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Sample records for africa region human

  1. Financing Vocational Training in Sub-Saharan Africa. Africa Region Human Development Series.

    ERIC Educational Resources Information Center

    Ziderman, Adrian

    This document is part of the World Bank's comprehensive study of post-basic education and training in Sub-Sahara Africa and includes findings from three short field studies conducted in South Africa, Tanzania, and Zimbawe in early 2001. Chapter titles are as follows: Executive Summary; Introduction; Conventional Patterns of Financing Training;…

  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.

  3. Regions. [Africa, Middle East].

    PubMed

    1985-03-01

    This discussion of population focuses on the regions of Africa and the Middle East. In South Africa more white women are working but fewer black women work. The overall result is that the percentage of women who work is declining. Marita de Beer, research liaison executive at the South African Advertising Research Foundation, reports that the female population grew by 31% in the past 10 years while the number of working women has grown by only 11%. Among blacks the female population rose by 36%, but the number of workers among them declined by about 1%. Married women are among the fastest growing groups of working women in South Africa. The most recent estimate of the population of Nigeria is 92 million. According to Professor Vremudia Diejomaoh, Nigeria's population will probably reach 155 million by 2000 with 33% living in urban areas. In Saudi Arabia the Pan Arab Research Center recently completed a census of retail outlets in 3 metropolitan areas: Jeddah, Riyadh, and Dammam. The types of outlets surveyed include large supermarkets, small supermarkets, groceries with and without deep freeze, tobacco shops, meat shop/delis, small cafeterias, large restaurants/hotels, cosmetics shops or perfumeries, camera stores, toy shops, pharmacies, watch and gift shop, newsstands, department store, and appliance outlets. Using the Census of Retail Outlets as a base, Pan Arab Research Center also has a new distribution audit system that will cover 500 outlets. By plotting Arab countries according to their population policies and their current growth rates, it is possible to project where the middle class will grow fastest in the Arab world. The countries that have declining growth rates and strong population programs designed to encourage lower fertility rates among women are Egypt, Tunisia, Morocco, Algeria, and Lebanon. The countries most likely to have a better per capita distribution of resources within this decade are those where governments encourage reductions in

  4. Prospects and challenges in the introduction of human papillomavirus vaccines in the extended Middle East and North Africa region.

    PubMed

    Jumaan, Aisha O; Ghanem, Soha; Taher, Jalaa; Braikat, Mhammed; Al Awaidy, Salah; Dbaibo, Ghassan S

    2013-12-30

    The development of effective and safe human papillomavirus (HPV) vaccines provides a great opportunity to prevent a devastating disease, cervical cancer, and a host of other related diseases. However, the introduction of these vaccines has been slow in the Extended Middle East and North Africa (EMENA) region. Only one country has introduced the vaccine and few countries plan HPV vaccine introduction in the coming 5 years. Several factors influence the slow uptake in the region, including financial constraints, weak infrastructure for adolescent vaccine delivery, competition with high priority vaccines, and lack of reliable data on the burden of HPV disease. Other barriers include cultural and religious sensitivities, as the vaccines are offered to prevent a sexually transmitted disease in young girls. Recommendations to enhance HPV vaccine introduction in EMENA countries include establishing a regional joint vaccine procurement program, enhancing the adolescent vaccination platform, documenting the burden of cervical cancer, strengthening local National Immunization Technical Advisory Groups and designing Information, Education and Communication material that address cultural concerns. 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 Related Diseases" Vaccine Volume 30, Supplement 5, 2012.

  5. Regional case studies--Africa.

    PubMed

    Prentice, Andrew M

    2009-01-01

    Africa is the final continent to be affected by the nutrition transition and, as elsewhere, is characterized by the paradoxical coexistence of malnutrition and obesity. Several features of the obesity epidemic in Africa mirror those in other emerging nations: it penetrates the richer nations and urban areas first with a strong urban- rural gradient; initially it affects the wealthy, but later there is a demographic switch as obesity becomes a condition more associated with poverty, and it shares many of the same drivers related to the increasing affordability of highly refined oils and carbohydrates, and a move away from subsistence farm work and towards sedentary lifestyles. Africa also has some characteristics of the obesity epidemic that stand out from other regions such as: (1) excepting some areas of the Pacific, Africa is probably the only region in which obesity (especially among women) is viewed culturally as a positive and desirable trait, leading to major gender differences in obesity rates in many countries; (2) most of Africa has very low rates of obesity in children, and to date African obesity is mostly an adult syndrome; (3) Africans seem genetically prone to higher rates of diabetes and hypertension in association with obesity than Caucasians, but seem to be relatively protected from dislipidemias; (4) the case-specific deaths and disabilities from diabetes and hypertension in Africa are very high due to the paucity of health services and the strain that the 'double burden' of disease places on health systems.

  6. 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.

  7. 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.

  8. 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…

  9. Regional Projections of Extreme Apparent Temperature Days in Africa and the Related Potential Risk to Human Health

    PubMed Central

    Garland, Rebecca M.; Matooane, Mamopeli; Engelbrecht, Francois A.; Bopape, Mary-Jane M.; Landman, Willem A.; Naidoo, Mogesh; van der Merwe, Jacobus; Wright, Caradee Y.

    2015-01-01

    Regional climate modelling was used to produce high resolution climate projections for Africa, under a “business as usual scenario”, that were translated into potential health impacts utilizing a heat index that relates apparent temperature to health impacts. The continent is projected to see increases in the number of days when health may be adversely affected by increasing maximum apparent temperatures (AT) due to climate change. Additionally, climate projections indicate that the increases in AT results in a moving of days from the less severe to the more severe Symptom Bands. The analysis of the rate of increasing temperatures assisted in identifying areas, such as the East African highlands, where health may be at increasing risk due to both large increases in the absolute number of hot days, and due to the high rate of increase. The projections described here can be used by health stakeholders in Africa to assist in the development of appropriate public health interventions to mitigate the potential health impacts from climate change. PMID:26473895

  10. Regional Projections of Extreme Apparent Temperature Days in Africa and the Related Potential Risk to Human Health.

    PubMed

    Garland, Rebecca M; Matooane, Mamopeli; Engelbrecht, Francois A; Bopape, Mary-Jane M; Landman, Willem A; Naidoo, Mogesh; Merwe, Jacobus van der; Wright, Caradee Y

    2015-10-12

    Regional climate modelling was used to produce high resolution climate projections for Africa, under a "business as usual scenario", that were translated into potential health impacts utilizing a heat index that relates apparent temperature to health impacts. The continent is projected to see increases in the number of days when health may be adversely affected by increasing maximum apparent temperatures (AT) due to climate change. Additionally, climate projections indicate that the increases in AT results in a moving of days from the less severe to the more severe Symptom Bands. The analysis of the rate of increasing temperatures assisted in identifying areas, such as the East African highlands, where health may be at increasing risk due to both large increases in the absolute number of hot days, and due to the high rate of increase. The projections described here can be used by health stakeholders in Africa to assist in the development of appropriate public health interventions to mitigate the potential health impacts from climate change.

  11. The Impact of Adult Mortality on Primary School Enrollment in Northwestern Tanzania. Africa Region Human Development Working Paper Series.

    ERIC Educational Resources Information Center

    Ainsworth, Martha; Beegle, Kathleen; Koda, Godlike

    The AIDS epidemic is making orphans out of many African children and threatens to reverse hard-won gains in raising school enrollments. The average gross primary enrollment ration (GPER) the number of children enrolled as a percent of the total number of children of school age was only 77% for Sub-Saharan Africa in 1996. The countries are hard-hit…

  12. Human origins: Out of Africa

    PubMed Central

    Tattersall, Ian

    2009-01-01

    Our species, Homo sapiens, is highly autapomorphic (uniquely derived) among hominids in the structure of its skull and postcranial skeleton. It is also sharply distinguished from other organisms by its unique symbolic mode of cognition. The fossil and archaeological records combine to show fairly clearly that our physical and cognitive attributes both first appeared in Africa, but at different times. Essentially modern bony conformation was established in that continent by the 200–150 Ka range (a dating in good agreement with dates for the origin of H. sapiens derived from modern molecular diversity). The event concerned was apparently short-term because it is essentially unanticipated in the fossil record. In contrast, the first convincing stirrings of symbolic behavior are not currently detectable until (possibly well) after 100 Ka. The radical reorganization of gene expression that underwrote the distinctive physical appearance of H. sapiens was probably also responsible for the neural substrate that permits symbolic cognition. This exaptively acquired potential lay unexploited until it was “discovered” via a cultural stimulus, plausibly the invention of language. Modern humans appear to have definitively exited Africa to populate the rest of the globe only after both their physical and cognitive peculiarities had been acquired within that continent. PMID:19805256

  13. Minerals Strategic Impact on Regional Stability in Africa

    DTIC Science & Technology

    2007-03-30

    USAWC STRATEGY RESEARCH PROJECT MINERALS STRATEGIC IMPACT ON REGIONAL STABILITY IN AFRICA by Colonel Lee E...3. DATES COVERED 00-00-2006 to 00-00-2007 4. TITLE AND SUBTITLE Minerals Strategic Impact on Regional Stability in Africa 5a. CONTRACT NUMBER...Lee E. Hansen TITLE: Minerals Strategic Impact on Regional Stability in Africa FORMAT: Strategy Research Project DATE: 30 March 2007

  14. The first modern human dispersals across Africa.

    PubMed

    Rito, Teresa; Richards, Martin B; Fernandes, Verónica; Alshamali, Farida; Cerny, Viktor; Pereira, Luísa; Soares, Pedro

    2013-01-01

    The emergence of more refined chronologies for climate change and archaeology in prehistoric Africa, and for the evolution of human mitochondrial DNA (mtDNA), now make it feasible to test more sophisticated models of early modern human dispersals suggested by mtDNA distributions. Here we have generated 42 novel whole-mtDNA genomes belonging to haplogroup L0, the most divergent clade in the maternal line of descent, and analysed them alongside the growing database of African lineages belonging to L0's sister clade, L1'6. We propose that the last common ancestor of modern human mtDNAs (carried by "mitochondrial Eve") possibly arose in central Africa ~180 ka, at a time of low population size. By ~130 ka two distinct groups of anatomically modern humans co-existed in Africa: broadly, the ancestors of many modern-day Khoe and San populations in the south and a second central/eastern African group that includes the ancestors of most extant worldwide populations. Early modern human dispersals correlate with climate changes, particularly the tropical African "megadroughts" of MIS 5 (marine isotope stage 5, 135-75 ka) which paradoxically may have facilitated expansions in central and eastern Africa, ultimately triggering the dispersal out of Africa of people carrying haplogroup L3 ~60 ka. Two south to east migrations are discernible within haplogroup LO. One, between 120 and 75 ka, represents the first unambiguous long-range modern human dispersal detected by mtDNA and might have allowed the dispersal of several markers of modernity. A second one, within the last 20 ka signalled by L0d, may have been responsible for the spread of southern click-consonant languages to eastern Africa, contrary to the view that these eastern examples constitute relicts of an ancient, much wider distribution.

  15. 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

  16. 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

  17. Dialogue on Climate, Water, Energy and Human Security in Africa

    DTIC Science & Technology

    2014-07-01

    DIALOGUE ON CLIMATE,  WATER , ENERGY AND HUMAN SECURITY  IN AFRICA  The Africa Center for Security Studies, US Africa Command, and the US Army Corps of...organizations  responsible  for managing  water   resources  in  these  basins/regions  on  a  transboundry basis, and  to  launch more  robust co‐operation...COVERED 00-00-2014 to 00-00-2014 4. TITLE AND SUBTITLE Dialogue on Climate, Water , Energy and Human Security in Africa 5a. CONTRACT NUMBER W911NF

  18. Africa's Famine: The Human Dimension.

    ERIC Educational Resources Information Center

    Raloff, Janet

    1985-01-01

    Human activities are believed to have had major impact on disasters which have previously been called "natural." Overcultivation, overgrazing, and deforestation are used to illustrate how many African nations have become weakened and impoverished. Programs directed toward economic development are essential for overcoming these problems.…

  19. 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…

  20. Mitochondrial footprints of human expansions in Africa.

    PubMed Central

    Watson, E; Forster, P; Richards, M; Bandelt, H J

    1997-01-01

    mtDNA studies support an African origin for modern Eurasians, but expansion events within Africa have not previously been investigated. We have therefore analyzed 407 mtDNA control-region sequences from 13 African ethnic groups. A number of sequences (13%) were highly divergent and coalesced on the "mitochondrial Eve" in Africans. The remaining sequences also ultimately coalesced on this sequence but fell into four major clusters whose starlike phylogenies testify to demographic expansions. The oldest of these African expansions dates to approximately 60,000-80,000 years ago. Eurasian sequences are derived from essentially one sequence within this ancient cluster, even though a diverse mitochondrial pool was present in Africa at the time. PMID:9326335

  1. Regional Initiatives in Support of Surveillance in East Africa: The East Africa Integrated Disease Surveillance Network (EAIDSNet) Experience

    PubMed Central

    Ope, Maurice; Sonoiya, Stanley; Kariuki, James; Mboera, Leonard E.G.; Gandham, Ramana N.V.; Schneidman, Miriam; Kimura, Mwihaki

    2013-01-01

    The East African Integrated Disease Surveillance Network (EAIDSNet) was formed in response to a growing frequency of cross-border malaria outbreaks in the 1990s and a growing recognition that fragmented disease interventions, coupled with weak laboratory capacity, were making it difficult to respond in a timely manner to the outbreaks of malaria and other infectious diseases. The East Africa Community (EAC) partner states, with financial support from the Rockefeller Foundation, established EAIDSNet in 2000 to develop and strengthen the communication channels necessary for integrated cross-border disease surveillance and control efforts. The objective of this paper is to review the regional EAIDSNet initiative and highlight achievements and challenges in its implementation. Major accomplishments of EAIDSNet include influencing the establishment of a Department of Health within the EAC Secretariat to support a regional health agenda; successfully completing a regional field simulation exercise in pandemic influenza preparedness; and piloting a web-based portal for linking animal and human health disease surveillance. The strategic direction of EAIDSNet was shaped, in part, by lessons learned following a visit to the more established Mekong Basin Disease Surveillance (MBDS) regional network. Looking to the future, EAIDSNet is collaborating with the East, Central and Southern Africa Health Community (ECSA-HC), EAC partner states, and the World Health Organization to implement the World Bank-funded East Africa Public Health Laboratory Networking Project (EAPHLNP). The network has also begun lobbying East African countries for funding to support EAIDSNet activities. PMID:23362409

  2. The evolution of human genetic and phenotypic variation in Africa.

    PubMed

    Campbell, Michael C; Tishkoff, Sarah A

    2010-02-23

    Africa is the birthplace of modern humans, and is the source of the geographic expansion of ancestral populations into other regions of the world. Indigenous Africans are characterized by high levels of genetic diversity within and between populations. The pattern of genetic variation in these populations has been shaped by demographic events occurring over the last 200,000 years. The dramatic variation in climate, diet, and exposure to infectious disease across the continent has also resulted in novel genetic and phenotypic adaptations in extant Africans. This review summarizes some recent advances in our understanding of the demographic history and selective pressures that have influenced levels and patterns of diversity in African populations.

  3. 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.

  4. Regional paleogeographic evolution of West Africa: Implications for hydrocarbon exploration

    SciTech Connect

    Hempton, M.R. )

    1993-11-01

    New paleogeographic reconstructions of west African continental margins provide a regional framework to contrast differences in hydrocarbon habitat and tectonostratigraphic style. The framework consists of five regional provinces: (1) northwest Africa margin from Mauritania to Sierra Leone, (2) transform margin from Libera 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 along three rift systems during the Late Triassic to the Holocene. 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 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 (Barremian) 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.

  5. Impacts of Irrigation Development on Regional Rainfall in Africa

    NASA Astrophysics Data System (ADS)

    Alter, R. E.; IM, E. S.; Eltahir, E. A. B.

    2014-12-01

    Potential modification of regional rainfall by large-scale cropland irrigation has been investigated in several regions of the world. In particular, regional climate simulations over West Africa indicate that hypothetical large-scale irrigation schemes reduce rainfall over the irrigated areas but enhance rainfall remotely. However, these theoretical results cannot be substantiated without direct comparison to observations. We therefore conducted two complementary analyses over an actual, large-scale irrigation scheme in Africa: numerical simulations using a regional climate model, and observational analyses using several surface-based and satellite-derived datasets. For the observational analyses, we analyzed spatial and temporal patterns of both rainfall and air temperature in and around the irrigated area. For the numerical simulations, we examined multiple variables that contribute to an improved understanding of the mechanistic pathway between irrigation and rainfall modification. The results of both the simulations and observational analysis will be presented.

  6. Impacts of Irrigation Development on Regional Rainfall in Africa

    NASA Astrophysics Data System (ADS)

    Alter, R. E.; IM, E. S.; Eltahir, E. A. B.

    2015-12-01

    Potential modification of regional rainfall by large-scale cropland irrigation has been investigated in several regions of the world. In particular, regional climate simulations over West Africa indicate that hypothetical large-scale irrigation schemes reduce rainfall over the irrigated areas but enhance rainfall remotely. However, these theoretical results cannot be substantiated without direct comparison to observations. We therefore conducted two complementary analyses over an actual, large-scale irrigation scheme in Africa: numerical simulations using a regional climate model, and observational analyses using several surface-based and satellite-derived datasets. For the observational analyses, we analyzed spatial and temporal patterns of both rainfall and air temperature in and around the irrigated area. For the numerical simulations, we examined multiple variables that contribute to an improved understanding of the mechanistic pathway between irrigation and rainfall modification. The results of both the simulations and observational analysis will be presented.

  7. Regional stratigraphy and petroleum geology, North Africa-Middle East

    SciTech Connect

    Peterson, J.A. )

    1991-03-01

    The North Africa-Middle East petroleum provinces are part of the broad sedimentary platform that occupied the northern and northeastern borders of the African-Arabian craton adjacent to the ancestral Hercynian (late Paleozoic) and subsequent Tethyan-Alpine oceans. Carbonate-clastic-evaporite sediments of infra-Cambrian through Holocene age were cyclically deposited in a relatively continuous belt around the eastern and northern borders of the craton, mainly on a broad, shallow-water platform adjacent to the proto-Tethys and Tethys seaway. The Paleozoic section reaches a substantial thickness in the subsurface of the Middle East and in northern Africa adjacent to the Mediterranean Sea, but all or part of it is absent because of nondeposition or erosion over much of the region. Post-Paleozoic deposition was more or less continuous across the entire craton border region in the Middle East and along the northern border of the Sahara platform in North Africa and in Somalia and eastern Ethiopia. Similar marine and associated sedimentary rock facies are present in all of these regions, although paleotectonic-stratigraphic interrelationships and continental paleolatitude positions have greatly affected petroleum generation and accumulation in the specific provinces along the craton border. A series of regional stratigraphic-sedimentary environment, and continental position, layer maps illustrates the relative influence of these factors through geologic time with respect to the relationship between petroleum reservoirs, source rocks, and confining rock facies.

  8. 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.

  9. Human ecology and behaviour in malaria control in tropical Africa

    PubMed Central

    MacCormack, C. P.

