of aerosol extinction coefficient at 532 nm from the aerosol profile level 2 products. It is found that at all the selected AERONET stations, the trend in dust AODs is well predicted by NCUM up to three days advance. Good correlation, with consistently low bias (~ +/-0.06) and RMSE (~ 0.2) values, is found between model forecasts and point measurements of AERONET, except over one location Cinzana (Mali). Model forecast consistently overestimated the dust AOD compared to CALIOP dust AOD, with a bias of 0.25 and RMSE of 0.40.

  17. Infectious diseases in North Africa and North African immigrants to Europe.

    PubMed

    Khyatti, Meriem; Trimbitas, Roxana-Delia; Zouheir, Yassine; Benani, Abdelouaheb; El Messaoudi, Moulay-Driss; Hemminki, Kari

    2014-08-01

    The epidemiological transition has reduced infectious diseases mortality in most European countries, yet increased migrant influx risks importing diseases. All reported prevalence rates must be considered on a case-by-case basis depending on the disease in question, respective European Union (EU) country and migratory patterns at work. Tuberculosis has seen a re-emergence in Europe and is concentrated among migrants. Migrants arriving from North Africa (NA) and sub-Saharan Africa (SSA) carry higher rates of hepatitis C and B than the local EU population. The human immunodeficiency virus (HIV) impact of NA migrants to Europe is very low but a hallmark of the HIV epidemic is the penetration and circulation of non-B strains, recombinant forms and HIV-drug-resistant profiles through SSA migrants using NA as a transit point into Europe. Leishmaniasis is a re-emerging zoonotic disease prevalent to Southern Europe although not specifically isolated in migrant groups. Although not endemic in NA countries, malaria represent S: a risk in terms of re-emergence in Europe through transitory migrants arriving from SSA with the destination to Europe. Schistosomiasis has been largely eliminated from NA. High migrant flux into European countries has resulted in changing patterns of communicable disease and collectively requires a continuous surveillance. World Health Organization guidelines recommend targeted screening and preventative vaccination, followed by integration of migrants into the local health-care systems allowing for long-term treatment and follow-up. Finally, effective public health campaigns as a form of prevention are essential for the mitigation of disease dissemination in the migrant pool and for second-generation children of migrants. PMID:25107998

  18. Evaluation ofthe Middle East and North Africa Land Data Assimilation System

    NASA Technical Reports Server (NTRS)

    Bolten, John D.; Rodell, Matthew; Zaitchik, Benjamin; Ozdogan, Mutlu; Anderson, Martha; Bergaoui, Karim B.; Khalaf, Adla J.; McDonnell, Rachael A.

    2012-01-01

    The Middle East and North Africa (MENA) region is dominated by dry, warm deserts, areas of dense population, and inefficient use of fresh water resources. Due to the scarcity, high intensity, and short duration of rainfall in the MENA, the region is prone to hydro climatic extremes that are realized by devastating floods and times of drought. However, given its widespread water stress and the considerable demand for water, the MENA remains relatively poorly monitored. This is due in part to the shortage of meteorological observations and the lack of data sharing between nations. As a result, the accurate monitoring of the dynamics of the water cycle in the MENA is difficult. The Land Data Assimilation System for the MENA region (MENA LDAS) has been developed to provide regional, gridded fields of hydrological states and fluxes relevant for water resources assessments. As an extension of the Global Land Data Assimilation System (GLDAS), the MENA LDAS was designed to aid in the identification and evaluation of regional hydrological anomalies by synergistically combining the physically-based Catchment Land Surface Model (CLSM) with observations from several independent data products including soil-water storage variations from the Gravity Recovery and Climate Experiment (GRACE) and irrigation intensity derived from the Moderate Resolution Imaging Spectroradiometer (MODIS). In this fashion, we estimate the mean and seasonal cycle of the water budget components across the MENA.

  19. An Andean ice-core record of a Middle Holocene mega-drought in North Africa and Asia

    NASA Astrophysics Data System (ADS)

    Davis, Mary E.; Thompson, Lonnie G.

    An ice core from the Nevado Huascarán col in the Cordillera Blanca of northern Peru contains high-resolution time series of dust concentrations and size distributions since the end of the last glacial stage. A large dust peak, dated ˜4500 years ago, is contemporaneous with a widespread and prolonged drought that apparently extended from North Africa to eastern China, evidence of which occurs in historical, archeological and paleoclimatic records. This event may have been associated with several centuries of weak Asian/Indian/African monsoons, possibly linked with a protracted cooling in the North Atlantic. During the second half of the 20th century, high austral-summer dust concentrations in the Huascarán record are significantly correlated with atmospheric conditions, such as sea-level pressure and zonal wind velocities that are consistent with El Niño-Southern Oscillation (ENSO) and positive North Atlantic Oscillation (NAO) indices, and with aridity in North Africa, southwest Asia and the Middle East. Therefore, the dominant submicron fraction of the dust may have been transported by more intense northeasterly trade winds from the African dry regions across the tropical Atlantic during a period of frequent and/or intense ENSO activity. The proposed ENSO conditions that may have been linked with drought in the monsoon region may also have contributed to aridity in tropical South America, including the Cordillera Blanca.

  20. Evaluation of global and regional climate simulations over Africa

    NASA Astrophysics Data System (ADS)

    Nikulin, Grigory; Jones, Colin; Kjellström, Erik; Gbobaniyi, Emiola

    2013-04-01

    Two ensembles of climate simulations, one global and one regional, are evaluated and inter-compared over the Africa-CORDEX domain. The global ensemble includes eight coupled atmosphere ocean general circulation models (AOGCMs) from the CMIP5 project with horizontal resolution varying from about 1° to 3°, namely CanESM2, CNRM-CM5, HadGEM2-ES, NorESM1-M, EC-EARTH, MIROC5, GFDL-ESM2M and MPI-ESM-LR. In the regional ensemble all 8 AOGCMs are downscaled over the Africa-CORDEX domain at the Rossby Centre (SMHI) by a regional climate model - RCA4 at 0.44° resolution. The main focus is on ability of both global and regional ensembles to simulate precipitation in different climate zones of Africa. Precipitation climatology is characterized by seasonal means, inter-annual variability and by various characteristics of the rainy season: onset, cessation, mean intensity and intra-seasonal variability. To see potential benefits of higher resolution in the regional downscaling all precipitation statistics are inter-compared between the individual AOGCM-RCA4(AOGCM) pairs and between the two multi-model ensemble averages. A special attention in the study is on how the AOGCMs simulate teleconnection patterns of large-scale internal variability and how these teleconnection pattern are reproduced in the downscaled regional simulations.

  1. Do School Incentives and Accountability Measures Improve Skills in the Middle East and North Africa? The Cases of Jordan and Tunisia

    ERIC Educational Resources Information Center

    Shafiq, M. Najeeb

    2011-01-01

    There is general agreement that skill-enhancing school reforms in the Middle East and North Africa (MENA) region are necessary for economic, political and social reasons. Using student-level data from Jordan and Tunisia, this study assesses the relationship between skills and the following school incentive and accountability measures: pedagogical…

  2. Geology and petroleum resources of north-central and northeast Africa

    SciTech Connect

    Peterson, J.A.

    1986-05-01

    In north-central and northeast Africa, important petroleum accumulations exist in the Sirte basin of Libya, the western Sahara region of Algeria, the Pelagian platform offshore from eastern Tunisia, and in the Western Desert basin, Suez graben, and Nile delta in Egypt. Approximately 55 major fields (> 100 million BOE), of which 15 are giants (> 1 billion BOE), have been found in these provinces. Total estimated ultimate production from existing fields in 60 billion bbl of oil and 100 tcf of gas; estimated undiscovered petroleum resources are 26 billion bbl of oil and 93 tcf of gas. The post-Precambrian sedimentary basins of north Africa are related to the development of the Sahara platform during at least four main tectonic episodes (the Caledonian, Hercynian, Laramide, and Alpine cycles). The sedimentary cover of the platform, which includes rocks of all geologic systems, ranges from less than 1000 m (3300 ft) in the south to more than 9000 m (30,000 ft) along the Mediterranean coast. Paleozoic rocks are primarily continental and nearshore marine sandstone and shale, which are important reservoir and source rocks for petroleum in the central and western parts of the Sahara platform. Lower Mesozoic rocks were deposited in a continental and restricted marine environment, and contain thick beds of red beds and evaporites, including salt, which are important seals for oil and gas fields. Upper Mesozoic and Tertiary rocks are related to the development of the Mediterranean Tethys geosyncline and are characterized by numerous transgressive-regressive cycles of the Tethyan seaway. Marine carbonate and shale facies are dominant in the Upper Jurassic, Cretaceous, and lower Tertiary section of northern Libya, eastern Tunisia-Pelagian platform, and northern Egypt. Upper Tertiary beds are continental clastics on most of the platform, except near the Mediterranean.

  3. Faunistic and bibliographical inventory of the Psychodinae moth-flies of North Africa (Diptera, Psychodidae)

    PubMed Central

    Afzan, Hanan; Belqat, Boutaïna

    2016-01-01

    Abstract All published records for the 49 species of moth flies known from North Africa are reviewed and discussed: Morocco (27 species), Algeria (33 species), Tunisia (18 species) and Egypt (five species). In addition, records of seven species of Psychodinae new to the fauna of Morocco are added, of which three are new mentions for North Africa (Table 1) and one is a new record for Egypt. Telmatoscopus squamifer Tonnoir, 1922 is transferred to the genus Iranotelmatoscopus Ježek, 1987, comb. n. Satchelliella reghayana Boumezzough & Vaillant, 1987 is transferred to the genus Pneumia Enderlein, 1935, comb. n. Pneumia aberrans Tonnoir, 1922 is transferred to the subgenus Logima. PMID:27006599

  4. Sexual and bodily rights as human rights in the Middle East and North Africa.

    PubMed

    Ercevik Amado, Liz

    2004-05-01

    A regional workshop on sexual and bodily rights as human rights in the Middle East and North Africa was held in Malta in 2003, attended by 22 NGO representatives from Jordan, Egypt, Lebanon, Palestine, Tunisia, Morocco, Algeria, Turkey, Pakistan and USA. The meeting aimed to develop strategies for overcoming human rights violations in the region with reference to law and social and political practices. Session topics included sexuality and gender identity; sexuality and sexual health; sexuality and comparative penal law; sexual rights in international documents; advocacy and lobbying. Sexual rights, sexual health and education, sexual violence and adolescent sexuality were explored in depth, including taboos and emerging trends. Specific areas of concern included marital rape, early marriages, temporary marriages, sexual orientation, premarital and extramarital sexuality, honour crimes, female genital mutilation, unmarried mothers, adolescent sexuality, unwanted pregnancies and safe abortion, sexuality in education and health services. An analysis of civil codes, penal codes and personal status codes indicated a clear imperative for legal reform. Participants heard about efforts to promote the right to sexual orientation which have already been initiated in Lebanon, Turkey and Tunisia. Networking within the region and with counterparts in other regions in comparable situations and conditions was deemed essential. PMID:15242219

  5. Cryptic biodiversity in the cytogenome of bird-biting blackflies in North Africa.

    PubMed

    Adler, P H; Cherairia, M; Arigue, S F; Samraoui, B; Belqat, B

    2015-09-01

    Bird-biting blackflies in the Simulium (Eusimulium) aureum group (Diptera: Simuliidae) are widespread vectors of Leucocytozoon and Trypanosoma parasites. The polytene chromosomes of 619 larvae of the three nominal members of the S. aureum group in North Africa were evaluated cytogenetically for cryptic biodiversity. Seven chromosomal segregates were discovered among 29 populations in Algeria and Morocco. This diversity was based primarily on two chromosomal inversions, which have assumed unique roles in different lineages, including sex linkage, fixation, loss and autosomal polymorphism. Reproductive isolation was demonstrated for six of the seven segregates, doubling the number of species known in the area. Four species were linked with existing names: (a) Simulium mellah Giudicelli & Bouzidi, which is known only from North African high-salinity habitats; (b) Simulium petricolum (Rivosecchi), which is tentatively conspecific with continental European populations; (c) Simulium rubzovianum (Sherban) and its synonym Simulium latinum (Rubtsov), which is widely distributed from North Africa across Europe into Western Asia, and (d) Simulium velutinum (Santos Abreu) and its new synonym Simulium tenerificum Crosskey, which is restricted to North Africa and the Canary Islands. Of the remaining entities, two are new species precinctive to North Africa and one, known only from Morocco, is of undetermined taxonomic status. PMID:25801314

  6. Analysis and interpretation of MAGSAT anomalies over north Africa

    NASA Technical Reports Server (NTRS)

    Phillips, R. J.

    1985-01-01

    Crustal anomaly detection with MAGSAT data is frustrated by inherent resolving power of the data and by contamination from external and core fields. Quality of the data might be tested by modeling specific tectonic features which produce anomalies that fall within proposed resolution and crustal amplitude capabilities of MAGSAT fields. To test this hypothesis, north African hotspots associated with Ahaggar, Tibesti and Darfur were modeled as magnetic induction anomalies. MAGSAT data were reduced by subtracting external and core fields to isolate scalar and vertical component crustal signals. Of the three volcanic areas, only the Ahaggar region had an associated anomaly of magnitude above error limits of the data. Hotspot hypothesis was tested for Ahaggar by seeing if predicted magnetic signal matched MAGSAT anomaly. Predicted model magnetic signal arising from surface topography of the uplift and the Curie isothermal surface was calculated at MAGSAT altitudes by Fourier transform technique modified to allow for variable magnetization. Curie isotherm surface was calculated using a method for temperature distribution in a moving plate above a fixed hotspot. Magnetic signal was calculated for a fixed plate as well as a number of plate velocities and directions.

  7. Extensive nitrogen loss from permeable sediments off North-West Africa

    NASA Astrophysics Data System (ADS)

    Sokoll, Sarah; Lavik, Gaute; Sommer, Stefan; Goldhammer, Tobias; Kuypers, Marcel M. M.; Holtappels, Moritz

    2016-04-01

    The upwelling area off North-West Africa is characterized by high export production, high nitrate and low oxygen concentration in bottom waters. The underlying sediment consists of sands that cover most of the continental shelf. Due to their permeability sands allow for fast advective pore water transport and can exhibit high rates of nitrogen (N) loss via denitrification as reported for anthropogenically eutrophied regions. However, N loss from sands underlying naturally eutrophied waters is not well studied, and in particular, N loss from the North-West African shelf is poorly constrained. During two research cruises in April/May 2010/2011, sediment was sampled along the North-West African shelf and volumetric denitrification rates were measured in sediment layers down to 8 cm depth using slurry incubations with 15N-labeled nitrate. Areal N loss was calculated by integrating volumetric rates down to the nitrate penetration depth derived from pore water profiles. Areal N loss was neither correlated with water depth nor with bottom water concentrations of nitrate and oxygen but was strongly dependent on sediment grain size and permeability. The derived empirical relation between benthic N loss and grains size suggests that pore water advection is an important regulating parameter for benthic denitrification in sands and further allowed extrapolating rates to an area of 53,000 km2 using detailed sediment maps. Denitrification from this region amounts to 995 kt yr-1 (average 3.6 mmol m-2 d-1) which is 4 times higher than previous estimates based on diffusive pore water transport. Sandy sediments cover 50-60% of the continental shelf and thus may contribute significantly to the global benthic N loss.

  8. The African Geospatial Sciences Institute (agsi): a New Approach to Geospatial Training in North Africa

    NASA Astrophysics Data System (ADS)

    Oeldenberger, S.; Khaled, K. B.

    2012-07-01

    The African Geospatial Sciences Institute (AGSI) is currently being established in Tunisia as a non-profit, non-governmental organization (NGO). Its objective is to accelerate the geospatial capacity development in North-Africa, providing the facilities for geospatial project and management training to regional government employees, university graduates, private individuals and companies. With typical course durations between one and six months, including part-time programs and long-term mentoring, its focus is on practical training, providing actual project execution experience. The AGSI will complement formal university education and will work closely with geospatial certification organizations and the geospatial industry. In the context of closer cooperation between neighboring North Africa and the European Community, the AGSI will be embedded in a network of several participating European and African universities, e. g. the ITC, and international organizations, such as the ISPRS, the ICA and the OGC. Through a close cooperation with African organizations, such as the AARSE, the RCMRD and RECTAS, the network and exchange of ideas, experiences, technology and capabilities will be extended to Saharan and sub-Saharan Africa. A board of trustees will be steering the AGSI operations and will ensure that practical training concepts and contents are certifiable and can be applied within a credit system to graduate and post-graduate education at European and African universities. The geospatial training activities of the AGSI are centered on a facility with approximately 30 part- and full-time general staff and lecturers in Tunis during the first year. The AGSI will operate a small aircraft with a medium-format aerial camera and compact LIDAR instrument for local, community-scale data capture. Surveying training, the photogrammetric processing of aerial images, GIS data capture and remote sensing training will be the main components of the practical training courses

  9. Combustion particulate emissions in Africa: regional climate modeling and validation

    NASA Astrophysics Data System (ADS)

    Konare, A.; Liousse, C.; Guillaume, B.; Solmon, F.; Assamoi, P.; Rosset, R.; Gregoire, J. M.; Giorgi, F.

    2008-04-01

    Africa, as a major aerosol source in the world, plays a key role in regional and global geochemical cycles and climate change. Combustion carbonaceous particles, central in this context through their radiative and hygroscopic properties, require ad hoc emission inventories. These inventories must incorporate fossil fuels FF (industries, traffic,...), biofuels BF (charcoal, wood burning,... quite common in Africa for domestic use), and biomass burning BB regularly occurring over vast areas all over the African continent. This latter, subject to rapid massive demographic, migratory, industrial and socio-economic changes, requires continuous emission inventories updating, so as to keep pace with this evolution. Two such different inventories, L96 and L06 with main focus on BB emissions, have been implemented for comparison within the regional climate model RegCM3 endowed with a specialized carbonaceous aerosol module. Resulting modeled black carbon BC and organic carbon OC fields have been compared to past and present composite data set available in Africa. This data set includes measurements from intensive field campaigns (EXPRESSO 1996, SAFARI 2000), from the IDAF/DEBITS surface network and from MODIS, focused on selected west, central and southern African sub-domains. This composite approach has been adopted to take advantage of possible combinations between satellite high-resolution coverage of Africa, regional modeling, use of an established surface network, together with the patchy detailed knowledge issued from past short intensive regional field experiments. Stemming from these particular comparisons, one prominent conclusion is the need for continuous detailed time and spatial updating of combustion emission inventories apt to reflect the rapid transformations of the African continent.

  10. Seasonal drought forecast system for food-insecure regions of East Africa

    NASA Astrophysics Data System (ADS)

    Shukla, Shraddhanand; McNally, Amy; Husak, Greg; Funk, Chris

    2014-05-01

    In East Africa, agriculture is mostly rainfed and hence sensitive to interannual rainfall variability, and the increasing food and water demands of a growing population place further stresses on the water resources of this region. Skillful seasonal agricultural drought forecasts for this region can inform timely water and agricultural management decisions, support the proper allocation of the region's water resources, and help mitigate socio-economic losses. Here we describe the development and implementation of a seasonal drought forecast system that is being used for providing seasonal outlooks of agricultural drought in East Africa. We present a test case of the evaluation and applicability of this system for March-April-May growing season over equatorial East Africa (latitude 20 south to 80 North and 360 E to 460E) that encompasses one of the most food insecure and climatically and socio-economically vulnerable regions in East Africa. This region experienced famine as recently as in 2011. The system described here combines advanced satellite and re-analysis as well as station-based long term and real-time observations (e.g. NASA's TRMM, Infra-red remote sensing, Climate Forecast System Reanalysis), state-of-the-art dynamical climate forecast system (NCEP's Climate Forecast System Verison-2) and large scale land surface models (e.g. Variable Infiltration Capacity, NASA's Land Information System) to provide forecasts of seasonal rainfall, soil moisture and Water Requirement Satisfaction Index (WRSI) throughout the season - with an emphasis on times when water is the most critical: start of season/planting and the mid-season/crop reproductive phase. Based on the hindcast assessment of this system, we demonstrate the value of this approach to the US Agency for International Development (USAID)'s efforts to mitigate future losses of lives and economic losses by allowing a proactive approach of drought management that includes early warning and timely action.

  11. CD4+ T cell recovery during suppression of HIV replication: an international comparison of the immunological efficacy of antiretroviral therapy in North America, Asia and Africa

    PubMed Central

    Geng, Elvin H; Neilands, Torsten B; Thièbaut, Rodolphe; Bosco Bwana, Mwebesa; Nash, Denis; Moore, Richard D; Wood, Robin; Marcel Zannou, Djimon; Althoff, Keri N; Lian Lim, Poh; Nachega, Jean B; Easterbrook, Philippa J; Kambugu, Andrew; Little, Francesca; Nakigozi, Gertrude; Nakanjako, Damalie; Kiggundu, Valerian; Chung Ki Li, Patrick; Bangsberg, David R; Fox, Matthew P; Prozesky, Hans W; Hunt, Peter W; Davies, Mary-Ann; Reynolds, Steven J; Egger, Matthias; Yiannoutsos, Constantin T; Vittinghoff, Eric V; Deeks, Steven G; Martin, Jeffrey N

    2015-01-01

    Background: Even among HIV-infected patients who fully suppress plasma HIV RNA replication on antiretroviral therapy, genetic (e.g. CCL3L1 copy number), viral (e.g. tropism) and environmental (e.g. chronic exposure to microbial antigens) factors influence CD4 recovery. These factors differ markedly around the world and therefore the expected CD4 recovery during HIV RNA suppression may differ globally. Methods: We evaluated HIV-infected adults from North America, West Africa, East Africa, Southern Africa and Asia starting non-nucleoside reverse transcriptase inhibitor-based regimens containing efavirenz or nevirapine, who achieved at least one HIV RNA level <500/µl in the first year of therapy and observed CD4 changes during HIV RNA suppression. We used a piecewise linear regression to estimate the influence of region of residence on CD4 recovery, adjusting for socio-demographic and clinical characteristics. We observed 28 217 patients from 105 cohorts over 37 825 person-years. Results: After adjustment, patients from East Africa showed diminished CD4 recovery as compared with other regions. Three years after antiretroviral therapy initiation, the mean CD4 count for a prototypical patient with a pre-therapy CD4 count of 150/µl was 529/µl [95% confidence interval (CI): 517–541] in North America, 494/µl (95% CI: 429–559) in West Africa, 515/µl (95% CI: 508–522) in Southern Africa, 503/µl (95% CI: 478–528) in Asia and 437/µl (95% CI: 425–449) in East Africa. Conclusions: CD4 recovery during HIV RNA suppression is diminished in East Africa as compared with other regions of the world, and observed differences are large enough to potentially influence clinical outcomes. Epidemiological analyses on a global scale can identify macroscopic effects unobservable at the clinical, national or individual regional level. PMID:25859596

  12. A General Survey of Religious Concepts and Art of North, East, South, and West Africa.

    ERIC Educational Resources Information Center

    Stewart, Rohn

    This paper, a summary of a multi-carousel slide presentation, reviews literature on the cultures, religions, and art of African people. Before focusing on West Africa, highlights of the lifestyles, religions, and icons of non-maskmaking cultures of North, West and South African people are presented. Clarification of West African religious concepts…

  13. Assessment of undiscovered conventional oil and gas resources of North Africa, 2012

    USGS Publications Warehouse

    Schenk, Christopher J.; Klett, Timothy R.; Whidden, Katherine J.; Kirschbaum, Mark A.; Charpentier, Ronald R.; Cook, Troy A.; Brownfield, Michael E.; Pitman, Janet K.

    2013-01-01

    Using a geology-based assessment methodology, the U.S. Geological Survey estimated means of 19 billion barrels of technically recoverable undiscovered conventional oil and 370 trillion cubic feet of undiscovered conventional natural gas resources in 8 geologic provinces of North Africa.

  14. Rural Development in Africa: A Bibliography (Part II: North, South, West). Training & Methods Series, Number 17.

    ERIC Educational Resources Information Center

    Wisconsin Univ., Madison. Land Tenure Center.