    1984-01-01

    Since about 250 BC, human modification of African environments has created increasingly favourable breeding conditions for Anopheles gambiae. Subsequent adaptations to the increased malaria risk are briefly described and reference is made to Macdonald's mathematical model for the disease. Since values for the variables in that model are high in tropical Africa, there is little possibility that simple, inexpensive, self-help primary health care initiatives can control malaria in the region. However, in combination with more substantial public health initiatives, simple primary health care activities might be done by communities to (1) prevent mosquitos from feeding on people, (2) prevent or reduce mosquito breeding, (3) destroy adult mosquitos, and (4) eliminate malaria parasites from human hosts. Lay methods of protection and self-care are examined and some topics for further research are indicated. Culturally appropriate health education methods are also suggested. PMID:6335685

  10. Africa's neglected area of human resources for health research - the way forward.

    PubMed

    Ijsselmuiden, C; Marais, D L; Becerra-Posada, F; Ghannem, H

    2012-03-07

    Building the skills for doing, managing and delivering health research is essential for every country's development. Yet, human resources for health research (HRHR) are seldom considered in Africa and elsewhere. Africa's health research capacity has grown considerably, with potential to increase this growth. However, a systemic way of defining, co-ordinating and growing the HRHR needed to support health systems development is missing. Reviewing the status of HRHR in Africa, we assert that it consists of uncoordinated, small-scale activities, primarily driven from outside Africa. We present examples of ongoing HRHR capacity building initiatives in Africa. There is no overarching framework, strategy or body for African countries to optimise research support and capacity in HRHR. A simple model is presented to help countries plan and strategise for a comprehensive approach to research capacity strengthening. Everyone engaged with global, regional and national research for health enterprises must proactively address human resource planning for health research in Africa. Unless this is made explicit in global and national agendas, Africa will remain only an interested spectator in the decisions, prioritisation, funding allocations, conduct and interpretation, and in the institutional, economic and social benefits of health research, rather than owning and driving its own health research agendas.

  11. Gene flow from North Africa contributes to differential human genetic diversity in southern Europe

    PubMed Central

    Botigué, Laura R.; Henn, Brenna M.; Gravel, Simon; Maples, Brian K.; Gignoux, Christopher R.; Corona, Erik; Atzmon, Gil; Burns, Edward; Ostrer, Harry; Flores, Carlos; Bertranpetit, Jaume; Comas, David; Bustamante, Carlos D.

    2013-01-01

    Human genetic diversity in southern Europe is higher than in other regions of the continent. This difference has been attributed to postglacial expansions, the demic diffusion of agriculture from the Near East, and gene flow from Africa. Using SNP data from 2,099 individuals in 43 populations, we show that estimates of recent shared ancestry between Europe and Africa are substantially increased when gene flow from North Africans, rather than Sub-Saharan Africans, is considered. The gradient of North African ancestry accounts for previous observations of low levels of sharing with Sub-Saharan Africa and is independent of recent gene flow from the Near East. The source of genetic diversity in southern Europe has important biomedical implications; we find that most disease risk alleles from genome-wide association studies follow expected patterns of divergence between Europe and North Africa, with the principal exception of multiple sclerosis. PMID:23733930

  12. Gene flow from North Africa contributes to differential human genetic diversity in southern Europe.

    PubMed

    Botigué, Laura R; Henn, Brenna M; Gravel, Simon; Maples, Brian K; Gignoux, Christopher R; Corona, Erik; Atzmon, Gil; Burns, Edward; Ostrer, Harry; Flores, Carlos; Bertranpetit, Jaume; Comas, David; Bustamante, Carlos D

    2013-07-16

    Human genetic diversity in southern Europe is higher than in other regions of the continent. This difference has been attributed to postglacial expansions, the demic diffusion of agriculture from the Near East, and gene flow from Africa. Using SNP data from 2,099 individuals in 43 populations, we show that estimates of recent shared ancestry between Europe and Africa are substantially increased when gene flow from North Africans, rather than Sub-Saharan Africans, is considered. The gradient of North African ancestry accounts for previous observations of low levels of sharing with Sub-Saharan Africa and is independent of recent gene flow from the Near East. The source of genetic diversity in southern Europe has important biomedical implications; we find that most disease risk alleles from genome-wide association studies follow expected patterns of divergence between Europe and North Africa, with the principal exception of multiple sclerosis.

  13. The origin and dispersion of human parasitic diseases in the old world (Africa, Europe and Madagascar).

    PubMed

    Nozais, Jean-Pierre

    2003-01-01

    The ancestors of present-day man (Homo sapiens sapiens) appeared in East Africa some three and a half million years ago (Australopithecs), and then migrated to Europe, Asia, and later to the Americas, thus beginning the differentiation process. The passage from nomadic to sedentary life took place in the Middle East in around 8000 BC. Wars, spontaneous migrations and forced migrations (slave trade) led to enormous mixtures of populations in Europe and Africa and favoured the spread of numerous parasitic diseases with specific strains according to geographic area. The three human plasmodia (Plasmodium falciparum, P. vivax, and P. malariae) were imported from Africa into the Mediterranean region with the first human migrations, but it was the Neolithic revolution (sedentarisation, irrigation, population increase) which brought about actual foci for malaria. The reservoir for Leishmania infantum and L. donovani--the dog--has been domesticated for thousands of years. Wild rodents as reservoirs of L. major have also long been in contact with man and probably were imported from tropical Africa across the Sahara. L. tropica, by contrast, followed the migrations of man, its only reservoir. L. infantum and L. donovani spread with man and his dogs from West Africa. Likewise, for thousands of years, the dog has played an important role in the spread and the endemic character of hydatidosis through sheep (in Europe and North Africa) and dromadary (in the Sahara and North Africa). Schistosoma haematobium and S. mansoni have existed since prehistoric times in populations living in or passing through the Sahara. These populations then transported them to countries of Northern Africa where the specific, intermediary hosts were already present. Madagascar was inhabited by populations of Indonesian origin who imported lymphatic filariosis across the Indian Ocean (possibly of African origin since the Indonesian sailors had spent time on the African coast before reaching Madagascar

  14. Lost Horizons: The Humanities in South Africa (Part 1)

    ERIC Educational Resources Information Center

    Vale, Peter

    2008-01-01

    Politics chartered the development of the Humanities in South Africa. Under the apartheid system three separate traditions--English-speaking, Afrikaner and Homeland--co-existed, albeit uneasily, in separate institutional forms. As apartheid crumbled in the 1980s, the Humanities, by drawing the three traditions together, established a growing voice…

  15. First Detection of Human Dirofilariasis in South Africa

    PubMed Central

    Moodley, Krishnee; Govind, Chetna N.; Peer, Abdool K.C.; van der Westhuizen, Marissa; Parbhoo, Dharmesh; Sun, Lisa Ming; du Plessis, Desiree C.; Frean, John A.

    2015-01-01

    Humans are occasionally inadvertently infected with dirofilariae, the zoonotic nematodes. We report two cases of human dirofilariasis in South Africa, an area apparently non-endemic for this infection. Dirofilariasis is frequently misdiagnosed, so increased awareness of this entity in areas that are non-endemic is essential for prevention of inappropriate investigations and invasive therapy. PMID:25874068

  16. Wetlands of South Africa: Hydrology and Human Use

    NASA Astrophysics Data System (ADS)

    Price, J. S.; Grundling, P.; Grundling, A.

    2009-05-01

    South Africa has a relatively dry climate (average 479 mm/y), and consequently wetlands are sparse covering 10-12% of the land surface, but locally extremely important hydrologically, ecologically and as a resource for human use. Given the climate, peatlands occur only where strong and sustained groundwater discharge occurs - either from regional-scale hydrogeological formations or from more localized aquifers such as coastal dunes, etc., and comprise 8-10% of South African wetlands. Elsewhere, the seasonal variation in precipitation typically results in ephemeral wetlands (without peat). In either case the perennial or seasonal availability of fresh-water is a focus of ecological activity and often of human interaction. Human use of wetlands includes water abstraction, grazing and harvesting of materials for building and handicrafts , often done in a sustainable manner. Other activities include totally unsustainable peat extraction and partly sustainable cultivation. Activities adjacent to wetlands including mining, timber plantations and groundwater exploitation for mining, commercial agriculture and urban water needs can also profoundly affect their water supply. Disturbances upstream or within wetlands can cause severe erosion and gullying. From 30 - 50% of wetlands have been lost due to landuse changes in their drainage basins or in the wetland itself. Ecohydrological feedback to even relatively modest disturbance of these systems can elicit a cycle of destructive and ongoing degradation. Wetland management requires a good understanding of the ecohydrological and landscape factors that support wetlands, proactive measures for restoration, and sensitivity to the needs of poverty-stricken users of wetland resources.

  17. Africa: the human dimensions of high fertility.

    PubMed

    Foly, A

    1985-09-01

    This article describes the impact of rapid population growth and high fertility on the lives of rural families in West Africa. Population pressures have exacerbated environmental problems and made daily activities such as food production, child care, and access to water and firewood more difficult. Crowded, impoverished homes lead young people to enter into early marriages and childbearing. The lack of fertility control results in premature weaning, close child spacing, and malnutrition. Population problems further contribute to economic problems and social dislocation; symptomatic of the breakdown of the family system is the rapid increase in premarital adolescent pregnancies. Growing need for firewood has led to deforestation, which in turn has resulted in soil erosion, declining soil fertility, and poor harvests. Although women in West Africa express a desire for access to the basic necessities of life (clean water, an adequate food supply, money for children's school fees), they generally fail to perceive the connection between population pressure and decreased food production, inadequate income, and physical exhaustion. Solutions to the problem of overpopulation cannot be imposed from the outside; they must be part of the framework of African women's lives and thoughts. It is necessary to pay attention to desires of these women and their thoughts about how changes can be achieved. If problems are approached from the perspective of those most affected, connections will eventually be discovered between food production, income, family planning, and family health.

  18. 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.

  19. 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

  20. 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

  1. 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.

  2. "Eve" in Africa: Human Evolution Meets Molecular Biology.

    ERIC Educational Resources Information Center

    Seager, Robert D.

    1990-01-01

    Presented is a discussion of recent evidence on the evolution of human forms on earth gathered and evaluated using mitochondrial DNA techniques. Theories regarding the possibility that a common female ancestor existed in Africa about 200,000 years ago are discussed. A list of teaching aids is provided. (CW)

  3. The 'medical humanities' in health sciences education in South Africa.

    PubMed

    Reid, S

    2014-02-01

    A new masters-level course, 'Medicine and the Arts" will be offered in 2014 at the University of Cape Town, setting a precedent for interdisciplinary education in the field of medical humanities in South Africa. The humanities and social sciences have always been an implicit part of undergraduate and postgraduate education in the health sciences, but increasingly they are becoming an explicit and essential component of the curriculum, as the importance of graduate attributes and outcomes in the workplace is acknowledged. Traditionally, the medical humanities have included medical ethics, history, literature and anthropology. Less prominent in the literature has been the engagement with medicine of the disciplines of sociology, politics, philosophy, linguistics, education, and law, as well as the creative and expressive arts. The development of the medical humanities in education and research in South Africa is set to expand over the next few years, and it looks as if it will be an exciting inter-disciplinary journey.

  4. 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…

  5. The WASCAL regional climate simulations for West Africa - how to add value to existing climate projections

    NASA Astrophysics Data System (ADS)

    Arnault, J.; Heinzeller, D.; Klein, C.; Dieng, D.; Smiatek, G.; Bliefernicht, J.; Sylla, M. B.; Kunstmann, H.

    2015-12-01

    With climate change being one of the most severe challenges to rural Africa in the 21st century, West Africa is facing an urgent need to develop effective adaptation and mitigation measures to protect its constantly growing population. WASCAL (West African Science Service Center on Climate Change and Adapted Land Use) is a large-scale research-focused program designed to enhance the resilience of human and environmental systems to climate change and increased variability. An integral part of its climate services is the provisioning of a new set of high resolution, ensemble-based regional climate change scenarios for the region of West Africa. In this contribution, we present the overall concept of the WASCAL regional climate projections and provide information on the dissemination of the data. We discuss the model performance over the validation period for two of the three regional climate models employed, the Weather Research & Forecasting Tool (WRF) and the Consortium for Small-scale Modeling Model COSMO in Climate Mode (COSMO-CLM), and give details about a novel precipitation database used to verify the models. Particular attention is paid to the representation of the dynamics of the West African Summer Monsoon and to the added value of our high resolution models over existing data sets. We further present results on the climate change signal obtained from the WRF model runs for the periods 2020-2050 and 2070-2100 and compare them to current state-of-the-art projections from the CORDEX project. As an example, the figure shows the different climate change signals obtained for the total annual rainfall with respect to the 1980-2010 mean (WRF-E: WASCAL 12km high-resolution run MPI-ESM + WRFV3.5.1, CORDEX-E: 50km medium-resolution run MPI-ESM + RCA4, CORDEX-G: 50km medium-resolution run GFDL-ESM + RCA4).

  6. 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

  7. Genome-wide and paternal diversity reveal a recent origin of human populations in North Africa.

    PubMed

    Fadhlaoui-Zid, Karima; Haber, Marc; 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.

  8. Impacts of Climate Change/Variability and Human Activities on Contemporary Vegetation Productivity across Africa

    NASA Astrophysics Data System (ADS)

    Ugbaje, S. U.; Odeh, I. A.; Bishop, T.

    2015-12-01

    Vegetation productivity is increasingly being impacted upon by climate change/variability and anthropogenic activities, especially in developing countries, where many livelihoods depend on the natural resource base. Despite these impacts, the individual and combined roles of climate and anthropogenic factors on vegetation dynamics have rarely been quantified in many ecosystems and regions of the world. This paper analyzes recent trend in vegetation productivity across Africa and quantified the relative roles of climate change/variability and human activities in driving this trend over 2000-2014 using net primary productivity (NPP) as an indicator. The relative roles of these factors to vegetation productivity change were quantified by comparing the trend slope (p<0.1) and total change in interannual actual NPP (NPPA), potential NPP (NPPP), and human appropriated NPP (NPPH). NPP significantly increased across Africa relative to NPP decline, though the extent of NPP decline is also quite appreciable. Whereas estimated NPP declined by 207 Tg C over 140 X 104 km of land area, vegetation productivity was estimated to improve by 1415 Tg C over 786 X 104 km of land area. NPP improvement is largely concentrated in equatorial and northern hemispheric Africa, while subequatorial Africa exhibited the most NPP decline. Generally, anthropogenic activities dominated climate change/variability in improving or degrading vegetation productivity. Of the estimated total NPP gained over the study period, 32.6, 8.8, and 58.6 % were due to individual human, climate and combined impacts respectively. The contributions of the factors to NPP decline in the same order are: 50.7, 16.0 and 33.3 %. The Central Africa region is where human activities had the greatest impact on NPP improvement; whereas the Sahel and the coastlines of west northern Africa are areas associated with the greatest influence of climate-driven NPP gain. Areas with humans dominating NPP degradation include eastern

  9. Post-Gondwanan continental sedimentaiton, Limpopo region, southeastern Africa

    NASA Astrophysics Data System (ADS)

    Botha, G. A.; De Wit, M. C. J.

    1996-08-01

    The post-Karoo age sedimentary succession known formerly as the Malvernia Formation, is currently termed the Malonga Formation, 'Formaçao de Sena', 'Formaçao de Singuédeze/Elefantes' and Gona-re-Zhou Plateau Beds in the Limpopo Basin region where South Africa, Mozambique and Zimbabwe have common borders. These rocks represent continental, taphrogenic sedimentation on the eastern margin of the emergent African continent after the breakup of Gondwana. The wide occurrence of this system along the northern Lebombo mountains and within the tectonically active Limpopo and Zambezi valleys, suggests the existence of a peidmont landsurface comprising coalesced alluvial fans and major fluvial channel/floodplain systems close to the continental margin during the Late Mesozoic to Early Cainozoic era. Sedimentation followed the long period of eustatic uplift associated with Karoo vulcanicity and the extensional tectonics and rifting along the continental margin and within the proto-Limpopo and Zambezi valleys. The Malonga Formation exposed near Pafuri in the extreme NW of South Africa shows an eastward lithological change from homogeneous, poorly-sorted, thinly-bedded sandstones and conglomerates, deposited by sheetflood action, to a sequence of fining-upward units comprising clast-supported pebble to boulder grade conglomerate and overlying planar bedded silt and sand, deposited in fluvial channel and floodplain environments. The homogeneous, silty succession exposed in the Olifants River valley, east of the Lebombo mountains in Mozambique, possibly represents the distal reaches of this system. Calcareous palaeosols developed within the sedimentary units suggest periodic geomorphic stability on the broad alluvial plain. Further north in southeastern Zimbabwe, laterally continuous depositional units comprising thinly-bedded, poorly-sorted, matrix-supported conglomerate, interbedded with very coarse-grained sandstone, is consistent with deposition on an alluvial fan complex

  10. Change in land water storage in the East Africa region inferred from GRACE and altimetry data.

    NASA Astrophysics Data System (ADS)

    Becker, M.; Cazenave, A.

    2008-12-01

    Drought can be regarded as one of the most damaging of natural disasters in human, environmental, and economic terms. It occurs as a result of extremes in climate that are driven by natural variability but may be exacerbated or dampened by anthropogenic influences. In East Africa rainfall exhibits a great spatial and temporal variability. Such events have impact on the water budget of this region. But water use and more generally anthropogenic forcing also affect regional hydrology. In this study, we investigate water storage change (surface and ground) using in synergy satellite radar altimetry, GRACE satellite gravity and other data to quantify recent change in surface waters and total land storage in East Africa over the recent years. Water levels of most East African lakes display significant decrease since the strong ENSO event of 1997- 1998. GRACE data available since 2002 also show decrease in total water storage over this region. The volume of water stored within lakes and reservoirs is a sensitive proxy for precipitation and may be used to study the combined impact of climate change and water-resource management. We also combine GRACE, altimetry and precipitation data sets to explore the relative contributions of the source term to the seasonal and interannual hydrological balance of this area and its link with the western Indian Ocean thermal change

  11. Private sector, human resources and health franchising in Africa.

    PubMed

    Prata, Ndola; Montagu, Dominic; Jefferys, Emma

    2005-04-01

    In much of the developing world, private health care providers and pharmacies are the most important sources of medicine and medical care and yet these providers are frequently not considered in planning for public health. This paper presents the available evidence, by socioeconomic status, on which strata of society benefit from publicly provided care and which strata use private health care. Using data from The World Bank's Health Nutrition and Population Poverty Thematic Reports on 22 countries in Africa, an assessment was made of the use of public and private health services, by asset quintile groups, for treatment of diarrhoea and acute respiratory infections, proxies for publicly subsidized services. The evidence and theory on using franchise networks to supplement government programmes in the delivery of public health services was assessed. Examples from health franchises in Africa and Asia are provided to illustrate the potential for franchise systems to leverage private providers and so increase delivery-point availability for public-benefit services. We argue that based on the established demand for private medical services in Africa, these providers should be included in future planning on human resources for public health. Having explored the range of systems that have been tested for working with private providers, from contracting to vouchers to behavioural change and provider education, we conclude that franchising has the greatest potential for integration into large-scale programmes in Africa to address critical illnesses of public health importance.

  12. Private sector, human resources and health franchising in Africa.

    PubMed Central

    Prata, Ndola; Montagu, Dominic; Jefferys, Emma

    2005-01-01

    In much of the developing world, private health care providers and pharmacies are the most important sources of medicine and medical care and yet these providers are frequently not considered in planning for public health. This paper presents the available evidence, by socioeconomic status, on which strata of society benefit from publicly provided care and which strata use private health care. Using data from The World Bank's Health Nutrition and Population Poverty Thematic Reports on 22 countries in Africa, an assessment was made of the use of public and private health services, by asset quintile groups, for treatment of diarrhoea and acute respiratory infections, proxies for publicly subsidized services. The evidence and theory on using franchise networks to supplement government programmes in the delivery of public health services was assessed. Examples from health franchises in Africa and Asia are provided to illustrate the potential for franchise systems to leverage private providers and so increase delivery-point availability for public-benefit services. We argue that based on the established demand for private medical services in Africa, these providers should be included in future planning on human resources for public health. Having explored the range of systems that have been tested for working with private providers, from contracting to vouchers to behavioural change and provider education, we conclude that franchising has the greatest potential for integration into large-scale programmes in Africa to address critical illnesses of public health importance. PMID:15868018

  13. Archaeological shellfish size and later human evolution in Africa.

    PubMed

    Klein, Richard G; Steele, Teresa E

    2013-07-02

    Approximately 50 ka, one or more subgroups of modern humans expanded from Africa to populate the rest of the world. Significant behavioral change accompanied this expansion, and archaeologists commonly seek its roots in the African Middle Stone Age (MSA; ∼200 to ∼50 ka). Easily recognizable art objects and "jewelry" become common only in sites that postdate the MSA in Africa and Eurasia, but some MSA sites contain possible precursors, especially including abstractly incised fragments of ocher and perforated shells interpreted as beads. These proposed art objects have convinced most specialists that MSA people were behaviorally (cognitively) modern, and many argue that population growth explains the appearance of art in the MSA and its post-MSA florescence. The average size of rocky intertidal gastropod species in MSA and later coastal middens allows a test of this idea, because smaller size implies more intense collection, and more intense collection is most readily attributed to growth in the number of human collectors. Here we demonstrate that economically important Cape turban shells and limpets from MSA layers along the south and west coasts of South Africa are consistently and significantly larger than turban shells and limpets in succeeding Later Stone Age (LSA) layers that formed under equivalent environmental conditions. We conclude that whatever cognitive capacity precocious MSA artifacts imply, it was not associated with human population growth. MSA populations remained consistently small by LSA standards, and a substantial increase in population size is obvious only near the MSA/LSA transition, when it is dramatically reflected in the Out-of-Africa expansion.

  14. Archaeological shellfish size and later human evolution in Africa

    PubMed Central

    Klein, Richard G.; Steele, Teresa E.

    2013-01-01

    Approximately 50 ka, one or more subgroups of modern humans expanded from Africa to populate the rest of the world. Significant behavioral change accompanied this expansion, and archaeologists commonly seek its roots in the African Middle Stone Age (MSA; ∼200 to ∼50 ka). Easily recognizable art objects and “jewelry” become common only in sites that postdate the MSA in Africa and Eurasia, but some MSA sites contain possible precursors, especially including abstractly incised fragments of ocher and perforated shells interpreted as beads. These proposed art objects have convinced most specialists that MSA people were behaviorally (cognitively) modern, and many argue that population growth explains the appearance of art in the MSA and its post-MSA florescence. The average size of rocky intertidal gastropod species in MSA and later coastal middens allows a test of this idea, because smaller size implies more intense collection, and more intense collection is most readily attributed to growth in the number of human collectors. Here we demonstrate that economically important Cape turban shells and limpets from MSA layers along the south and west coasts of South Africa are consistently and significantly larger than turban shells and limpets in succeeding Later Stone Age (LSA) layers that formed under equivalent environmental conditions. We conclude that whatever cognitive capacity precocious MSA artifacts imply, it was not associated with human population growth. MSA populations remained consistently small by LSA standards, and a substantial increase in population size is obvious only near the MSA/LSA transition, when it is dramatically reflected in the Out-of-Africa expansion. PMID:23776248

  15. 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…

  16. 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…

  17. Impact of human schistosomiasis in sub-Saharan Africa.

    PubMed

    Adenowo, Abiola Fatimah; Oyinloye, Babatunji Emmanuel; Ogunyinka, Bolajoko Idiat; Kappo, Abidemi Paul

    2015-01-01

    Schistosomiasis, a neglected tropical disease of poverty ranks second among the most widespread parasitic disease in various nations in sub-Saharan Africa. Neglected tropical diseases are causes of about 534,000 deaths annually in sub-Saharan Africa and an estimated 57 million disability-adjusted life-years are lost annually due to the neglected tropical diseases. The neglected tropical diseases exert great health, social and financial burden on economies of households and governments. Schistosomiasis has profound negative effects on child development, outcome of pregnancy, and agricultural productivity, thus a key reason why the "bottom 500 million" inhabitants of sub-Saharan Africa continue to live in poverty. In 2008, 17.5 million people were treated globally for schistosomiasis, 11.7 million of those treated were from sub-Saharan Africa. This enervating disease has been successfully eradicated in Japan, as well as in Tunisia. Morocco and some Caribbean Island countries have made significant progress on control and management of this disease. Brazil, China and Egypt are taking steps towards elimination of the disease, while most sub-Saharan countries are still groaning under the burden of the disease. Various factors are responsible for the continuous and persistent transmission of schistosomiasis in sub-Saharan Africa. These include climatic changes and global warming, proximity to water bodies, irrigation and dam construction as well as socio-economic factors such as occupational activities and poverty. The morbidity and mortality caused by this disease cannot be overemphasized. This review is an exposition of human schistosomiasis as it affects the inhabitants of various communities in sub-Sahara African countries. It is hoped this will bring a re-awakening towards efforts to combat this impoverishing disease in terms of vaccines development, alternative drug design, as well as new point-of-care diagnostics.

  18. Out of Africa: origins of the Taenia tapeworms in humans.

    PubMed

    Hoberg, E P; Alkire, N L; de Queiroz, A; Jones, A

    2001-04-22

    Phylogenetic and divergence date analyses indicate that the occurrence of Taenia tapeworms in humans pre-dates the development of agriculture, animal husbandry and domestication of cattle (Bos spp.) or swine (Sus scrofa). Taeniid tapeworms in Africa twice independently colonized hominids and the genus Homo prior to the origin of modern humans. Dietary and behavioural shifts, from herbivory to scavenging and carnivory, as early Homo entered the carnivore guild in the Pliocene/Pleistocene, were drivers for host switching by tapeworms to hominids from carnivores including hyaenids and felids. Parasitological data provide a unique means of elucidating the historical ecology, foraging behaviour and food habits of hominids during the diversification of Homo spp.

  19. Africa: the next frontier for human disease gene discovery?

    PubMed

    Ramsay, Michèle; Tiemessen, Caroline T; Choudhury, Ananyo; Soodyall, Himla

    2011-10-15

    The populations of Africa harbour the greatest human genetic diversity following an evolutionary history tracing its beginnings on the continent to time before the emergence of Homo sapiens. Signatures of selection are detectable as responses to ancient environments and cultural practices, modulated by more recent events including infectious epidemics, migrations, admixture and, of course, chance. The age of high-throughput biology is not passing Africa by. African-based cohort studies and networks with an African footprint are ideal springboards for disease-related genetic and genomic studies. Initiatives like HapMap, the 1000 Genomes Project, MalariaGEN, the INDEPTH network and Human Heredity and Health in Africa are catalysts to exploring African genetic diversity and its role in the spectrum from health to disease. The challenges are abundant in dissecting biological questions in the light of linguistic, cultural, geographic and political boundaries and their respective roles in shaping health-related profiles. Will studies based on African populations lead to a new wave of discovery of genetic contributors to disease?

  20. Human Dispersal Out of Africa: A Lasting Debate

    PubMed Central

    López, Saioa; van Dorp, Lucy; Hellenthal, Garrett

    2015-01-01

    Unraveling the first migrations of anatomically modern humans out of Africa has invoked great interest among researchers from a wide range of disciplines. Available fossil, archeological, and climatic data offer many hypotheses, and as such genetics, with the advent of genome-wide genotyping and sequencing techniques and an increase in the availability of ancient samples, offers another important tool for testing theories relating to our own history. In this review, we report the ongoing debates regarding how and when our ancestors left Africa, how many waves of dispersal there were and what geographical routes were taken. We explore the validity of each, using current genetic literature coupled with some of the key archeological findings. PMID:27127403

  1. Mosaic maternal ancestry in the Great Lakes region of East Africa.

    PubMed

    Gomes, Verónica; Pala, Maria; Salas, Antonio; Álvarez-Iglesias, Vanesa; Amorim, António; Gómez-Carballa, Alberto; Carracedo, Ángel; Clarke, Douglas J; Hill, Catherine; Mormina, Maru; Shaw, Marie-Anne; Dunne, David W; Pereira, Rui; Pereira, Vânia; Prata, Maria João; Sánchez-Diz, Paula; Rito, Teresa; Soares, Pedro; Gusmão, Leonor; Richards, Martin B

    2015-09-01

    The Great Lakes lie within a region of East Africa with very high human genetic diversity, home of many ethno-linguistic groups usually assumed to be the product of a small number of major dispersals. However, our knowledge of these dispersals relies primarily on the inferences of historical, linguistics and oral traditions, with attempts to match up the archaeological evidence where possible. This is an obvious area to which archaeogenetics can contribute, yet Uganda, at the heart of these developments, has not been studied for mitochondrial DNA (mtDNA) variation. Here, we compare mtDNA lineages at this putative genetic crossroads across 409 representatives of the major language groups: Bantu speakers and Eastern and Western Nilotic speakers. We show that Uganda harbours one of the highest mtDNA diversities within and between linguistic groups, with the various groups significantly differentiated from each other. Despite an inferred linguistic origin in South Sudan, the data from the two Nilotic-speaking groups point to a much more complex history, involving not only possible dispersals from Sudan and the Horn but also large-scale assimilation of autochthonous lineages within East Africa and even Uganda itself. The Eastern Nilotic group also carries signals characteristic of West-Central Africa, primarily due to Bantu influence, whereas a much stronger signal in the Western Nilotic group suggests direct West-Central African ancestry. Bantu speakers share lineages with both Nilotic groups, and also harbour East African lineages not found in Western Nilotic speakers, likely due to assimilating indigenous populations since arriving in the region ~3000 years ago.

  2. Human immunodeficiency virus infection and AIDS in east Africa: challenges and possibilities for prevention and control.

    PubMed

    Mhalu, F S; Lyamuya, E

    1996-01-01

    Human immunodeficiency infection and AIDS are a major recent microbial infection in east Africa with serious health and socioeconomic impacts in the region. At present HIV infection and AIDS account for more than 50% of adult medical admissions into some of the national and provincial hospitals as well as for 10-15% of paediatric admissions. AIDS is also at present the commonest cause of death among those aged 15-45 years. Tuberculosis, a closely associated disease to HIV infection, has increased more than three fold in some countries in the region. The prevalence of HIV infection currently ranges from 10-30% among adults in urban areas and from less than 1% to 25% in adults in rural areas; since this prevalence is still rising, the full impact of the AIDS problem in east Africa is yet to be realised. This is different from the situation in many developed countries where AIDS is no longer a priority health issue and where peak prevalences of the infection have been reached. The differences in HIV prevalences between east Africa and developed countries are due to poverty, ignorance, high prevalence of other STDs and associated cultural and traditional practices which prevail and facilitate HIV transmission in the region. While more than 80% of HIV infection in east Africa is transmitted through heterosexual intercourse, 5-15% of cases are perinatally transmitted and the remaining cases are transmitted through blood and blood products. While a lot of scientific advances have been made in immunopathology of AIDS, diagnostics and in social behavioural studies, we are still a long way towards getting curative therapy and or effective preventive vaccines. Recent discovery that use of zidovudine can significantly reduce perinatal HIV transmission is an additional breakthrough. While knowledge and tools for preventing HIV transmission are available in the world, prospects for AIDS control in east Africa appear gloomy unless major efforts are made in the reduction of

  3. 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

  4. Human Responses to Climate Variability: The Case of South Africa

    NASA Astrophysics Data System (ADS)

    Oppenheimer, M.; Licker, R.; Mastrorillo, M.; Bohra-Mishra, P.; Estes, L. D.; Cai, R.

    2014-12-01

    Climate variability has been associated with a range of societal and individual outcomes including migration, violent conflict, changes in labor productivity, and health impacts. Some of these may be direct responses to changes in mean temperature or precipitation or extreme events, such as displacement of human populations by tropical cyclones. Others may be mediated by a variety of biological, social, or ecological factors such as migration in response to long-term changes in crops yields. Research is beginning to elucidate and distinguish the many channels through which climate variability may influence human behavior (ranging from the individual to the collective, societal level) in order to better understand how to improve resilience in the face of current variability as well as future climate change. Using a variety of data sets from South Africa, we show how climate variability has influenced internal (within country) migration in recent history. We focus on South Africa as it is a country with high levels of internal migration and dramatic temperature and precipitation changes projected for the 21st century. High poverty rates and significant levels of rain-fed, smallholder agriculture leave large portions of South Africa's population base vulnerable to future climate change. In this study, we utilize two complementary statistical models - one micro-level model, driven by individual and household level survey data, and one macro-level model, driven by national census statistics. In both models, we consider the effect of climate on migration both directly (with gridded climate reanalysis data) and indirectly (with agricultural production statistics). With our historical analyses of climate variability, we gain insights into how the migration decisions of South Africans may be influenced by future climate change. We also offer perspective on the utility of micro and macro level approaches in the study of climate change and human migration.

  5. Evolution of human-driven fire regimes in Africa.

    PubMed

    Archibald, Sally; Staver, A Carla; Levin, Simon A

    2012-01-17

    Human ability to manipulate fire and the landscape has increased over evolutionary time, but the impact of this on fire regimes and consequences for biodiversity and biogeochemistry are hotly debated. Reconstructing historical changes in human-derived fire regimes empirically is challenging, but information is available on the timing of key human innovations and on current human impacts on fire; here we incorporate this knowledge into a spatially explicit fire propagation model. We explore how changes in population density, the ability to create fire, and the expansion of agropastoralism altered the extent and seasonal distribution of fire as modern humans arose and spread through Africa. Much emphasis has been placed on the positive effect of population density on ignition frequency, but our model suggests this is less important than changes in fire spread and connectivity that would have occurred as humans learned to light fires in the dry season and to transform the landscape through grazing and cultivation. Different landscapes show different limitations; we show that substantial human impacts on burned area would only have started ~4,000 B.P. in open landscapes, whereas they could have altered fire regimes in closed/dissected landscapes by ~40,000 B.P. Dry season fires have been the norm for the past 200-300 ky across all landscapes. The annual area burned in Africa probably peaked between 4 and 40 kya. These results agree with recent paleocarbon studies that suggest that the biomass burned today is less than in the recent past in subtropical countries.

  6. Poverty and human immunodeficiency virus in children: a view from the Western Cape, South Africa.

    PubMed

    Marais, Barend Jacobus; Esser, Monika; Godwin, Sarah; Rabie, Helena; Cotton, Mark Fredric

    2008-01-01

    Sub-Saharan Africa is the region affected worst by human immunodeficiency virus (HIV), with the most southern countries, including Botswana, Zimbabwe, Swaziland, and South Africa, carrying the highest disease burden. This geographic distribution represents a complex interaction among virological, political, social, cultural, and economic forces. In South Africa the HIV epidemic is seemingly unchecked, with 18% of the adult population infected. Although South Africa is a mid-developed country, there is a large chasm between the wealthy and the poor, with many living in moderate to extreme poverty. Poverty creates conditions that fuel the HIV epidemic while HIV exacerbates the multiple interlinking causes of poverty. Children are the most vulnerable members of society, severely affected by all components of the poverty cycle. Although improved health education and access to care will alleviate many problems, sustainable poverty alleviation should form an essential component of the response to AIDS. The formulation of the United Nations Millennium Developmental Goals is an important step in the right direction, but global and local political commitment is essential for success.

  7. A Spring Forward for Human Evolution in East Africa?

    NASA Astrophysics Data System (ADS)

    Cuthbert, M. O.; Ashley, G. M.

    2014-12-01

    The current consensus is that humans evolved in Africa and then migrated in waves to other parts of the world starting as early as 2 Ma. The climate was both cooling and drying. One of the major unknowns connected with human survival in this climatically turbulent environment is the availability of resources, particularly water. A growing body of geological evidence shows an association between springs, stone tools and hominin fossils at a number of sites in the East African Rift System (EARS) during a critical period for hominin evolution (from 1.8 Ma). The springs may have been vulnerable to climate variability, thus the role that groundwater availability may have played in human evolution and migration to other continents is not known. Using palaeogeological reconstruction and groundwater modelling of the paleo-catchment of one such EARS site, Olduvai Gorge (3°S), we show how spring discharge was likely linked to climate variability of annual to Milankovitch cycle timescales. Under decadal to centennial timescales, spring flow would have been relatively invariant providing good water resource resilience through long droughts. For multi-millennial periods, modelled spring flows lag groundwater recharge by 100s to 1000 years. Our results show how groundwater would have provided 'drought proof' water supply and habitats during arid phases as potable surface water from rivers or lakes became increasingly scarce. Localized groundwater systems are likely to have been widespread within the EARS providing refugia and intense competition during dry periods. Thus, springs and associated wetlands may have been important factors in natural selection and evolution, as well as a vital resource during dispersal within and out of Africa. While further exploration is needed to test the geographical extent of groundwater use by early humans, we propose that groundwater flow systems produced in the EARS played a significant role in the evolution and dispersal of early humans.

  8. Evidence for henipavirus spillover into human populations in Africa.

    PubMed

    Pernet, Olivier; Schneider, Bradley S; Beaty, Shannon M; LeBreton, Matthew; Yun, Tatyana E; Park, Arnold; Zachariah, Trevor T; Bowden, Thomas A; Hitchens, Peta; Ramirez, Christina M; Daszak, Peter; Mazet, Jonna; Freiberg, Alexander N; Wolfe, Nathan D; Lee, Benhur

    2014-11-18

    Zoonotic transmission of lethal henipaviruses (HNVs) from their natural fruit bat reservoirs to humans has only been reported in Australia and South/Southeast Asia. However, a recent study discovered numerous HNV clades in African bat samples. To determine the potential for HNV spillover events among humans in Africa, here we examine well-curated sets of bat (Eidolon helvum, n = 44) and human (n = 497) serum samples from Cameroon for Nipah virus (NiV) cross-neutralizing antibodies (NiV-X-Nabs). Using a vesicular stomatitis virus (VSV)-based pseudoparticle seroneutralization assay, we detect NiV-X-Nabs in 48% and 3-4% of the bat and human samples, respectively. Seropositive human samples are found almost exclusively in individuals who reported butchering bats for bushmeat. Seropositive human sera also neutralize Hendra virus and Gh-M74a (an African HNV) pseudoparticles, as well as live NiV. Butchering bat meat and living in areas undergoing deforestation are the most significant risk factors associated with seropositivity. Evidence for HNV spillover events warrants increased surveillance efforts.

  9. Lassa fever in West Africa: evidence for an expanded region of endemicity.

    PubMed

    Sogoba, N; Feldmann, H; Safronetz, D

    2012-09-01

    Lassa virus (LASV) is endemic in Sierra Leone, Guinea and Liberia (known as the Mano River region) and Nigeria and Lassa fever cases from these countries are being reported annually. Recent investigations have found evidence for an expanded endemicity zone between the two known Lassa endemic regions indicating that LASV is more widely distributed throughout the Tropical Wooded Savanna ecozone in West Africa.

  10. 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…

  11. Revolution and Journalism Higher Education in the Middle East/North Africa Region

    ERIC Educational Resources Information Center

    Schafer, Shaun T.

    2012-01-01

    The disruptions brought by the Arab Spring revolutions in the Middle East/North Africa (MENA) region in 2010-2011 created a series of personal and professional challenges for those involved in higher education in journalism in the region. This research uses narrative inquiry to examine the impact revolution had on a group of educators in the MENA…

  12. First vaccine designed for Africa cleared for testing in humans.

    PubMed

    2000-07-24

    During the International AIDS Conference in Durban, South Africa, the International AIDS Vaccine Initiative (IAVI) announced that a DNA vaccine based on HIV subtype A has been approved for testing in humans. This vaccine, designed specifically for Africa, has been noted to have a very good chance of stimulating cellular immune responses to HIV. Extensive studies on sex workers in Nairobi found that, despite frequent exposure to HIV, a small minority of these women has resisted infection over many years. In addition, research has also suggested that white blood cells activated by the DNA vaccine can destroy virus-infected cells. Coinciding with the news was the release of the Scientific Blueprint 2000, a global strategic research and development agenda from IAVI. This report concluded that developing an effective AIDS vaccine in the shortest possible time will require a widening of the vaccine pipeline, compressed timeliness for clinical trials, greater focus on the needs of developing countries and more funding. To this effect, the report calls for the implementation of several initiatives for the realization of the scientific program of IAVI.

  13. Occurrence of aflatoxins in human foodstuffs in South Africa

    SciTech Connect

    Loetter, L.H.; Kroehm, H.J.