    Compiled in December 1971, this bibliography lists approximately 940 books, journals, periodicals, and unpublished mimeographs dealing with rural development in north, west, and southern Africa. All materials are dated between 1953 and 1971. Entries are listed by country under the following headings: agriculture, economic affairs, social affairs,…

  15. North Pole Region of the Moon as Seen by Clementine

    NASA Technical Reports Server (NTRS)

    1995-01-01

    Lunar mosaic of 1500 Clementine images of the north polar region of the moon. The projection is orthographic centered on the north pole. The polar regions of the moon are of special interest because of the postulated occurrence of ice in permanently shadowed areas. The north pole of the moon is absent of the very rugged terrain seen at the south pole.

  16. Concentrating solar power in Europe, the Middle East and North Africa: achieving its potential

    NASA Astrophysics Data System (ADS)

    Pitz-Paal, R.; Amin, A.; Bettzüge, M.; Eames, P.; Fabrizi, F.; Flamant, G.; Garcia Novo, F.; Holmes, J.; Kribus, A.; van der Laan, H.; Lopez, C.; Papagiannakopoulos, P.; Pihl, E.; Smith, P.; Wagner, H.-J.

    2012-10-01

    Concentrating solar power (CSP) is a commercially available renewable energy technology capable of harnessing the immense solar resource in Southern Europe, the Middle East and North Africa (the MENA region), and elsewhere. This paper summarises the findings of a study by the European Academies Science Advisory Council which has examined the current status and development challenges of CSP, and consequently has evaluated the potential contribution of CSP in Europe and the MENA region to 2050. It identifies the actions that will be required by scientists, engineers, policy makers, politicians, business and investors alike, to enable this vast solar resource to make a major contribution to establishing a sustainable energy system. The study concludes that cost reductions of 50-60% in CSP electricity may reasonably be expected in the next 10-15 years, enabling the technology to be cost competitive with fossil-fired power generation at some point between 2020 and 2030. Incorporation of storage delivers added value in enabling CSP to deliver dispatchable power. Incentive schemes will be needed in Europe and MENA countries to enable this point to be achieved. Such schemes should reflect the true value of electricity to the grid, effectively drive R&D, and ensure transparency of performance and cost data.

  17. Metallogenic evolution of uranium deposits in the Middle East and North Africa deposits

    NASA Astrophysics Data System (ADS)

    Howari, Fares; Goodell, Philip; Salman, Abdulaty

    2016-02-01

    This paper is briefly involved in classification and distributions of the Middle East and North Africa (MENA) uranium deposits. The study of these mineral systems can significantly contribute to our further understanding of the metallogeny of known and poorly explored deposits. This provides contribution to, and further enhancement of, current classifications and metallogenic models of uranium systems, allowing researchers to emphasize on unknown or poorly studied mineral systems found in MENA. The present study identified eight metallogenic types of uranium associated with: 1) the Archean rocks and intra-cratonic basins, 2) the Pan-African granites and rhyolites which are characterized by igneous activity, 3) Phanerozoic (Paleozoic) clastics, these deposits are the sedimentological response to Pan African magmatism, 4) Mesozoic (basal) clastics type e.g. Nubia sandstones which are characterized by uranium minerals, 5) regional sedimentary phosphate deposits which are categorized as geosynclinal, or continental margin deposits, on the shelf of the Tethys Ocean, 6) Cenozoic Intracratonic Felsic Magmatism of the Tibesti and Hoggar, and the sandstone U deposits of adjoining Niger. These are similar to the Pan-African magmatism metallogenic, 7) Calcretes, and 8) Resistate minerals which are often enriched in rare earth elements, sometimes including uranium. They are thus sometimes considered as U resources but poorly explored in the MENA region. These metallogenic types are described and discussed in the current paper.

  18. HIV/AIDS among pastoralists and refugees in north-east Africa: a neglected problem.

    PubMed

    Serbessa, Mirgissa Kaba; Mariam, Damen Haile; Kassa, Afework; Alwan, Fathia; Kloos, Helmut

    2016-03-01

    The eight member states (Djibouti, Eritrea, Ethiopia, Kenya, Somalia, South Sudan, Sudan and Uganda) of the Intergovernmental Authority for Development (IGAD) have the largest proportions of cross-border mobile pastoralists and refugees in Africa. Although all IGAD countries have had national HIV/AIDS prevention, care and treatment programmes since the late 1980s, the IGAD Regional HIV & AIDS Partnership Program was (IRAPP) established in 2007 to mitigate the challenges of HIV among neglected pastoral and refugee communities. This article assesses vulnerability of pastoralists and refugee communities to HIV and interventions targeting these groups in the IGAD countries. Outcomes from this study may serve as a baseline for further research and to improve interventions. Published articles were accessed through web searches using PubMed and Google Scholar engines and unpublished documents were collected manually. The search terms were HIV risk behaviour, vulnerability, HIV prevalence and interventions, under the headings pastoralists, refugees, IGAD and north-east Africa for the period 2001-2014. Of the 214 documents reviewed, 78 met the inclusion criteria and were included. Most HIV/AIDS related studies focusing of pastoral communities in IGAD countries were found to be limited in scope and coverage but reveal precarious situations. Sero-prevalence among various pastoral populations ranged from 1% to 21% in Ethiopia, Kenya, Somalia and Uganda and from 1% to 5% among refugees in Sudan, Kenya and Uganda. Socioeconomic, cultural, logistic, infrastructure and programmatic factors were found to contribute to continuing vulnerability to HIV. Interventions need to be further contextualised to the needs of those impoverished populations and integrated into national HIV/AIDS programmes. HIV/AIDS remains a major public health concern among the pastoral and refugee communities of IGAD countries. This calls for IGAD to collaborate with national and international partners in

  19. Infection of Ixodes ricinus (Acari: Ixodidae) by Borrelia burgdorferi sensu lato in North Africa

    USGS Publications Warehouse

    Zhioua, E.; Bouattour, A.; Hu, C.M.; Gharbi, M.; Aeschliman, A.; Ginsberg, H.S.; Gern, L.

    1999-01-01

    Free-living adult Ixodes ricinus L. were collected in Amdoun, situated in the Kroumiry mountains in northwestern Tunisia (North Africa). Using direct fluorescence antibody assay, the infection rate of field-collected I. ricinus by Borrelia burgdorferi sensu lato was 30.5% (n = 72). No difference in infection rate was observed between male and female ticks. Spirochetes that had been isolated from I. ricinus from Ain Drahim (Kroumiry Mountains) in 1988 were identified as Borrelia lusitaniae (formerly genospecies PotiB2). This is the first identification of a genospecies of Borrelia burgdorferi sensu lato from the continent of Africa.

  20. The spatial distribution of mineral dust and its shortwave radiative forcing over North Africa. Modeling sensitivities to dust emissions and aerosol size treatments

    SciTech Connect

    Zhao, Chun; Liu, Xiaohong; Leung, Lai-Yung R.; Johnson, Ben; McFarlane, Sally A.; Gustafson, William I.; Fast, Jerome D.; Easter, Richard C.

    2010-09-20

    A fully coupled meteorology-chemistry-aerosol model (WRF-Chem) with the implementation of two dust emission schemes (GOCART and DUSTRAN) into two aerosol models (MADE/SORGAM and MOSAIC) is applied over North Africa to investigate the modeling sensitivities to dust emissions and aerosol size treatments in simulating mineral dust and its shortwave (SW) radiative forcing. Model results of the spatial distribution of mineral dust and its radiative forcing are evaluated using measurements from the AMMA SOP0 campaign in January and February of 2006 over North Africa. Our study suggests that the size distribution of emitted dust can result in significant differences (up to 100%) in simulating mineral dust and its SW radiative forcing. With the same dust emission and dry deposition processes, two aerosol models, MADE/SORGAM and MOSAIC, can yield large difference in size distributions of dust particles due to their different aerosol size treatments using modal and sectional approaches respectively. However, the difference between the two aerosol models in simulating the mass concentrations and the SW radiative forcing of mineral dust is small (< 10%). The model simulations show that mineral dust increases AOD by a factor of 2, heats the lower atmosphere (1-3 km) with a maximum rate of 0.7±0.5 K day-1 below 1 km, and reduces the downwelling SW radiation by up to 25 W m-2 on 24-hour average at surface, highlighting the importance of including dust radiative impact in understanding the regional climate of North Africa. When compared to the available measurements, WRF-Chem simulations can generally capture the measured features of mineral dust and its radiative properties over North Africa, suggesting that the model can be used to perform more extensive simulations of regional climate over North Africa.

  1. Extracting Uplift Rate Histories From Longitudinal River Profiles: Examples From North America and Africa

    NASA Astrophysics Data System (ADS)

    Roberts, Gareth G.; White, Nicky; Paul, Jonathan

    2013-04-01

    ~ 0.06 mm/yr. A final and smaller phase of uplift commenced ~ 5 Ma. These distinct phases of uplift are corroborated by spot estimates of palaeoaltimetry, timed growth of relief, thermochronometric data and by stratigraphic evidence of pulsed clastic efflux delivered to the Gulf of Mexico. An episodic uplift history is consistent with punctuated dynamic support of a large region, which is currently centred on Yellowstone. Inversion of the Congo, Nile, Niger, Ogooue, Orange, Zambezi rivers and their major tributaries indicates that domal swells in Africa have experienced a staged uplift history. The West African margin has experienced at least two phases of uplift during the last 30 Ma. Uplift in Afar began ~ 35 Ma. The Hoggar and Tibesti swells, in central North Africa, have an older history of uplift. These results are consistent with a staged magmatic history, delivery of sediment to the continental margins and stratigraphic observations, which suggest that the African landscape is responding to convection in the mantle.

  2. Chasma Boreale in the North Polar Region

    NASA Technical Reports Server (NTRS)

    2006-01-01

    This images shows a Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) full-resolution 'targeted image' of the edge of Mars' north polar cap. The region in the image, Chasma Boreale, is a valley several kilometers or miles deep that cuts about 400 kilometers (about 250 miles) into the edge of the cap.

    This image was acquired at 0851 UTC (4:51 a.m. EDT) on Oct. 1, 2006, near 84.6 degrees north latitude, 3.6 degrees east longitude. It covers an area about 13 kilometers (8 miles) long and, at the narrowest point, about 9 kilometers (5.6 miles) wide. At the center of the image the spatial resolution is as good as 18 meters (60 feet) per pixel. The image was taken in 544 colors covering wavelengths of 0.36 to 3.92 micrometers. Two renderings of the data are shown here, both draped over topography without vertical exaggeration, and then viewed from a perspective diagonally above the site. The top view is an approximately true-color representation. The bottom view, constructed from infrared wavelengths, shows strength of the spectral signature of ice. Brighter areas are rich in ice, and dark areas have little ice.

    The polar cap has long been recognized to contain layers composed of dust and ice, and hence has been named the polar layered deposit. This sits atop an underlying 'basal unit.' The upper part of the basal unit is dark at visible wavelengths and steeply sloped, whereas the lower part of the basal unit is brighter, redder, and layered like the polar layered deposits. The chasma floor is cratered, and in the foreground it is covered by dunes that are outliers of a north polar sand sea that surrounds the polar cap. The polar layered deposits and the basal unit form a steeply sloping scarp about 1.1 kilometers (0.7 miles) high.

    CRISM's image of this region shows a number of previously unrecognized characteristics of the polar layered deposits and the basal unit. First, the ice-rich polar layered deposits exhibit coherent banding both at

  3. Hydrated Units in the Martian North Polar Region

    NASA Astrophysics Data System (ADS)

    Horgan, B. H. N.; Bell, J. F.; Noe Dobrea, E. Z.; Cloutis, E. A.; Bailey, D. T.; Craig, M. A.; Stewart, L.

    2008-03-01

    We show that the hydration signature detected in Olympia Undae extends to other units in the north polar region, including nearly the entirety of the north polar erg, dunes within reentrants in Planum Boreum, and in the north polar layered deposits.

  4. Challenges of diagnosis and management of axial spondyloarthritis in North Africa and the Middle East: An expert consensus.

    PubMed

    Hammoudeh, Mohammed; Abdulaziz, Sultana; Alosaimi, Hanan; Al-Rayes, Hanan; Aldeen Sarakbi, Hussam; Baamer, Matouqa; Baraliakos, Xenofon; Dahou Makhloufi, Chafia; Janoudi, Nahid; Shirazy, Khalid; Sieper, Joachim; Sukhbir, Uppal

    2016-04-01

    Axial spondyloarthritis (SpA) is a spectrum of inflammatory disease with stages characterized by both nonradiographic and radiographic sacroiliitis. Nonradiographic axial SpA is associated with health-related quality-of-life impairment and may progress to ankylosing spondylitis. Axial SpA has a low prevalence in some countries in North Africa and the Middle East, and pooling of data and resources is needed to increase understanding of the regional picture. Early diagnosis and effective treatment are required to reduce disease burden and prevent progression. Anti-TNF therapy is recommended for patients with persistently high disease activity despite conventional treatment, and has been shown to be effective in patients without radiographic damage. Diagnostic delays can be an obstacle to early treatment and appropriate referral strategies are needed. In some countries, restricted access to magnetic resonance imaging and anti-TNF agents presents a challenge. In this article, a group of experts from North Africa and the Middle East evaluated the diagnosis and management of axial SpA with particular reference to this region. PMID:26811411

  5. Azimuthal anisotropy beneath north central Africa from shear wave splitting analyses

    NASA Astrophysics Data System (ADS)

    Lemnifi, Awad A.; Liu, Kelly H.; Gao, Stephen S.; Reed, Cory A.; Elsheikh, Ahmed A.; Yu, Youqiang; Elmelade, Abdala A.

    2015-04-01

    This study represents the first multistation investigation of azimuthal anisotropy beneath the interior of north central Africa, including Libya and adjacent regions, using shear wave splitting (SWS) analysis. Data used in the study include recently available broadband seismic data obtained from 15 stations managed by the Libyan Center for Remote Sensing and Space Science, and those from five other stations at which data are publicly accessible. A total of 583 pairs of high-quality SWS measurements utilizing the PKS, SKKS, and SKS phases demonstrate primarily N-S fast orientations with an average splitting delay time of approximately 1.2 s. An absence of periodic azimuthal variation of the observed splitting parameters indicates the presence of simple anisotropy, and lack of correlation between surficial features and the splitting parameters suggests that the origin of the observed anisotropy is primarily asthenospheric. This conclusion is enhanced by nonperiodic azimuthal variation of the splitting parameters observed at one of the stations located near the boundary of areas with different anisotropic properties. We interpret the observed anisotropy to be the consequence of northward movement of the African plate relative to the asthenosphere toward the Hellenic and Calabrian subduction zones. Local variance in fast orientations may be attributable to flow deflection by the northern edge of the African continental root. The observations provide critical and previously lacking constraints on mantle dynamic models in the vicinity of the convergent boundary between the African and Eurasian plates.

  6. Consanguinity and genetic diseases in North Africa and immigrants to Europe.

    PubMed

    Anwar, Wagida A; Khyatti, Meriem; Hemminki, Kari

    2014-08-01

    Endemic diseases are caused by environmental and genetic factors. While in this special issue several chapters deal with environmental factors, including infections, the present focus is on genetic causes of disease clustering due to inbreeding and recessive disease mechanisms. Consanguinity is implying sharing of genetic heritage because of marriage between close relatives originating from a common ancestor. With limited natural selection, recessive genes may become more frequent in an inbred compared with an outbred population. Consanguinity is common in North Africa (NA), and the estimates range from 40 to 49% of all marriages in Tunisia and 29-33% in Morocco. As a consequence, recessive disorders are common in the NA region, and we give some examples. Thalassaemia and sickle cell disease/anaemia constitute the most common inherited recessive disorders globally and they are common in NA, but with immigration they have spread to Europe and to other parts of the world. Another example is familial Mediterranean fever, which is common in the Eastern Mediterranean area. With immigrantion from that area to Sweden, it has become the most common hereditary autoinflammatory disease in that country, and there is no evidence that any native Swede would have been diagnosed with this disease. The examples discussed in this chapter show that the historic movement of populations and current immigration are influencing the concept of 'endemic' disease. PMID:25107999

  7. Treated Wastewater's Potential for Improving Water and Food Security in the Middle East and North Africa

    NASA Astrophysics Data System (ADS)

    Dare, A. E.

    2014-12-01

    The Middle East and North Africa (MENA) contains just 1% of the world's freshwater; however, even in the very arid countries of the Gulf region, high quality treated wastewater rarely sees a productive use. As countries deal with growing populations and strive for increased food security, freshwater alone cannot be relied upon to meet these demands. This research identifies best practices from the MENA for reusing treated wastewater in agricultural production, and calculates the potential of treated wastewater for increasing food production in select countries. Drawing upon both published and original treated wastewater quality data for locations in the MENA, the annual volume of treated wastewater produced, and crop water demands, estimates for potential crop production from treated wastewater are calculated. The volume of wastewater treated annually is equivalent to 10-40% of agricultural withdrawals in most MENA countries. Irrigation by treated wastewater has significant potential to impact water and food security by reducing agricultural water withdrawals and increasing domestic food production. Such initiatives require application of best management practices, such as transparent monitoring and evaluation of reuse projects for public and environmental health risks, and support from both farmers and policy makers.

  8. The state of harm reduction in the Middle East and North Africa: A focus on Iran and Morocco.

    PubMed

    Himmich, Hakima; Madani, Navid

    2016-05-01

    HIV/AIDS and hepatitis C among people who inject drugs are on the rise in the Middle East and North Africa (MENA) region. But the regional response to the epidemic falls short both in terms of the quality and scale of response. From the threat of the death sentence for drug offenses to the burden of refugees fleeing conflict, there are many legal, political and social barriers that hinder the introduction and expansion of harm reduction in the region. However Iran and Morocco are two pioneering countries and over the last decade they have been providing evidence that harm reduction is feasible and acceptable in MENA. Using different approaches, these two countries have overcome various obstacles and encouraged discussion and collaboration among stakeholders, including government, health professionals, civil society and community-based organizations. In so doing they have created an enabling environment to endorse a national harm strategy. PMID:27012581

  9. Oil and gas developments in North Africa in 1984

    SciTech Connect

    Michel, R.C.

    1985-10-01

    Petroleum rights in the 6 North African countries (Algeria, Egypt, Libya, Morocco, Sudan, and Tunisia) covered in this paper were 1,906,065 km/sup 2/ at the end of 1984. An increase of 4.6% from the 1,821,966 km/sup 2/ in force at the end of 1983. This increase is due to large awards in the Sudan despite significant relinquishments elsewhere. Seismic surveys conducted during 1984 decreased to about 510.5 crew-months onshore and 29.5 crew-months offshore. However, exploration in and off Egypt was higher compared to 1983. Exploratory drilling was lower, with only 125 wells drilled compared to 179 tests completed in 1983. The main decrease was in Egypt and Sudan, but drilling in Libya resulted in 20 more completions. A significant oil discovery was made in the offshore part of the Sirte basin, off southwest Cyrenaica. The success rate in North America ranged from 19% to 50% (Libya). Development drilling increased during 1984, as higher activity appears to have taken place in 3 countries. Oil production, with an estimated daily rate of 2,952,570 bbl, was 2.8% from 1983 (2,871,460 BOPD). In Egypt, 7 fields located in the Gulf of Suez area went on stream during the year. Political unrest, which prevailed in southern Sudan during most of 1984, will likely delay the start-up of production in several fields. No statistics are available on gas production in North African countries. 9 figures, 27 tables.

  10. A Preliminary Look at the Crust and Upper Mantle of North Africa Using Libyan Seismic Data

    SciTech Connect

    Pasyanos, M

    2005-08-05

    In recent years, LLNL has been developing methods to jointly invert both surface wave dispersion data and teleseismic receiver functions. The technique holds great promise in accurately estimating seismic structure, including important tectonic parameters such as basin thickness, crustal thickness, upper mantle velocity, etc. We proposed applying this method to some recently available data from several Libyan stations, as we believe the technique has not been applied to any stations in Libya. The technique holds the promise of improving our understanding of the crust and upper mantle in Libya and North Africa. We recently requested seismic data from stations GHAR (Gharyan) and MARJ (Al Marj) in Libya for about 20 events. The events were large events at regional distances suitable for making dispersion measurements. An example of waveforms recorded at the two stations from an earthquake in Italy is shown in Figure 1. The paths traverse the Ionian Sea. Notice the slow short period group velocities of the surface waves across the Mediterranean, particularly to the easternmost station MARJ. However, because of data availability, signal-to-noise ratio, etc. we were unable to make measurements for every one of these events at both stations. Figure 2 shows a map of paths for 20 sec Rayleigh waves in the eastern Mediterranean region. Paths measured at the two Libyan stations are shown in green. Rayleigh wave dispersion measurements at 20 sec period are sensitive to velocities in the upper 20 km or so, and reveal sediment thickness, crustal velocity, and crustal thickness. Tomographic inversions reveal the sharp group velocity contrast between regions with deep sedimentary basins and those without. Figure 3, the result of an inversion made before adding the new dispersion measurements, shows slow group velocities in the Black Sea, Adriatic Sea, and Eastern Mediterranean. In general, these features correspond well with the sediment thickness model from Laske, shown in Figure

  11. Early initiation of antiretroviral treatment: Challenges in the Middle East and North Africa

    PubMed Central

    Sardashti, Sara; Samaei, Mehrnoosh; Firouzeh, Mona Mohammadi; Mirshahvalad, Seyed Ali; Pahlaviani, Fatemeh Golsoorat; SeyedAlinaghi, SeyedAhmad

    2015-01-01

    New World Health Organization guidelines recommend the initiation of antiretroviral treatment (ART) for asymptomatic patients with CD4+ T-cell counts of ≤ 500 cells/mm3. Substantial reduction of human immunodeficiency virus (HIV) transmission is addressed as a major public health outcome of this new approach. Middle East and North Africa (MENA), known as the area of controversies in terms of availability of comprehensive data, has shown concentrated epidemics among most of it’s at risk population groups. Serious challenges impede the applicability of new guidelines in the MENA Region. Insufficient resources restrict ART coverage to less than 14%, while only one fourth of the countries had reportable data on patients’ CD4 counts at the time of diagnosis. Clinical guidelines need to be significantly modified to reach practical utility, and surveillance systems have not yet been developed in many countries of MENA. Based on available evidence in several countries people who inject drugs and men who have sex with men are increasingly vulnerable to HIV and viral hepatitis, while their sexual partners - either female sex workers or women in monogamous relationships with high-risk men - are potential bridging populations that are not appropriately addressed by regional programs. Research to monitor the response to ART among the mentioned groups are seriously lacking, while drug resistant HIV strains and limited information on adherence patterns to treatment regimens require urgent recognition by health policymakers. Commitment to defined goals in the fight against HIV, development of innovative methods to improve registration and reporting systems, monitoring and evaluation of current programs followed by cost-effective modifications are proposed as effective steps to be acknowledged by National AIDS Programs of the countries of MENA Region. PMID:25964878

  12. A large abelisaurid (Dinosauria, Theropoda) from Morocco and comments on the Cenomanian theropods from North Africa.

    PubMed

    Chiarenza, Alfio Alessandro; Cau, Andrea

    2016-01-01

    We describe the partially preserved femur of a large-bodied theropod dinosaur from the Cenomanian "Kem Kem Compound Assemblage" (KKCA) of Morocco. The fossil is housed in the Museo Geologico e Paleontologico "Gaetano Giorgio Gemmellaro" in Palermo (Italy). The specimen is compared with the theropod fossil record from the KKCA and coeval assemblages from North Africa. The combination of a distally reclined head, a not prominent trochanteric shelf, distally placed lesser trochanter of stout, alariform shape, a stocky shaft with the fourth trochanter placed proximally, and rugose muscular insertion areas in the specimen distinguishes it from Carcharodontosaurus, Deltadromeus and Spinosaurus and supports referral to an abelisaurid. The estimated body size for the individual from which this femur was derived is comparable to Carnotaurus and Ekrixinatosaurus (up to 9 meters in length and 2 tons in body mass). This find confirms that abelisaurids had reached their largest body size in the "middle Cretaceous," and that large abelisaurids coexisted with other giant theropods in Africa. We review the taxonomic status of the theropods from the Cenomanian of North Africa, and provisionally restrict the Linnean binomina Carcharodontosaurus iguidensis and Spinosaurus aegyptiacus to the type specimens. Based on comparisons among the theropod records from the Aptian-Cenomanian of South America and Africa, a partial explanation for the so-called "Stromer's riddle" (namely, the coexistence of many large predatory dinosaurs in the "middle Cretaceous" record from North Africa) is offered in term of taphonomic artifacts among lineage records that were ecologically and environmentally non-overlapping. Although morphofunctional and stratigraphic evidence supports an ecological segregation between spinosaurids and the other lineages, the co-occurrence of abelisaurids and carcharodontosaurids, two groups showing several craniodental convergences that suggest direct resource competition

  13. A large abelisaurid (Dinosauria, Theropoda) from Morocco and comments on the Cenomanian theropods from North Africa

    PubMed Central

    2016-01-01

    We describe the partially preserved femur of a large-bodied theropod dinosaur from the Cenomanian “Kem Kem Compound Assemblage” (KKCA) of Morocco. The fossil is housed in the Museo Geologico e Paleontologico “Gaetano Giorgio Gemmellaro” in Palermo (Italy). The specimen is compared with the theropod fossil record from the KKCA and coeval assemblages from North Africa. The combination of a distally reclined head, a not prominent trochanteric shelf, distally placed lesser trochanter of stout, alariform shape, a stocky shaft with the fourth trochanter placed proximally, and rugose muscular insertion areas in the specimen distinguishes it from Carcharodontosaurus, Deltadromeus and Spinosaurus and supports referral to an abelisaurid. The estimated body size for the individual from which this femur was derived is comparable to Carnotaurus and Ekrixinatosaurus (up to 9 meters in length and 2 tons in body mass). This find confirms that abelisaurids had reached their largest body size in the “middle Cretaceous,” and that large abelisaurids coexisted with other giant theropods in Africa. We review the taxonomic status of the theropods from the Cenomanian of North Africa, and provisionally restrict the Linnean binomina Carcharodontosaurus iguidensis and Spinosaurus aegyptiacus to the type specimens. Based on comparisons among the theropod records from the Aptian-Cenomanian of South America and Africa, a partial explanation for the so-called “Stromer’s riddle” (namely, the coexistence of many large predatory dinosaurs in the “middle Cretaceous” record from North Africa) is offered in term of taphonomic artifacts among lineage records that were ecologically and environmentally non-overlapping. Although morphofunctional and stratigraphic evidence supports an ecological segregation between spinosaurids and the other lineages, the co-occurrence of abelisaurids and carcharodontosaurids, two groups showing several craniodental convergences that suggest direct

  14. Revisiting a hoary chestnut: the nature of early cattle domestication in North-East Africa

    PubMed Central

    Brass, Michael

    2013-01-01

    Summary It has been almost three decades since the Wendorf & Schild-Andrew Smith debate over the timing and location of domesticated cattle in North Africa reached its climax. The time is now appropriate for a review of the old models in light of subsequent anatomical and genetic data which have come to light. This article summarises the main issues and models, and attempts to provide suggestions for future investigations. PMID:24077927

  15. Assessment of undiscovered oil and gas resources of the Sud Province, north-central Africa

    USGS Publications Warehouse

    Brownfield, M.E.; Klett, T.R.; Schenk, C.J.; Charpentier, R.R.; Cook, T.A.; Pollastro, R.M.; Tennyson, M.E.