    1988-02-01

    Aflatoxins are toxic metabolites of Aspergillus spp and have been reported as contaminants in a number of foodstuffs, namely corn, rice, peanuts, and cereals. In the Republic of South Africa, aflatoxin levels in human foodstuffs are limited to a maximum of 10 ..mu..g/kg for the total and 5 ..mu..g/kg for aflatoxin B/sub 1/. During 1985 and 1986, samples of sorghum beer, sorghum cereal, peanuts, peanut butter and maize meal were purchased from supermarkets in Johannesburg and analyzed for aflatoxins. A total of 414 samples were analyzed during the survey. In 1985, roughly a third of the samples were contaminated with aflatoxins, with no levels in excess of the legal limit. In 1986 the percentage of contaminated samples rose significantly, but the levels of contamination remained low, with only one sample exceeding the legal maximum.

  14. Human immunodeficiency virus and migrant labor in South Africa.

    PubMed

    Jochelson, K; Mothibeli, M; Leger, J P

    1991-01-01

    The authors investigate the impact of the migrant labor system on heterosexual relationships on South African mines and assess the implications for the future transmission of human immunodeficiency virus (HIV) infection. The migrant labor system has created a market for prostitution in mining towns and geographic networks of relationships within and between urban and rural communities. A section of the migrant workforce and a group of women dependent on prostitution for economic support appear especially vulnerable to contracting HIV infection since they are involved in multiple sexual encounters with different, changing partners, usually without condom protection. Furthermore, sexually transmitted disease morbidity is extensive in the general and mineworker populations. Historically, migration facilitated the transmission of sexually transmitted diseases and may act similarly for HIV. Problems of combating the HIV epidemic in South Africa are discussed.

  15. Human rabies deaths in Africa: breaking the cycle of indifference.

    PubMed

    Dodet, Betty; Tejiokem, Mathurin C; Aguemon, Abdou-Rahman; Bourhy, Hervé

    2015-01-01

    The current outbreak of Ebola virus disease has mobilized the international community against this deadly disease. However, rabies, another deadly disease, is greatly affecting the African continent, with an estimated 25 000 deaths every year. And yet, the disease can be prevented by a vaccine, if necessary with immunoglobulin, even when administered after exposure to the rabies virus. Rabies victims die because of neglect and ignorance, because they are not aware of these life-saving biologicals, or because they cannot access them or do not have the money to pay for them. Breaking the cycle of indifference of rabies deaths in humans in Africa should be a priority of governments, international organizations and all stakeholders involved.

  16. Regional Climate Change Impact on Agricultural Land Use in West Africa

    NASA Astrophysics Data System (ADS)

    Ahmed, K. F.; Wang, G.; You, L.

    2014-12-01

    Agriculture is a key element of the human-induced land use land cover change (LULCC) that is influenced by climate and can potentially influence regional climate. Temperature and precipitation directly impact the crop yield (by controlling photosynthesis, respiration and other physiological processes) that then affects agricultural land use pattern. In feedback, the resulting changes in land use and land cover play an important role to determine the direction and magnitude of global, regional and local climate change by altering Earth's radiative equilibrium. The assessment of future agricultural land use is, therefore, of great importance in climate change study. In this study, we develop a prototype land use projection model and, using this model, project the changes to land use pattern and future land cover map accounting for climate-induced yield changes for major crops in West Africa. Among the inputs to the land use projection model are crop yield changes simulated by the crop model DSSAT, driven with the climate forcing data from the regional climate model RegCM4.3.4-CLM4.5, which features a projected decrease of future mean crop yield and increase of inter-annual variability. Another input to the land use projection model is the projected changes of food demand in the future. In a so-called "dumb-farmer scenario" without any adaptation, the combined effect of decrease in crop yield and increase in food demand will lead to a significant increase in agricultural land use in future years accompanied by a decrease in forest and grass area. Human adaptation through land use optimization in an effort to minimize agricultural expansion is found to have little impact on the overall areas of agricultural land use. While the choice of the General Circulation Model (GCM) to derive initial and boundary conditions for the regional climate model can be a source of uncertainty in projecting the future LULCC, results from sensitivity experiments indicate that the changes

  17. International migration and sustainable human development in eastern and southern Africa.

    PubMed

    Oucho, J O

    1995-01-01

    International migration in eastern and southern Africa (ESA) is rarely addressed in population and development policies or regional organizations, and regional organizations must in the articulation of sustainable shared development identify the role of international migration. Poor quality data on international migration hampers analysis. Sustainable, shared, and human development within the region are subregional issues. Permanent migration is characterized among ESA countries as increasing demographic ethnic pluralism that may result in redrawing of territorial boundaries and further population movement. Portuguese and Arab settlement and integration in eastern areas resulted in coexistence, while European immigration to South Africa resulted in racial segregation. Modern colonial settlement and the aftermath of political conflict resulted in independent countries after the 1960s and outmigration of nonAfrican groups. Much of the labor migration in ESA is unskilled workers moving to South African mining regions. Labor migration to Zimbabwe and Zambia declined after the 1960s. The formation of the Common Market for ESA and the potential merger with the Preferential Trade Area and South African Development Community is a key approach to integration of migration into regional cooperation and shared development. Refugee movements create the most problems. Prior to 1992 ESA countries accounted for 83.4% of refugees, particularly in Mozambique, Ethiopia, and Somalia. Some countries blame poor economic performance on the deluge of refugees. Illegal migration is currently detected because of the required work permits, but the adoption of the Common Market would obscure this phenomenon. Human development is affected most by migrations related to drought, labor migration to strong economic areas, and return migration. The Inter-Governmental Authority on Drought and Development needs to become more active and establish better policies on nomadic and refugee movements and

  18. Impact of climate change upon vector born diseases in Europe and Africa using ENSEMBLES Regional Climate Models

    NASA Astrophysics Data System (ADS)

    Caminade, Cyril; Morse, Andy

    2010-05-01

    Climate variability is an important component in determining the incidence of a number of diseases with significant human/animal health and socioeconomic impacts. The most important diseases affecting health are vector-borne, such as malaria, Rift Valley Fever and including those that are tick borne, with over 3 billion of the world population at risk. Malaria alone is responsible for at least one million deaths annually, with 80% of malaria deaths occurring in sub-Saharan Africa. The climate has a large impact upon the incidence of vector-borne diseases; directly via the development rates and survival of both the pathogen and the vector, and indirectly through changes in the environmental conditions. A large ensemble of regional climate model simulations has been produced within the ENSEMBLES project framework for both the European and African continent. This work will present recent progress in human and animal disease modelling, based on high resolution climate observations and regional climate simulations. Preliminary results will be given as an illustration, including the impact of climate change upon bluetongue (disease affecting the cattle) over Europe and upon malaria and Rift Valley Fever over Africa. Malaria scenarios based on RCM ensemble simulations have been produced for West Africa. These simulations have been carried out using the Liverpool Malaria Model. Future projections highlight that the malaria incidence decreases at the northern edge of the Sahel and that the epidemic belt is shifted southward in autumn. This could lead to significant public health problems in the future as the demography is expected to dramatically rise over Africa for the 21st century.

  19. Ecosystem variability and early human habitats in eastern Africa

    PubMed Central

    Magill, Clayton R.; Ashley, Gail M.; Freeman, Katherine H.

    2013-01-01

    The role of savannas during the course of early human evolution has been debated for nearly a century, in part because of difficulties in characterizing local ecosystems from fossil and sediment records. Here, we present high-resolution lipid biomarker and isotopic signatures for organic matter preserved in lake sediments at Olduvai Gorge during a key juncture in human evolution about 2.0 Ma—the emergence and dispersal of Homo erectus (sensu lato). Using published data for modern plants and soils, we construct a framework for ecological interpretations of stable carbon-isotope compositions (expressed as δ13C values) of lipid biomarkers from ancient plants. Within this framework, δ13C values for sedimentary leaf lipids and total organic carbon from Olduvai Gorge indicate recurrent ecosystem variations, where open C4 grasslands abruptly transitioned to closed C3 forests within several hundreds to thousands of years. Carbon-isotopic signatures correlate most strongly with Earth’s orbital geometry (precession), and tropical sea-surface temperatures are significant secondary predictors in partial regression analyses. The scale and pace of repeated ecosystem variations at Olduvai Gorge contrast with long-held views of directional or stepwise aridification and grassland expansion in eastern Africa during the early Pleistocene and provide a local perspective on environmental hypotheses of human evolution. PMID:23267092

  20. 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

  1. Regional-scale climate-variability synchrony of cholera epidemics in West Africa

    PubMed Central

    Constantin de Magny, Guillaume; Guégan, Jean-François; Petit, Michel; Cazelles, Bernard

    2007-01-01

    Background The relationship between cholera and climate was explored in Africa, the continent with the most reported cases, by analyzing monthly 20-year cholera time series for five coastal adjoining West African countries: Côte d'Ivoire, Ghana, Togo, Benin and Nigeria. Methods We used wavelet analyses and derived methods because these are useful mathematical tools to provide information on the evolution of the periodic component over time and allow quantification of non-stationary associations between time series. Results The temporal variability of cholera incidence exhibits an interannual component, and a significant synchrony in cholera epidemics is highlighted at the end of the 1980's. This observed synchrony across countries, even if transient through time, is also coherent with both the local variability of rainfall and the global climate variability quantified by the Indian Oscillation Index. Conclusion Results of this study suggest that large and regional scale climate variability influence both the temporal dynamics and the spatial synchrony of cholera epidemics in human populations in the Gulf of Guinea, as has been described for two other tropical regions of the world, western South America and Bangladesh. PMID:17371602

  2. Why did modern human populations disperse from Africa ca. 60,000 years ago? A new model

    PubMed Central

    Mellars, Paul

    2006-01-01

    Recent research has provided increasing support for the origins of anatomically and genetically “modern” human populations in Africa between 150,000 and 200,000 years ago, followed by a major dispersal of these populations to both Asia and Europe sometime after ca. 65,000 before present (B.P.). However, the central question of why it took these populations ≈100,000 years to disperse from Africa to other regions of the world has never been clearly resolved. It is suggested here that the answer may lie partly in the results of recent DNA studies of present-day African populations, combined with a spate of new archaeological discoveries in Africa. Studies of both the mitochondrial DNA (mtDNA) mismatch patterns in modern African populations and related mtDNA lineage-analysis patterns point to a major demographic expansion centered broadly within the time range from 80,000 to 60,000 B.P., probably deriving from a small geographical region of Africa. Recent archaeological discoveries in southern and eastern Africa suggest that, at approximately the same time, there was a major increase in the complexity of the technological, economic, social, and cognitive behavior of certain African groups, which could have led to a major demographic expansion of these groups in competition with other, adjacent groups. It is suggested that this complex of behavioral changes (possibly triggered by the rapid environmental changes around the transition from oxygen isotope stage 5 to stage 4) could have led not only to the expansion of the L2 and L3 mitochondrial lineages over the whole of Africa but also to the ensuing dispersal of these modern populations over most regions of Asia, Australasia, and Europe, and their replacement (with or without interbreeding) of the preceding “archaic” populations in these regions. PMID:16772383

  3. 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.

  4. Climatic and Human Influence on Tropical Forest Degradation in West Africa

    NASA Astrophysics Data System (ADS)

    Liu, Z., Sr.; Wimberly, M. C.; Dwomoh, F. K.

    2015-12-01

    The Upper Guinean Forests of West Africa encompass one of most fragmented and endangered tropical forest ecosystems on earth. However, relatively little is known about the extent and causes of forest degradation in this heavily human affected region. We used the tasseled cap wetness (TCW) index to detect forest degradation using dry-season imagery from 2001 to 2015. TCW was calculated from MODIS (or Moderate Resolution Imaging Spectroradiometer) Nadir BRDF-Adjusted Reflectance (NBAR) at 500 meter resolution. The TCW index was compared with field data and high-resolution imagery and was found to have a strong relationship with different level of forest degradation, with lower TCW index values indicating higher levels of degradation. Mann-Kendall tests were used to detect the monotonic decreases in TCW index. Results indicated that about 12.9% of tropical forest in West Africa has been degraded during past 15 years, and most of these areas were located in isolated forest patches and on the periphery of intact forest. The boosted regression tree (BRT) method was then used to assess the influence of climate and human influence on forest degradation. BRT analysis indicated that climatic variations, human activities, and their interactions were important contributors to forest degradation. Major drivers of forest degradation included distance to cropland, rainfall trend, and rate of population growth.. Our results show that times series of coarse-resolution MODIS imagery can be used for broad-scale assessment of tropical forest degradation, and human activities need to be taken into account when assessing potential forest responses to climate change in this region.

  5. Climate Change in Africa: Impacts and Effects on the Inhabitants of the Lake Chad Region.

    NASA Astrophysics Data System (ADS)

    Abubakar, B.; Tahir, S. M.; Olisa, O.

    2009-05-01

    The Department of Energy and Climate Change defined climate as the average weather experienced over a long period. This includes temperature, wind and rainfall patterns. The climate of the Earth is not static, and has changed many times in response to a variety of natural causes. Due to human activities in emmiting green house gases has resulted the Earth to get warmed by 0.74°C over the last hundred years. Around 0.4°C of this warming has occurred since the 1970s. Climate is now one of the major phenomenon threatening lives and humanity in general since the beginning of industrial revolution. Climate exerts a profound influence on the lives of poor populations in the Lake Chad region of Africa who depend on fishing and crop cultivation for livelihood and sustenance, who are unprotected against climate-related diseases, who lacked secure access to water and food and who are vulnerable to hydro meteorological hazard. The effects of climate change on the study area are many and include diminishing resources and conflicts over the available limited water resources. The Lake Chad region is a fragile area with high climate variability and extremes of weather. As this inland water is used for domestic and agricultural purposes, salt mining, as well as transportation by Nigerians, Nigeriens, Chadian and Cameroonians, it is an area of trans-boundary water conflicts. This paper examines the part played by climate change in the decline of fishery resources and livelihood activities in the Lake Chad region. Data from field studies, structured interview and secondary sources show that fish catches and livelihood activities have declined tremendously in recent times due to several factors including overexploitation and increasing demands on the aquatic resources. Findings from the study show that droughty periods have resulted in the reduction of open lake water surface from about 25,000 km2 in 1973 to less than 2,000 km2 in the 1990s. This has led to the diminishing aquatic

  6. The Burden of Human Papillomavirus Infections and Related Diseases in Sub-Saharan Africa

    PubMed Central

    De Vuyst, Hugo; Alemany, Laia; Lacey, Charles; Chibwesha, Carla J.; Sahasrabuddhe, Vikrant; Banura, Cecily; Denny, Lynette; Parham, Groesbeck P.

    2014-01-01

    Despite the scarcity of high quality cancer registries and lack of reliable mortality data, it is clear that human papillomavirus (HPV)-associated diseases, particularly cervical cancer, are major causes of morbidity and mortality in sub-Saharan Africa (SSA). Cervical cancer incidence rates in SSA are the highest in the world and the disease is the most common cause of cancer death among women in the region. The high incidence of cervical cancer is a consequence of the inability of most countries to either initiate or sustain cervical cancer prevention services. In addition, it appears that the prevalence of HPV in women with normal cytology is higher than in more developed areas of the world, at an average of 24%. There is, however, significant regional variation in SSA, with the highest incidence of HPV infection and cervical cancer found in Eastern and Western Africa. It is expected that, due to aging and growth of the population, but also to lack of access to appropriate prevention services and the concomitant human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) epidemic, cervical cancer incidence and mortality rates in SSA will rise over the next 20 years. HPV16 and 18 are the most common genotypes in cervical cancer in SSA, although other carcinogenic HPV types, such as HPV45 and 35, are also relatively more frequent compared with other world regions. Data on other HPV-related anogenital cancers including those of the vulva, vagina, anus, and penis, are limited. Genital warts are common and associated with HPV types 6 and 11. HIV infection increases incidence and prevalence of all HPV-associated diseases. Sociocultural determinants of HPV-related disease, as well as the impact of forces that result in social destabilization, demand further study. Strategies to reduce the excessive burden of HPV-related diseases in SSA include age-appropriate prophylactic HPV vaccination, cervical cancer prevention services for women of the reproductive

  7. 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.

  8. 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.

  9. 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

  10. Regional nitrogen budget of the Lake Victoria Basin, East Africa: syntheses, uncertainties and perspectives

    NASA Astrophysics Data System (ADS)

    Zhou, Minghua; Brandt, Patric; Pelster, David; Rufino, Mariana C.; Robinson, Timothy; Butterbach-Bahl, Klaus

    2014-10-01

    Using the net anthropogenic nitrogen input (NANI) approach we estimated the N budget for the Lake Victoria Basin in East Africa. The NANI of the basin ranged from 887 to 3008 kg N km-2 yr-1 (mean: 1827 kg N km-2 yr-1) for the period 1995-2000. The net nitrogen release at basin level is due primarily to livestock and human consumption of feed and foods, contributing between 69% and 85%. Atmospheric oxidized N deposition contributed approximately 14% to the NANI of the Lake Victoria Basin, while either synthetic N fertilizer imports or biological N fixations only contributed less than 6% to the regional NANI. Due to the low N imports of feed and food products (<20 kg N km-2 yr-1), nitrogen release to the watershed must be derived from the mining of soil N stocks. The fraction of riverine N export to Lake Victoria accounted for 16%, which is much lower than for watersheds located in Europe and USA (25%). A significant reduction of the uncertainty of our N budget estimate for Lake Victoria Basin would be possible if better data on livestock systems and riverine N export were available. Our study indicates that at present soil N mining is the main source of nitrogen in the Lake Victoria Basin. Thus, sustainable N management requires increasing agricultural N inputs to guarantee food security and rehabilitation and protection of soils to minimize environmental costs. Moreover, to reduce N pollution of the lake, improving management of human and animal wastes needs to be carefully considered in future.

  11. Projection of temperature and heat waves for Africa with an ensemble of CORDEX Regional Climate Models

    NASA Astrophysics Data System (ADS)

    Dosio, Alessandro

    2016-09-01

    The most severe effects of global warning will be related to the frequency and severity of extreme events. We provide an analysis of projections of temperature and related extreme events for Africa based on a large ensemble of Regional Climate Models from the COordinated Regional climate Downscaling EXperiment (CORDEX). Results are presented not only by means of widely used indices but also with a recently developed Heat Wave Magnitude Index-daily (HWMId), which takes into account both heat wave duration and intensity. Results show that under RCP8.5, warming of more than 3.5 °C is projected in JFM over most of the continent, whereas in JAS temperatures over large part of Northern Africa, the Sahara and the Arabian peninsula are projected to increase up to 6 °C. Large increase in in the number of warm days (Tx90p) is found over sub equatorial Africa, with values up to more than 90 % in JAS, and more than 80 % in JFM over e.g., the gulf of Guinea, Central African Republic, South Sudan and Ethiopia. Changes in Tn90p (warm nights) are usually larger, with some models projecting Tn90p reaching 95 % starting from around 2060 even under RCP4.5 over the Gulf of Guinea and the Sahel. Results also show that the total length of heat spells projected to occur normally (i.e. once every 2 years) under RCP8.5 may be longer than those occurring once every 30 years under the lower emission scenario. By employing the recently developed HWMId index, it is possible to investigate the relationship between heat wave length ad intensity; in particular it is shown that very intense heat waves such as that occurring over the Horn of Africa may have values of HWMId larger than that of longer, but relatively weak, heat waves over West Africa.

  12. Developing High-resolution Soil Database for Regional Crop Modeling in East Africa

    NASA Astrophysics Data System (ADS)

    Han, E.; Ines, A. V. M.

    2014-12-01

    The most readily available soil data for regional crop modeling in Africa is the World Inventory of Soil Emission potentials (WISE) dataset, which has 1125 soil profiles for the world, but does not extensively cover countries Ethiopia, Kenya, Uganda and Tanzania in East Africa. Another dataset available is the HC27 (Harvest Choice by IFPRI) in a gridded format (10km) but composed of generic soil profiles based on only three criteria (texture, rooting depth, and organic carbon content). In this paper, we present a development and application of a high-resolution (1km), gridded soil database for regional crop modeling in East Africa. Basic soil information is extracted from Africa Soil Information Service (AfSIS), which provides essential soil properties (bulk density, soil organic carbon, soil PH and percentages of sand, silt and clay) for 6 different standardized soil layers (5, 15, 30, 60, 100 and 200 cm) in 1km resolution. Soil hydraulic properties (e.g., field capacity and wilting point) are derived from the AfSIS soil dataset using well-proven pedo-transfer functions and are customized for DSSAT-CSM soil data requirements. The crop model is used to evaluate crop yield forecasts using the new high resolution soil database and compared with WISE and HC27. In this paper we will present also the results of DSSAT loosely coupled with a hydrologic model (VIC) to assimilate root-zone soil moisture. Creating a grid-based soil database, which provides a consistent soil input for two different models (DSSAT and VIC) is a critical part of this work. The created soil database is expected to contribute to future applications of DSSAT crop simulation in East Africa where food security is highly vulnerable.

  13. In search of a viable IAU-OAD Regional Node: A case for Africa

    NASA Astrophysics Data System (ADS)

    Okere, B. I.; Okoh, D. C.; Obi, I. A.; Okeke, P. N.; Opara, F. E.

    2015-03-01

    The establishment of the IAU Office of Astronomy for Development (OAD) in Cape Town, South Africa, with the aim of using astronomy to stimulate development at all levels including primary, secondary and tertiary education, science research and the public understanding of science is a welcome development to consolidate the gains of IYA2009. To assist the IAU OAD office in achieving its goal of using astronomy as a tool for development, there is need to have OAD regional nodes. In this paper, we present the astronomy activities/programs required of such a Regional Node in Africa and how the Node can play a significant role to realise the vision of Astronomy for a better world!

  14. Tracking Enrolments and Graduations in Humanities Education in South Africa: Are We in Crisis?

    ERIC Educational Resources Information Center

    Yu, K.; Pillay, V.

    2011-01-01

    In this article we respond to the perceived crisis in humanities education in South Africa which posits firstly that large numbers of students are leaving this field and that secondly, the value of a humanities education has declined. To do this we track the enrolments and graduation rates in humanities at both undergraduate and postgraduate…

  15. The State of Humanities in Post-Apartheid South Africa--A Quantitative Story

    ERIC Educational Resources Information Center

    Pillay, V.; Yu, K.

    2010-01-01

    This article depicts the state of Humanities in post-apartheid South Africa by examining HEMIS enrolment and graduation data from 1999 to 2007. It demonstrates that although the decline in student enrolment and graduation in Humanities has not been severe; read in the context of substantial growth of all other disciplines, Humanities is in a…

  16. Improving regional health care in West Africa using current space systems and technology

    NASA Technical Reports Server (NTRS)

    Jemison, Mae C.; Thomas, J. Segun

    1992-01-01

    This paper discusses the issues involved with establishing an integrated satellite health network in West Africa based on currently available technology. The system proposed makes use of a central national facility capable of transmitting and receiving voice/data and video signals from the entire country. Regional, field and local facilities provide timely epidemiologic information, sharing of medical expertise through telemedical consultations, enhance optimized resource distribution and build a framework for telecommunications for the entire country.

  17. Improving regional health care in West Africa using current space systems and technology

    NASA Technical Reports Server (NTRS)

    Jemison, Mae C.; Thomas, J. S.

    1992-01-01

    This paper discusses the issues involved with establishing an integrated satellite health network in West Africa based on currently available technology. The system proposed makes use of a central national facility capable of transmitting and receiving voice/data and video signals from the entire country. Regional, field and local facilities provides timely epidemiologic information, sharing of medical expertise through telemedical consultations, enhances optimized resource distribution and builds a framework for telecommunications for the entire country.

  18. Attributing Climate Conditions for Stable Malaria Transmission to Human Activity in sub-Saharan Africa

    NASA Astrophysics Data System (ADS)

    Sheldrake, L.; Mitchell, D.; Allen, M. R.

    2015-12-01

    Temperature and precipitation limit areas of stable malaria transmission, but the effects of climate change on the disease remain controversial. Previously, studies have not separated the influence of anthropogenic climate change and natural variability, despite being an essential step in the attribution of climate change impacts. Ensembles of 2900 simulations of regional climate in sub-Saharan Africa for the year 2013, one representing realistic conditions and the other how climate might have been in the absence of human influence, were used to force a P.falciparium climate suitability model developed by the Mapping Malaria Risk in Africa project. Strongest signals were detected in areas of unstable transmission, indicating their heightened sensitivity to climatic factors. Evidently, impacts of human-induced climate change were unevenly distributed: the probability of conditions being suitable for stable malaria transmission were substantially reduced (increased) in the Sahel (Greater Horn of Africa (GHOA), particularly in the Ethiopian and Kenyan highlands). The length of the transmission season was correspondingly shortened in the Sahel and extended in the GHOA, by 1 to 2 months, including in Kericho (Kenya), where the role of climate change in driving recent malaria occurrence is hotly contested. Human-induced warming was primarily responsible for positive anomalies in the GHOA, while reduced rainfall caused negative anomalies in the Sahel. The latter was associated with anthropogenic impacts on the West African Monsoon, but uncertainty in the RCM's ability to reproduce precipitation trends in the region weakens confidence in the result. That said, outputs correspond well with broad-scale changes in observed endemicity, implying a potentially important contribution of anthropogenic climate change to the malaria burden during the past century. Results support the health-framing of climate risk and help indicate hotspots of climate vulnerability, providing

  19. Genetic and linguistic affinities between human populations in Eurasia and West Africa.

    PubMed

    Nettle, Daniel; Harriss, Louise

    2003-06-01

    This study examines the relationship between genetic distance and linguistic affiliation for five regional sets of populations from Eurasia and West Africa. Human genetic and linguistic diversity have been proposed to be generally correlated, either through a direct link, whereby linguistic and genetic affiliations reflect the same past population processes, or an indirect one, where the evolution of the two types of diversity is independent but conditioned by the same geographical factors. By controlling for proximity, indirect correlations due to common geography are eliminated, and any residual relationships found are likely to reflect common linguistic-genetic processes. Clear relationships between genetic distances and linguistic relatedness are detectable in Europe and East and Central Asia, but not in the Middle East, Southeast Asia, or West Africa. We suggest that linguistic and genetic affiliations will only be correlated under specific conditions, such as where there have been large-scale demic diffusions in the last few thousand years, and relative sedentism in the subsequent period.

  20. Tectonics, orbital forcing, global climate change, and human evolution in Africa: introduction to the African paleoclimate special volume.

    PubMed

    Maslin, Mark A; Christensen, Beth

    2007-11-01

    The late Cenozoic climate of Africa is a critical component for understanding human evolution. African climate is controlled by major tectonic changes, global climate transitions, and local variations in orbital forcing. We introduce the special African Paleoclimate Issue of the Journal of Human Evolution by providing a background for and synthesis of the latest work relating to the environmental context for human evolution. Records presented in this special issue suggest that the regional tectonics, appearance of C(4) plants in East Africa, and late Cenozoic global cooling combined to produce a long-term drying trend in East Africa. Of particular importance is the uplift associated with the East African Rift Valley formation, which altered wind flow patterns from a more zonal to more meridinal direction. Results in this volume suggest a marked difference in the climate history of southern and eastern Africa, though both are clearly influenced by the major global climate thresholds crossed in the last 3 million years. Papers in this volume present lake, speleothem, and marine paleoclimate records showing that the East African long-term drying trend is punctuated by episodes of short, alternating periods of extreme wetness and aridity. These periods of extreme climate variability are characterized by the precession-forced appearance and disappearance of large, deep lakes in the East African Rift Valley and paralleled by low and high wind-driven dust loads reaching the adjacent ocean basins. Dating of these records show that over the last 3 million years such periods only occur at the times of major global climatic transitions, such as the intensification of Northern Hemisphere Glaciation (2.7-2.5 Ma), intensification of the Walker Circulation (1.9-1.7 Ma), and the Mid-Pleistocene Revolution (1-0.7 Ma). Authors in this volume suggest this onset occurs as high latitude forcing in both Hemispheres compresses the Intertropical Convergence Zone so that East Africa

  1. Mechanisms Linking Land Use and Regional Climate Changes in West Africa

    NASA Astrophysics Data System (ADS)

    Wang, G.; Ahmed, K. F.; Yu, M.; JI, Z.; Pal, J. S.

    2014-12-01

    Land use land cover change is an important driver for regional climate changes in West Africa due to the strong land-atmosphere coupling. On the other hand, land use is also strongly influenced by climate changes due to the primarily rain-fed agriculture in this region and the relatively low capacity to adapt. It is therefore important that projections for future climate changes or land use changes account for the impact of the feedback between land use and climate. Land use influences regional climate through several different pathways, including changes in surface biogeophysical properties (e.g., surface albedo, Bowen ratio, surface roughness) that have been widely studied, and changes in the dynamic properties of the land surface influencing dust emission. The relative importance of these two pathways is likely to be model dependent and region dependent. In this study the effects of these two pathways will be evaluated and compared, based on results from a modeling framework that includes a regional climate-vegetation model, a crop growth model, an agricultural economics model, and a land use allocation model. This will be conducted in the context of future land use and climate change projections, with the ultimate objective to assess how agricultural land use in West Africa may change driven by climate and socioeconomic changes, and how the resulting land use change may further modify regional climate in the future.

  2. Coal and peat in the sub-Saharan region of Africa: alternative energy options?

    USGS Publications Warehouse

    Weaver, J.N.; Landis, E.R.

    1990-01-01

    Coal and peat are essentially unused and in some cases unknown in sub-Saharan Africa. However, they might comprise valuable alternative energy sources in some or all of the developing nations of the region. The 11 countries considered in this appraisal reportedly contain coal and peat. On the basis of regional geology, another five countries might also contain coal-bearing rocks. If the resource potential is adequate, coal and peat might be utilized in a variety of ways including substituting for fuelwood, generating electricity, supplying process heat for local industry and increasing agricultural productivity. -from Author

  3. AgMIP: New Results from Sub-Saharan Africa and South Asia Regional Integrated Assessments

    NASA Astrophysics Data System (ADS)

    Rosenzweig, C.

    2014-12-01

    AgMIP conducted the first set of comprehensive regional integrated assessments of climate change impacts on smallholder farmers in Sub-Saharan Africa and South Asia led by researchers from the regions themselves. The project developed new methods integrating climate, crop, livestock and economic models to conduct climate change impact assessments that characterize impacts on smallholder groups. AgMIP projections of climate change impacts on agriculture are more realistic than previous assessments because they take agricultural development into account. Using the best available data and models, the assessments directly evaluated yield, income, and poverty outcomes including the effects of adaptation packages and development pathways. Results show that even with agricultural development, climate change generally will exert negative pressure on yields of smallholder farmers in Sub-Saharan Africa and South Asia. Without adaptation, climate change leads to increased poverty in some locations in Sub-Saharan Africa and South Asia compared to a future in which climate change does not occur. Adaptation can significantly improve smallholder farmer responses to climate change. AgMIP expert teams identified improved varieties, sowing practices, fertilizer application, and irrigation applications as prioritized adaptation strategies. These targeted adaptation packages were able to overcome a portion of detrimental impacts but could not compensate completely in many locations. Even in cases where average impact is near zero, vulnerability (i.e., those at risk of loss) can be substantial even when mean impacts are positive.

  4. Choir singing in Subsaharan Africa: Acoustic factors of a regional style in southern Mozambique

    NASA Astrophysics Data System (ADS)

    Soeiro de Carvalho, Joao

    2005-09-01

    Choir singing is a most prominent form of expressive behavior in Subsaharan Africa. A vast majority of expressive modes involves multipart singing, both within the framework of European tonal system as well as other structured ways of combining vocal sounds of different frequencies. Vocal improvisation stands as an important process for the course of performance; individual voice ranges, as well as issues of social status and musical competence, determine the ways musicians participate in performance. Aesthetic validation is often expressed by the use of a nonverbal expressive mode, ``kulungwani,'' a vocal technique involving the action of the lower maxillae and tongue in order to produce a low-frequency interruption of sound emission. Choral singing intonation processes seem to rely on harmonic results, rather than melodic. A regional choral style in southern Africa seems to have developed, where a particular distribution of formant frequencies and an emphasis on low-frequency energy play a significant role.

  5. Politics and Human Welfare: Retinitis Pigmentosa Patients in South Africa.

    ERIC Educational Resources Information Center

    McKendrick, B. W.; Leketi, M.

    1990-01-01

    The study found that apartheid impacted the sociopsychological and physical circumstances of 12 African and 11 White people with retinitis pigmentosa in South Africa. Findings are discussed in terms of onset of condition, effects on subjects' lives, knowledge of social services, and needs unmet by existing services. (JDD)

  6. Regional assessment of atmospheric organic and black carbon in South Africa

    NASA Astrophysics Data System (ADS)

    Gideon van Zyl, Pieter; Maritz, Petra; Beukes, Johan Paul; Liousse, Cathy; Galy-Lacaux, Corinne; Castéra, Pierre; Venter, Andrew; Pienaar, Kobus

    2014-05-01

    At present limited data exists for atmospheric black carbon (BC) and organic carbon (OC) in South Africa. In this paper BC and OC concentrations were explored in terms of spatial and temporal patterns, mass fractions of BC and OC of the overall aerosol mass, as well as linked to possible sources. PM10 and PM2.5 samples were collected at five sampling sites in South Africa operated within the DEBITS IDAF network, i.e. Louis Trichardt, Skukuza, Vaal Triangle, Amersfoort and Botsalano, with MiniVol samplers. Samples were analysed with a Thermal/Optical Carbon analyser. OC were higher than BC concentrations at all sites in both size fractions. Most OC and BC were present in the PM2.5 fraction. OC/BC ratios reflected the location of the different DEBITS sites, with sites in or close to anthropogenic source regions having the lowest OC/BC ratios, while background sites had the highest OC/BC ratios. The OC mass fraction percentage varied between 1% and 24%, while the BC mass fraction ranged between 1 and 12 %. The highest OC mass fraction was found at Skukuza in the Kruger National Park, which was attributed to both natural sources and anthropogenic impacts from a dominant path of air mass movement from the anthropogenic industrial hub of South Africa. The highest mass fraction of BC was found at the Vaal Triangle situated within an region highly impacted by industry and household combustion for space heating and cooking. A relatively distinct seasonal pattern was observed, with higher OC and BC concentrations determined between May and October, which coincide with the dry season in the interior of South Africa. Positive correlations between OC and BC concentrations with the distance from back trajectories passing over veld fires were observed, indicating that veld fires contribute significantly to atmospheric OC and BC during the burning months.

  7. Review of Early Childhood Policy and Programs in Sub-Saharan Africa. World Bank Technical Paper No. 367, Africa Region Series.

    ERIC Educational Resources Information Center

    Colletta, Nat J.; Reinhold, Amy Jo

    Children in Sub-Saharan Africa face the greatest challenges to healthy development of any region in the world. This report presents reviews of 11 Early Childhood Development programs, studied to define financial and institutional conditions necessary to sustain early intervention efforts. Interviews and existing documentation from governmental and…

  8. Out of Africa: the importance of rivers as human migration corridors

    NASA Astrophysics Data System (ADS)

    Ramirez, J. A.; Coulthard, T. J.; Rogerson, M.; Barton, N.; Bruecher, T.

    2013-12-01

    The route and timing of Homo sapiens exiting Africa remains uncertain. Corridors leading out of Africa through the Sahara, the Nile Valley, and the Red Sea coast have been proposed as migration routes for anatomically modern humans 80,000-130,000 years ago. During this time climate conditions in the Sahara were wetter than present day, and monsoon rainfall fed rivers that flowed across the desert landscape. The location and timing of these rivers may have supported human migration northward from central Africa to the Mediterranean coast, and onwards to Europe or Asia. Here, we use palaeoclimate rainfall and a hydrological model to spatially simulate and quantitatively test the existence of three major rivers crossing the Sahara from south to north during the time of human migration. We provide evidence that, given realistic underlying climatology, the well-known Sahabi and Kufrah rivers very likely flowed across modern day Libya and reached the coast. More unexpectedly an additional river crossed the core of the Sahara through Algeria (Irharhar river) and flowed into the Chotts basin. The Irharhar river is unique, because it links locations in central Africa experiencing monsoon climates with temperate coastal Mediterranean environments where food and resources were likely abundant. From an ecological perspective, this little-known corridor may prove to be the most parsimonious migration route. Support for the Irharar as a viable migration corridor is provided by its geographic proximity to middle Stone Age archaeological artefacts found in North Africa. Our new, highly novel approach provides the first quantitative analysis of the likelihood that rivers occurred during the critical period of human migration out of Africa. Simulated probability of surface water in North Africa during the last interglacial and the location of tools and ornaments from the Middle Stone Age.

  9. Periodic isolation of the southern coastal plain of South Africa and the evolution of modern humans over late Quaternary glacial to interglacial cycles

    NASA Astrophysics Data System (ADS)

    Compton, J. S.

    2012-04-01

    Humans evolved in Africa, but where in Africa and by what mechanisms remain unclear. The evolution of modern humans over the last million years is associated with the onset of major global climate fluctuations, glacial to interglacial cycles, related to the build up and melting of large ice sheets in the Northern Hemisphere. During interglacial periods, such as today, warm and wet climates favored human expansion but during cold and dry glacial periods conditions were harsh and habitats fragmented. These large climate fluctuations periodically expanded and contracted African ecosystems and led to human migrations to more hospitable glacial refugia. Periodic isolation of relatively small numbers of humans may have allowed for their rapid evolutionary divergence from the rest of Africa. During climate transitions these divergent groups may have then dispersed and interbred with other groups (hybridization). Two areas at the opposite ends of Africa stand out as regions that were periodically isolated from the rest of Africa: North Africa (the Maghreb) and the southern coastal plain (SCP) of South Africa. The Maghreb is isolated by the Sahara Desert which periodically greens and is reconnected to the rest of Africa during the transition from glacial to interglacial periods. The SCP of South Africa is isolated from the rest of Africa by the rugged mountains of the Cape Fold Belt associated with inedible vegetation and dry climates to the north. The SCP is periodically opened when sea level falls by up to 130 m during glacial maxima to expose the present day submerged inner continental shelf. A five-fold expansion of the SCP receiving more rainfall in glacial periods may have served as a refuge to humans and large migratory herds. The expansive glacial SCP habitat abruptly contracts, by as much as one-third in 300 yr, during the rapid rise in sea level associated with glacial terminations. Rapid flooding may have increased population density and competition on the SCP to

  10. The monetary value of human milk in Francophone west Africa: a PROFILES analysis for nutrition policy communication.

    PubMed

    Aguayo, Víctor M; Ross, Jay

    2002-06-01

    Using a simple and conservative methodology, we estimated the volume and monetary value of the human milk produced by lactating women in Francophone West Africa. In that region, children zero to 35.9 months old consume over 1.1 billion liters of human milk per year. However, suboptimal breastfeeding practices account for the loss of 175 million liters of human milk annually. If the human milk consumed by children zero to 35.9 months old were to be adequately replaced using commercial breastmilk substitutes, an annual expenditure of about 2 billion US dollars would be needed. At the household level, the annual replacement cost of human milk would amount to US$412 per infant. This is beyond the reach of most families in West Africa, where as many as 61% of families in some countries live on less than one US dollar per day. Appropriate policies to foster breastfeeding need to be developed and adequately implemented. Such policy action is more likely to occur if decision makers fully appreciate the monetary value of human milk.