    2011-01-01

    The Sud Province located in north-central Africa recently was assessed for undiscovered, technically recoverable oil, natural gas, and natural gas liquids resources as part of the U.S. Geological Survey's (USGS) World Oil and Gas Assessment. Using a geology-based assessment methodology, the USGS estimated mean volumes of 7.31 billion barrels of oil, 13.42 trillion cubic feet of natural gas, and 353 million barrels of natural gas liquids.

  16. Assessment of undiscovered oil and gas resources of the Chad Basin Province, North-Central Africa

    USGS Publications Warehouse

    Brownfield, Michael E.; Schenk, Christopher J.; Charpentier, Ronald R.; Klett, Timothy R.; Cook, Troy A.; Pollastro, Richard M.; Tennyson, Marilyn E.

    2010-01-01

    The Chad Basin Province located in north-central Africa recently was assessed for undiscovered, technically recoverable oil, natural gas, and natural gas liquids resources as part of the U.S. Geological Survey's (USGS) World Oil and Gas Assessment. Using a geology-based assessment methodology, the USGS estimated mean volumes of 2.32 billion barrels of oil, 14.65 trillion cubic feet of natural gas, and 391 million barrels of natural gas liquids.

  17. How important are atmospheric depressions and mobile cyclones for emitting mineral dust aerosol in North Africa?

    NASA Astrophysics Data System (ADS)

    Fiedler, S.; Schepanski, K.; Knippertz, P.; Heinold, B.; Tegen, I.

    2014-09-01

    This study presents the first quantitative estimate of the mineral dust emission associated with atmospheric depressions and mobile cyclones in North Africa. Atmospheric depressions are automatically tracked at 925 hPa based on ERA-Interim data from the European Centre for Medium-Range Weather Forecasts for 1989-2008. A set of filter criteria is applied to identify mobile cyclones, i.e. migrating and long-lived cyclones. The shorter term cyclone is used as a synonym for mobile cyclones. Dust emission is calculated with a dust emission model driven by 10 m winds and soil moisture from ERA-Interim. Emission peaks during winter and spring with spatial averages of 250-380 g m-2 per month. Comparison of the dust source activation frequency from the model against SEVIRI satellite observation shows a good agreement in the Bodélé Depression but differences in the north and west of North Africa. Depressions are abundant, particularly in summer when the Saharan heat low is situated over West Africa and during spring in the lee of the Atlas Mountains. Up to 90% (55% annually and spatially averaged) of dust emission occurs within 10 degrees of these depressions, with embedded mechanisms such as nocturnal low-level jets playing a role. Cyclones are rarer and occur primarily north of 20° N in spring in agreement with previous studies and over summertime West Africa consistent with near-surface signatures of African Easterly Waves. Dust emission within 10 degrees of cyclones peaks over Libya with up to 25% in spring. Despite the overall small contribution of 4% annually and spatially averaged, cyclones coincide with particularly intense dust emission events exceeding the climatological mean by a factor of four to eight. Soil moisture weakens dust emission during cyclone passage by about 10%.

  18. What is the impact of Harmattan surges on desert dust emission in North Africa?

    NASA Astrophysics Data System (ADS)

    Fiedler, Stephanie; Kaplan, Michael L.; Knippertz, Peter

    2015-04-01

    Desert dust aerosols have important implications in the Earth system, but their emission amount has a large model uncertainty. Improving the most important meteorological processes for dust-emitting winds helps to reduce this uncertainty. However, the dominant meteorological mechanisms for the large dust emission during spring remain unclear. This time of year is characterized by mobile, long-lived cyclones and Harmattan surges which are capable to uplift dust aerosol for long-range atmospheric transport. Emission near to the centre of mobile, long-lived cyclones are associated with a small mass of dust emission over the northern Sahara in spring, despite their most frequent occurrence in this season. Harmattan surges are proposed to be more efficient in emitting dust aerosol in spring. These events manifest themselves as a postfrontal strengthening of near-surface winds with a continental impact on dust emission. The present study shows the first long-term climatology of dust emission associated with Harmattan surges over North Africa. Using a newly-developed automated identification, Harmattan surges are statistically analysed in 32 years of ERA-Interim re-analysis from the European Centre for Medium-Range Weather Forecasts. The results show 34 events per year in the annual mean. Spring is herein the most active season with the largest mean number and duration of Harmattan surges, in contrast to summer with virtually no activity. The offline dust emission model by Tegen et al (2002) is used to calculate emissions with ERA-Interim data. Combining these results with the Harmattan surges allows a first quantitative estimate of the associated emission mass. The results highlight that a fraction of 32 % of the total emission is associated with these events, annually and spatially averaged across North Africa. This amount exceeds the annual mean contribution of nocturnal low-level jets to dust emission, which is known as one of the most important drivers for North

  19. LLNL Middle East and North Africa and Former Soviet Union Research Database

    SciTech Connect

    O'Boyle, J.L.; Ruppert, S.D.; Hauk, T.F.; Dodge, D.; Firpo, M.

    2000-07-14

    The Lawrence Livermore National Laboratory (LLNL) Ground-Based Nuclear Explosion Monitoring (GNEM) R and D program has made significant progress populating a comprehensive Seismic Research knowledge Base (SRKB) and deriving calibration parameters for the Middle East and North Africa (ME/NA) and Former Soviet Union (FSU) regions. The LLNL SRKB provides not only a coherent framework in which to store and organize very large volumes of collected seismic waveforms, associated event parameter information, and spatial contextual data, but also provides an efficient data processing/research environment for deriving location and discrimination correction surfaces. The SRKB is a flexible and extensible framework consisting of a relational database (RDB), Geographical Information System (GIS), and associated product/data visualization and data management tools. This SRKB framework is designed to accommodate large volumes of data (over 2 million waveforms from 20,000 events) in diverse formats from many sources in addition to maintaining detailed quality control and metadata. Using the SRKB framework, they are combining travel-time observations, event characterization studies, and regional tectonic models to assemble a library of ground truth information and phenomenology correction surfaces required for support of the ME/NA and FSU regionalization program. Corrections and parameters distilled from the LLNL SRKB provide needed contributions to the DOE Knowledge Base (DOE KB) for the ME/NA and FSU regions and will help improve monitoring for underground nuclear testing. The LLNL research products will facilitate calibration of IMS stations (primary and auxiliary), their surrogates (if not yet installed) and selected gamma stations necessary to complete the above tasks in the ME/NA and FSU regions. They present expanded lookup tables for critical station parameter information (including location and response) and a new integrated and reconciled event catalog dataset including

  20. The transpressive tectonics and large earthquake distribution along the plate boundary in North Africa

    NASA Astrophysics Data System (ADS)

    Meghraoui, Mustapha; Pondrelli, Silvia

    2010-05-01

    The Tell Atlas and Rif Mountains of northern Africa have been the site of several large and moderate seismic events in the last decades. However, the thrust and fold system of NW Algeria experienced the largest earthquakes in the last centuries along the Africa-Eurasia plate boundary. This shallow seismic activity was very often associated with surface faulting and deformation as for the Mw 7.3 El Asnam (10/10/1980) and the Mw 6.8 Zemmouri-Boumerdes (21/05/2003) earthquakes. We study the active tectonics along the plate boundary in North Africa from the seismicity database, individual large and moderate earthquakes, the seismic moment tensor summation, the geodetic measurements (GPS and InSAR) and the structural and kinematic of active faults. Neotectonic structures and significant seismicity (Mw>5) indicate that coeval east-west trending right-lateral faulting and NE-SW thrust-related folding result from the oblique convergence at the plate boundary. A simple modeling of block tectonics suggests that transpression and block rotation govern the mechanics of the Africa - Eurasia plate boundary in the Tell Atlas and Rif Mountains. The tectonic restraining bend of NW Algeria combined with the ~ 5 mm/yr convergence between Africa and Eurasia justify the large seismic activity on the thrust and fold system of the Tell Atlas and the relatively passive active deformation along the adjacent sections of the plate boundary.

  1. Summer in Mars' North Polar Region

    NASA Technical Reports Server (NTRS)

    2003-01-01

    Observations by NASA's 2001 Mars Odyssey spacecraft show a summertime view of the north polar region of Mars in intermediate-energy, or epithermal, neutrons. The map is based on data acquired by the high-energy neutron detector, one of the instruments in Odyssey's gamma-ray spectrometer suite. Soil enriched by hydrogen is indicated by the purple and deep blue colors on the map, which show a low intensity of epithermal neutrons. Progressively smaller amounts of hydrogen are shown in the colors light blue, green, yellow and red. The hydrogen is believed to be in the form of water ice. In some areas, the abundance of water ice is estimated to be up to 90 percent by volume. A shaded-relief rendition of topography is superimposed on this map for geographic reference.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. Investigators at Arizona State University in Tempe, the University of Arizona in Tucson, and NASA's Johnson Space Center, Houston, operate the science instruments. The gamma-ray spectrometer was provided by the University of Arizona in collaboration with the Russian Aviation and Space Agency and Institute for Space Research (IKI), which provided the high-energy neutron detector, and the Los Alamos National Laboratory, New Mexico, which provided the neutron spectrometer. Lockheed Martin Astronautics, Denver, is the prime contractor for the project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  2. Winter in Mars' North Polar Region

    NASA Technical Reports Server (NTRS)

    2003-01-01

    Observations by NASA's 2001 Mars Odyssey spacecraft show a wintertime view of the north polar region of Mars in intermediate-energy, or epithermal, neutrons. The map is based on data acquired by the high-energy neutron detector, one of the instruments in Odyssey's gamma-ray spectrometer suite. Soil enriched by hydrogen is indicated by the purple and deep blue colors on the map, which show a low intensity of epithermal neutrons. Progressively smaller amounts of hydrogen are shown in the colors light blue, green, yellow and red. The hydrogen is believed to be in the form of water ice. Much of the hydrogen is hidden at this time beneath a layer of carbon dioxide frost (dry ice). A shaded-relief rendition of topography is superimposed on this map for geographic reference.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. Investigators at Arizona State University in Tempe, the University of Arizona in Tucson, and NASA's Johnson Space Center, Houston, operate the science instruments. The gamma-ray spectrometer was provided by the University of Arizona in collaboration with the Russian Aviation and Space Agency and Institute for Space Research (IKI), which provided the high-energy neutron detector, and the Los Alamos National Laboratory, New Mexico, which provided the neutron spectrometer. Lockheed Martin Astronautics, Denver, is the prime contractor for the project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  3. Seismicity in Central North Africa at low magnitudes: A first look at the TAM event detected data base

    SciTech Connect

    Harben, P.E.,

    1997-01-01

    Teleseismic observations of seismicity in the central North Africa region show that the region is aseismic. This is true for earthquakes with a body wave magnitude greater than about 4 or so. For earthquakes with body wave magnitudes substantially below about 4, the teleseismic observations of seismicity in the central Sahara are incomplete since smaller earthquakes would probably not be detected and located by the current teleseismic monitoring networks. Only one known open seismic station has been operating in the central Sahara. This is the Tamanrasset (TAM) seismic station in southern Algeria. A simple analysis of data records from this station can be used to determine if the central Sahara is also relatively aseismic at magnitudes substantially below 4. That is the primary purpose of this study.

  4. Oil and gas developments in North Africa in 1981

    SciTech Connect

    Nicod, M.A.

    1982-11-01

    In the 6 countries covered by this paper, valid petroleum rights at the end of 1981 amounted to 2,024,414 km/sup 2/ or 7% more than at the end of 1980. As far as the rightholding situation is concerned, the main event was the abandonment by Esso of all its rights in Libya. Information on exploration activity remains scarce, but it is estimated that seismic activity increased by 35%. Large air-magnetometry surveys were carried out in Sudan and Egypt. Exploration drilling activity continued to increase, with 169 wells completed versus 115 in 1980. This effort led to 67 oil and gas discoveries, a success rate of about 40% compared with 35% in 1980. All these discoveries were made in established producing provinces. Highly successful results were obtained in the Gulf of Suez with 1 gas and 19 oil discoveries compared with 4 discoveries in 1980. Good success was also obtained by ONAREP, the new Moroccan state company, with 5 gas discoveries out of 11 wells spudded during the year. Chevron continued to find oil in the interior basins of Sudan, and expects commercial production in 1984 from the Unity field, which has reserves estimated at 400 million bbl of oil. Oil production markedly decreased by about 23%, with an average of 2,820,000 BOPD in 1981. Oil output decreased in all the North African countries except Egypt, where it increased 8%. Utilized natural gas production can be estimated at about 2300 MMCFGD. Sonatrach published official figures for gross gas production in 1981 which amounted to 4420 MMCFGD, of which about 2000 MMCFGD were collected and utilized.

  5. Regional variation in travel-related illness acquired in Africa, March 1997-May 2011.

    PubMed

    Mendelson, Marc; Han, Pauline V; Vincent, Peter; von Sonnenburg, Frank; Cramer, Jakob P; Loutan, Louis; Kain, Kevin C; Parola, Philippe; Hagmann, Stefan; Gkrania-Klotsas, Effrossyni; Sotir, Mark; Schlagenhauf, Patricia

    2014-04-01

    To understand geographic variation in travel-related illness acquired in distinct African regions, we used the GeoSentinel Surveillance Network database to analyze records for 16,893 ill travelers returning from Africa over a 14-year period. Travelers to northern Africa most commonly reported gastrointestinal illnesses and dog bites. Febrile illnesses were more common in travelers returning from sub-Saharan countries. Eleven travelers died, 9 of malaria; these deaths occurred mainly among male business travelers to sub-Saharan Africa. The profile of illness varied substantially by region: malaria predominated in travelers returning from Central and Western Africa; schistosomiasis, strongyloidiasis, and dengue from Eastern and Western Africa; and loaisis from Central Africa. There were few reports of vaccine-preventable infections, HIV infection, and tuberculosis. Geographic profiling of illness acquired during travel to Africa guides targeted pretravel advice, expedites diagnosis in ill returning travelers, and may influence destination choices in tourism. PMID:24655358

  6. Regional Variation in Travel-related Illness acquired in Africa, March 1997–May 2011

    PubMed Central

    Han, Pauline V.; Vincent, Peter; von Sonnenburg, Frank; Cramer, Jakob P.; Loutan, Louis; Kain, Kevin C.; Parola, Philippe; Hagmann, Stefan; Gkrania-Klotsas, Effrossyni; Sotir, Mark; Schlagenhauf, Patricia

    2014-01-01

    To understand geographic variation in travel-related illness acquired in distinct African regions, we used the GeoSentinel Surveillance Network database to analyze records for 16,893 ill travelers returning from Africa over a 14-year period. Travelers to northern Africa most commonly reported gastrointestinal illnesses and dog bites. Febrile illnesses were more common in travelers returning from sub-Saharan countries. Eleven travelers died, 9 of malaria; these deaths occurred mainly among male business travelers to sub-Saharan Africa. The profile of illness varied substantially by region: malaria predominated in travelers returning from Central and Western Africa; schistosomiasis, strongyloidiasis, and dengue from Eastern and Western Africa; and loaisis from Central Africa. There were few reports of vaccine-preventable infections, HIV infection, and tuberculosis. Geographic profiling of illness acquired during travel to Africa guides targeted pretravel advice, expedites diagnosis in ill returning travelers, and may influence destination choices in tourism. PMID:24655358

  7. Regional Model Nesting Within GFS Daily Forecasts Over West Africa

    NASA Technical Reports Server (NTRS)

    Druyan, Leonard M.; Fulakeza, Matthew; Lonergan, Patrick; Worrell, Ruben

    2010-01-01

    The study uses the RM3, the regional climate model at the Center for Climate Systems Research of Columbia University and the NASA/Goddard Institute for Space Studies (CCSR/GISS). The paper evaluates 30 48-hour RM3 weather forecasts over West Africa during September 2006 made on a 0.5 grid nested within 1 Global Forecast System (GFS) global forecasts. September 2006 was the Special Observing Period #3 of the African Monsoon Multidisciplinary Analysis (AMMA). Archived GFS initial conditions and lateral boundary conditions for the simulations from the US National Weather Service, National Oceanographic and Atmospheric Administration were interpolated four times daily. Results for precipitation forecasts are validated against Tropical Rainfall Measurement Mission (TRMM) satellite estimates and data from the Famine Early Warning System (FEWS), which includes rain gauge measurements, and forecasts of circulation are compared to reanalysis 2. Performance statistics for the precipitation forecasts include bias, root-mean-square errors and spatial correlation coefficients. The nested regional model forecasts are compared to GFS forecasts to gauge whether nesting provides additional realistic information. They are also compared to RM3 simulations driven by reanalysis 2, representing high potential skill forecasts, to gauge the sensitivity of results to lateral boundary conditions. Nested RM3/GFS forecasts generate excessive moisture advection toward West Africa, which in turn causes prodigious amounts of model precipitation. This problem is corrected by empirical adjustments in the preparation of lateral boundary conditions and initial conditions. The resulting modified simulations improve on the GFS precipitation forecasts, achieving time-space correlations with TRMM of 0.77 on the first day and 0.63 on the second day. One realtime RM3/GFS precipitation forecast made at and posted by the African Centre of Meteorological Application for Development (ACMAD) in Niamey, Niger

  8. A Regional Model Study of Synoptic Features Over West Africa

    NASA Technical Reports Server (NTRS)

    Druyan, Leonard M.; Fulakeza, Matthew; Lonergan, Patrick; Saloum, Mahaman; Hansen, James E. (Technical Monitor)

    2001-01-01

    Synoptic weather features over West Africa were studied in simulations by the regional simulation model (RM) at the NASA/Goddard Institute for Space Studies. These pioneering simulations represent the beginning of an effort to adapt regional models for weather and climate prediction over West Africa. The RM uses a cartesian grid with 50 km horizontal resolution and fifteen vertical levels. An ensemble of four simulations was forced with lateral boundary conditions from ECMWF global analyses for the period 8-22 August 1988. The simulated mid-tropospheric circulation includes the skillful development and movement of several African wave disturbances. Wavelet analysis of mid-tropospheric winds detected a dominant periodicity of about 4 days and a secondary periodicity of 5-8 days. Spatial distributions of RM precipitation and precipitation time series were validated against daily rain gauge measurements and ISCCP satellite infrared cloud imagery. The time-space distribution of simulated precipitation was made more realistic by combining the ECMWR initial conditions with a 24-hr spin-up of the moisture field and also by damping high frequency gravity waves by dynamic initialization. Model precipitation "forecasts" over the Central Sahel were correlated with observations for about three days, but reinitializing with observed data on day 5 resulted in a dramatic improvement in the precipitation validation over the remaining 9 days. Results imply that information via the lateral boundary conditions is not always sufficient to minimize departures between simulated and actual precipitation patterns for more than several days. In addition, there was some evidence that the new initialization may increase the simulations' sensitivity to the quality of lateral boundary conditions.

  9. The Epidemiology and Geographic Distribution of Relapsing Fever Borreliosis in West and North Africa, with a Review of the Ornithodoros erraticus Complex (Acari: Ixodida)

    PubMed Central

    Trape, Jean-François; Diatta, Georges; Arnathau, Céline; Bitam, Idir; Sarih, M’hammed; Belghyti, Driss; Bouattour, Ali; Elguero, Eric; Vial, Laurence; Mané, Youssouph; Baldé, Cellou; Pugnolle, Franck; Chauvancy, Gilles; Mahé, Gil; Granjon, Laurent; Duplantier, Jean-Marc

    2013-01-01

    Background Relapsing fever is the most frequent bacterial disease in Africa. Four main vector / pathogen complexes are classically recognized, with the louse Pediculus humanus acting as vector for B. recurrentis and the soft ticks Ornithodoros sonrai, O. erraticus and O. moubata acting as vectors for Borrelia crocidurae, B. hispanica and B. duttonii, respectively. Our aim was to investigate the epidemiology of the disease in West, North and Central Africa. Methods And Findings From 2002 to 2012, we conducted field surveys in 17 African countries and in Spain. We investigated the occurrence of Ornithodoros ticks in rodent burrows in 282 study sites. We collected 1,629 small mammals that may act as reservoir for Borrelia infections. Using molecular methods we studied genetic diversity among Ornithodoros ticks and Borrelia infections in ticks and small mammals. Of 9,870 burrows investigated, 1,196 (12.1%) were inhabited by Ornithodoros ticks. In West Africa, the southern and eastern limits of the vectors and Borrelia infections in ticks and small mammals were 13°N and 01°E, respectively. Molecular studies revealed the occurrence of nine different Ornithodoros species, including five species new for science, with six of them harboring Borrelia infections. Only B. crocidurae was found in West Africa and three Borrelia species were identified in North Africa: B. crocidurae, B. hispanica, and B. merionesi. Conclusions Borrelia Spirochetes responsible for relapsing fever in humans are highly prevalent both in Ornithodoros ticks and small mammals in North and West Africa but Ornithodoros ticks seem absent south of 13°N and small mammals are not infected in these regions. The number of Ornithodoros species acting as vector of relapsing fever is much higher than previously known. PMID:24223812

  10. A regional approach to water shortage problems in the Sahel region of Africa

    SciTech Connect

    Isiorho, S.A.