  11. Potential Risk of Regional Disease Spread in West Africa through Cross-Border Cattle Trade

    PubMed Central

    Dean, Anna S.; Fournié, Guillaume; Kulo, Abalo E.; Boukaya, G. Aboudou; Schelling, Esther; Bonfoh, Bassirou

    2013-01-01

    Background Transboundary animal movements facilitate the spread of pathogens across large distances. Cross-border cattle trade is of economic and cultural importance in West Africa. This study explores the potential disease risk resulting from large-scale, cross-border cattle trade between Togo, Burkina Faso, Ghana, Benin, and Nigeria for the first time. Methods and Principal Findings A questionnaire-based survey of livestock movements of 226 cattle traders was conducted in the 9 biggest cattle markets of northern Togo in February-March 2012. More than half of the traders (53.5%) operated in at least one other country. Animal flows were stochastically simulated based on reported movements and the risk of regional disease spread assessed. More than three quarters (79.2%, range: 78.1–80.0%) of cattle flowing into the market system originated from other countries. Through the cattle market system of northern Togo, non-neighbouring countries were connected via potential routes for disease spread. Even for diseases with low transmissibility and low prevalence in a given country, there was a high risk of disease introduction into other countries. Conclusions By stochastically simulating data collected by interviewing cattle traders in northern Togo, this study identifies potential risks for regional disease spread in West Africa through cross-border cattle trade. The findings highlight that surveillance for emerging infectious diseases as well as control activities targeting endemic diseases in West Africa are likely to be ineffective if only conducted at a national level. A regional approach to disease surveillance, prevention and control is essential. PMID:24130721

  12. 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.

  13. Taking forward the World TB Day 2016 theme 'Unite to End Tuberculosis' for the WHO Africa Region.

    PubMed

    Ntoumi, Francine; Kaleebu, Pontiano; Macete, Eusebio; Mfinanga, Sayoki; Chakaya, Jeremiah; Yeboah-Manu, Dorothy; Bates, Matthew; Mwaba, Peter; Maeurer, Markus; Petersen, Eskild; Zumla, Alimuddin

    2016-05-01

    Tuberculosis (TB) remains a global emergency, with an estimated 9.6 million new TB cases worldwide reported in 2014. Twenty-eight percent of these cases were in the World Health Organization (WHO) Africa Region, where the annual case detection rate was 281 per 100000 population-more than double the global average of 133 per 100000. Of the 9.6 million people who developed TB, an estimated 1.2 million (12%) were HIV-positive, and the Africa Region accounted for 74% of these cases. Three million people with TB remain undiagnosed and untreated. Globally, an estimated 480000 had multidrug-resistant TB (MDR-TB). Whilst of the African countries, only South Africa has reported a high prevalence of MDR-TB, it is likely that all of Sub-Saharan Africa has an unreported high load of drug-resistant TB. Tragically, in 2014, only 48% of individuals diagnosed with MDR-TB had successful treatment and an estimated 190000 people died of MDR-TB. Of the global TB funding gap of US$ 0.8 billion, the largest funding gap was in the Africa Region, amounting to US$ 0.4 billion in 2015. The MDR-TB pandemic in particular now threatens to devastate entire regions and may fundamentally alter the life-expectancy and demographic profile of many countries in Sub-Saharan Africa. The theme designated for this year's World TB Day, March 24, 2016, is 'Unite to End TB'. From the Africa Region, there is an urgent need to seriously address the political, economic, and social factors that influence host-Mycobacterium tuberculosis interactions and result in disease. Recent political and funder initiatives that provide renewed hope for the alleviation of Africa's TB and TB/HIV problems are discussed.

  14. WHO’s supported interventions on salt intake reduction in the sub-Saharan Africa region

    PubMed Central

    Munodawafa, Davison; Phori, Peter Malekele; Varenne, Benoit; Alisalad, Abdikamal

    2015-01-01

    Reduction of salt intake is an important and cost-effective way for reducing hypertension and the risk of cardiovascular diseases (CVDs). Current global salt intakes are estimated at around 10 g/day, well above the World Health Organization (WHO) recommended level of <5 g/day. The sub-Saharan Africa (SSA) region has a prevalence of hypertension of 46% among adults aged 25 and over and therefore strategies to reduce salt intake are necessary. This requires an understanding of salt intake behaviors in the population along with government commitment to increase awareness and take actions that would create an enabling environment. It is also important to have the food industry and other key stakeholders on board. A review of the developed WHO’s norms and guidelines, technical support provided to countries by WHO as well as country initiatives shows that countries in the African region are at different stages in the implementation of salt reduction interventions. For example, South Africa has enacted legislation to make the food industry reduce the salt content of a number of its products while Mauritius is requesting bakery owners to reduce salt in bread. A number of countries are currently undertaking studies to measure salt intake in the populations. Overall progress is slow as the region experiences a double burden of communicable and noncommunicable diseases, competing health priorities and limited resources for health. PMID:26090329

  15. Lower Silurian `hot shales' in North Africa and Arabia: regional distribution and depositional model

    NASA Astrophysics Data System (ADS)

    Lüning, S.; Craig, J.; Loydell, D. K.; Štorch, P.; Fitches, B.

    2000-03-01

    Lowermost Silurian organic-rich (`hot') shales are the origin of 80-90% of Palaeozoic sourced hydrocarbons in North Africa and also played a major role in petroleum generation on the Arabian Peninsula. In most cases, the shales were deposited directly above upper Ordovician (peri-) glacial sandstones during the initial early Silurian transgression that was a result of the melting of the late Ordovician icecap. Deposition of the main organic-rich shale unit in the North African/Arabian region was restricted to the earliest Silurian Rhuddanian stage ( acuminatus, atavus and probably early cyphus graptolite biozones). During this short period (1-2 m.y.), a favourable combination of factors existed which led to the development of exceptionally strong oxygen-deficiency in the area. In most countries of the study area, the post-Rhuddanian Silurian shales are organically lean and have not contributed to petroleum generation. The distribution and thickness of the basal Silurian `hot' shales have been mapped in detail for the whole North African region, using logs from some 300 exploration wells in Libya, Tunisia, Algeria and Morocco. In addition, all relevant, accessible published and unpublished surface and subsurface data of the lower Silurian shales in North Africa and Arabia have been reviewed, including sedimentological, biostratigraphic and organic geochemical data. The lowermost Silurian hot shales of northern Gondwana are laterally discontinuous and their distribution and thickness were controlled by the early Silurian palaeorelief which was shaped mainly by glacial processes of the late Ordovician ice age and by Pan-African and Infracambrian compressional and extensional tectonism. The thickest and areally most extensive basal Silurian organic-rich shales in North Africa occur in Algeria, Tunisia and western Libya, while on the Arabian Peninsula they are most prolific in Saudi Arabia, Oman, Jordan and Iraq. The hot shales were not deposited in Egypt, which was a

  16. Downscaling Reanalysis over Continental Africa with a Regional Model: NCEP Versus ERA Interim Forcing

    NASA Technical Reports Server (NTRS)

    Druyan, Leonard M.; Fulakeza, Matthew B.

    2013-01-01

    Five annual climate cycles (1998-2002) are simulated for continental Africa and adjacent oceans by a regional atmospheric model (RM3). RM3 horizontal grid spacing is 0.44deg at 28 vertical levels. Each of 2 simulation ensembles is driven by lateral boundary conditions from each of 2 alternative reanalysis data sets. One simulation downs cales National Center for Environmental Prediction reanalysis 2 (NCPR2) and the other the European Centre for Medium Range Weather Forecasts Interim reanalysis (ERA-I). NCPR2 data are archived at 2.5deg grid spacing, while a recent version of ERA-I provides data at 0.75deg spacing. ERA-I-forced simulations are recomrp. ended by the Coordinated Regional Downscaling Experiment (CORDEX). Comparisons of the 2 sets of simulations with each other and with observational evidence assess the relative performance of each downscaling system. A third simulation also uses ERA-I forcing, but degraded to the same horizontal resolution as NCPR2. RM3-simulated pentad and monthly mean precipitation data are compared to Tropical Rainfall Measuring Mission (TRMM) data, gridded at 0.5deg, and RM3-simulated circulation is compared to both reanalyses. Results suggest that each downscaling system provides advantages and disadvantages relative to the other. The RM3/NCPR2 achieves a more realistic northward advance of summer monsoon rains over West Africa, but RM3/ERA-I creates the more realistic monsoon circulation. Both systems recreate some features of JulySeptember 1999 minus 2002 precipitation differences. Degrading the resolution of ERA-I driving data unrealistically slows the monsoon circulation and considerably diminishes summer rainfall rates over West Africa. The high resolution of ERA-I data, therefore, contributes to the quality of the downscaling, but NCPR2laterai boundary conditions nevertheless produce better simulations of some features.

  17. Upper Pleistocene Human Dispersals out of Africa: A Review of the Current State of the Debate

    PubMed Central

    Beyin, Amanuel

    2011-01-01

    Although there is a general consensus on African origin of early modern humans, there is disagreement about how and when they dispersed to Eurasia. This paper reviews genetic and Middle Stone Age/Middle Paleolithic archaeological literature from northeast Africa, Arabia, and the Levant to assess the timing and geographic backgrounds of Upper Pleistocene human colonization of Eurasia. At the center of the discussion lies the question of whether eastern Africa alone was the source of Upper Pleistocene human dispersals into Eurasia or were there other loci of human expansions outside of Africa? The reviewed literature hints at two modes of early modern human colonization of Eurasia in the Upper Pleistocene: (i) from multiple Homo sapiens source populations that had entered Arabia, South Asia, and the Levant prior to and soon after the onset of the Last Interglacial (MIS-5), (ii) from a rapid dispersal out of East Africa via the Southern Route (across the Red Sea basin), dating to ~74–60 kya. PMID:21716744

  18. Upper Pleistocene Human Dispersals out of Africa: A Review of the Current State of the Debate.

    PubMed

    Beyin, Amanuel

    2011-01-01

    Although there is a general consensus on African origin of early modern humans, there is disagreement about how and when they dispersed to Eurasia. This paper reviews genetic and Middle Stone Age/Middle Paleolithic archaeological literature from northeast Africa, Arabia, and the Levant to assess the timing and geographic backgrounds of Upper Pleistocene human colonization of Eurasia. At the center of the discussion lies the question of whether eastern Africa alone was the source of Upper Pleistocene human dispersals into Eurasia or were there other loci of human expansions outside of Africa? The reviewed literature hints at two modes of early modern human colonization of Eurasia in the Upper Pleistocene: (i) from multiple Homo sapiens source populations that had entered Arabia, South Asia, and the Levant prior to and soon after the onset of the Last Interglacial (MIS-5), (ii) from a rapid dispersal out of East Africa via the Southern Route (across the Red Sea basin), dating to ~74-60 kya.

  19. Decline of birds in a human modified coastal dune forest landscape in South Africa.

    PubMed

    Trimble, Morgan J; van Aarde, Rudi J

    2011-01-13

    Previous studies demonstrate that old-growth forest remnants and vegetation regenerating after anthropogenic disturbance provide habitat for birds in a human modified coastal dune forest landscape in northern KwaZulu-Natal, South Africa. However, occurrence does not ensure persistence. Based on a 13-year monitoring database we calculated population trends for 37 bird species and general trends in overall bird density in different vegetation types. We evaluated species' characteristics as covariates of population trend and assessed changes in rainfall and proportional area and survey coverage per vegetation type. 76% of species assessed have declined, 57% significantly so at an average rate of 13.9% per year. Overall, bird density has fallen at 12.2% per year across old-growth forest and woody regenerating vegetation types. Changes in proportional area and coverage per vegetation type may partly explain trends for a few species but are unlikely to account for most. Below average rainfall may have contributed to bird declines. However, other possibilities warrant further investigation. Species with larger range extents tended to decline more sharply than did others, and these species may be responding to environmental changes on a broader geographical scale. Our results cast doubt on the future persistence of birds in this human modified landscape. More research is needed to elucidate the mechanisms driving population decline in the study area and to investigate whether the declines identified here are more widespread across the region and perhaps the continent.

  20. Human-caused fires limit convection in tropical Africa: First temporal observations and attribution

    NASA Astrophysics Data System (ADS)

    Tosca, M. G.; Diner, D. J.; Garay, M. J.; Kalashnikova, O. V.

    2015-08-01

    It is well established that smoke particles modify clouds, which in turn affects climate. However, no study has quantified the temporal dynamics of aerosol-cloud interactions with direct observations. Here for the first time, we use temporally offset satellite observations from northern Africa between 2006 and 2010 to quantitatively measure the effect of fire aerosols on convective cloud dynamics. We attribute a reduction in cloud fraction during periods of high aerosol optical depths to a smoke-driven inhibition of convection. We find that higher smoke burdens limit upward vertical motion, increase surface pressure, and increase low-level divergence—meteorological indicators of convective suppression. These results are corroborated by climate simulations that show a smoke-driven increase in regionally averaged shortwave tropospheric heating and decrease in convective precipitation during the fire season. Our results suggest that in tropical regions, anthropogenic fire initiates a positive feedback loop where increased aerosol emissions limit convection, dry the surface, and enable increased fire activity via human ignition.

  1. Were rivers flowing across the Sahara during the last interglacial? Implications for human migration through Africa.

    PubMed

    Coulthard, Tom J; Ramirez, Jorge A; Barton, Nick; Rogerson, Mike; Brücher, Tim

    2013-01-01

    Human migration north through Africa is contentious. This paper uses a novel palaeohydrological and hydraulic modelling approach to test the hypothesis that under wetter climates c.100,000 years ago major river systems ran north across the Sahara to the Mediterranean, creating viable migration routes. We confirm that three of these now buried palaeo river systems could have been active at the key time of human migration across the Sahara. Unexpectedly, it is the most western of these three rivers, the Irharhar river, that represents the most likely route for human migration. The Irharhar river flows directly south to north, uniquely linking the mountain areas experiencing monsoon climates at these times to temperate Mediterranean environments where food and resources would have been abundant. The findings have major implications for our understanding of how humans migrated north through Africa, for the first time providing a quantitative perspective on the probabilities that these routes were viable for human habitation at these times.

  2. Were Rivers Flowing across the Sahara During the Last Interglacial? Implications for Human Migration through Africa

    PubMed Central

    Coulthard, Tom J.; Ramirez, Jorge A.; Barton, Nick; Rogerson, Mike; Brücher, Tim

    2013-01-01

    Human migration north through Africa is contentious. This paper uses a novel palaeohydrological and hydraulic modelling approach to test the hypothesis that under wetter climates c.100,000 years ago major river systems ran north across the Sahara to the Mediterranean, creating viable migration routes. We confirm that three of these now buried palaeo river systems could have been active at the key time of human migration across the Sahara. Unexpectedly, it is the most western of these three rivers, the Irharhar river, that represents the most likely route for human migration. The Irharhar river flows directly south to north, uniquely linking the mountain areas experiencing monsoon climates at these times to temperate Mediterranean environments where food and resources would have been abundant. The findings have major implications for our understanding of how humans migrated north through Africa, for the first time providing a quantitative perspective on the probabilities that these routes were viable for human habitation at these times. PMID:24040347

  3. U.S. National Security Interests in Africa and the Future Global War on Terrorism (GWOT): A Proposal to Create an African Regional Combatant Command and a Regional African Special Operations Command

    DTIC Science & Technology

    2005-09-01

    Chad-Cameroon (Oil) and West Africa (Gas) pipeline projects leading to economic diversification in the agro- business, hydrological and manufacturing...77 ix LIST OF FIGURES Figure 1. Africa’s Multiple Regional Economic Groups. Africa Recovery: Volume 16, No. 2-3 September 2002...structures within Africa geo-politically continue to divide Africa by splitting economic and political regions, cultural zones, and economic trade

  4. The environmental context of human evolutionary history in Eurasia and Africa

    PubMed Central

    Elton, Sarah

    2008-01-01

    to negotiate, but their exploitation was accomplished by archaic and/or anatomically modern humans independently in Africa and south-east Asia. Complex social behaviour and material culture also allowed modern humans to reach some of the most hostile regions of the globe, above the Arctic Circle, by the late Pleistocene. This, with colonization of the Americas and Australasia, established Homo sapiens as a truly cosmopolitan species. PMID:18380862

  5. IFLA General Conference 1988. Division of Regional Activities. Sections on: Asia and Oceania; Africa; Latin America and the Caribbean; Australia.

    ERIC Educational Resources Information Center

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

    The eight papers in this collection focus on library activities in various geographical regions, e.g., Asia, Oceania, Africa, Latin America, the Caribbean, and Western Australia: (1) "Future Approaches and Prospects of Computerised Information Network among the Countries of South Asian Association for Regional Cooperation (SAARC)" (Abdullah…

  6. Infrastructure requirements for human papillomavirus vaccination and cervical cancer screening in sub-Saharan Africa.

    PubMed

    Sankaranarayanan, Rengaswamy; Anorlu, Rose; Sangwa-Lugoma, Ghislain; Denny, Lynette A

    2013-12-29

    The availability of both human papillomavirus (HPV) vaccination and alternative screening tests has greatly improved the prospects of cervical cancer prevention in sub-Saharan African (SSA) countries. The inclusion of HPV vaccine in the portfolio of new vaccines offered by the Gobal Alliance for Vaccines and Immunization (GAVI) to GAVI-eligible countries has vastly improved the chances of introducing HPV vaccination. Further investments to improve vaccine storage, distribution and delivery infrastructure and human resources of the Extended Programme of Immunization will substantially contribute to the faster introduction of HPV vaccination in SSA countries through both school- and campaign-based approaches. Alternative methods to cytology for the prevention of cervical cancer through the early detection and treatment of cervical cancer precursors have been extensively evaluated in the past 15 years, in Africa as well as in other low-resource settings. Visual inspection with 3-5% dilute acetic acid (VIA) and HPV testing are the two alternative screening methods that have been most studied, in both cross-sectional and randomised clinical trials. VIA is particularly suitable to low-resource settings; however, its efficacy in reducing cervical cancer is likely to be significantly lower than HPV testing. The introduction of VIA screening programmes will help develop the infrastructure that will, in turn, facilitate the introduction of affordable HPV testing in future. Links with the existing HIV/AIDS control programmes is another strategy to improve the infrastructure and screening services in SSA. Infrastructural requirements for an integrated approach aiming to vaccinate single-year cohorts of girls in the 9-13 years age-range and to screen women over 30 years of age using VIA or affordable rapid HPV tests are outlined in this manuscript. This article forms part of a regional report entitled "Comprehensive Control of HPV Infections and Related Diseases in the Sub

  7. Trials and projects on cervical cancer and human papillomavirus prevention in sub-Saharan Africa.

    PubMed

    Adefuye, Peter O; Broutet, Nathalie J; de Sanjosé, Silvia; Denny, Lynette A

    2013-12-29

    Cervical cancer is the leading cause of cancer morbidity and mortality in women in sub-Saharan Africa (SSA), accounting for about 50,000 deaths annually. Until recently, cytology was the gold standard for screening and prevention of cervical cancer. This method of screening has not been successful in SSA due to a lack of human, financial and material resources and poor health care infrastructure. It is estimated that less than 5% of at risk women have ever being screened. In the past two decades alternative approaches to cytology for cervical cancer screening have been evaluated in low- and medium-income countries. Visual inspection with acetic acid (VIA) and/or Lugol's iodine (VILI) have been shown to have adequate sensitivity, although low specificity, in a number of cross-sectional research and demonstration projects. Visual inspection methods require minimal resources, are technologically accessible, and are feasible for screening for precancerous lesions. Linking screening with VIA/VILI to treatment with cryotherapy may enable screening and treatment to take place in one visit, but this is likely to result in large numbers of women being subjected to unnecessary treatment. A number of studies have shown that cryotherapy is not associated with significant side effects or complications and is well tolerated. Creating the infrastructure for screening of older women is considered desirable, despite the limitations of visual inspection methods as screening tests. Understanding the role of human papillomavirus (HPV) infection in the etiology of cervical cancer and the discovery of HPV rapid test kits, as well as the development of vaccines against the HPV oncogenic types, have created new opportunities for prevention of cervical cancer. Trials and projects have established (and are still ongoing) the feasibility of using these molecular tests for screening. The ultimate in prevention method is primary prevention, offered by the advent of prophylactic vaccines

  8. MERS-CoV Antibodies in Humans, Africa, 2013–2014

    PubMed Central

    Liljander, Anne; Meyer, Benjamin; Jores, Joerg; Müller, Marcel A.; Lattwein, Erik; Njeru, Ian; Bett, Bernard; Corman, Victor Max

    2016-01-01

    Dromedaries in Africa and elsewhere carry the Middle East respiratory syndrome coronavirus (MERS-CoV). To search for evidence of autochthonous MERS-CoV infection in humans, we tested archived serum from livestock handlers in Kenya for MERS-CoV antibodies. Serologic evidence of infection was confirmed for 2 persons sampled in 2013 and 2014. PMID:27071076

  9. Language: The Gatekeeper of Humanity. Implications of South Africa's Language in Education Policies

    ERIC Educational Resources Information Center

    May, Judy J.

    2007-01-01

    English is perceived as the language of the powerful elite as well as a tool of oppression and dehumanization. English, as the medium of instruction in South Africa, functions as the barrier to full societal participation of native speakers (Webb, 2003, p.1) and the gatekeeper of humanity. This study combines historical and qualitative methods to…

  10. The Nairobi Report: Frameworks for Africa-UK Research Collaboration in the Social Sciences and Humanities

    ERIC Educational Resources Information Center

    Harle, Jonathan

    2009-01-01

    Across Sub-Saharan Africa it is evident that humanities and social sciences research is in urgent need of support. Universities and researchers face many challenges, the results of declining funding in the face of huge increases in enrollments. Infrastructure and facilities are insufficient and incomes have fallen. Many academics have been forced…

  11. 21st Century African Philosophy of Adult and Human Resource Education in Southern Africa

    ERIC Educational Resources Information Center

    Mutamba, Charlene

    2012-01-01

    This paper will attempt to define a philosophy of adult education for the purpose of workforce development in Southern Africa. The different influences such as Ubuntu and communalism, indigenous education, diversity western philosophy, globalization and technology are explored in the context of the Southern African region.

  12. Southern Africa Regional Office of Astronomy for Development: A New Hub for Astronomy for Development

    NASA Astrophysics Data System (ADS)

    Siseho Mutondo, Moola

    2015-08-01

    A new Astronomy for Development hub needs innovative tools and programs. SAROAD is developing exciting tools integrating Raspberry Pi® technology to bring cost-effective astronomy content to learning centres. SAROAD would also like to report achievements in realising the IAU's strategic plan. In order to manage, evaluate and coordinate regional IAU capacity building programmes, including the recruitment and mobilisation of volunteers, SAROAD has built an intranet that is accessible to regional members upon request. Using this resource, regional members can see and participate in regional activities. This resource also forms the foundation for closer collaboration between SAROAD member countries. SAROAD has commenced with projects in the three Task Force areas of Universities and Research, Children and Schools and Public Outreach. Under the three Task Force areas, a total of seven projects have commenced in Zambia. A further two projects involve the collaboration of Zambia and other regional member countries in order to foster engagement with important regional astronomy facilities (e.g. SKA). SAROAD has identified the IAU’s International Year of Light and a starting point for offering regional support for IAU-endorsed global activities. SAROAD has set up a hub dedicated to regional events and activities about the International Year of Light. SAROAD has a database of regional authorities to enable contact with the region's decision makers and experts. SAROAD will hold an annual event which brings forum for astronomy for development. The creation of the database and the SAROAD Road show is a first step towards this goal. The SAROAD website has helped to advertise upcoming events for astronomy development and education; it is used to provide advice, guidance and information for astronomers in all countries in the Southern Africa. Fundraising is the primary goal for SAROAD in 2015 towards financial self-sufficiency by 2020. We report on the methods that work best

  13. 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.

  14. Has Rift Valley fever virus evolved with increasing severity in human populations in East Africa?

    PubMed

    Baba, Marycelin; Masiga, Daniel K; Sang, Rosemary; Villinger, Jandouwe

    2016-06-22

    Rift Valley fever (RVF) outbreaks have occurred across eastern Africa from 1912 to 2010 approximately every 4-15 years, most of which have not been accompanied by significant epidemics in human populations. However, human epidemics during RVF outbreaks in eastern Africa have involved 478 deaths in 1998, 1107 reported cases with 350 deaths from 2006 to 2007 and 1174 cases with 241 deaths in 2008. We review the history of RVF outbreaks in eastern Africa to identify the epidemiological factors that could have influenced its increasing severity in humans. Diverse ecological factors influence outbreak frequency, whereas virus evolution has a greater impact on its virulence in hosts. Several factors could have influenced the lack of information on RVF in humans during earlier outbreaks, but the explosive nature of human RVF epidemics in recent years mirrors the evolutionary trend of the virus. Comparisons between isolates from different outbreaks have revealed an accumulation of genetic mutations and genomic reassortments that have diversified RVF virus genomes over several decades. The threat to humans posed by the diversified RVF virus strains increases the potential public health and socioeconomic impacts of future outbreaks. Understanding the shifting RVF epidemiology as determined by its evolution is key to developing new strategies for outbreak mitigation and prevention of future human RVF casualties.

  15. Has Rift Valley fever virus evolved with increasing severity in human populations in East Africa?

    PubMed Central

    Baba, Marycelin; Masiga, Daniel K; Sang, Rosemary; Villinger, Jandouwe

    2016-01-01

    Rift Valley fever (RVF) outbreaks have occurred across eastern Africa from 1912 to 2010 approximately every 4–15 years, most of which have not been accompanied by significant epidemics in human populations. However, human epidemics during RVF outbreaks in eastern Africa have involved 478 deaths in 1998, 1107 reported cases with 350 deaths from 2006 to 2007 and 1174 cases with 241 deaths in 2008. We review the history of RVF outbreaks in eastern Africa to identify the epidemiological factors that could have influenced its increasing severity in humans. Diverse ecological factors influence outbreak frequency, whereas virus evolution has a greater impact on its virulence in hosts. Several factors could have influenced the lack of information on RVF in humans during earlier outbreaks, but the explosive nature of human RVF epidemics in recent years mirrors the evolutionary trend of the virus. Comparisons between isolates from different outbreaks have revealed an accumulation of genetic mutations and genomic reassortments that have diversified RVF virus genomes over several decades. The threat to humans posed by the diversified RVF virus strains increases the potential public health and socioeconomic impacts of future outbreaks. Understanding the shifting RVF epidemiology as determined by its evolution is key to developing new strategies for outbreak mitigation and prevention of future human RVF casualties. PMID:27329846

  16. Sexual minorities, human rights and public health strategies in Africa.

    PubMed

    Epprecht, Marc

    2012-01-01

    Remarkable progress has been made towards the recognition of sexual minority rights in Africa. At the same time, a marked increase in attacks, rhetorical abuse, and restrictive legislation against sexual minorities or ‘homosexuality’ makes activism for sexual rights a risky endeavour in many African countries. Campaigns for sexual rights and ‘coming out’ are frequently perceived as a form of Western cultural imperialism, leading to an exportation of Western gay identities and provoking a patriotic defensiveness. Cultures of quiet acceptance of same-sex relationships or secretive bisexuality are meanwhile also problematic given the high rate of HIV prevalence on much of the continent. This article examines specific initiatives that are using subtle, somewhat covert means to negotiate a path between rights activism and secretive bisexuality. It argues that strategies primarily focused on health concerns that simultaneously yet discreetly promote sexual rights are having some success in challenging prevalent homophobic or ‘silencing’ cultures and discourses.

  17. Simulation of the annual and diurnal cycles of rainfall over South Africa by a regional climate model

    NASA Astrophysics Data System (ADS)

    Pohl, Benjamin; Rouault, Mathieu; Roy, Shouraseni Sen

    2014-10-01

    The capability of a current state-of-the-art regional climate model for simulating the diurnal and annual cycles of rainfall over a complex subtropical region is documented here. Hourly rainfall is simulated over Southern Africa for 1998-2006 by the non-hydrostatic model weather research and forecasting (WRF), and compared to a network of 103 stations covering South Africa. We used five simulations, four of which consist of different parameterizations for atmospheric convection at a 0.5 × 0.5° resolution, performed to test the physic-dependency of the results. The fifth experiment uses explicit convection over tropical South Africa at a 1/30° resolution. WRF simulates realistic mean rainfall fields, albeit wet biases over tropical Africa. The model mean biases are strongly modulated by the convective scheme used for the simulations. The annual cycle of rainfall is well simulated over South Africa, mostly influenced by tropical summer rainfall except in the Western Cape region experiencing winter rainfall. The diurnal cycle shows a timing bias, with atmospheric convection occurring too early in the afternoon, and causing too abundant rainfall. This result, particularly true in summer over the northeastern part of the country, is weakly physic-dependent. Cloud-resolving simulations do not clearly reduce the diurnal cycle biases. In the end, the rainfall overestimations appear to be mostly imputable to the afternoon hours of the austral summer rainy season, i.e., the periods during which convective activity is intense over the region.

  18. Human trafficking, labor brokering, and mining in southern Africa: responding to a decentralized and hidden public health disaster.

    PubMed

    Steele, Sarah

    2013-01-01

    Many southern African economies are dependent on the extractive industries. These industries rely on low-cost labor, often supplied by migrants, typically acquired through labor brokers. Very little attention has so far been paid to trafficking of men into extractive industries or its connection with trafficked women in the region's mining hubs. Recent reports suggest that labor-brokering practices foster human trafficking, both by exposing migrant men to lack of pay and exploitative conditions and by creating male migratory patterns that generate demand for sex workers and associated trafficking of women and girls. While trafficking in persons violates human rights, and thus remains a priority issue globally, there is little or no evidence of an effective political response to mine-related trafficking in southern Africa. This article concludes with recommendations for legal and policy interventions, as well as an enhanced public health response, which if implemented would help reduce human trafficking toward mining sites.

  19. Origin of clothing lice indicates early clothing use by anatomically modern humans in Africa.

    PubMed

    Toups, Melissa A; Kitchen, Andrew; Light, Jessica E; Reed, David L

    2011-01-01

    Clothing use is an important modern behavior that contributed to the successful expansion of humans into higher latitudes and cold climates. Previous research suggests that clothing use originated anywhere between 40,000 and 3 Ma, though there is little direct archaeological, fossil, or genetic evidence to support more specific estimates. Since clothing lice evolved from head louse ancestors once humans adopted clothing, dating the emergence of clothing lice may provide more specific estimates of the origin of clothing use. Here, we use a Bayesian coalescent modeling approach to estimate that clothing lice diverged from head louse ancestors at least by 83,000 and possibly as early as 170,000 years ago. Our analysis suggests that the use of clothing likely originated with anatomically modern humans in Africa and reinforces a broad trend of modern human developments in Africa during the Middle to Late Pleistocene.

  20. Origin of Clothing Lice Indicates Early Clothing Use by Anatomically Modern Humans in Africa

    PubMed Central

    Toups, Melissa A.; Kitchen, Andrew; Light, Jessica E.; Reed, David L.

    2011-01-01

    Clothing use is an important modern behavior that contributed to the successful expansion of humans into higher latitudes and cold climates. Previous research suggests that clothing use originated anywhere between 40,000 and 3 Ma, though there is little direct archaeological, fossil, or genetic evidence to support more specific estimates. Since clothing lice evolved from head louse ancestors once humans adopted clothing, dating the emergence of clothing lice may provide more specific estimates of the origin of clothing use. Here, we use a Bayesian coalescent modeling approach to estimate that clothing lice diverged from head louse ancestors at least by 83,000 and possibly as early as 170,000 years ago. Our analysis suggests that the use of clothing likely originated with anatomically modern humans in Africa and reinforces a broad trend of modern human developments in Africa during the Middle to Late Pleistocene. PMID:20823373

  1. Distal tephras of the eastern Lake Victoria basin, equatorial East Africa: correlations, chronology and a context for early modern humans

    NASA Astrophysics Data System (ADS)

    Blegen, Nick; Tryon, Christian A.; Faith, J. Tyler; Peppe, Daniel J.; Beverly, Emily J.; Li, Bo; Jacobs, Zenobia

    2015-08-01

    The tephrostratigraphic framework for Pliocene and Early Pleistocene paleoanthropological sites in East Africa has been well established through nearly 50 years of research, but a similarly comprehensive framework is lacking for the Middle and particularly the Late Pleistocene. We provide the first detailed regional record of Late Pleistocene tephra deposits associated with artifacts or fossils from the Lake Victoria basin of western Kenya. Correlations of Late Pleistocene distal tephra deposits from the Wasiriya beds on Rusinga Island, the Waware beds on Mfangano Island and deposits near Karungu, mainland Kenya, are based on field stratigraphy coupled with 916 electron microprobe analyses of eleven major and minor element oxides from 50 samples. At least eight distinct distal tephra deposits are distinguished, four of which are found at multiple localities spanning >60 km over an approximately north to south transect. New optically stimulated luminescence dates help to constrain the Late Pleistocene depositional ages of these deposits. Our correlation and characterization of volcaniclastic deposits expand and refine the current stratigraphy of the eastern Lake Victoria basin. This provides the basis for relating fossil- and artifact-bearing sediments and a framework for ongoing geological, archaeological and paleontological studies of Late Pleistocene East Africa, a crucial time period for human evolution and dispersal within and out of Africa.

  2. Africa-U.S. Higher Education Collaboration Initiative: Empowering African Higher Education for Africa's Transformation. A Discussion Paper for the Africa Region Post-Summit Workshop. Working Paper

    ERIC Educational Resources Information Center

    National Association of State Universities and Land-Grant Colleges, 2008

    2008-01-01

    This paper examines how higher education can contribute to Africa's transformation, reviews the challenges and priorities for higher education institution building, and introduces a proposed partnership program among African and U.S. higher education institutions to strengthen African higher education. In July of 2007 the National Association of…

  3. Aerosol Radiative Forcing and Regional Climate Impact over Middle East and North Africa

    NASA Astrophysics Data System (ADS)

    Bangalth, H. K.; Stenchikov, G.; Zampieri, M.; Bantges, R.; Brindley, H.

    2012-04-01

    Middle East and North Africa (MENA) is a unique region due in part to the abundance of atmospheric aerosols and their significant contribution to the energy balance of the region. Mineral dust plays a leading role in this process. In this study we evaluate the radiative forcing of dust aerosols in the MENA region and their impact on the regional circulation and temperature distribution using a global high-resolution atmospheric model HIRAM developed at the NOAA Geophysical Fluid Dynamics Laboratory. We found that dust aerosols reduce downward radiative fluxes at surface up to 30 W/m2 and warm by about this amount the lower five-km-deep atmospheric layer. To better quantify radiative impact of aerosols we have employed the available aerosol satellite observations that primarily provide column integral aerosol optical depth (AOD), as a measure of aerosol burden. Climatology of AOD from different satellites (MODIS, MISR, SEVIRI and CALIPSO) over MENA and their inter comparison is made to have a comprehension of the discrepancies and agreement between them. Though the observed AODs vary among the different instruments spatially and temporally, the difference falls within a factor of less than two. We implement these observed aerosols in HIRAM. The radiative forcing corresponding to the satellite aerosol observation and the sensitivity of regional climate to this forcing are analyzed. The analysis shows that the differential heating in the vertical and the corresponding response of the vertical temperature profile have a profound impact on the tropospheric dynamics and the structure of the boundary layer.

  4. Regional assessment of the hydropower potential of rivers in West Africa

    NASA Astrophysics Data System (ADS)

    Kling, Harald; Stanzel, Philipp; Fuchs, Martin

    2016-04-01

    The 15 countries of the Economic Community of West African States (ECOWAS) face a constant shortage of energy supply, which limits sustained economic growth. Currently there are about 50 operational hydropower plants and about 40 more are under construction or refurbishment. The potential for future hydropower development - especially for small-scale plants in rural areas - is assumed to be large, but exact data are missing. This study supports the energy initiatives of the "ECOWAS Centre for Renewable Energy and Energy Efficiency" (ECREEE) by assessing the hydropower potential of all rivers in West Africa. For more than 500,000 river reaches the hydropower potential was computed from channel slope and mean annual discharge. In large areas there is a lack of discharge observations. Therefore, an annual water balance model was used to simulate discharge. The model domain covers 5 Mio km², including e.g. the Niger, Volta, and Senegal River basins. The model was calibrated with observed data of 410 gauges, using precipitation and potential evapotranspiration data as inputs. Historic variations of observed annual discharge between 1950 and 2010 are simulated well by the model. As hydropower plants are investments with a lifetime of several decades we also assessed possible changes in future discharge due to climate change. To this end the water balance model was driven with bias-corrected climate projections of 15 Regional Climate Models for two emission scenarios of the CORDEX-Africa ensemble. The simulation results for the river network were up-scaled to sub-areas and national summaries. This information gives a regional quantification of the hydropower potential, expected climate change impacts, as well as a regional classification for general suitability (or non-suitability) of hydropower plant size - from small-scale to large projects.

  5. Neogene cratonic erosion fluxes and landform evolution processes from regional regolith mapping (Burkina Faso, West Africa)

    NASA Astrophysics Data System (ADS)

    Grimaud, Jean-Louis; Chardon, Dominique; Metelka, Václav; Beauvais, Anicet; Bamba, Ousmane

    2015-07-01

    The regionally correlated and dated regolith-paleolandform sequence of Sub-Saharan West Africa offers a unique opportunity to constrain continental-scale regolith dynamics as the key part of the sediment routing system. In this study, a regolith mapping protocol is developed and applied at the scale of Southwestern Burkina Faso. Mapping combines field survey and remote sensing data to reconstruct the topography of the last pediplain that formed over West Africa in the Early and Mid-Miocene (24-11 Ma). The nature and preservation pattern of the pediplain are controlled by the spatial variation of bedrock lithology and are partitioned among large drainage basins. Quantification of pediplain dissection and drainage growth allows definition of a cratonic background denudation rate of 2 m/My and a minimum characteristic timescale of 20 Ma for shield resurfacing. These results may be used to simulate minimum export fluxes of drainage basins of constrained size over geological timescales. Background cratonic denudation results in a clastic export flux of ~ 4 t/km2/year, which is limited by low denudation efficiency of slope processes and correlatively high regolith storage capacity of tropical shields. These salient characteristics of shields' surface dynamics would tend to smooth the riverine export fluxes of shields through geological time.

  6. A seasonal agricultural drought forecast system for food-insecure regions of East Africa

    USGS Publications Warehouse

    Shukla, Shraddhanand; McNally, Amy; Husak, Gregory; Funk, Christopher C.

    2014-01-01

     The increasing food and water demands of East Africa's growing population are stressing the region's inconsistent water resources and rain-fed agriculture. More accurate seasonal agricultural drought forecasts for this region can inform better water and agricultural management decisions, support optimal allocation of the region's water resources, and mitigate socio-economic losses incurred by droughts and floods. Here we describe the development and implementation of a seasonal agricultural drought forecast system for East Africa (EA) that provides decision support for the Famine Early Warning Systems Network's science team. We evaluate this forecast system for a region of equatorial EA (2° S to 8° N, and 36° to 46° E) for the March-April-May growing season. This domain encompasses one of the most food insecure, climatically variable and socio-economically vulnerable regions in EA, and potentially the world: this region has experienced famine as recently as 2011. To assess the agricultural outlook for the upcoming season our forecast system simulates soil moisture (SM) scenarios using the Variable Infiltration Capacity (VIC) hydrologic model forced with climate scenarios for the upcoming season. First, to show that the VIC model is appropriate for this application we forced the model with high quality atmospheric observations and found that the resulting SM values were consistent with the Food and Agriculture Organization's (FAO's) Water Requirement Satisfaction Index (WRSI), an index used by FEWS NET to estimate crop yields. Next we tested our forecasting system with hindcast runs (1993–2012). We found that initializing SM forecasts with start-of-season (5 March) SM conditions resulted in useful SM forecast skill (> 0.5 correlation) at 1-month, and in some cases at 3 month lead times. Similarly, when the forecast was initialized with mid-season (i.e. 5 April) SM conditions the skill until the end-of-season improved. This shows that early-season rainfall

  7. A seasonal agricultural drought forecast system for food-insecure regions of East Africa

    NASA Astrophysics Data System (ADS)

    Shukla, S.; McNally, A.; Husak, G.; Funk, C.