    1995-03-01

    The Sahel region of Africa has repeatedly experienced drought periods, such as those highlighted during the early to mid-eighties. Water, an essential of life, is a scarce commodity in the region. Lake Chad is the major source of water for approximately ten million people across four nations. For proper management of water resources in this persistently drought prone region, the regional hydrology must be understood. Remote sensing, geophysical, and geochemical techniques are currently being used in an attempt to understand the hydrology of the region. Preliminary results indicate that lineament trace analysis from remote sensing can be correlated with faults/fractures of the region, with important implications for its hydrology. Field data indicate groundwater recharge from the lake to the southwest of the Chad Basin. Because of the low annual rainfall (less than 30 cm), a high rate of evaporation (230 cm/yr) and clay-rich surface materials (topsoil) of the region, Lake Chad appears to be its main source of water, either as surface or groundwater, as indicated by preliminary isotopic data. Understanding the hydrology of the region is imperative for the proper management of water resources in this drought-prone part of Africa. The governments of the Sahel need to approach the water shortage problem from a regional point of view.

  11. Evolution around the Red Sea: Systematics and biogeography of the agamid genus Pseudotrapelus (Squamata: Agamidae) from North Africa and Arabia.

    PubMed

    Tamar, Karin; Scholz, Sebastian; Crochet, Pierre-André; Geniez, Philippe; Meiri, Shai; Schmitz, Andreas; Wilms, Thomas; Carranza, Salvador

    2016-04-01

    Since the Oligocene, regions adjacent to the Red Sea have experienced major environmental changes, from tectonic movements and continuous geological activity to shifting climatic conditions. The effect of these events on the distribution and diversity of the regional biota is still poorly understood. Agamid members of the genus Pseudotrapelus are diurnal, arid-adapted lizards distributed around the Red Sea from north-eastern Africa, across the mountains and rocky plateaus of the Sinai and Arabian Peninsulas northwards to Syria. Despite recent taxonomic work and the interest in the group as a model for studying biogeographic and diversity patterns of the arid areas of North Africa and Arabia, its taxonomy is poorly understood and a comprehensive phylogeny is still lacking. In this study, we analyzed 92 Pseudotrapelus specimens from across the entire distribution range of the genus. We included all known species and subspecies, and sequenced them for mitochondrial (16S, ND4 and tRNAs) and nuclear (MC1R, c-mos) markers. This enabled us to obtain the first time-calibrated molecular phylogeny of the genus, using gene trees, species trees and coalescent-based methods for species delimitation. Our results revealed Pseudotrapelus as a monophyletic genus comprised of two major clades and six independently evolving lineages. These lineages correspond to the five currently recognized species and a sixth lineage relating to the synonymized P. neumanni. The subspecific validity of P. sinaitus werneri needs further assessment as it does not form a distinct cluster relative to P. s. sinaitus. The onset of Pseudotrapelus diversification is estimated to have occurred in Arabia during the late Miocene. Radiation has likely resulted from vicariance and dispersal events due to the continued geological instability, sea level fluctuations and climatic changes within the region. PMID:26772670

  12. Identifying important breast cancer control strategies in Asia, Latin America and the Middle East/North Africa

    PubMed Central

    2011-01-01

    Background Breast cancer is the most frequent cause of cancer death in women worldwide, but global disparities in breast cancer control persist, due to a lack of a comprehensive breast cancer control strategy in many countries. Objectives To identify and compare the need for breast cancer control strategies in Asia, Latin America and the Middle East/North Africa and to develop a common framework to guide the development of national breast cancer control strategies. Methods Data were derived from open-ended, semi-structured interviews conducted in 2007 with 221 clinicians, policy makers, and patient advocates; stratified across Asia (n = 97), Latin America (n = 46), the Middle East/North Africa (ME/NA) (n = 39) and Australia and Canada (n = 39). Respondents were identified using purposive and snowballing sampling. Interpretation of the data utilized interpretive phenomenological analysis where transcripts and field notes were coded and analyzed and common themes were identified. Analysis of regional variation was conducted based on the frequency of discussion and the writing of the manuscript followed the RATS guidelines. Results Analysis revealed four major themes that form the foundation for developing national breast cancer control strategies: 1) building capacity; 2) developing evidence; 3) removing barriers; and 4) promoting advocacy - each specified across five sub-ordinate dimensions. The propensity to discuss most dimensions was similar across regions, but managing advocacy was discussed more frequently (p = 0.004) and organized advocacy was discussed less frequently (p < 0.001) in Australia and Canada. Conclusions This unique research identified common themes for the development of breast cancer control strategies, grounded in the experience of local practitioners, policy makers and advocacy leaders across diverse regions. Future research should be aimed at gathering a wider array of experiences, including those of patients. PMID:21933435

  13. Differences in Reliability of Reproductive History Recall Among Women in North Africa

    PubMed Central

    Soliman, Amr; Allen, Katharine; Lo, An-Chi; Banerjee, Mousumi; Hablas, Ahmed; Benider, Abdellatif; Benchekroun, Nadya; Samir, Salwa; Omar, Hoda G.; Merajver, Sofia; Mullan, Patricia

    2014-01-01

    Breast cancer is the most common cancer among women in North Africa. Women in this region have unique reproductive profiles. It is essential to obtain reliable information on reproductive histories to help better understand the relationship between reductive health and breast cancer. We tested the reliability of a reproductive history-based questionnaire. We interviewed 25 breast cancer patients and 25 non-cancer controls from hospitals in Morocco and Egypt about their reproductive history in colloquial Arabic. The questions included pregnancy history, breastfeeding practices, menstruation, contraceptive use and knowledge of breast screening and re-interviewed the same women after 2 weeks. Two-way paired t-test was used to compare observed mean changes in response, and the Fishers Exact test was used for small-cell data. Pearson's correlation test was used to estimate the correlation of subjects’ responses to continuous questions between the first and second interview. For categorical questions, percentage of agreement was calculated along with Cohen’s Kappa Coefficient values. Moroccan subjects showed good to excellent agreement for responses to all demographic and reproductive questions (r = 0.87 to 0.99). Egyptian subjects had excellent agreement for these questions(r = 0.87 to 0.99), except for those regarding duration of oral contraceptive pill use and reported age at menarche (r = 0.72 and 0.59, respectively). We showed highly correlated responses to most reproductive questions. Duration of contraception use and age at first pregnancy elicited slightly less than reliable responses. In Egypt, responses relating to self-reported age at menarche were less reliable than those given by Moroccan subjects. Future epidemiological studies should take these differences into account when constructing reproductive history questionnaires. PMID:25620888

  14. A crust and upper mantle model of Eurasia and North Africa for Pn travel time calculation

    SciTech Connect

    Myers, S; Begnaud, M; Ballard, S; Pasyanos, M; Phillips, W S; Ramirez, A; Antolik, M; Hutchenson, K; Dwyer, J; Rowe, C; Wagner, G

    2009-03-19

    We develop a Regional Seismic Travel Time (RSTT) model and methods to account for the first-order effect of the three-dimensional crust and upper mantle on travel times. The model parameterization is a global tessellation of nodes with a velocity profile at each node. Interpolation of the velocity profiles generates a 3-dimensional crust and laterally variable upper mantle velocity. The upper mantle velocity profile at each node is represented as a linear velocity gradient, which enables travel time computation in approximately 1 millisecond. This computational speed allows the model to be used in routine analyses in operational monitoring systems. We refine the model using a tomographic formulation that adjusts the average crustal velocity, mantle velocity at the Moho, and the mantle velocity gradient at each node. While the RSTT model is inherently global and our ultimate goal is to produce a model that provides accurate travel time predictions over the globe, our first RSTT tomography effort covers Eurasia and North Africa, where we have compiled a data set of approximately 600,000 Pn arrivals that provide path coverage over this vast area. Ten percent of the tomography data are randomly selected and set aside for testing purposes. Travel time residual variance for the validation data is reduced by 32%. Based on a geographically distributed set of validation events with epicenter accuracy of 5 km or better, epicenter error using 16 Pn arrivals is reduced by 46% from 17.3 km (ak135 model) to 9.3 km after tomography. Relative to the ak135 model, the median uncertainty ellipse area is reduced by 68% from 3070 km{sup 2} to 994 km{sup 2}, and the number of ellipses with area less than 1000 km{sup 2}, which is the area allowed for onsite inspection under the Comprehensive Nuclear Test Ban Treaty, is increased from 0% to 51%.

  15. Regional, Continental, and Global Mobility to an Emerging Economy: The Case of South Africa

    ERIC Educational Resources Information Center

    Lee, Jenny J.; Sehoole, Chika

    2015-01-01

    This study examined mobility within the understudied region of southern Africa and particularly, the factors that drive and shape educational migration toward South Africa as a regional, continental, and global destination. Based on a survey administered to international students across seven South African universities, the findings revealed…

  16. Late Quaternary hydrology in North Africa and the Near East (Hans Oeschger Medal Lecture)

    NASA Astrophysics Data System (ADS)

    Gasse, Françoise

    2010-05-01

    The present-day arid-semiarid belt from North Africa to West Asia has experienced huge hydrological changes together with a long history of human civilisations. This belt straddles the boundary between a temperate domain (winter rains linked to the mid-latitude Westerlies), and a subtropical one (rare monsoonal summer precipitation). What are the timing and direction of major hydrological changes in these two domains ? How does the transitional zone migrate through time, and why ? How did human societies respond to changes in water availability ? These questions are addressed using records illustrating both long and short-term environmental changes. At the glacial-interglacial time scale, hydrological changes broadly follow the orbitally-induced Northern Hemisphere summer insolation, but with different regional expressions. In the winter rain domain, the best-dated records come from southern Levant : stable isotope records from speleothems in Israel (120-230 ka) show a remarkable consistency with those from the Eastern Mediterranean Sea(1,2), but the prominant role of rainfall amount or of moisture source isotopic composition on inland records is still debated (1-4); lake-level reconstructions in the Lisan-Dead Sea basin during the past 70 ka demonstrate higher winter rains during the last glacial period than during the Holocene (4,5). However, a new multi-proxy lacustrine record (230 ka) from northern Levant (Yammoûneh, Lebanon) shows relatively wet environments during interglacial periods(6,7), suggesting temporal changes in the NS climatic gradients over the Levantine region. Extratropical rainfalls apparently remained predominant over northern Sahara, with a major period of aquifer recharge during the Late Pleistocene(8). Conversely, south of about 25-22° N, the subtropical deserts experienced pluvial periods during interglacials, including the remarkable early-Mid Holocene wetting of the Saharan heart(8). Older pluvial periods, precisely dated in speleothems

  17. Sustainable Electricity and Water for Europe, Middle East and North Africa

    NASA Astrophysics Data System (ADS)

    Müller-Steinhagen, H.; Trieb, F.

    2009-04-01

    Sufficient supply of energy and water are among the key requirements for a sustainable development of nations. Both depend strongly on energy carriers such as oil, gas, coal and uranium which have limited availability and a negative impact on the environment during their use. Within the framework of a series of detailed studies, conventional and renewable energy sources available for electricity production and desalination in Europe, North Africa and the Middle East (EU-MENA) have been analysed. Scenarios have been developed for a sustainable electricity supply based on increased plant and user efficiency, and an accelerated introduction of renewable energy sources. Even if all potential exclusion criteria are applied and only those technologies are considered which will become economically competitive within the next decades, a potential has been identified which exceeds the present electricity demand by orders of magnitude. Solar energy is, in this context, the by far largest resource which will most economically be exploited in centralised solar thermal power plants. In combination with heat storage, these power plants can provide bulk and peak electricity, and can be combined with thermal or reverse osmosis desalination plants. At present, solar thermal power plants with a total capacity exceeding 10 GW are in operation or under construction in Abu Dhabi, Algeria, Egypt, Iran, Israel, Italy, Morocco, Spain and the USA. Ultimately, the increasing electricity demand of EU-MENA can only be secured in conjunction with the required climate and resource protection targets, if all renewable energy sources are exploited where appropriate, and conversion and user efficiency are increased. To utilise the enormous energy resources of the Mediterranean countries, high voltage direct current power lines will have to be built, linking the most abundant and economic resources with the load centres in the North. With electricity losses below 10% over a distance of 3000 km

  18. Depositional sequence evolution, Paleozoic and early Mesozoic of the central Saharan platform, North Africa

    SciTech Connect

    Sprague, A.R.G. )

    1991-08-01

    Over 30 depositional sequences have been identified in the Paleozoic and lower Mesozoic of the Ghadames basin of eastern Algeria, southern Tunisia, and western Libya. Well logs and lithologic information from more than 500 wells were used to correlate the 30 sequences throughout the basin (total area more than 1 million km{sup 2}). Based on systematic change in the log response of strata in successively younger sequences, five groups of sequences with distinctive characteristics have been identified: Cambro-Ordivician, Upper Silurian-Middle Devonian, Upper Devonian, Carboniferous, and Middle Triassic-Middle Jurassic. Each sequence group is terminated by a major, tectonically enhanced sequence boundary that is immediately overlain (except for the Carboniferous) by a shale-prone interval deposited in response to basin-wide flooding. The four Paleozoic sequence groups were deposited on the Saharan platform, a north facing, clastic-dominated shelf that covered most of North Africa during the Paleozoic. The sequence boundary at the top of the Carboniferous sequence group is one of several Permian-Carboniferous angular unconformities in North Africa related to the Hercynian orogeny. The youngest sequence group (Middle Triassic to Middle Jurassic) is a clastic-evaporite package that onlaps southward onto the top of Paleozoic sequence boundary. The progressive changes from the Cambrian to the Jurassic, in the nature of the Ghadames basin sequences is a reflection of the interplay between basin morphology and tectonics, vegetation, eustasy, climate, and sediment supply.

  19. The development of the continental margin of eastern North America—conjugate continental margin to West Africa

    NASA Astrophysics Data System (ADS)

    Dillon, William P.; Schlee, John S.; Klitgord, Kim D.

    The continental margin of eastern North America was initiated when West Africa and North America were rifted apart in Triassic-Early Jurassic time. Cooling of the crust and its thinning by rifting and extension caused subsidence. Variation in amounts of subsidence led to formation of five basins. These are listed from south to north. (1) The Blake Plateau Basin, the southernmost, is the widest basin and the one in which the rift-stage basement took longest to form. Carbonate platform deposition was active and persisted until the end of Early Cretaceous. In Late Cretaceous, deposition slowed while subsidence persisted, so a deep water platform was formed. Since the Paleocene the region has undergone erosion. (2) The Carolina Trough is narrow and has relatively thin basement, on the basis of gravity modeling. The two basins with thin basement, the Carolina Trough and Scotian Basin, also show many salt diapirs indicating considerable deposition of salt during their early evolution. In the Carolina Trough, subsidence of a large block of strata above the flowing salt has resulted in a major, active normal fault on the landward side of the basin. (3) The Baltimore Canyon Trough has an extremely thick sedimentary section; synrift and postrift sediments exceed 18 km in thickness. A Jurassic reef is well developed on the basin's seaward side, but post-Jurassic deposition was mainly non-carbonate. In general the conversion from carbonate to terrigenous deposition, characteristics of North American Basins, occurred progressively earlier toward the north. (4) The Georges Bank Basin has a complicated deep structure of sub-basins filled with thick synrift deposits. This may have resulted from some shearing that occurred at this offset of the continental margin. Postrift sediments apparently are thin compared to other basins—only about 8 km. (5) The Scotian Basin, off Canada, contains Jurassic carbonate rocks, sandstone, shale and coal covered by deltaic deposits and Upper

  20. The development of the continental margin of eastern North America-conjugate continental margin to West Africa

    USGS Publications Warehouse

    Dillon, William P.; Schlee, J.S.; Klitgord, Kim D.

    1988-01-01

    The continental margin of eastern North America was initiated when West Africa and North America were rifted apart in Triassic-Early Jurassic time. Cooling of the crust and its thinning by rifting and extension caused subsidence. Variation in amounts of subsidence led to formation of five basins. These are listed from south to north. (1) The Blake Plateau Basin, the southernmost, is the widest basin and the one in which the rift-stage basement took longest to form. Carbonate platform deposition was active and persisted until the end of Early Cretaceous. In Late Cretaceous, deposition slowed while subsidence persisted, so a deep water platform was formed. Since the Paleocene the region has undergone erosion. (2) The Carolina Trough is narrow and has relatively thin basement, on the basis of gravity modeling. The two basins with thin basement, the Carolina Trough and Scotian Basin, also show many salt diapirs indicating considerable deposition of salt during their early evolution. In the Carolina Trough, subsidence of a large block of strata above the flowing salt has resulted in a major, active normal fault on the landward side of the basin. (3) The Baltimore Canyon Trough has an extremely thick sedimentary section; synrift and postrift sediments exceed 18 km in thickness. A Jurassic reef is well developed on the basin's seaward side, but post-Jurassic deposition was mainly non-carbonate. In general the conversion from carbonate to terrigenous deposition, characteristics of North American Basins, occurred progressively earlier toward the north. (4) The Georges Bank Basin has a complicated deep structure of sub-basins filled with thick synrift deposits. This may have resulted from some shearing that occurred at this offset of the continental margin. Postrift sediments apparently are thin compared to other basins-only about 8 km. (5) The Scotian Basin, off Canada, contains Jurassic carbonate rocks, sandstone, shale and coal covered by deltaic deposits and Upper

  1. Characterizing the Effects of Irrigation in the Middle East and North Africa Using Remotely Sensed Vegetation and Water Cycle Observations

    NASA Technical Reports Server (NTRS)

    Bolten, John; Ozdogan, Mutlu; Beaudoing, Hiroko; Rodell, Matthew

    2012-01-01

    A majority of the countries in the Middle East and North Africa (MENA) region suffer from water scarcity due in part to widespread rainfall deficits, unprecedented levels of water demand, and the inefficient use of renewable freshwater resources. Since a majority of the water withdrawal in the MENA is used for irrigation, there is a desperate need for improved understanding of irrigation practices and agricultural water use in the region. Here, satellite-derived irrigation maps and crop-type agricultural data are applied to the Land Data Assimilation System for the MENA region (MENA LDAS), designed to provide regional, gridded fields of hydrological states and fluxes relevant for water resources assessments. Within MENA-LDAS, the Catchment Land Surface Model (CLSM) simulates the location, timing, and amount of water applied through agricultural irrigation practices over the region from 2002-2012. In addition to simulating the irrigation impact on evapotranspiration, soil moisture, and runoff, we also investigate regional changes in terrestrial water storage (TWS) observed from the Gravity Recovery and Climate Experiment (GRACE) and simulated by CLSM.

  2. Honor killings in the Middle East and North Africa: a systematic review of the literature.

    PubMed

    Kulczycki, Andrzej; Windle, Sarah

    2011-11-01

    A systematic review of the research literature on honor killings in the Middle East and North Africa (MENA) indicates a paucity of studies relative to the presumed magnitude of the problem. Forty articles were reviewed and critically appraised, of which only 9 contained primary data and 11 presented original secondary analyses. Despite a recent increase in published studies, persistent methodological limitations restrict the generalizability of findings. Most studies focus on legal aspects, determinants, and characteristics of victims and perpetrators. Victims are mostly young females murdered by their male kin. Unambiguous evidence of a decline in tolerance of honor killings remains elusive. PMID:22312039

  3. Fluoride in groundwater in selected villages in Eritrea (North East Africa).

    PubMed

    Srikanth, R; Viswanatham, K S; Kahsai, Fikremariam; Fisahatsion, Abraham; Asmellash, Micheal

    2002-04-01

    A study was undertaken to estimate fluoride content in the groundwater in certain parts of rural Eritrea. North-East Africa, along the River Anseba. Standard procedure was adopted for fluoride detection. Results indicate elevated concentration of fluoride in groundwater. The highest concentration was found to be 3.73 mg L(-1), well above the safety level for consumption. Geological basis for the high concentration of high fluoride has been established; it is presumed to be the pegmatite intrusion hosted by a granitic batholith. Extensive dental fluorosis has been observed in the population exposed to drinking water of high fluoride content. PMID:12002285

  4. A Climatology of Dust-Emission Events over North Africa Based on 27 Years of Surface Observations

    NASA Astrophysics Data System (ADS)

    Cowie, S.; Knippertz, P.; Schepanski, K.

    2012-04-01

    The huge quantity of mineral dust emitted annually from North Africa makes this area crucial to the global dust cycle. Once in the atmosphere, dust aerosols have a significant impact on the global radiation budget, clouds, the carbon cycle and can even act as a fertilizer to rain forests in South America. Current model estimates of dust production from North Africa are uncertain. At the heart of this problem is insufficient understanding of key dust emitting processes such as haboobs (cold pools generated through evaporation of convective precipitation), low-level jets (LLJs), and dry convection (dust devils and dust plumes). Scarce observations in this region, in particular in the Sahara, make model evaluation difficult. This work uses long-term surface observations from the MIDAS data set (~120 stations in the arid part of North Africa) to explore the diurnal, seasonal, decadal and geographical variations in dust emission events and their associated wind thresholds. The threshold values are determined from probability density functions of observed 10-minute anemomenter wind speeds. Emission events are defined using the present weather codes (WW) of SYNOP reports. These codes represent events of smaller intensity such as "Dust or sand raised by wind" to severe dust storms. During the 27-year study period (1984-2011) stations are required to have a minimum of 1000 dust observations to be included in the analysis. Dust emission frequency (DEF) is calculated for different time intervals (e.g. monthly, 3-hourly) taking into account the different number of measurements available at each station. North of 25°N a maximum during March-May is evident and relatively consistent over the whole North African region. Wind-speed thresholds for dust emission north of 25°N are higher than south of 25°N in the Sahel, where station-to-station variability is larger, and enhanced DEF activity during February-March is observed. The variability in this region is closely linked to the

  5. Grid search modeling of receiver functions: Implications for crustal structure in the Middle East and North Africa

    SciTech Connect

    Sandvol, E.; Seber, D.; Calvert, A.; Barazangi, M.

    1998-11-01

    A grid search is used to estimate average crustal thickness and shear wave velocity structure beneath 12 three-component broadband seismic stations in the Middle East, North Africa, and nearby regions. The crustal thickness in these regions is found to vary from a minimum of 8.0{plus_minus}1.5&hthinsp;km in East Africa (Afar) region to possibly a maximum of 64{plus_minus}4.8&hthinsp;km in the lesser Caucasus. Stations located within the stable African platform indicate a crustal thickness of about 40 km. Teleseismic three-component waveform data produced by 165 earthquakes are used to create receiver function stacks for each station. Using a grid search, we have solved for the optimal and most simple shear velocity models beneath all 12 stations. Unlike other techniques (linearized least squares or forward modeling), the grid search methodology guarantees that we solve for the global minimum within our defined model parameter space. Using the grid search, we also qualitatively estimate the least number of layers required to model the observed receiver functions{close_quote} major seismic phases (e.g., PS{sub Moho}). A jackknife error estimation method is used to test the stability of our receiver function inversions for all 12 stations in the region that had recorded a sufficient number of high-quality broadband teleseismic waveforms. Five of the 12 estimates of crustal thicknesses are consistent with what is known of crustal structure from prior geophysical work. Furthermore, the remaining seven estimates of crustal structure are in regions for which previously there were few or no data about crustal thickness. {copyright} 1998 American Geophysical Union

  6. A European Mitochondrial Haplotype Identified in Ancient Phoenician Remains from Carthage, North Africa.

    PubMed

    Matisoo-Smith, Elizabeth A; Gosling, Anna L; Boocock, James; Kardailsky, Olga; Kurumilian, Yara; Roudesli-Chebbi, Sihem; Badre, Leila; Morel, Jean-Paul; Sebaï, Leïla Ladjimi; Zalloua, Pierre A

    2016-01-01

    While Phoenician culture and trade networks had a significant impact on Western civilizations, we know little about the Phoenicians themselves. In 1994, a Punic burial crypt was discovered on Byrsa Hill, near the entry to the National Museum of Carthage in Tunisia. Inside this crypt were the remains of a young man along with a range of burial goods, all dating to the late 6th century BCE. Here we describe the complete mitochondrial genome recovered from the Young Man of Byrsa and identify that he carried a rare European haplogroup, likely linking his maternal ancestry to Phoenician influenced locations somewhere on the North Mediterranean coast, the islands of the Mediterranean or the Iberian Peninsula. This result not only provides the first direct ancient DNA evidence of a Phoenician individual but the earliest evidence of a European mitochondrial haplogroup, U5b2c1, in North Africa. PMID:27224451

  7. A European Mitochondrial Haplotype Identified in Ancient Phoenician Remains from Carthage, North Africa

    PubMed Central

    Matisoo-Smith, Elizabeth A.; Gosling, Anna L.; Boocock, James; Kardailsky, Olga; Kurumilian, Yara; Roudesli-Chebbi, Sihem; Badre, Leila; Morel, Jean-Paul; Sebaï, Leïla Ladjimi; Zalloua, Pierre A.

    2016-01-01

    While Phoenician culture and trade networks had a significant impact on Western civilizations, we know little about the Phoenicians themselves. In 1994, a Punic burial crypt was discovered on Byrsa Hill, near the entry to the National Museum of Carthage in Tunisia. Inside this crypt were the remains of a young man along with a range of burial goods, all dating to the late 6th century BCE. Here we describe the complete mitochondrial genome recovered from the Young Man of Byrsa and identify that he carried a rare European haplogroup, likely linking his maternal ancestry to Phoenician influenced locations somewhere on the North Mediterranean coast, the islands of the Mediterranean or the Iberian Peninsula. This result not only provides the first direct ancient DNA evidence of a Phoenician individual but the earliest evidence of a European mitochondrial haplogroup, U5b2c1, in North Africa. PMID:27224451

  8. Detecting vegetation-precipitation feedbacks in mid-Holocene North Africa from two climate models

    SciTech Connect

    Wang, Yi; Notaro, Michael; Liu, Zhengyu; Gallimore, Robert; Levis, Samuel; Kutzbach, John E.

    2008-03-31

    Using two climate-vegetation model simulations from the Fast Ocean Atmosphere Model (FOAM) and the Community Climate System Model (CCSM, version 2), we investigate vegetation-precipitation feedbacks across North Africa during the mid-Holocene. From mid-Holocene snapshot runs of FOAM and CCSM2, we detect a negative feedback at the annual timescale with our statistical analysis. Using the Monte- Carlo bootstrap method, the annual negative feedback is further confirmed to be significant in both simulations. Additional analysis shows that this negative interaction is partially caused by the competition between evaporation and transpiration in North African grasslands. Furthermore, we find the feedbacks decrease with increasing timescales, and change signs from positive to negative at increasing timescales in FOAM. The proposed mechanism for this sign switch is associated with the different persistent timescales of upper and lower soil water contents, and their interactions with vegetation and atmospheric precipitation.

  9. Analysis of Genomic Regions Associated With Coronary Artery Disease Reveals Continent-Specific Single Nucleotide Polymorphisms in North African Populations

    PubMed Central

    Zanetti, Daniela; Via, Marc; Carreras-Torres, Robert; Esteban, Esther; Chaabani, Hassen; Anaibar, Fatima; Harich, Nourdin; Habbal, Rachida; Ghalim, Noreddine; Moral, Pedro

    2016-01-01

    Background In recent years, several genomic regions have been robustly associated with coronary artery disease (CAD) in different genome-wide association studies (GWASs) conducted mainly in people of European descent. These kinds of data are lacking in African populations, even though heart diseases are a major cause of premature death and disability. Methods Here, 384 single nucleotide polymorphisms (SNPs) in the top four CAD risk regions (1p13, 1q41, 9p21, and 10q11) were genotyped in 274 case-control samples from Morocco and Tunisia, with the aim of analyzing for the first time if the associations found in European populations were transferable to North Africans. Results The results indicate that, as in Europe, these four genetic regions are also important for CAD risk in North Africa. However, the individual SNPs associated with CAD in Africa are different from those identified in Europe in most cases (1p13, 1q41, and 9p21). Moreover, the seven risk variants identified in North Africans are efficient in discriminating between cases and controls in North African populations, but not in European populations. Conclusions This study indicates a disparity in markers associated to CAD susceptibility between North Africans and Europeans that may be related to population differences in the chromosomal architecture of these risk regions. PMID:26780859

  10. Preliminary report on osteochondrosis in cattle in the north-western parts of South Africa.

    PubMed

    Prozesky, Leon; Neser, Johan; Meissner, Heinz; Botha, Kenneth; Jacobs, Lubbe; Shepstone, Craig; Viljoen, Hannes; Köster, Hinner; De Brouwer, Chris; Van Zyl, Jan; Van der Veen, Gerjan

    2016-01-01

    The north-western part of South Africa, in particular, is well known for mineral imbalances. Aphosphorosis, resulting in rickets and osteomalacia, received a lot of attention at the turn of the nineteenth century (1882-1912). This was followed in 1997 by research on Vryburg hepatosis, another area-specific mineral imbalance-related disease in young calves reared on manganese-rich soil derived from the weathering of dolomitic (carbonate) rock formations. In 1982, a totally new syndrome (osteochondrosis) manifested in, amongst others, areas in South Africa where aphosphorosis was rife. Osteochondrosis was also identified in the south-western parts of Namibia as well as southern Botswana and other areas in South Africa. Osteochondrosis has a multifactorial aetiology and this study focused on the role of minerals, particularly phosphorus, in the development of the disease. A significant improvement in the clinical signs in experimental animals and a reduction of osteochondrosis occurred on farms where animals received bioavailable trace minerals and phosphorus as part of a balanced lick. An increase in the occurrence of the disease on farms during severe drought conditions in 2012-2013 prompted researchers to investigate the possible role of chronic metabolic acidosis in the pathogenesis of the disease. PMID:27543146

  11. Community Support for Basic Education in Sub-Saharan Africa. Africa Region Human Development Working Paper Series.

    ERIC Educational Resources Information Center

    Watt, Patrick

    Currently, Africa stands out as the world's poorest and most educationally deprived region. Where communities are empowered to identify their own needs and priorities, participate in decisions about resource allocation, and hold education providers accountable for ensuring that children receive a minimum acceptable standard of education, schooling…

  12. Refugees in and out North Africa: a study of the Choucha refugee camp in Tunisia.

    PubMed

    Dourgnon, Paul; Kassar, Hassène

    2014-08-01

    In recent years, North African (NA) countries ceased to be emigration-only countries and are now on the verge of becoming immigration as well as transit countries for economic migrants and refugees. Contextual as well as structural long-term factors are driving these changes. The ongoing crises in Africa and the Middle East are prompting strong outflows of refugees, which are likely to induce NA countries to share some common public policy and public health concerns with European countries in a near future. This article highlights some aspects of these changes, from the study of the consequences of the 2011 Libyan crisis in Tunisia. It addresses individual trajectories and health concerns of refugees in and out North Africa from a study of the Choucha camp in Tunisia. The camp opened to immigrants from Libya during the 2011 crisis and accommodated the bulk of the refugees flow to Tunisia until July 2012. The study includes a monographic approach and a qualitative survey in the Choucha camp refugees. We describe the crisis history and the health response with a focus on the camp. We then address refugees' trajectories, and health needs and concerns from the interviews we collected in the camp in April 2012. PMID:25107992

  13. Mortality of children in the Transkei region of South Africa.

    PubMed

    Meel, B L

    2003-06-01

    This study attempted to unfold, perhaps for the first time, the problem of childhood mortality resulting from trauma in the Eastern Cape Province of South Africa. This study was carried out in the Umtata and Ngqeleni magisterial districts, which have a combined population of about 400,000. Most people there have very few resources and have historically relied on money repatriated by migrant workers. In the Transkei region, unemployment is at a very high level: 48.5%. Assault on children is very common in this region, and this may result in death. The aim of this study was to establish the state of deaths resulting from pediatric trauma, and to formulate recommendations that could probably help prevent or reduce these deaths. The objective was to gather epidemiologic information on the victims of pediatric trauma. The study was designed as a descriptive study, using reviews of traumatic deaths in pediatric age groups during the period January 1993 to December 1999. This study was carried out on cases that were brought to the medicolegal laboratory at Umtata General Hospital, Umtata, in the Transkei region of the Eastern Cape Province, South Africa. There were 6181 autopsies conducted from 1993 to 1999. All the medicolegal autopsies were divided into two groups: pediatric (15 years of age or younger) and adult (older than 15 years). Of the autopsies, 89.4% (n = 5587) were in the adult group, and 10.6% (n = 594) were in the pediatric group. Of the pediatric deaths, 64% (n = 383) were related to trauma. The highest numbers were in the 11- to 15-year (n = 146, 38%) and the 6- to 10-year (n = 135, 34%) age groups. Of the children who died of trauma, 112 (28%) were aged 0 to 5 years. Unintentional injuries from motor vehicle accidents were the leading cause of death (59%), whereas intentional injuries (41%) were associated with murder. Nearly a quarter (22%) of pediatric traumatic deaths were due to penetrating injuries: stab (12%) and gunshot (10%) wounds. Most of the

  14. A late Pleistocene refugium in Mediterranean North Africa? Palaeoenvironmental reconstruction from stable isotope analyses of land snail shells (Haua Fteah, Libya)

    NASA Astrophysics Data System (ADS)

    Prendergast, A. L.; Stevens, R. E.; O'Connell, T. C.; Hill, E. A.; Hunt, C. O.; Barker, G. W.

    2016-05-01

    The late Pleistocene to Holocene archaeological record of North Africa is key to understanding the emergence of anatomically modern humans into West Asia and Europe, and the broadening of subsistence strategies in the shift from hunter-gatherer to pastoral-agricultural lifeways. Some contend that these developments were modulated by major shifts in climate and environment. Evaluation of this hypothesis requires the pairing of local and regional climate records with well-dated archaeological sequences. The Haua Fteah archaeological site in the Gebel Akhdar region of Libya provides a key site to test this hypothesis as the cave contains one of the longest and most complete sequences of human occupation in North Africa as well as abundant material for palaeoenvironmental reconstruction. This study uses stable isotope analyses (δ18O and δ13C) of the terrestrial mollusc Helix melanostoma to construct a palaeoenvironmental framework for interpreting North African human-environment interactions from the Upper Palaeolithic to the Neolithic (∼30,000 to 5000 years ago). The land snail stable isotope records from Haua Fteah suggests that cool arid conditions in the cave peaked during marine isotope stage (MIS) 2. This stage was, however, only marginally drier than previous and subsequent stages and coincided with an increase in occupation density in the cave. This suggests that the Gebel Akhdar may have served as an environmental refugium from the more extreme aridity in the surrounding Sahara and arid coastal plains for Late Stone Age (LSA) populations in North Africa. Conditions became progressively wetter towards the Holocene. However, generally wetter conditions were interrupted by two arid episodes at c. 8.0 ka and 7.3 ka that appear to coincide with regional changes reflected elsewhere in the Mediterranean basin.

  15. Climatology of nocturnal low-level jets over North Africa and implications for modeling mineral dust emission

    PubMed Central

    Fiedler, S; Schepanski, K; Heinold, B; Knippertz, P; Tegen, I

    2013-01-01

    [1] This study presents the first climatology for the dust emission amount associated with Nocturnal Low-Level Jets (NLLJs) in North Africa. These wind speed maxima near the top of the nocturnal boundary layer can generate near-surface peak winds due to shear-driven turbulence in the course of the night and the NLLJ breakdown during the following morning. The associated increase in the near-surface wind speed is a driver for mineral dust emission. A new detection algorithm for NLLJs is presented and used for a statistical assessment of NLLJs in 32 years of ERA-Interim reanalysis from the European Centre for Medium-Range Weather Forecasts. NLLJs occur in 29% of the nights in the annual and spatial mean. The NLLJ climatology shows a distinct annual cycle with marked regional differences. Maxima of up to 80% NLLJ frequency are found where low-level baroclinicity and orographic channels cause favorable conditions, e.g., over the Bodélé Depression, Chad, for November–February and along the West Saharan and Mauritanian coast for April–September. Downward mixing of NLLJ momentum to the surface causes 15% of mineral dust emission in the annual and spatial mean and can be associated with up to 60% of the total dust amount in specific areas, e.g., the Bodélé Depression and south of the Hoggar-Tibesti Channel. The sharp diurnal cycle underlines the importance of using wind speed information with high temporal resolution as driving fields for dust emission models. Citation: Fiedler, S., K. Schepanski, B. Heinold, P. Knippertz, and I. Tegen (2013), Climatology of nocturnal low-level jets over North Africa and implications for modeling mineral dust emission, J. Geophys. Res. Atmos., 118, 6100-6121, doi:10.1002/jgrd.50394 PMID:25893154

  16. BETR North America: A regionally segmented multimedia contaminant fate model for North America

    SciTech Connect

    MacLeod, M.; Woodfine, D.G.; Mackay, D.; McKone, T.E.; Bennett, D.H.; Maddalena, R.L.

    2001-03-01

    We present the Berkeley-Trent North American contaminant fate model (BETR North America), a regionally segmented multimedia contaminant fate model based on the fugacity concept. The model is built on a framework that links contaminant fate models of individual regions, and is generally applicable to large, spatially heterogeneous areas. The North American environment is modeled as 24 ecological regions, within each region contaminant fate is described using a 7 compartment multimedia fugacity model including a vertically segmented atmosphere, freshwater, freshwater sediment, soil, coastal water and vegetation compartments. Inter-regional transport of contaminants in the atmosphere, freshwater and coastal water is described using a database of hydrological and meteorological data compiled with Geographical Information Systems (GIS) techniques. Steady-state and dynamic solutions to the 168 mass balance equations that make up the linked model for North America are discussed, and an illustrative case study of toxaphene transport from the southern United States to the Great Lakes Basin is presented. Regionally segmented models such as BETR North America can provide a critical link between evaluative models of long-range transport potential and contaminant concentrations observed in remote regions. The continent-scale mass balance calculated by the model provides a sound basis for evaluating long-range transport potential of organic pollutants, and formulation of continent scale management and regulatory strategies for chemicals.

  17. Population genetic structure of Plasmodium falciparum across a region of diverse endemicity in West Africa

    PubMed Central

    2012-01-01

    Background Malaria parasite population genetic structure varies among areas of differing endemicity, but this has not been systematically studied across Plasmodium falciparum populations in Africa where most infections occur. Methods Ten polymorphic P. falciparum microsatellite loci were genotyped in 268 infections from eight locations in four West African countries (Republic of Guinea, Guinea Bissau, The Gambia and Senegal), spanning a highly endemic forested region in the south to a low endemic Sahelian region in the north. Analysis was performed on proportions of mixed genotype infections, genotypic diversity among isolates, multilocus standardized index of association, and inter-population differentiation. Results Each location had similar levels of pairwise genotypic diversity among isolates, although there were many more mixed parasite genotype infections in the south. Apart from a few isolates that were virtually identical, the multilocus index of association was not significant in any population. Genetic differentiation between populations was low (most pairwise FST values < 0.03), and an overall test for isolation by distance was not significant. Conclusions Although proportions of mixed genotype infections varied with endemicity as expected, population genetic structure was similar across the diverse sites. Very substantial reduction in transmission would be needed to cause fragmented or epidemic sub-structure in this region. PMID:22759447

  18. Africa.

    ERIC Educational Resources Information Center

    Happel, Sue; Loeb, Joyce

    Although the activities in this unit are designed primarily for students in the intermediate grades, the document's text, illustrations, and bibliographic references are suitable for anyone interested in learning about Africa. Following a brief introduction and map work, the document is arranged into six sections. Section 1 traces Africa's history…

  19. Africa.

    ERIC Educational Resources Information Center

    Martz, Carlton

    2001-01-01

    This publication explores issues related to Africa. It examines the U.S. response to the Barbary pirate states (Morocco, Algiers, Tunis, Tripoli) in the early 19th century; the current AIDS crisis in Africa; and 14th century Mali and other Islamic lands through the eyes of Ibn Battuta, who traveled throughout the Muslim world. Each article…

  20. Satellite-based Dust Source Identification over North Africa: Diurnal Cycle, Meteorological Controls, and Interannual Variability

    NASA Astrophysics Data System (ADS)

    Schepanski, Kerstin; Tegen, Ina; Macke, Andreas

    2010-05-01

    Mineral dust aerosol emitted from arid and semi-arid areas impacts on the weather and climate system by affecting e.g. radiation fluxes and nutrient cycles. To estimate the effect of dust aerosol, detailed knowledge on the spatio-temporal distribution of active dust sources is necessary. For a better representation of dust-related processes in numerical models and climate change projections the knowledge on the natural variability of dust source activity has to be improved. As dust sources are mostly located over remote areas satellite observations are suitable for identifying active dust sources. The accuracy of dust source identification using such an indirect method is limited by the temporal resolution and the ambiguities of the retrieval. Here, a data set on the spatial (1°x1°) and temporal (3-hourly) distribution of dust source activations (DSA) over North Africa is compiled by analyzing 15-minute Meteosat Second Generation (MSG) infra-red (IR) dust index images since March 2006. The index is designed using radiances measured by the Spinning Enhanced Visible and Infra-Red Imager (SEVIRI) on-board MSG at 8.7 µm, 10.8 µm and 12.0 µm which are converted to brightness temperatures (BTs). To strengthen the dust signal, differences of BTs are used to compute RGB-composite images. This newly data set providing information on the diurnal cycle of dust emission has been used (1) to identify most active dust source areas, and (2) to investigate on the temporal distribution of DSAs. Over the Sahara Desert 65% of dust sources become active during 06-09 UTC pointing towards an important role of the break-down of the nocturnal low-level jet (LLJ) for dust mobilization besides other meteorological features like density currents, haboobs, and cyclones. Furthermore the role of the nocturnal LLJs for dust mobilization over the Sahara is investigated by weather observations and a regional modeling study. Four years of DSA observations indicate an interannual variability in

  1. Similarities in the Paleozoic successions of north Africa and Arabia and implications for petroleum exploration

    SciTech Connect

    Clark-Lowes, D.D. )

    1988-08-01

    From field studies in southwest Libya and northwest Saudi Arabia, the facies of the Paleozoic succession of the north African/Arabian stable cratonic margin of Gondwanaland are interpreted as fluvial, estuarine, deltaic, shallow marine, and glacial deposits. The facies of the Saq and Tabuk Formations of Saudi Arabia bear witness to a sedimentary history that is very similar to that of north Africa, the Saq Formation (Cambrian-Arenig) being equivalent to the Hassaouna Formation of Libya and the Tabuk Formation being subdivided and correlated using well-dated shale members to the following formations: Haouaz (Llanvirn-Llandeilo), Melez-Chograne (Caradoc), Memouniat (Ashgill), Tanezzuft/Acacus (Llandovery-Ludlow), and Tadrart (Gedinnian -Emsian). The Cambrian-Ordovician succession comprises Nubian-type fluvial and estuarine sandstones which pass up to regressive deltaic/shallow marine sequences overlain by Upper Ordovician glacial deposits that lie in deeply incised paleovalleys recorded from Saudi Arabia and north Africa. The Silurian succession comprises the deposits of a postglacial marine transgression of vast lateral extent and a subsequent regression, the sandstones of which are markedly diachronous. The Lower Devonian succession comprises fining-upward retrogradational deltaic (transgressive) sequences of Nubian-type sandstones (fluvial to shallow marine) which form widespread blanket sandstone bodies. The prospectivity of these strata is well known from Algeria in the west to Jordan in the east, the Llandoverian oil-prone source rocks providing the key to Cambrian-Ordovician and Lower Devonian plays. The significance of underlying paleovalley-fill fluvioglacial sandstones as linear reservoir targets has yet to be fully appreciated.

  2. Spatiotemporal variability analysis of vegetation cover status for drought study purposes over North Africa using 8-km NDVI-GIMMS data

    NASA Astrophysics Data System (ADS)

    Chokmani, K.; El Alem, A.; Chebana, F.

    2013-12-01

    Africa is considered as the second driest continent in the world behind Australia, its arid lands cover approximately 60 percent. Droughts that hit the continent in recent decades and land degradations at the margins of deserts, particularly for countries neighboring the Sahara such as Algeria, Morocco, and Tunisia have renewed concerns about desertification progress. For a better understanding to the complete nature of drought and the degree in which human activities and climate changes contribute to its development, it is imperative to determine this phenomenon more accurately. Previous drought assessments had several weaknesses making them less reliable. Indeed, standard measurement methods, based on an unevenly distributed sampling point network, are unrepresentative neither for spatial distribution nor for temporal frequency of desertification. As an alternative to these conventional methods, remote sensing data could offer the needed spatial and temporal coverage. In fact, drought study is possible through monitoring vegetation and/or temperature conditions using vegetation and/or temperatures driven indices. Thus, several indices including the Normalized Difference Vegetation Index (NDVI), Transformed Difference Vegetation Index (TDVI), Soil Adjusted Vegetation Index (SAVI), and Temperature Condition Index (TCI), have been employed using various satellite sensors such as Advanced Very High Resolution Radiometer (AVHRR), Landsat Thematic Mapper (TM), and MODerate Resolution Imaging Spectroradiometer (MODIS) to monitor and analyze drought in various regions of the world. In this study, the AVHRR NDVI-GIMMS data at 8-km spatial resolution were used to study the evolution of the vegetation cover status in North Africa's countries over 25 years. The NDVI-GIMMS data were highly correlated with the rainfall in situ samples collected on different cities over the North Africa's countries as the determination coefficient (R2) was about 0.96. The vegetation cover study

  3. Wind energy resource atlas. Volume 2. The North Central Region

    SciTech Connect

    Freeman, D.L.; Hadley, D.L.; Elliott, D.L.; Barchet, W.R.; George, R.L.

    1981-02-01

    The North Central atlas assimilates six collections of wind resource data: one for the region and one for each of the five states that compose the North Central region (Iowa, Minnesota, Nebraska, North Dakota, and South Dakota). At the state level, features of the climate, topography and wind resource are discussed in greater detail than is provided in the regional discussion, and that data locations on which the assessment is based are mapped. Variations, over several time scales, in the wind resource at selected stations in each state are shown on graphs of monthly average and international wind speed and power, and hourly average wind speed for each season. Other graphs present speed direction and duration frequencies of the wind at these locations.

  4. Variability and trends of local/regional scale surface climate in northern Africa during the twentieth century

    NASA Astrophysics Data System (ADS)

    Djomou, Zéphirin Yepdo; Monkam, David; Woafo, Paul

    2014-08-01

    Four regions are detected in northern Africa (20° W-40° E, 0-30° N) by applying the cluster analysis method on the annual rainfall anomalies of the period 1901-2000. The first region (R1), an arid land, covers essentially the north of 17.75° N from west to east of the study zone. The second region (R2), a semiarid land with a Sahelian climate, less warm than the dry climate of R1, is centred on Chad, with almost regular extension to the west towards Mauritania, and to the east, including the north of the Central African Republic and the Sudan. The region 3 (R3), a wet land, is centred on the Ivory Coast and covers totally Liberia, the south part of Ghana, Togo, Benin and the southwest of Nigeria. The fourth region (R4), corresponding to the wet equatorial forest, covers a part of Senegal, the Central Africa, the south of Sudan and a part of Ethiopia. An analysis of observed temperature and precipitation variability and trends throughout the twentieth century over these regions is presented. Summer, winter and annual data are examined using a range of variability measures. Statistically, significant warming trends are found over the majority of regions. The trends have a magnitude of up to 1.5 K per century. Only a few precipitation trends are statistically significant. Regional temperature and precipitation show pronounced variability at scales from interannual to multi-decadal. The interannual variability shows significant variations and trends throughout the century, the latter being mostly negative for precipitation and both positive and negative for temperature. Temperature and precipitation anomalies show a chaotic-type behaviour in which the regional conditions oscillate around the long-term mean trend and occasionally fall into long-lasting (up to 10 years or more) anomaly regimes. A generally modest temporal correlation is found between anomalies of different regions and between temperature and precipitation anomalies for the same region. This

  5. Seismotectonic Analysis for the KZN region of South Africa

    NASA Astrophysics Data System (ADS)

    Singh, M.

    2012-04-01

    Recently, devastating earthquakes and tsunamis have shocked the modern world (Japan [April 7 2011, Mw 9.0, loss of life and destruction of infrastructure, 15,457 deaths 5,389 injured, US300billion loss (Japanese National Police Agency 2011)], New Zealand [21 February 2011, Mw 6.3, 148 killed], Haiti [12 January 2010, Mw 7.0, estimated 316 000 killed and 300 000 injured]. These earthquakes have caused large scale damage to the built environment not to mention the high number of fatalities. The KZN coastal region is also fast developing especially towards the north of Durban CBD (Cornubia [New development near Umhlanga, 25 Billion Rands investment], Gateway/Umhlanga Business District, Moses Mabida Stadium (cost of R3.4 billion ), King Shaka International Airport at a cost of R6.8 billion, Dube Tradeport to be developed next to the airport at a cost of R5 billion, as well as the development of the Richards Bay Industrial Development Zone . The KZN is home to 10 million inhabitants with a relatively denser population distribution around the Durban and Pietermaritzburg CBDs. With the increasing amount of investment towards the north coast of Durban, the population distribution will migrate to these areas. These areas now become 'vulnerable' to rare, infrequent and potentially devastating natural disasters like earthquakes. One of the first steps to understand and plan for an earthquake occurrence is through a seismic hazard and risk assessment. The seismic hazard and risk method has well been established since 1968 (see Cornell (1968); Veneziano et al., (1984); Bender and Perkins (1993); McGuire (1993); McGuire and Toro (2008); Kijko and Graham (1998); Kijko and Sellevoll, (1989, 1992)). The components of a seismic risk assessment (SRA) include several building blocks namely: the development of the earthquake catalogue, seismotectonic model, attenuation models, seismic hazard assessment (SHA), vulnerability assessment and seismic risk computations. The seismotectonic

  6. North polar region of Mars - Imaging results from Viking 2

    NASA Technical Reports Server (NTRS)

    Cutts, J. A.; Blasius, K. R.; Briggs, G. A.; Carr, M. H.; Masursky, H.; Greeley, R.

    1976-01-01

    During October 1976, the Viking 2 orbiter acquired approximately 700 high-resolution images of the north polar region of Mars. These images confirm the existence at the north pole of extensive layered deposits largely covered over with deposits of perennial ice. An unconformity within the layered deposits suggests a complex history of climate change during their time of deposition. A pole-girdling accumulation of dunes composed of very dark materials is revealed by the Viking cameras. The entire region is devoid of fresh impact craters. Rapid rates of erosion or deposition are implied. A scenario for polar geological evolution, involving two types of climate change, is proposed.

  7. On the Role of Flash Floods for Dust Emission over North Africa: Alluvial Sediments acting as Dust Source

    NASA Astrophysics Data System (ADS)

    Schepanski, K.; Klueser, L.; Tegen, I.

    2014-12-01

    Studies analyzing satellite dust products show that numerous dust sources are located in the foothills of arid and semi-arid mountain regions. There, alluvial sediments deposited on valley bottoms and flood plains are very susceptible to wind erosion and frequently serve as dust source. This study focuses on the spatio-temporal distribution of dust source activation events over the mountain foothills and flood plains over North Africa. Satellite dust retrievals with sub-daily resolution such as from Meteosat Second Generation (MSG) Spinning Enhanced Visible and InfraRed Imager (SEVIRI) and METOP A/B Infrared Atmospheric Sounding Interferometer (IASI) instruments are used to identify dust source regions. Identified dust source regions are then linked to soil properties and land type classification data sets. Information on the mineralogical composition of transported dust inferred from IASI observation are used (a) to investigate the impact of different source geomorphologies and thus different radiative properties of airborne dust particles, and (b) to estimate the contribution of dust uplift from alluvial sediments compared to dust emission from non-hydrological sources. Ultimately, this study contributes to the understanding of controlling mechanism on the interannual variability of dust source activation and will improve current dust emission modules coupled to atmosphere models.

  8. AMMA-CATCH studies in the Sahelian region of West-Africa: An overview

    NASA Astrophysics Data System (ADS)

    Lebel, Thierry; Cappelaere, Bernard; Galle, Sylvie; Hanan, Niall; Kergoat, Laurent; Levis, Samuel; Vieux, Baxter; Descroix, Luc; Gosset, Marielle; Mougin, Eric; Peugeot, Christophe; Seguis, Luc

    2009-08-01

    SummaryThe African Monsoon Multidisciplinary Analysis (AMMA) is an international and interdisciplinary experiment designed to investigate the interactions between atmospheric, oceanic and terrestrial systems and their joint controls on tropical monsoon dynamics in West Africa. This special issue reports results from a group of AMMA studies regrouped in the component " Couplage de l'Atmosphère Tropicale et du Cycle Hydrologique" (CATCH). AMMA-CATCH studies focus on measuring and understanding land surface properties and processes in West Africa, the role of terrestrial systems in altering boundary layer dynamics, and thus the potential that surface hydrology and biology, and human land use practices, may directly or indirectly affect monsoon dynamics and rainfall in the region. AMMA-CATCH studies focus on three intensively instrumented mesoscale sites in Mali, Niger and Benin that sample across the 100-1300 mm/annum rainfall gradient of the Sahel, Sudan and North-Guinean bioclimatic zones. Studies report on: (i) surface-boundary layer interactions that may influence atmospheric convergence and convective processes and thus rainfall type, timing and amount; (ii) vegetation dynamics at seasonal to decadal time-scales that may respond to, and alter, atmospheric processes; (iii) surface-atmosphere fluxes of heat, water and carbon dioxide that directly influence the atmosphere; (iv) soil moisture variability in space and time that provide the proximate control on vegetation activity, evapotranspiration and energy balance; and (v) local and mesoscale modeling of hydrology and land surface-atmosphere exchanges to assess their role in the hydrological, atmospheric and rainfall dynamics of West Africa. The AMMA-CATCH research reported in this issue will be extended in future years as measurements and analysis continue and are concluded within the context of both CATCH and the wider AMMA study. This body of research will contribute to an improved understanding of the

  9. Languages of the Middle East and North Africa. A Survey of Materials for the Study of the Uncommonly Taught Languages.

    ERIC Educational Resources Information Center

    Johnson, Dora E.; And Others

    This is an annotated bibliography of basic tools of access for the study of the uncommonly taught languages of the Middle East and North Africa. It is one of eight fascicles which constitute a revision of "A Provisional Survey of Materials for the Study of the Neglected Languages" (CAL 1969). The emphasis is on materials for the adult learner…

  10. Orientalism(s), World Geography Textbooks, and Temporal Paradox: Questioning Representations of Southwest Asia and North Africa

    ERIC Educational Resources Information Center

    Zagumny, Lisa; Richey, Amanda B.

    2013-01-01

    In this critical discourse analysis of six high-school world geography textbooks, we explore how constructions and representations of North Africa and Southwest Asia have served to reinforce Orientalist discourse in formal curriculum. Visual and written representations in these textbooks were overwhelmingly confounded by a traditional/modern…

  11. A Human Economy: A "Third Way" for the Future of Young People in the Middle East and North Africa

    ERIC Educational Resources Information Center

    Zaalouk, Malak

    2014-01-01

    This paper looks at the vulnerability of today's youth worldwide, with a particular focus on the Middle East and North Africa (MENA), where the proportion of citizens aged 12-24 is particularly high at one-third of the total population. Cursed with poor education and few work opportunities, the youth unemployment rate has risen to 50 per cent…

  12. Alien phytogeographic regions of southern Africa: numerical classification, possible drivers, and regional threats.

    PubMed

    Hugo, Sanet; Van Rensburg, Berndt J; Van Wyk, Abraham E; Steenkamp, Yolande

    2012-01-01

    The distributions of naturalised alien plant species that have invaded natural or semi-natural habitat are often geographically restricted by the environmental conditions in their new range, implying that alien species with similar environmental requirements and tolerances may form assemblages and characterise particular areas. The aim of this study was to use objective numerical techniques to reveal any possible alien phytogeographic regions (i.e. geographic areas with characteristic alien plant assemblages) in southern Africa. Quarter degree resolution presence records of naturalised alien plant species of South Africa, Lesotho, Swaziland, Namibia and Botswana were analysed through a divisive hierarchical classification technique, and the output was plotted on maps for further interpretation. The analyses revealed two main alien phytogeographic regions that could be subdivided into eight lower level phytogeographic regions. Along with knowledge of the environmental requirements of the characteristic species and supported by further statistical analyses, we hypothesised on the main drivers of alien phytogeographic regions, and suggest that environmental features such as climate and associated biomes were most important, followed by human activities that modify climatic and vegetation features, such as irrigation and agriculture. Most of the characteristic species are not currently well-known as invasive plant species, but many may have potential to become troublesome in the future. Considering the possibility of biotic homogenization, these findings have implications for predicting the characteristics of the plant assemblages of the future. However, the relatively low quality of the dataset necessitates further more in-depth studies with improved data before the findings could be directly beneficial for management. PMID:22574145

  13. Alien Phytogeographic Regions of Southern Africa: Numerical Classification, Possible Drivers, and Regional Threats

    PubMed Central

    Hugo, Sanet; Van Rensburg, Berndt J.; Van Wyk, Abraham E.; Steenkamp, Yolande

    2012-01-01

    The distributions of naturalised alien plant species that have invaded natural or semi-natural habitat are often geographically restricted by the environmental conditions in their new range, implying that alien species with similar environmental requirements and tolerances may form assemblages and characterise particular areas. The aim of this study was to use objective numerical techniques to reveal any possible alien phytogeographic regions (i.e. geographic areas with characteristic alien plant assemblages) in southern Africa. Quarter degree resolution presence records of naturalised alien plant species of South Africa, Lesotho, Swaziland, Namibia and Botswana were analysed through a divisive hierarchical classification technique, and the output was plotted on maps for further interpretation. The analyses revealed two main alien phytogeographic regions that could be subdivided into eight lower level phytogeographic regions. Along with knowledge of the environmental requirements of the characteristic species and supported by further statistical analyses, we hypothesised on the main drivers of alien phytogeographic regions, and suggest that environmental features such as climate and associated biomes were most important, followed by human activities that modify climatic and vegetation features, such as irrigation and agriculture. Most of the characteristic species are not currently well-known as invasive plant species, but many may have potential to become troublesome in the future. Considering the possibility of biotic homogenization, these findings have implications for predicting the characteristics of the plant assemblages of the future. However, the relatively low quality of the dataset necessitates further more in-depth studies with improved data before the findings could be directly beneficial for management. PMID:22574145

  14. Atmospheric transportation of marihuana pollen from North Africa to the Southwest of Europe

    NASA Astrophysics Data System (ADS)

    Cabezudo, Baltasar; Recio, Marta; Sánchez-Laulhé, JoséMaŕia; Trigo, María Del Mar; Toro, Francisco Javier; Polvorinos, Fausto

    As a result of aerobiological samples taken on the Costa del Sol (S. Spain), Cannabis sativa L. (marihuana) pollen was detected from May to September 1991-1996, always sporadically and usually during the afternoons. Sampling was by two volumetric spore traps set up in Malaga and Estepona, two coastal towns approximately 90 km apart. A study of the days when this pollen was recorded points to the movement of air masses from North Africa to southern Spain. Furthermore, the isentropic air trajectories calculated for these days reinforce the possibility of the pollen originating in marihuana plantations in northern Morocco (Rif). This study demonstrates the application of aerobiology to the control of the source, quantity and phenology of the crop.

  15. Analyzing the implementation of the rural allowance in hospitals in North West Province, South Africa.

    PubMed

    Ditlopo, Prudence; Blaauw, Duane; Bidwell, Posy; Thomas, Steve

    2011-01-01

    Using a policy analysis framework, we analyzed the implementation and perceived effectiveness of a rural allowance policy and its influence on the motivation and retention of health professionals in rural hospitals in the North West province of South Africa. We conducted 40 in-depth interviews with policy-makers, hospital managers, nurses, and doctors at five rural hospitals and found weaknesses in policy design and implementation. These weaknesses included: lack of evidence to guide policy formulation; restricting eligibility for the allowance to doctors and professional nurses; lack of clarity on the definition of rural areas; weak communication; and the absence of a monitoring and evaluation framework. Although the rural allowance was partially effective in the recruitment of health professionals, it has had unintended negative consequences of perceived divisiveness and staff dissatisfaction. Government should take more account of contextual and process factors in policy formulation and implementation so that policies have the intended impact. PMID:21730996

  16. Early Tertiary mammals from North Africa reinforce the molecular Afrotheria clade

    PubMed Central

    Tabuce, Rodolphe; Marivaux, Laurent; Adaci, Mohammed; Bensalah, Mustapha; Hartenberger, Jean-Louis; Mahboubi, Mohammed; Mebrouk, Fateh; Tafforeau, Paul; Jaeger, Jean-Jacques

    2007-01-01

    The phylogenetic pattern and timing of the radiation of mammals, especially the geographical origins of major crown clades, are areas of controversy among molecular biologists, morphologists and palaeontologists. Molecular phylogeneticists have identified an Afrotheria clade, which includes several taxa as different as tenrecs (Tenrecidae), golden moles (Chrysochloridae), elephant-shrews (Macroscelididae), aardvarks (Tubulidentata) and paenungulates (elephants, sea cows and hyracoids). Molecular data also suggest a Cretaceous African origin for Afrotheria within Placentalia followed by a long period of endemic evolution on the Afro-Arabian continent after the mid-Cretaceous Gondwanan breakup (approx. 105–25 Myr ago). However, there was no morphological support for such a natural grouping so far. Here, we report new dental and postcranial evidence of Eocene stem hyrax and macroscelidid from North Africa that, for the first time, provides a congruent phylogenetic view with the molecular Afrotheria clade. These new fossils imply, however, substantial changes regarding the historical biogeography of afrotheres. Their long period of isolation in Africa, as assumed by molecular inferences, is now to be reconsidered inasmuch as Eocene paenungulates and elephant-shrews are here found to be related to some Early Tertiary Euramerican ‘hyopsodontid condylarths’ (archaic hoofed mammals). As a result, stem members of afrotherian clades are not strictly African but also include some Early Paleogene Holarctic mammals. PMID:17329227

  17. Regional climate change projections over southern Africa: Benefits of a high resolution climate change simulation

    NASA Astrophysics Data System (ADS)

    Haensler, A.; Hagemann, S.; Jacob, D.

    2009-12-01

    The southern African region is known to be a biodiversity hotspot but future climate change is likely to have a major influence on the biodiversity. To estimate the impacts of climate change on the biosphere high resolution climate information is needed for both current and future conditions. In the framework of the BIOTA South project we are therefore applying the regional climate model (RCM) REMO of the Max-Planck-Institute for Meteorology (MPI-M) over the southern African region. The model is integrated for a transient climate change simulation for the time period 1960 to 2100 at 1/2 degree and 1/6 degree horizontal resolution using a double-nesting approach. The 1/6 degree simulation is the first long-term climate projection for southern Africa on such a high horizontal resolution. The boundary forcing for the 1/2 degree projection is taken from a global ECHAM5/MPIOM IPCC A1B scenario simulation. In the current study we will analyse projected changes on the hydrological cycle, thereby focusing on the Orange river catchment and on the main BIOTA research transect, which spans from the north-east corner of Namibia to the Cape region in the South. In order to quantify the impact of model resolution on the projected changes we will intercompare the two REMO simulations and the ECHAM5/MPIOM forcing data. A comparison for the high resolution REMO validation simulation and its forcing ERA40 data already revealed an added value in the representation of the seasonal rainfall characteristics for the region. The benefits of using high resolution RCM data for climate change studies will be highlighted and uncertainties introduced by the application of an RCM will be discussed.

  18. Carbon Erosion in the Great Karoo Region of South Africa

    NASA Astrophysics Data System (ADS)

    Krenz, Juliane; Greenwood, Philip; Kuhn, Brigitte; Foster, Ian; Boardman, John; Meadows, Mike; Kuhn, Nikolaus

    2015-04-01

    Work undertaken in the seasonally arid upland areas of the Great Karoo region of South Africa has established a link between land degradation and overgrazing which began in the second half of the 18th century when European farmers first settled the area. Ongoing land use change and shifting rainfall patterns resulted in the development of badlands on foot slopes of upland areas, and gully systems on valley bottoms. As a consequence of agricultural intensification and overgrazing, accompanied by a higher water demand, many small reservoirs were constructed, most of which are now in-filled with sediment. The deposited material serves as an environmental archive by which land use change over the last 100 years can be analysed, but with a particular focus on erosion and deposition of soil-associated carbon (C). It is assumed that erosion caused an initial flush of carbon rich soil which was subsequently buried and stored off-site. Despite this assumption, however the net-effect of erosion on carbon dioxide emissions is still unknown. In this project, preliminary results are presented from an investigation to determine whether land degradation in the Karoo has resulted in a shift from a net sink of C to a net source of C. Firstly, a high resolution digital elevation model was generated and erosion modelling was then employed to create an erosion risk map showing areas most prone to erosion. Information from the model output then served as the basis for ground-truthing and on-site erosion mapping. Secondly, sediment deposits from silted reservoirs were analysed for varying physicochemical parameters, in order to reconstruct spatial patterns of erosion and deposition. Analysis of total carbon (TC) content revealed a sharp decrease with decreasing depth. This provisionally suggests that land degradation during and after post-European settlement probably led to accelerated erosion of the relatively fertile surface soils. This presumably resulted in the rapid in-filling of

  19. Drug policy and harm reduction in the Middle East and North Africa: The role of civil society.

    PubMed

    Aaraj, Elie; Jreij Abou Chrouch, Micheline

    2016-05-01

    Civil society organizations (CSOs) in Middle East and North Africa (MENA) are the principal partners of government in scaling up the response to HIV and in implementing national policies. In return, CSOs expect endorsement of their work by the governments. Some CSOs face weaknesses and need capacity-building in order for them to reach the level of response required for reducing drug-related harm in this region. Substance use and the transmission of HIV are increasing in the MENA region. The limited data available on drug use show that there are approximately 630,000 people who inject drugs (PWID) across the region. The HIV epidemic remains concentrated among PWID and other key populations in the region. Comprehensive harm reduction programs which include prevention, care, and HIV treatment for PWID are being implemented by CSOs. This could not happen without the presence of a conducive environment which has been facilitated by the CSOs, and which aims to lead to a positive response in health policies, and thus to harm reduction programs in some countries in the region. However, based on the international data, antiretroviral therapy (ART) coverage remains low in these countries, even if the number of people living with HIV (PLHIV) receiving ART is increasing. This increase can sometimes mask important challenges in equity: in several countries PWID are the most likely to be infected with HIV while being the least likely to be receiving care and ART. Therefore, concentrated efforts need to continue toward the goal of having mainstream harm reduction approaches in region. PMID:27140430

  20. Regional source properties of the North Korean nuclear explosions

    NASA Astrophysics Data System (ADS)

    Hong, T.

    2009-12-01

    Seismic analyses based on regional waveforms receive increasing attention for discrimination and source studies of recent moderate-size underground nuclear explosions (UNEs). Two North Korean underground nuclear explosion tests were conducted in 9 October 2006 and 25 May 2009. The Noth Korean UNEs were well observed by dense regional seismic networks with high signal-to-noise ratios. The source properties of the two North Korean UNEs are estimated using source-spectral inversions of regional phases. Ray-path effects including attenuation are corrected in the inversion. The source properties of the UNEs are compared each other. The apparent moments of high-frequency regional phases of the 2009 UNE are estimated to be about 5 times greater than those of the 2006 UNE. The corner frequencies and overshoot parameters are determined to be similar between the UNEs. The North Korean UNEs are well discriminated from natural earthquakes using P/S spectral ratios. The S waves from the North Korean UNEs display fairly weak overshooting feature in the spectra unlike P waves.

  1. North Carolina and the Southern Regional Education Board, December 2014

    ERIC Educational Resources Information Center

    Southern Regional Education Board (SREB), 2014

    2014-01-01

    This document details North Carolina's participation in Southern Regional Education Board (SREB) programs and services from December 2013 through November 2014. Appropriations from member states support SREB's core operations and general services. SREB leverages the long-standing commitment of member states to attract external funding for an array…

  2. Effective Lidar Ratios of Dense Dust Aerosol Layers over North Africa Observed by the CALIPSO Lidar

    NASA Astrophysics Data System (ADS)

    Liu, Z.; Winker, D. M.; Omar, A. H.; Vaughan, M.; Trepte, C. R.; Hu, Y.; Hostetler, C. A.; Sun, W.; Lin, B.

    2009-12-01

    measurement data with the 5D-PDF CAD algorithm applied. The effective lidar ratios computed for the opaque dust layers over the North Africa (12N-30N), one of the largest source regions in the world, have a relatively broad distribution, with a mean/median value of 38.5/36.4 sr at 532 nm and 50.3/47.7 sr at 1064 nm. The experimentally determined values are in good agreement with the modeling results for Saharan dust aerosols. Monte-Carlo simulations have also been performed to examine the impact of multiple scattering. The results show that multiple scattering generally has a small impact on the effective lidar (multiple scattering factor at the layer base > 0.9). However, when the dust extinction is > ~ 2/km, the multiple scattering impact can increase significantly. A closer examination of the depolarization ratio profiles in the dense dust layers shows a general agreement with the multiple scattering simulations.

  3. Albatross species demonstrate regional differences in North Pacific marine contamination

    USGS Publications Warehouse

    Finkelstein, M.; Keitt, B.S.; Croll, D.A.; Tershy, B.; Jarman, Walter M.; Rodriguez-Pastor, S.; Anderson, D.J.; Sievert, P.R.; Smith, D.R.

    2006-01-01

    Recent concern about negative effects on human health from elevated organochlorine and mercury concentrations in marine foods has highlighted the need to understand temporal and spatial patterns of marine pollution. Seabirds, long-lived pelagic predators with wide foraging ranges, can be used as indicators of regional contaminant patterns across large temporal and spatial scales. Here we evaluate contaminant levels, carbon and nitrogen stable isotope ratios, and satellite telemetry data from two sympatrically breeding North Pacific albatross species to demonstrate that (1) organochlorine and mercury contaminant levels are significantly higher in the California Current compared to levels in the high-latitude North Pacific and (2) levels of organochlorine contaminants in the North Paci.c are increasing over time. Black-footed Albatrosses (Phoebastria nigripes) had 370-460% higher organochlorine (polychlorinated biphenyls [PCBs], dichlorodiphenyltrichloroethanes [DDTs]) and mercury body burdens than a closely related species, the Laysan Albatross (P. immutabilis), primarily due to regional segregation of their North Pacific foraging areas. PCBs (the sum of the individual PCB congeners analyzed) and DDE concentrations in both albatross species were 130-360% higher than concentrations measured a decade ago. Our results demonstrate dramatically high and increasing contaminant concentrations in the eastern North Pacific Ocean, a finding relevant to other marine predators, including humans. ?? 2006 by the Ecological Society of America.

  4. A human economy: A ``third way'' for the future of young people in the Middle East and North Africa

    NASA Astrophysics Data System (ADS)

    Zaalouk, Malak

    2014-06-01

    This paper looks at the vulnerability of today's youth worldwide, with a particular focus on the Middle East and North Africa (MENA), where the proportion of citizens aged 12-24 is particularly high at one-third of the total population. Cursed with poor education and few work opportunities, the youth unemployment rate has risen to 50 per cent in this region. There is a consequent lack of participation at all levels, and a large number of youth are showing symptoms of low self-esteem, frustration, anger and unrest. After discussing the outcomes of years of an inhuman economic system on a global level, this article points to a more humane and empowering path. The author argues that, instead of continuing with profit-oriented capitalism or relying on the informal sector, the co-operative way represents a third alternative to existing economic sectors within the dominant contemporary economic system. The article analyses the many benefits of this path for the realisation of a humane economy. In so doing, it touches on issues of equity and social protection. Finally, the article outlines what needs to be done if this is to be a viable solution for a human economy. While giving many examples of successful co-operative enterprises worldwide, the author singles out the MENA region as one which could also benefit from the new trends outlined.

  5. Migrations of European honey bee lineages into Africa, Asia, and North America during the Oligocene and Miocene

    NASA Astrophysics Data System (ADS)

    Kotthoff, Ulrich; Wappler, Torsten; Engel, Michael

    2013-04-01

    Today honey bees, principally the western honey bee, Apis mellifera, represent a multi-billion dollar agricultural industry. Through the efforts of humans they have become established well outside of their modern native ranges, having been introduced multiple times into the Americas, Australia, New Zealand, New Caledonia, and many areas of Oceania. The native, i.e., non-human influenced, distribution and migration of honey bee species and populations has been a matter of serious and continued debate. Apicultural dogma informs us that the center of origin of honey bees (genus Apis) resides in Asia, with subsequent migration and diversification into Europe and Asia. Recent population genetic studies of the western honey bee, Apis mellifera, slightly modified this received wisdom by suggesting that this species originated in Africa and subsequently reinvaded Eurasia. Research into the historical biogeography of honey bees has ignored entirely the abundant fossil evidence distributed through a variety of Late Paleogene (Oligocene) and Early Neogene (Miocene) deposits, a diversity which is predominantly European in origin, particularly among the most basal species of the genus. We have examined the morphological disparity and affinities of the full living and fossil diversity of honey bees ranging from their earliest origins to the present day. This analysis indicates that honey bees exhibited a greater morphological disparity during the Oligocene and Miocene epochs, a time when the principal lineages were established, and that Apis apparently originated in Europe, spreading from there into Asia, Africa, and North America, with subsequent diversification in the former two regions and extinction in the latter. During the human migrations and colonization honey bees were once again introduced multiple times into the Americas, as well as into Australia and Asia.

  6. The influence of source landforms, antecedent precipitation, and winds on dust events in North Africa

    NASA Astrophysics Data System (ADS)

    Ballantine, John-Andrew Chapin

    This dissertation identifies conditions associated with dust storms in North Africa. The introductory chapter frames a conceptual model of how atmospheric dustiness is governed by static landforms, dynamic characteristics of the surface (represented by cumulative antecedent precipitation or CAP), and surface wind fields. Visibility at 225 meteorological stations across Africa, north of 10° north latitude, is used as a proxy for atmospheric dust. A map of landforms is created from a multiple endmember mixture analysis of MODIS satellite imagery to represent landforms. The ten landforms identified are alluvial surfaces, dunes, dry lakebeds, water, basaltic surfaces, mountains, regs, bedrock surfaces, sandsheets, and vegetated surfaces. Climatological and event-based statistics are used to determine relationships between parameters related to visibility, landforms, CAP, and wind speed. CAP represents dynamic changes in the erodibility of the surface including the sheltering effect of vegetation and delivery of erodible sediments. Surface wind velocities represent the winds that mobilize fine sediments to become dust. Alluvial surfaces, dunes, dry lakebeds, regs, bedrock, and sandsheets are more often associated with low visibility (<5 km) events than high. Negative correlations between median wind speed and the monthly frequency of visibility less than five kilometers (DEF-5) identify 33 stations where factors other than dust strongly influence the visibility record and these stations are removed. Results regarding the relationship between CAP and dustiness find that at Sahelian and southern Saharan locations, vulnerability to dust emissions is related to drought reducing vegetation cover. At central, northern, and eastern Saharan locations, vulnerability to dust emissions is related to wet conditions, probably as a result of fresh sediment being deposited at erodible locations in the landscape. Wind speed results find that for any dust source, there is an

  7. On the orientation of pre-islamic temples of north Africa: a re-appraisal (new data in Africa proconsularis)

    NASA Astrophysics Data System (ADS)

    Belmonte, J. A.; Gaspar, A. T.; Betancort, A. P.; Marrero, R.

    Since the late 1990s, our research group has embarked on a systematic archaeoastronomical study of archaeological sites in the Maghreb. Earlier campaigns were devoted to Tunisia, Morocco and Libya (see e.g. Belmonte et. Al.1998, 1999 and 2002). In this short report we will present part of the data obtained in a field campaign carried out in winter 2002, analyzing the results yielded on early 50 ancient sacred structures (temples, churches, earlier mosques and mausoleums) of an extended area in Northern Tunisia (ancient Africa Proconsularis). These data were not discussed in previous reports on similar structures (e.g. Esteban at.al.2001) , although in a previous paper (Belmonte et.al.2003) we reported our results on the contemporary measured megalithic monuments. This paper will present the data of more than 30 temples and mausoleums of Roman era, 10 pre-Islamic Christian churches and a few earlier mosques. These new data will be discussed together with those obtained in previous campaigns in an attempt to shed some light on the possibility of astronomical alignments within this extended set of monuments (more than a hundred). Our results show that some astronomical patterns could be interpreted as solar ones. Interestingly, this solar tendency was continued by Christian churches until the arrival of Islam. This is a common feature to the other regions of early Christianity (see e.g. Romano 1992). Other curious patterns, including the planning of important cities could presumably be associated to the brightest stars of the sky, Sirius and Canopus. Finally, we will analyse how this astronomical tendencies managed to survive within the first Islamic orienting traditions.

  8. Neglected Tropical Diseases of the Middle East and North Africa: Review of Their Prevalence, Distribution, and Opportunities for Control

    PubMed Central

    Hotez, Peter J.; Savioli, Lorenzo; Fenwick, Alan

    2012-01-01

    The neglected tropical diseases (NTDs) are highly endemic but patchily distributed among the 20 countries and almost 400 million people of the Middle East and North Africa (MENA) region, and disproportionately affect an estimated 65 million people living on less than US$2 per day. Egypt has the largest number of people living in poverty of any MENA nation, while Yemen has the highest prevalence of people living in poverty. These two nations stand out for having suffered the highest rates of many NTDs, including the soil-transmitted nematode infections, filarial infections, schistosomiasis, fascioliasis, leprosy, and trachoma, although they should be recognized for recent measures aimed at NTD control. Leishmaniasis, especially cutaneous leishmaniasis, is endemic in Syria, Iran, Iraq, Libya, Morocco, and elsewhere in the region. Both zoonotic (Leishmania major) and anthroponotic (Leishmania tropica) forms are endemic in MENA in rural arid regions and urban regions, respectively. Other endemic zoonotic NTDs include cystic echinococcosis, fascioliasis, and brucellosis. Dengue is endemic in Saudi Arabia, where Rift Valley fever and Alkhurma hemorrhagic fever have also emerged. Great strides have been made towards elimination of several endemic NTDs, including lymphatic filariasis in Egypt and Yemen; schistosomiasis in Iran, Morocco, and Oman; and trachoma in Morocco, Algeria, Iran, Libya, Oman, Saudi Arabia, Tunisia, and the United Arab Emirates. A particularly noteworthy achievement is the long battle waged against schistosomiasis in Egypt, where prevalence has been brought down by regular praziquantel treatment. Conflict and human and animal migrations are key social determinants in preventing the control or elimination of NTDs in the MENA, while local political will, strengthened international and intersectoral cooperative efforts for surveillance, mass drug administration, and vaccination are essential for elimination. PMID:22389729

  9. Neglected tropical diseases of the Middle East and North Africa: review of their prevalence, distribution, and opportunities for control.

    PubMed

    Hotez, Peter J; Savioli, Lorenzo; Fenwick, Alan

    2012-01-01

    The neglected tropical diseases (NTDs) are highly endemic but patchily distributed among the 20 countries and almost 400 million people of the Middle East and North Africa (MENA) region, and disproportionately affect an estimated 65 million people living on less than US$2 per day. Egypt has the largest number of people living in poverty of any MENA nation, while Yemen has the highest prevalence of people living in poverty. These two nations stand out for having suffered the highest rates of many NTDs, including the soil-transmitted nematode infections, filarial infections, schistosomiasis, fascioliasis, leprosy, and trachoma, although they should be recognized for recent measures aimed at NTD control. Leishmaniasis, especially cutaneous leishmaniasis, is endemic in Syria, Iran, Iraq, Libya, Morocco, and elsewhere in the region. Both zoonotic (Leishmania major) and anthroponotic (Leishmania tropica) forms are endemic in MENA in rural arid regions and urban regions, respectively. Other endemic zoonotic NTDs include cystic echinococcosis, fascioliasis, and brucellosis. Dengue is endemic in Saudi Arabia, where Rift Valley fever and Alkhurma hemorrhagic fever have also emerged. Great strides have been made towards elimination of several endemic NTDs, including lymphatic filariasis in Egypt and Yemen; schistosomiasis in Iran, Morocco, and Oman; and trachoma in Morocco, Algeria, Iran, Libya, Oman, Saudi Arabia, Tunisia, and the United Arab Emirates. A particularly noteworthy achievement is the long battle waged against schistosomiasis in Egypt, where prevalence has been brought down by regular praziquantel treatment. Conflict and human and animal migrations are key social determinants in preventing the control or elimination of NTDs in the MENA, while local political will, strengthened international and intersectoral cooperative efforts for surveillance, mass drug administration, and vaccination are essential for elimination. PMID:22389729

  10. Water-ice clouds in the Martian North Polar Region

    NASA Astrophysics Data System (ADS)

    Tamppari, L. K.; Qu, Z.; Smith, M. D.; Bass, D. S.; Hale, A. S.

    2004-11-01

    There has been uncertainty about the amount of water cycling in and out of the polar region during the northern spring/summer timeframe, as evidenced by visible brightness changes in the residual polar cap from year to year which were originally though to be interannual variations (James and Martin, 1995; Kieffer, 1990). Subsequently, through comparison of Viking and Mariner 9 data sets, these variations were thought to be late season water deposition (Bass et al., 2000: Bass and Paige, 2000), perhaps in the form of direct condensation or snowfall. More recently, examination of multi-year MGS MOC data (Hale et al., 2004) opens this question again. Water cycling can be assessed using data sets by examination of water vapor, polar cap changes, and water-ice clouds. In this presentation, we examine the Mars Global Surveyor (MGS) Thermal Emission Spectrometer (TES) nadir pointed data in the north polar region of Mars during northern spring and summer to find and map water-ice clouds. Water-ice clouds, in the north polar region, have previously been tentatively identified in the Viking data (Tamppari and Bass, 2000), and some water-ice clouds identifications have been made in the north polar region during the MGS era (M. Smith, pers. comm., 2001). We present our results of water-ice clouds for 3 Mars years' spring and summer times, including opacities, spatial and temporal variations.

  11. The role of cryptotephra in refining the chronology of Late Pleistocene human evolution and cultural change in North Africa

    NASA Astrophysics Data System (ADS)

    Barton, R. N. E.; Lane, C. S.; Albert, P. G.; White, D.; Collcutt, S. N.; Bouzouggar, A.; Ditchfield, P.; Farr, L.; Oh, A.; Ottolini, L.; Smith, V. C.; Van Peer, P.; Kindermann, K.

    2015-06-01

    Sites in North Africa hold key information for dating the presence of Homo sapiens and the distribution of Middle Stone Age (MSA), Middle Palaeolithic (MP) and Later Stone Age (LSA) cultural activity in the Late Pleistocene. Here we present new and review recently published tephrochronological evidence for five cave sites in North Africa with long MSA/MP and LSA cultural sequences. Four tephra horizons have been identified at the Haua Fteah (Cyrenaica, Libya). They include cryptotephra evidence for the Campanian Ignimbrite (CI) eruption dating to ˜39 ka that allows correlation with other Palaeolithic sequences in the eastern Mediterranean and as far north as Russia. Cryptotephra have also been recorded from the Moroccan sites of Taforalt, Rhafas and Dar es-Soltane 1. At Taforalt the geochemical composition suggests a provenance in the Azores, while examples from Sodmein (Egypt) appear to derive from central Anatolia and another unknown source. In these latter examples chemical compositional data from relevant proximal volcanic centres is currently lacking so the identification of tephra in layers of known age and cultural association provides the first reliable age determinations for distal volcanic events and their geographical extent. The future potential for tephrochronological research in North Africa is also discussed.

  12. Learning about War and Peace in the Great Lakes Region of Africa

    ERIC Educational Resources Information Center

    Bird, Lyndsay

    2007-01-01

    Two-thirds of the world's conflicts are in Africa. In particular, the Great Lakes region (Rwanda, Burundi, Democratic Republic of Congo, Uganda and Tanzania) continues to see conflicts that are complex, extreme and seemingly intractable. By exploring the narrative experiences of those most affected by the conflicts in the region--specifically…

  13. North polar region of Mars: imaging results from viking 2.

    PubMed

    Cutts, J A; Blasius, K R; Briggs, G A; Carr, M H; Greeley, R; Masursky, H

    1976-12-11

    During October 1976, the Viking 2 orbiter acquired approximately 700 high-resolution images of the north polar region of Mars. These images confirm the existence at the north pole of extensive layered deposits largely covered over with deposits of perennial ice. An unconformity within the layered deposits suggests a complex history of climate change during their time of deposition. A pole-girdling accumulation of dunes composed of very dark materials is revealed for the first time by the Viking cameras. The entire region is devoid of fresh impact craters. Rapid rates of erosion or deposition are implied. A scenario for polar geological evolution, involving two types of climate change, is proposed. PMID:17797095

  14. North African petroleum geology: regional structure and stratigraphic overview of a hydrocarbon-rich cratonic area

    SciTech Connect

    O'Connor, T.E.; Kanes, W.H.

    1985-02-01

    North Africa, including Sinai, contains some of the most important hydrocarbon-producing basins in the world. The North African Symposium is devoted to examining the exploration potential of the North African margin in light of the most recent and promising exploration discoveries. The geologic variety of the region is extraordinary and can challenge any exploration philosophy. Of primary interest are the Sirte basin of Libya, which has produced several billion barrels of oil, and the Gulf of Suez, a narrow, evaporite-capped trough with five fields that will produce more than 5 billion bbl. Both are extensional basins with minimal lateral movement and with good source rocks in direct proximity to reservoirs. Structural models of these basins give firm leads for future exploration. More difficult to evaluate are the Tethyan realm basins of the northern Sinai, and the Western Desert of Egypt, the Cyrenaican Platform of Libya, and the Tunisia-Sicily shelf area, where there are only limited subsurface data. These basins are extensional in origin also, but have been influenced by lateral tectonics. Favorable reservoirs exist, but source rocks have been a problem locally. Structural models with strong stratigraphic response offer several favorable play concepts. The Paleozoic Ghadames basin in Libya, Tunisia, and Algeria has the least complex structural history, and production appears to be limited to small structures. A series of stratigraphic models indicates additional areas with exploration potential. The Paleozoic megabasin of Morocco, with its downfaulted Triassic grabens, remains an untested but attractive area.

  15. The Complex North Transition Region of Centaurus A: Radio Structure

    NASA Astrophysics Data System (ADS)

    Neff, Susan G.; Eilek, Jean A.; Owen, Frazer N.

    2015-04-01

    We present deep radio images of the inner ~50 kpc of Centaurus A, taken with the Karl G. Jansky Very Large Array at 90 cm. We focus on the Transition Regions between the inner galaxy—including the active nucleus, inner radio lobes, and star-forming disk—and the outer radio lobes. We detect previously unknown extended emission around the Inner Lobes, including radio emission from the star-forming disk. We find that the radio-loud part of the North Transition Region (NTR), known as the North Middle Lobe, is significantly overpressured relative to the surrounding interstellar medium. We see no evidence for a collimated flow from the active galactic nucleus through this region. Our images show that the structure identified by Morganti et al. as a possible large-scale jet appears to be part of a narrow ridge of emission within the broader, diffuse, radio-loud region. This knotty radio ridge is coincident with other striking phenomena: compact X-ray knots, ionized gas filaments, and streams of young stars. Several short-lived phenomena in the NTR, as well as the frequent re-energization required by the Outer Lobes, suggest that energy must be flowing through both Transition Regions at the present epoch. We suggest that the energy flow is in the form of a galactic wind.

  16. 82,000-year-old shell beads from North Africa and implications for the origins of modern human behavior

    PubMed Central

    Bouzouggar, Abdeljalil; Barton, Nick; Vanhaeren, Marian; d'Errico, Francesco; Collcutt, Simon; Higham, Tom; Hodge, Edward; Parfitt, Simon; Rhodes, Edward; Schwenninger, Jean-Luc; Stringer, Chris; Turner, Elaine; Ward, Steven; Moutmir, Abdelkrim; Stambouli, Abdelhamid

    2007-01-01

    The first appearance of explicitly symbolic objects in the archaeological record marks a fundamental stage in the emergence of modern social behavior in Homo. Ornaments such as shell beads represent some of the earliest objects of this kind. We report on examples of perforated Nassarius gibbosulus shell beads from Grotte des Pigeons (Taforalt, Morocco), North Africa. These marine shells come from archaeological levels dated by luminescence and uranium-series techniques to ≈82,000 years ago. They confirm evidence of similar ornaments from other less well dated sites in North Africa and adjacent areas of southwest Asia. The shells are of the same genus as shell beads from slightly younger levels at Blombos Cave in South Africa. Wear patterns on the shells imply that some of them were suspended, and, as at Blombos, they were covered in red ochre. These findings imply an early distribution of bead-making in Africa and southwest Asia at least 40 millennia before the appearance of similar cultural manifestations in Europe. PMID:17548808

  17. Dust Optical Properties Over North Africa and Arabian Peninsula Derived from the AERONET Dataset

    NASA Technical Reports Server (NTRS)

    Kim, D.; Chin, M.; Yu, H.; Eck, T. F.; Sinyuk, A.; Smirnov, A.; Holben, B. N.

    2011-01-01

    Dust optical properties over North Africa and the Arabian Peninsula are extracted from the quality assured multi-year datasets obtained at 14 sites of the Aerosol Robotic Network (AERONET). We select the data with (a) large aerosol optical depth (AOD >= 0.4 at 440 nm) and (b) small Angstrom exponent (A(sub ext)<= 0.2) for retaining high accuracy and reducing interference of non-dust aerosols. The result indicates that the major fraction of high aerosol optical depth days are dominated by dust over these sites even though it varies depending on location and time. We have found that the annual mean and standard deviation of single scattering albedo, asymmetry parameter, real refractive index, and imaginary refractive index for Saharan and Arabian desert dust is 0.944 +/- 0.005, 0.752 +/- 0.014, 1.498 +/- 0.032, and 0.0024 +/- 0.0034 at 550 nm wavelength, respectively. Dust aerosol selected by this method is less absorbing than the previously reported values over these sites. The weaker absorption of dust from this study is consistent with the studies using remote sensing techniques from satellite. These results can help to constrain uncertainties in estimating global dust shortwave radiative forcing.

  18. Degeneration of aflatoxin gene clusters in Aspergillus flavus from Africa and North America.

    PubMed

    Adhikari, Bishwo N; Bandyopadhyay, Ranajit; Cotty, Peter J

    2016-12-01

    Aspergillus flavus is the most common causal agent of aflatoxin contamination of food and feed. However, aflatoxin-producing potential varies widely among A. flavus genotypes with many producing no aflatoxins. Some non-aflatoxigenic genotypes are used as biocontrol agents to prevent contamination. Aflatoxin biosynthesis genes are tightly clustered in a highly conserved order. Gene deletions and presence of single nucleotide polymorphisms (SNPs) in aflatoxin biosynthesis genes are often associated with A. flavus inability to produce aflatoxins. In order to identify mechanisms of non-aflatoxigenicity in non-aflatoxigenic genotypes of value in aflatoxin biocontrol, complete cluster sequences of 35 A. flavus genotypes from Africa and North America were analyzed. Inability of some genotypes to produce aflatoxin resulted from deletion of biosynthesis genes. In other genotypes, non-aflatoxigenicity originated from SNP formation. The process of degeneration differed across the gene cluster; genes involved in early biosynthesis stages were more likely to be deleted while genes involved in later stages displayed high frequencies of SNPs. Comparative analyses of aflatoxin gene clusters provides insight into the diversity of mechanisms of non-aflatoxigenicity in A. flavus genotypes used as biological control agents. The sequences provide resources for both diagnosis of non-aflatoxigenicity and monitoring of biocontrol genotypes during biopesticide manufacture and in the environment. PMID:27576895

  19. Parental involvement and bullying among middle-school students in North Africa.

    PubMed

    Abdirahman, H; Fleming, L C; Jacobsen, K H

    2013-03-01

    Bullying, especially in developing countries, has not been much examined, especially the influence of parents on the risk of being bullied. The aim of this study was to determine whether active parenting is associated with reduced peer victimization among middle-school students in North Africa. A secondary analysis of data from more than 13,000 middle-school students who participated in the Global School-based Student Health Survey (GSHS) in Egypt, Libya, Morocco and Tunisia between 2006 and 2008, was conducted using multiple logistic regression models. About 60% of students in Egypt and one-third of students in Libya, Morocco and Tunisia reported having been bullied in the past month. In all 4 countries, boys reported more peer victimization than girls. In Egypt, Morocco and Tunisia, students who reported that their parents checked their homework, were understanding, and knew how the student spent free time had a reduced likelihood of peer victimization but this association was not significant in Libya. Interventions for reducing bullying should consider the positive impact of involved parents. PMID:23879073

  20. Neural network and wavelets in prediction of cosmic ray variability: The North Africa as study case

    NASA Astrophysics Data System (ADS)

    Zarrouk, Neïla; Bennaceur, Raouf

    2010-04-01

    Since the Earth is permanently bombarded with energetic cosmic rays particles, cosmic ray flux has been monitored by ground based neutron monitors for decades. In this work an attempt is made to investigate the decomposition and reconstructions provided by Morlet wavelet technique, using data series of cosmic rays variabilities, then to constitute from this wavelet analysis an input data base for the neural network system with which we can then predict decomposition coefficients and all related parameters for other points. Thus the latter are used for the recomposition step in which the plots and curves describing the relative cosmic rays intensities are obtained in any points on the earth in which we do not have any information about cosmic rays intensities. Although neural network associated with wavelets are not frequently used for cosmic rays time series, they seems very suitable and are a good choice to obtain these results. In fact we have succeeded to derive a very useful tool to obtain the decomposition coefficients, the main periods for each point on the Earth and on another hand we have now a kind of virtual NM for these locations like North Africa countries, Maroc, Algeria, Tunisia, Libya and Cairo. We have found the aspect of very known 11-years cycle: T1, we have also revealed the variation type of T2 and especially T3 cycles which seem to be induced by particular Earth's phenomena.

  1. Assessment of simulated rainfall and temperature from the regional climate model REMO and future changes over Central Africa

    NASA Astrophysics Data System (ADS)

    Fotso-Nguemo, Thierry C.; Vondou, Derbetini A.; Tchawoua, Clément; Haensler, Andreas

    2016-07-01

    This work investigates spatial and temporal changes in rainfall and temperature over Central Africa, using historical and representative concentration pathways (RCP2.6, RCP4.5 and RCP8.5) of the regional climate model REMO forced by two general climate models: the Europe-wide Consortium Earth System Model (EC-Earth) and the Max Planck Institute-Earth System Model (MPI-ESM). We found that in the present period (1980-2005), the spatial distribution of rainfall is simulated with an annual spatial pattern correlation coefficient (PCC) of 0.76 for REMO driven by EC-Earth and 0.74 for REMO driven by MPI-ESM respectively when compared to CRU data. In terms of temperature, the annual PCC is 0.93 for the two REMO outputs. According to the climatology of Central Africa, we subdivided the study area into five sub-regions, we also noticed that the annual and seasonal PCC depend on the considered sub-region. For the future period (2070-2095), temperature is projected to increase following all the three scenarios. The rainfall amount is projected to decrease by up to 5 mm/day towards the end of the twenty first century under RCP8.5 scenario, and by 1-2 mm/day under RCP4.5 and RCP2.6 scenarios over Equatorial Guinea, Gabon, Congo, north-western Democratic Republic of Congo (DRC) and the Lake Victoria. Significant decrease is predicted to occur mostly in the northern part of the domain under RCP8.5 scenario. However, future rainfall over High Lands of Cameroon, Adamawa Plateau, north-eastern DRC and Atlantic Ocean is projected to increase.

  2. Relief and geology of the north polar region of the planet Venus

    NASA Technical Reports Server (NTRS)

    Kuzmin, R. O.; Burba, G. A.; Shashkina, V. P.; Bogomolov, A. F.; Zherikhin, N. V.; Skrypnik, G. I.; Kudrin, L. V.; Bergman, M. Y.; Rzhiga, O. N.; Sidorenko, A. I.

    1986-01-01

    Description of topographic features is given for the North polar region of the planet Venus. Principal geomorphic types of terrain are characterized as well as their geologic relations. Relative ages of geologic units in Venus North polar region are discussed.

  3. Greening of the Sahara - a paleo perspective on the history of water in the Middle East and North Africa

    NASA Astrophysics Data System (ADS)

    Bar-Matthews, M.

    2012-04-01

    The Middle-East, mostly at its southern edge together with North Africa, the northern edge of the Sahara Desert, are located at the boundary between high- to-mid latitude and tropical-subtropical climate systems. The geographical duality of desert adjacent to Mediterranean-type climate regions played and still plays a major role on the water availability. Thanks to the number of important paleoclimate studies that been made on accurate dating of cave speleothems in Southern Arabia and Oman (Fleitmann et al., 2011) and in the northeast Sahara, the Negev Desert Israel (Vaks et al., 2010) and the study of sapropels in Eastern and central Mediterranean (Almogi-Labin et al., 2009; Osborne et al, 2008), it is clear that the region was graced with water during peak interglacials when the African monsoon and westerly storm/rainfall systems intensified. Northward penetration of the Inter Tropical Convergence Zone over the Arabian and African continents resulted in increased discharge of the Nile River and rivers that emerged from central Sahara into the Eastern Mediterranean Sea. Correspondingly, enhanced westerly wind activity led to an increase in rainfall from Atlantic-Mediterranean sources over the entire Mediterranean basin, which even penetrated south into the north-east corner of the Sahara Desert. The Saharo-Arabian Desert became narrower and climatic "windows" opened for the dispersal of hominids and animals out of the African continent at 250-239, 210-193, 138-120, 108-98, 87-84 and 10-6.5 ka BP, with severe dry conditions in between. Greening of the Sahara Desert at these intervals is supported also by various marine and terrestrial records, such as corals, lakes, tufa deposits and archeological findings. Dry conditions prevailed in the Sahara desert during glacials. This is in contrast to the climatic conditions in the Eastern Mediterranean coastal region and the Jordan Rift Valley (Bar-Matthews et al., 2003; Lisker et al., 2010), where water was available for

  4. Switching the poles in sexual and reproductive health research: implementing a research capacity-strengthening network in West and North Africa.

    PubMed

    Dossou, Jean-Paul; Assarag, Bouchra; Delamou, Alexandre; Van der Veken, Karen; Belaid, Loubna; Ouédraogo, Moctar; Khalfallah, Sonia; Aouras, Hayet; Diadhiou, Mohamed; Fassassi, Raïmi; Delvaux, Thérèse

    2016-01-01

    Health research capacities have been improved in Africa but still remain weak as compared to other regions of the World. To strengthen these research capacities, international collaboration and networking for knowledge and capacity transfer are needed. In this commentary, we present the Network for Scientific Support in the field of Sexual and Reproductive Health in West and North Africa, its priority research topics and discuss its implementation process. Established in January 2014, the Network aims at generating human rights and gender-based research fully carried out and driven by South based institutions. It is composed of 12 institutions including the Institute of Tropical Medicine of Antwerp (Belgium) and 11 institutions from eight Francophone West and North African countries. The key areas of interest of this network are health policies analysis and health system research in family planning, HIV prevention among vulnerable groups, quality of care and breast cancers. Since it started, seventeen research proposals based on locally relevant research questions have been developed. Among the seventeen proposals, eleven have been implemented. Several research institutions enhanced linkages with local representations of international partners such as UNFPA. The network is committed to strengthening methodological research capacities and soft skills such as fundraising, advocacy and leadership. Such competencies are strongly needed for developing an effective South-based leadership in Sexual and Reproductive Health research, and for achieving the Sustainable Development Goals. PMID:27502593

  5. First Evaluation of the CCAM Aerosol Simulation over Africa: Implications for Regional Climate Modeling

    NASA Astrophysics Data System (ADS)

    Horowitz, H.; Garland, R. M.; Thatcher, M. J.; Naidoo, M.; van der Merwe, J.; Landman, W.; Engelbrecht, F.

    2015-12-01

    An accurate representation of African aerosols in climate models is needed to understand the regional and global radiative forcing and climate impacts of aerosols, at present and under future climate change. However, aerosol simulations in regional climate models for Africa have not been well-tested. Africa contains the largest single source of biomass-burning smoke aerosols and dust globally. Although aerosols are short-lived relative to greenhouse gases, black carbon in particular is estimated to be second only to carbon dioxide in contributing to warming on a global scale. Moreover, Saharan dust is exported great distances over the Atlantic Ocean, affecting nutrient transport to regions like the Amazon rainforest, which can further impact climate. Biomass burning aerosols are also exported from Africa, westward from Angola over the Atlantic Ocean and off the southeastern coast of South Africa to the Indian Ocean. Here, we perform the first extensive quantitative evaluation of the Conformal-Cubic Atmospheric Model (CCAM) aerosol simulation against monitored data, focusing on aerosol optical depth (AOD) observations over Africa. We analyze historical regional simulations for 1999 - 2012 from CCAM consistent with the experimental design of CORDEX at 50 km global horizontal resolution, through the dynamical downscaling of ERA-Interim data reanalysis data, with the CMIP5 emissions inventory (RCP8.5 scenario). CCAM has a prognostic aerosol scheme for organic carbon, black carbon, sulfate, and dust, and non-prognostic sea salt. The CCAM AOD at 550nm was compared to AOD (observed at 440nm, adjusted to 550nm with the Ångström exponent) from long-term AERONET stations across Africa. Sites strongly impacted by dust and biomass burning and with long continuous records were prioritized. In general, the model captures the monthly trends of the AERONET data. This presentation provides a basis for understanding how well aerosol particles are represented over Africa in

  6. 40 CFR 81.234 - North Central West Virginia Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 17 2010-07-01 2010-07-01 false North Central West Virginia Intrastate... Designation of Air Quality Control Regions § 81.234 North Central West Virginia Intrastate Air Quality Control Region. The North Central West Virginia Intrastate Air Quality Control Region consists of the...

  7. 40 CFR 81.234 - North Central West Virginia Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 18 2014-07-01 2014-07-01 false North Central West Virginia Intrastate... Designation of Air Quality Control Regions § 81.234 North Central West Virginia Intrastate Air Quality Control Region. The North Central West Virginia Intrastate Air Quality Control Region consists of the...

  8. 40 CFR 81.234 - North Central West Virginia Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 18 2013-07-01 2013-07-01 false North Central West Virginia Intrastate... Designation of Air Quality Control Regions § 81.234 North Central West Virginia Intrastate Air Quality Control Region. The North Central West Virginia Intrastate Air Quality Control Region consists of the...

  9. 40 CFR 81.234 - North Central West Virginia Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 18 2012-07-01 2012-07-01 false North Central West Virginia Intrastate... Designation of Air Quality Control Regions § 81.234 North Central West Virginia Intrastate Air Quality Control Region. The North Central West Virginia Intrastate Air Quality Control Region consists of the...

  10. 40 CFR 81.234 - North Central West Virginia Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 17 2011-07-01 2011-07-01 false North Central West Virginia Intrastate... Designation of Air Quality Control Regions § 81.234 North Central West Virginia Intrastate Air Quality Control Region. The North Central West Virginia Intrastate Air Quality Control Region consists of the...

  11. 40 CFR 81.250 - North Central Kansas Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 17 2010-07-01 2010-07-01 false North Central Kansas Intrastate Air... Air Quality Control Regions § 81.250 North Central Kansas Intrastate Air Quality Control Region. The North Central Kansas Intrastate Air Quality Control Region consists of the territorial area...

  12. 40 CFR 81.124 - North Central Oklahoma Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 18 2013-07-01 2013-07-01 false North Central Oklahoma Intrastate Air... Air Quality Control Regions § 81.124 North Central Oklahoma Intrastate Air Quality Control Region. The North Central Oklahoma Intrastate Air Quality Control Region consists of the territorial...

  13. 40 CFR 81.124 - North Central Oklahoma Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 17 2010-07-01 2010-07-01 false North Central Oklahoma Intrastate Air... Air Quality Control Regions § 81.124 North Central Oklahoma Intrastate Air Quality Control Region. The North Central Oklahoma Intrastate Air Quality Control Region consists of the territorial...

  14. 40 CFR 81.124 - North Central Oklahoma Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 17 2011-07-01 2011-07-01 false North Central Oklahoma Intrastate Air... Air Quality Control Regions § 81.124 North Central Oklahoma Intrastate Air Quality Control Region. The North Central Oklahoma Intrastate Air Quality Control Region consists of the territorial...

  15. 40 CFR 81.124 - North Central Oklahoma Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 18 2014-07-01 2014-07-01 false North Central Oklahoma Intrastate Air... Air Quality Control Regions § 81.124 North Central Oklahoma Intrastate Air Quality Control Region. The North Central Oklahoma Intrastate Air Quality Control Region consists of the territorial...

  16. 40 CFR 81.124 - North Central Oklahoma Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 18 2012-07-01 2012-07-01 false North Central Oklahoma Intrastate Air... Air Quality Control Regions § 81.124 North Central Oklahoma Intrastate Air Quality Control Region. The North Central Oklahoma Intrastate Air Quality Control Region consists of the territorial...

  17. 40 CFR 81.161 - North Coast Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 17 2011-07-01 2011-07-01 false North Coast Intrastate Air Quality Control Region. 81.161 Section 81.161 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Quality Control Regions § 81.161 North Coast Intrastate Air Quality Control Region. The North...

  18. 40 CFR 81.160 - North Central Coast Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 17 2011-07-01 2011-07-01 false North Central Coast Intrastate Air... Air Quality Control Regions § 81.160 North Central Coast Intrastate Air Quality Control Region. The North Central Coast Intrastate Air Quality Control Region (California) consists of the territorial...

  19. 40 CFR 81.161 - North Coast Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 18 2013-07-01 2013-07-01 false North Coast Intrastate Air Quality Control Region. 81.161 Section 81.161 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Quality Control Regions § 81.161 North Coast Intrastate Air Quality Control Region. The North...

  20. 40 CFR 81.161 - North Coast Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 18 2014-07-01 2014-07-01 false North Coast Intrastate Air Quality Control Region. 81.161 Section 81.161 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Quality Control Regions § 81.161 North Coast Intrastate Air Quality Control Region. The North...

  1. 40 CFR 81.161 - North Coast Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 18 2012-07-01 2012-07-01 false North Coast Intrastate Air Quality Control Region. 81.161 Section 81.161 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Quality Control Regions § 81.161 North Coast Intrastate Air Quality Control Region. The North...

  2. North Central Regional geologic characterization report. Volume 1. Final report

    SciTech Connect

    Not Available

    1985-08-01

    This report presents available geologic information pertinent to siting a repository for high-level nuclear waste in crystalline rock in Minnesota, Wisconsin, and the Upper Peninsula of Michigan. For each of the states within the North Central Region, information is provided on the geologic disqualifying factor and the geologic regional screening variables to be used in region-to-area screening. The geologic factor and variables include deep mines and quarries, rock mass extent, post-emplacement faulting, suspected Quaternary faulting, seismicity, rock and mineral resources, major groundwater discharge zones, groundwater resources, state of stress, thickness of rock mass, and thickness of overburden. Information is presented on age, areal extent, shape, composition, texture, degree and type of alteration, thickness, and structural features associated with each rock body or complex. Regional seismic and tectonic information is presented, including patterns of earthquake occurrence, earthquake magnitudes, horizontal ground accelerations, and vertical crustal movements. Also included are discussions of the rock and mineral deposits or mines located within or near crystalline rock bodies; groundwater resources and regional hydrology; postulated changes in climate and the associated effects; and landforms, surface processes, and surficial materials on or near the rock bodies. A discussion is also presented of the relationship between the US Department of Energy Siting Guidelines (10 CFR 960) and the geologic disqualifying factor and regional screening variables to be used in the region-to-area screening process. 43 figs., 15 tabs.

  3. Desertification, refugees and regional conflict in west Africa.

    PubMed

    Nnoli, O

    1990-06-01

    This article documents the potential for inter-state conflict in the migration of hundreds of thousands of famine refugees across international borders in West Africa. Nigeria and Ghana, for example, have to deal not only with the effects of land degradation in their northern territories but also with the influx of famine victims from Mali, Niger, Chad and Burkino Faso. These migrations put an enormous extra burden on the fragile and already overstretched social and economic infrastructures of the host countries. The construction of dams for irrigation and electricity generation in international river basins, is another cause of inter-state conflict related to land degradation. The capacity of West African states to find peaceful solutions to these problems is being undermined by the increasing impoverishment and marginalisation of their populations. A self-serving neo-colonialist governing elite is caught in the economic stranglehold of the advanced capitalist nations. While there is thus no short term solution to the problem of land degradation, immediate steps should at least be taken to give legal protection to those who are forced to cross international borders because of drought and famine. PMID:20958699

  4. Seasonal Scale Water Deficit Forecasting in East Africa and the Middle East Region Using the NMME Models Forecasts

    NASA Astrophysics Data System (ADS)

    Shukla, S.; Funk, C. C.; Zaitchik, B. F.; Narapusetty, B.; Arsenault, K. R.; Peters-Lidard, C. D.

    2015-12-01

    In this presentation we report on our ongoing efforts to provide seasonal scale water deficit forecasts in East Africa and the Middle East regions. First, we report on the skill of the seasonal climate forecasts from the North American Multimodel Ensemble (NMME) models over this region. We evaluated deterministic (anomaly correlation), categorical (the equitable threat score) and probabilistic (the ranked probabilistic skill score) skill of the NMME models forecasts over the hindcast period of 1982-2010, focusing on the primary rainy seasons of March-May (MAM), July-September (JAS) and October-December (OND). We also examined the potential predictability of the NMME models using the anomaly correlation between the ensemble mean forecasts from a given model against a single ensemble member of the same model (homogenous predictability) and rest of the models (heterogeneous predictability), and observations (forecast skill). Overall, we found precipitation forecast skill in this region to be sparse and limited (up to three month of lead) to some locations and seasons, and temperature forecast skill to be much more skillful than the precipitation forecast skill. Highest level of skill exists over equatorial East Africa (OND season) and over parts of northern Ethiopia and southern Sudan (JAS season). Categorical and probabilistic forecast skills are also higher in those regions. We found the homogeneous predictability to be greater than the forecast skill indicating potential for forecast skill improvement. In the rest of the presentation we describe implementation and evaluation of a hybrid approach (that combines statistical and dynamical approaches) of downscaling climate forecasts to improve the precipitation forecast skill in this region. For this part of the analysis we mainly focus on two of the NMME models (NASA's GMAO and NCEP's CFSv2). Past research on a hybrid approach focusing only over equatorial East Africa has shown promising results. We found that MAM

  5. Regional and Global Aspects of Aerosols in Western Africa: From Air Quality to Climate

    NASA Technical Reports Server (NTRS)

    Chin, Mian; Diehl, Thomas; Kucsera, Tom; Spinhime, Jim; Palm, Stephen; Holben, Brent; Ginoux, Paul

    2006-01-01

    Western Africa is one of the most important aerosol source regions in the world. Major aerosol sources include dust from the world's largest desert Sahara, biomass burning from the Sahel, pollution aerosols from local sources and long-range transport from Europe, and biogenic sources from vegetation. Because these sources have large seasonal variations, the aerosol composition over the western Africa changes significantly with time. These aerosols exert large influences on local air quality and regional climate. In this study, we use the Goddard Chemistry Aerosol Radiation and Transport (GOCART) model to analyze satellite lidar data from the GLAS instrument on the ICESat and the sunphotometer data from the ground-based network AERONET taken in both the wet (September - October 2003) and dry (February - March 2004) seasons over western Africa. We will quantify the seasonal variations of aerosol sources and compositions and aerosol spatial (horizontal and vertical) distributions over western Africa. We will also assess the climate impact of western African aerosols. Such studies will be applied to support the international project, Africa Monsoon Multidisciplinary Analysis (AMMA) and to analyze the AMMA data.

  6. Future water availability in North African dams simulated by high-resolution regional climate models

    NASA Astrophysics Data System (ADS)

    Tramblay, Yves; Jarlan, Lionel; Hanich, Lahoucine; Somot, Samuel

    2016-04-01

    In North Africa, the countries of Morocco, Algeria and Tunisia are already experiencing water scarcity and a strong interannual variability of precipitation. To better manage their existing water resources, several dams and reservoirs have been built on most large river catchments. The objective of this study is to provide quantitative scenarios of future changes in water availability for the 47 major dams and reservoirs catchments located in North Africa. An ensemble of regional climate models (RCM) with a spatial resolution of 12km, driven by different general circulation models (GCM), from the EuroCORDEX experiment have been considered to analyze the projected changes on temperature, precipitation and potential evapotranspiration (PET) for two scenarios (RCP4.5 and RCP8.5) and two time horizons (2040-2065 and 2065-2090). PET is estimated from RCM outputs either with the FAO-Penman-Monteith (PM) equation, requiring air temperature, relative humidity, net radiation and wind, or with the Hargreave Samani (HS) equation, requiring only air temperature. The water balance is analyzed by comparing the climatic demand and supply of water, considering that for most of these catchments groundwater storage is negligible over long time periods. Results indicated a future temperature increase for all catchments between +1.8° and +4.2°, depending on the emission scenario and the time period considered. Precipitation is projected to decrease between -14% to -27%, mainly in winter and spring, with a strong East to West gradient. PET computed from PM or HS formulas provided very similar estimates and projections, ranging between +7% to +18%. Changes in PET are mostly driven by rising temperatures and are greatest during dry summer months than for the wet winter season. Therefore the increased PET has a lower impact than declining precipitation on future water availability, which is expected to decrease by -19% to -33% on average.

  7. Combined statistical and dynamical assessment of simulated vegetation–rainfall in North Africa during the mid-Holocene*

    SciTech Connect

    Notaro, Michael; Wang, Yi; Liu, Zhengyu; Gallimore, Robert; Levis, Samuel

    2008-01-05

    A negative feedback of vegetation cover on subsequent annual precipitation is simulated for the mid-Holocene over North Africa using a fully coupled general circulation model with dynamic vegetation, FOAM-LPJ (Fast Ocean Atmosphere Model-Lund Potsdam Jena Model). By computing a vegetation feedback parameter based on lagged autocovariances, the simulated impact of North African vegetation on precipitation is statistically quantified. The feedback is also dynamically assessed through initial value ensemble experiments, in which North African grass cover is initially reduced and the climatic response analyzed. The statistical and dynamical assessments of the negative vegetation feedback agree in sign and relative magnitude for FOAM-LPJ. The negative feedback on annual precipitation largely results from a competition between bare soil evaporation and plant transpiration, with increases in the former outweighing reductions in the latter given reduced grass cover. This negative feedback weakens and eventually reverses sign over time during a transient simulation from the mid-Holocene to present. A similar, but weaker, negative feedback is identified in Community Climate System Model Version 2 (CCSM2) over North Africa for the mid-Holocene.

  8. Sources of material for 'loess' deposits at 15°N in North Africa

    NASA Astrophysics Data System (ADS)

    McLaren, Sue; Smalley, Ian; O'Hara-Dhand, Ken

    2014-05-01

    Africa is not a loess-rich continent. Lacking are the large expanses of glacial terrain and the high cold mountain regions, which would have provided the material and processes for loess deposits. African geomorphology and climatic history did not favour the formation of major loess deposits. However, within the African setting there are situations which could lead to particle formation and loess deposition. Loess deposits are made from 'large' dust (i.e. particles around 30µm). Small dust (around 3µm) is generated in large amounts in Africa, and distributed over large distances. Large dust is not generated in significant amounts in Africa, and this accounts for the relative lack of loess deposits. It is a relative lack; examination of the map of loess distribution in the World by Scheidig 1934 (still the best world loess map) shows some possible loess in Africa. In particular there is a band across the continent at around 15°N. We propose some possible sources for this material, and fit these sources into a recently revised deterministic model of loess deposit formation. And look at some exotic but possible indicators of the loessic nature of the 15°N band. Three possible material sources are: (1). The Fonta-Djalon highlands to the west of the loess band, (2). The Bodélé Depression, towards the centre of the loess band, and (3). The Ethiopian highlands to the east. There is a convenient river associated with the loess band; the Niger rises in the Fonta-Djalon region and carries material through the loess zone. The catchment of the Niger is well placed to receive large dust material from the Bodélé depression. Most Bodélé material is small dust carried away in high suspension but small amounts of large dust could be transported to the Niger catchment. Material from the Ethiopian highlands makes up the Nile silt but again some could be transported to the west to contribute to the loess band- which is a modest loess deposit. The deposit can be examined with

  9. Observed and Simulated Regional North American Vegetation Dynamics: 1982- 2005

    NASA Astrophysics Data System (ADS)

    Neigh, C. S.; Tucker, C. J.; Townshend, J. R.; Collatz, G. J.

    2006-12-01

    Normalized difference vegetation index data from the NOAA series of Advanced Very High Resolution Radiometers (AVHRR) revealed regions in North America that experienced marked increases in annual photosynthetic capacity at various times from 1982 to 2005. Inspection of these anomalous areas with Landsat, Ikonos, aerial photography, and ancillary statistical datasets revealed a range of causes: climatic influences; drought and subsequent recovery; irrigated agriculture expansion; herbivores insect outbreaks followed by logging and subsequent regeneration; and forest fires with subsequent regeneration. We describe an efficient continental monitoring system that simulates biogeochemistry dynamics to quantify changing carbon content of ecosystems.

  10. AIDS in Southern Africa: a major factor in planning for the region.

    PubMed

    Place, J L

    1990-01-01

    This article discusses the spread and impact of AIDS in Southern Africa, as well as government responses to the pandemic. A with a total of 14,325 reported AIDS cases as of September 1990, the countries the Southern Africa (Angola, Botswana, Lesotho, Malawi, Mozambique, Namibia, South Africa, Zambia, and Zimbabwe) now account for 20% of all AIDS cases in Africa. This represents an eightfold increase in just over 2 years. Because of the young age structure of the population, which in the next few years will become sexually active, experts fear rapid increases in the rate of infection. With the exception of South Africa, AIDS has struck men and women alike. The region has also witnessed a growing number of HIV-infected babies and children orphaned by the disease. Besides its cost in human lives, the spread of AIDs threatens the economic development of the region, as it effects the most productive segment of the population, and as the resources to combat the disease dwindle, while its destructive potential grows. Surveillance of the disease has proven difficult, especially among refugees and returning exiles. Government responses to the pandemic have differed. In Zambia, where President Kaunda's own son died of the disease, the government has adopted an extensive AIDS program. Kaunda has appealed for a compassionate treatment of people with AIDS. The South African response, however, has met great skepticism. Most of the AIDS cases have been among blacks and homosexuals, 2 groups that have been marginalized by society. Nonetheless, the region has seen a bright note with the formation of the Southern Africa Network of AIDS Service Organization, which is designed to promote cooperation in combating the spread of AIDS. PMID:12284198