    2014-10-01

    The increasing food and water demands of East Africa's growing population are stressing the region's inconsistent water resources and rain-fed agriculture. More accurate seasonal agricultural drought forecasts for this region can inform better water and agropastoral management decisions, support optimal allocation of the region's water resources, and mitigate socioeconomic losses incurred by droughts and floods. Here we describe the development and implementation of a seasonal agricultural drought forecast system for East Africa (EA) that provides decision support for the Famine Early Warning Systems Network's (FEWS NET) science team. We evaluate this forecast system for a region of equatorial EA (2° S-8° N, 36-46° E) for the March-April-May (MAM) growing season. This domain encompasses one of the most food-insecure, climatically variable, and socioeconomically vulnerable regions in EA, and potentially the world; this region has experienced famine as recently as 2011. To produce an "agricultural outlook", our forecast system simulates soil moisture (SM) scenarios using the Variable Infiltration Capacity (VIC) hydrologic model forced with climate scenarios describing the upcoming season. First, we forced the VIC model with high-quality atmospheric observations to produce baseline soil moisture (SM) estimates (here after referred as SM a posteriori estimates). These compared favorably (correlation = 0.75) with the water requirement satisfaction index (WRSI), an index that the FEWS NET uses to estimate crop yields. Next, we evaluated the SM forecasts generated by this system on 5 March and 5 April of each year between 1993 and 2012 by comparing them with the corresponding SM a posteriori estimates. We found that initializing SM forecasts with start-of-season (SOS) (5 March) SM conditions resulted in useful SM forecast skill (> 0.5 correlation) at 1-month and, in some cases, 3-month lead times. Similarly, when the forecast was initialized with midseason (i.e., 5

  8. A seasonal agricultural drought forecast system for food-insecure regions of East Africa

    NASA Astrophysics Data System (ADS)

    Shukla, S.; McNally, A.; Husak, G.; Funk, C.

    2014-03-01

    The increasing food and water demands of East Africa's growing population are stressing the region's inconsistent water resources and rain-fed agriculture. More accurate seasonal agricultural drought forecasts for this region can inform better water and agricultural management decisions, support optimal allocation of the region's water resources, and mitigate socio-economic losses incurred by droughts and floods. Here we describe the development and implementation of a seasonal agricultural drought forecast system for East Africa (EA) that provides decision support for the Famine Early Warning Systems Network's science team. We evaluate this forecast system for a region of equatorial EA (2° S to 8° N, and 36° to 46° E) for the March-April-May growing season. This domain encompasses one of the most food insecure, climatically variable and socio-economically vulnerable regions in EA, and potentially the world: this region has experienced famine as recently as 2011. To assess the agricultural outlook for the upcoming season our forecast system simulates soil moisture (SM) scenarios using the Variable Infiltration Capacity (VIC) hydrologic model forced with climate scenarios for the upcoming season. First, to show that the VIC model is appropriate for this application we forced the model with high quality atmospheric observations and found that the resulting SM values were consistent with the Food and Agriculture Organization's (FAO's) Water Requirement Satisfaction Index (WRSI), an index used by FEWS NET to estimate crop yields. Next we tested our forecasting system with hindcast runs (1993-2012). We found that initializing SM forecasts with start-of-season (5 March) SM conditions resulted in useful SM forecast skill (> 0.5 correlation) at 1-month, and in some cases at 3 month lead times. Similarly, when the forecast was initialized with mid-season (i.e. 5 April) SM conditions the skill until the end-of-season improved. This shows that early-season rainfall is

  9. Chromosomal radiosensitivity of human immunodeficiency virus positive/negative cervical cancer patients in South Africa

    PubMed Central

    HERD, OLIVIA; FRANCIES, FLAVIA; KOTZEN, JEFFREY; SMITH, TRUDY; NXUMALO, ZWIDE; MULLER, XANTHENE; SLABBERT, JACOBUS; VRAL, ANNE; BAEYENS, ANS

    2016-01-01

    Cervical cancer is the second most common cancer amongst South African women and is the leading cause of cancer-associated mortality in this region. Several international studies on radiation-induced DNA damage in lymphocytes of cervical cancer patients have remained inconclusive. Despite the high incidence of cervical cancer in South Africa, and the extensive use of radiotherapy to treat it, the chromosomal radiosensitivity of South African cervical cancer patients has not been studied to date. Since a high number of these patients are human immunodeficiency virus (HIV)-positive, the effect of HIV infection on chromosomal radiosensitivity was also investigated. Blood samples from 35 cervical cancer patients (20 HIV-negative and 15 HIV-positive) and 20 healthy controls were exposed to X-rays at doses of 6 MV of 2 and 4 Gy in vitro. Chromosomal radiosensitivity was assessed using the micronucleus (MN) assay. MN scores were obtained using the Metafer 4 platform, an automated microscopic system. Three scoring methods of the MNScore module of Metafer were applied and compared. Cervical cancer patients had higher MN values than healthy controls, with HIV-positive patients having the highest MN values. Differences between groups were significant when using a scoring method that corrects for false positive and false negative MN. The present study suggested increased chromosomal radiosensitivity in HIV-positive South African cervical cancer patients. PMID:26549042

  10. The 'Out of Africa' Hypothesis, Human Genetic Diversity, and Comparative Economic Development

    PubMed Central

    Ashraf, Quamrul; Galor, Oded

    2013-01-01

    This research argues that deep-rooted factors, determined tens of thousands of years ago, had a significant effect on the course of economic development from the dawn of human civilization to the contemporary era. It advances and empirically establishes the hypothesis that, in the course of the exodus of Homo sapiens out of Africa, variation in migratory distance from the cradle of humankind to various settlements across the globe affected genetic diversity and has had a long-lasting effect on the pattern of comparative economic development that is not captured by geographical, institutional, and cultural factors. In particular, the level of genetic diversity within a society is found to have a hump-shaped effect on development outcomes in both the pre-colonial and the modern era, reflecting the trade-off between the beneficial and the detrimental effects of diversity on productivity. While the intermediate level of genetic diversity prevalent among Asian and European populations has been conducive for development, the high degree of diversity among African populations and the low degree of diversity among Native American populations have been a detrimental force in the development of these regions. PMID:25506083

  11. 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.

  12. A vectorial capacity product to monitor changing malaria transmission potential in epidemic regions of Africa

    USGS Publications Warehouse

    Ceccato, Pietro; Vancutsem, Christelle; Klaver, Robert; Rowland, James; Connor, Stephen J.

    2012-01-01

    Rainfall and temperature are two of the major factors triggering malaria epidemics in warm semi-arid (desert-fringe) and high altitude (highland-fringe) epidemic risk areas. The ability of the mosquitoes to transmit Plasmodium spp. is dependent upon a series of biological features generally referred to as vectorial capacity. In this study, the vectorial capacity model (VCAP) was expanded to include the influence of rainfall and temperature variables on malaria transmission potential. Data from two remote sensing products were used to monitor rainfall and temperature and were integrated into the VCAP model. The expanded model was tested in Eritrea and Madagascar to check the viability of the approach. The analysis of VCAP in relation to rainfall, temperature and malaria incidence data in these regions shows that the expanded VCAP correctly tracks the risk of malaria both in regions where rainfall is the limiting factor and in regions where temperature is the limiting factor. The VCAP maps are currently offered as an experimental resource for testing within Malaria Early Warning applications in epidemic prone regions of sub-Saharan Africa. User feedback is currently being collected in preparation for further evaluation and refinement of the VCAP model.

  13. Regional Climate Response to Volcanic Radiative Forcing in Middle East and North Africa

    NASA Astrophysics Data System (ADS)

    Stenchikov, G.; Dogar, M.

    2012-04-01

    We have tested the regional climate sensitivity in the Middle East and North Africa (MENA) to radiation perturbations caused by the large explosive equatorial volcanic eruptions of the second part of 20th century, El Chichon and Pinatubo occurred, respectively, in 1982 and 1991. The observations and reanalysis data show that the surface volcanic cooling in the MENA region is two-three times larger than the global mean response to volcanic forcing. The Red Sea surface temperature appears to be also very sensitive to the external radiative impact. E.g., the sea surface cooling, associated with the 1991 Pinatubo eruption, caused deep water mixing and coral bleaching for a few years. To better quantify these effects we use the Geophysical Fluid Dynamics Laboratory global High Resolution Atmospheric Model (HIRAM) to conduct simulations of both the El Chichon and Pinatubo impacts with the effectively 25-km grid spacing. We find that the circulation changes associated with the positive phase of the arctic oscillation amplified the winter temperature anomalies in 1982-1984 and 1991-1993. The dynamic response to volcanic cooling also is characterized by the southward shift of the inter-tropical convergence zone in summer and associated impact on the precipitation patterns. Thus, these results suggest that the climate regime in the MENA region is highly sensitive to external forcing. This is important for better understanding of the climate variability and change in this region.

  14. Human infections due to Salmonella Blockley, a rare serotype in South Africa: a case report

    PubMed Central

    2012-01-01

    Background Infections due to nontyphoidal Salmonella have increased worldwide over the last couple of decades. Salmonella enterica serotype Blockley (Salmonella Blockley) infections is associated with chickens and is a rarely isolated serotype in human infections in most countries. Case presentation We report a case of human infections due to Salmonella Blockley in KwaZulu-Natal, South Africa in 2011. Three African males (aged 4, 14 and 16) presented to a clinic with diarrhoea, stomach cramps and headache. They started experiencing signs of illness a day after they consumed a common meal, consisting of meat, rice and potatoes. Stool specimens from the patients cultured Salmonella Blockley. The strains showed an indistinguishable pulsed-field gel electrophoresis pattern. Conclusion This is the first recorded case of human infections due to Salmonella Blockley in South Africa. PMID:23050633

  15. [Population trends in the Mediterranean region: socioeconomic problems associated with the situation in the countries of North Africa].

    PubMed

    Baldi, S

    1990-01-01

    The impact of current rates of population growth on the economies of the countries of North Africa is assessed. The author notes that the countries of the region had agreed in January 1990 to implement as soon as possible a policy of free circulation of migrants among Algeria, Tunisia, Morocco, Mauritania, and Libya in order to reduce levels of emigration from the region and to help resolve labor-supply problems within the region.

  16. Diet, Genetics, and Disease: A Focus on the Middle East and North Africa Region

    PubMed Central

    Fahed, Akl C.; El-Hage-Sleiman, Abdul-Karim M.; Farhat, Theresa I.; Nemer, Georges M.

    2012-01-01

    The Middle East and North Africa (MENA) region suffers a drastic change from a traditional diet to an industrialized diet. This has led to an unparalleled increase in the prevalence of chronic diseases. This review discusses the role of nutritional genomics, or the dietary signature, in these dietary and disease changes in the MENA. The diet-genetics-disease relation is discussed in detail. Selected disease categories in the MENA are discussed starting with a review of their epidemiology in the different MENA countries, followed by an examination of the known genetic factors that have been reported in the disease discussed, whether inside or outside the MENA. Several diet-genetics-disease relationships in the MENA may be contributing to the increased prevalence of civilization disorders of metabolism and micronutrient deficiencies. Future research in the field of nutritional genomics in the MENA is needed to better define these relationships. PMID:22536488

  17. One of a kind--the Pan African Clinical Trials Registry, a regional registry for Africa.

    PubMed

    Abrams, Amber L

    2011-01-01

    The 2004 Ministerial Summit on Health Research called on the World Health Organization to to establish a registry network with the intention of providing a single access point to identify trials. In 2007 the International Committee of Medical Journal Editors amended their support of this initiative stating that only trials registered prospectively on a member registry of the WHO's Network of Primary Registers would be published. The Pan African Clinical Trials Registry (www.pactr.org), was established in early 2007 as the AIDS, TB and Malaria (ATM) Clinical Trials Registry with the aim of piloting the concept of a registry that would cater to the specific needs of African trialists. In 2009 the ATM Registry expanded its remit to include all diseases for all regions of Africa; The Pan African Clinical Trials Registry became the first and is presently the only African member of the World Health Organization's Network of Primary Registers.

  18. Role of dynamic vegetation in regional climate predictions over western Africa

    NASA Astrophysics Data System (ADS)

    Alo, Clement Aga; Wang, Guiling

    2010-10-01

    This study examines the role of vegetation dynamics in regional predictions of future climate change in western Africa using a dynamic vegetation model asynchronously coupled to a regional climate model. Two experiments, one for present day and one for future, are conducted with the linked regional climate-vegetation model, and the third with the regional climate model standing alone that predicts future climate based on present-day vegetation. These simulations are so designed in order to tease out the impact of structural vegetation feedback on simulated climate and hydrological processes. According to future predictions by the regional climate-vegetation model, increase in LAI is widespread, with significant shift in vegetation type. Over the Guinean Coast in 2084-2093, evergreen tree coverage decreases by 49% compared to 1984-1993, while drought deciduous tree coverage increases by 56%. Over the Sahel region in the same period, grass cover increases by 31%. Such vegetation changes are accompanied by a decrease of JJA rainfall by 2% over the Guinean Coast and an increase by 23% over the Sahel. This rather small decrease or large increase of precipitation is largely attributable to the role of vegetation feedback. Without the feedback effect from vegetation, the regional climate model would have predicted a 5% decrease of JJA rainfall in both the Guinean Coast and the Sahel as a result of the radiative and physiological effects of higher atmospheric CO2 concentration. These results demonstrate that climate- and CO2-induced changes in vegetation structure modify hydrological processes and climate at magnitudes comparable to or even higher than the radiative and physiological effects, thus evincing the importance of including vegetation feedback in future climate predictions.

  19. 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

  20. Reconciliation and Revenge in Post-Apartheid South Africa. Rethinking Legal Pluralism and Human Rights.

    PubMed

    Wilson

    2000-02-01

    Human rights are a central element in the new governmental project in the new South Africa, and this article traces some of the specific forms of connection and disconnection between notions of justice found in townships of the Vaal and rights discourses as articulated by the Truth and Reconciliation Commission. The introduction of human rights in post-apartheid South Africa has had varied social effects. Religious values and human rights discourse have converged on the notion of reconciliation on the basis of shared value orientations and institutional structures. There are clear divergences, however, between human rights ideas and the notions of justice expressed in local lekgotla, or township courts, which emphasize punishment and retribution. The article concludes that the plurality of legal orders in South Africa results not from systemic relations between law and society but from multiple forms of social action seeking to alter the direction of social change in the area of justice within the context of the nation-building project of the post-apartheid state.

  1. Earliest modern humans in southern Africa dated by isoleucine epimerization in ostrich eggshell

    NASA Astrophysics Data System (ADS)

    Miller, G. H.; Beaumont, P. B.; Deacon, H. J.; Brooks, A. S.; Hare, P. E.; Jull, A. J. T.

    1999-11-01

    The oldest anatomically modern human remains are beyond the range of radiocarbon dating, and associated deposits lack material suitable for most other dating methods. Consequently, age estimates for early human skeletal material and correlative stratigraphic horizons in southern Africa are frequently based on paleoclimatic correlations to the deep-sea record and extrapolated sedimentation rates, both of which incorporate a number of untested assumptions. Here we focus on one substage of the Middle Stone Age of southern Africa, the Howiesons Poort industry, a distinctive culture-stratigraphic marker in sequences south of the Zambezi. Anatomically modern human skeletal material has been found associated with, or even older than the Howiesons Poort layer in stratified deposits at Border Cave and Klasies River main site. We have dated or bracketed the Howiesons Poort horizon at Border Cave, Boomplaas Cave and Apollo 11 Cave, three stratified cave sites in southern Africa, based on the extent of isoleucine epimerization in associated ostrich eggshells. We conclude that the Howiesons Poort lithic industry is bracketed by limiting dates of 56 and 80 ka, and is most likely centered on 66±5 ka. Anatomically modern human remains in deeper levels are more than 100 ka old, lending support to the hypothesis of an African origin for Homo sapiens.

  2. The New Regionalism in Sub-Saharan Africa: More Than Meets the Eye? Policy Brief No. 20

    ERIC Educational Resources Information Center

    Goldstein, Andrea

    2002-01-01

    Following independence in sub-Saharan Africa in the 1960s, traditional integration strategies produced disappointing results in most instances, as they started with very modest levels of intra-regional trade, marked differences in income and industrialisation levels and diffuse fiscal weakness. They also had a strong protectionist bias, trying to…

  3. A coupled regional climate model for the Lake Victoria basin of East Africa

    NASA Astrophysics Data System (ADS)

    Song, Yi; Semazzi, Fredrick H. M.; Xie, Lian; Ogallo, Laban J.

    2004-01-01

    A nested coupled model has been developed to investigate the two-way interactions between the regional climate of eastern Africa and Lake Victoria. The atmospheric component of the model is the North Carolina State University (NCSU) version of the National Center for Atmospheric Research (NCAR) regional climate model (NCSU-RegCM2). The lake component of the model is based on the Princeton ocean model (POM).Three simulations, each 4 months long, have been performed for the short rains of eastern Africa of September through to December. The control experiment is based on the standard NCSU-RegCM2 model coupled to a one-dimensional model of Lake Victoria. The second experiment was based on the stand-alone three-dimensional primitive equation POM-Lake Victoria model forced by output from the atmospheric component of the control run. The third experiment is based on the integration of the coupled system of the NCSU-RegCM2 model where the one-dimensional lake model in the control run has been replaced by the three-dimensional POM hydrodynamical model for Lake Victoria.The results confirm that adopting the traditional modelling approach, in which the lake hydrodynamics are neglected and the formulation is based entirely on thermodynamics alone, is not entirely satisfactory for the Lake Victoria basin. Such a strategy precludes the transport of heat realistically within the lake, from the heat surplus regions to the cooler regions, and thereby results in a degraded simulation of the climate downstream over the rest of the lake and the surrounding land regions. The numerical simulations show that the southwestern region of the lake is an important source of warm water because it is relatively shallower and the water column is heated up much more quickly during the day than the rest of the lake. The result is that the surface temperature anomaly field from the all-lake area average consists of a gradient pattern with warmer water over the shallow region of the lake over the

  4. Ancient Human Migration after Out-of-Africa

    PubMed Central

    Shriner, Daniel; Tekola-Ayele, Fasil; Adeyemo, Adebowale; Rotimi, Charles N.

    2016-01-01

    The serial founder model of modern human origins predicts that the phylogeny of ancestries exhibits bifurcating, tree-like behavior. Here, we tested this prediction using three methods designed to investigate gene flow in autosome-wide genotype data from 3,528 unrelated individuals from 163 global samples. Specifically, we investigated whether Cushitic ancestry has an East African or Middle Eastern origin. We found evidence for non-tree-like behavior in the form of four migration events. First, we found that Cushitic ancestry is a mixture of ancestries closely related to Arabian ancestry and Nilo-Saharan or Omotic ancestry. We found evidence for additional migration events in the histories of: 1) Indian and Arabian ancestries, 2) Kalash ancestry, and 3) Native American and Northern European ancestries. These findings, based on analysis of ancestry of present-day humans, reveal migration in the distant past and provide new insights into human history. PMID:27212471

  5. Human rights advances in women's reproductive health in Africa.

    PubMed

    Ngwena, Charles G; Brookman-Amissah, Eunice; Skuster, Patty

    2015-05-01

    The African Commission on Human and Peoples' Rights recently adopted General Comment No 2 to interpret provisions of Article 14 of the Protocol to the African Charter on the Rights Women. The provisions relate to women's rights to fertility control, contraception, family planning, information and education, and abortion. The present article highlights the General Comment's potential to promote women's sexual and reproductive rights in multiple ways. The General Comment's human rights value goes beyond providing states with guidance for framing their domestic laws, practices, and policies to comply with treaty obligations. General Comment No 2 is invaluable in educating all stakeholders-including healthcare providers, lawyers, policymakers, and judicial officers at the domestic level-about pertinent jurisprudence. Civil society and human rights advocates can use the General Comment to render the state accountable for failure to implement its treaty obligations.

  6. Impact of regional climate change on human health.

    PubMed

    Patz, Jonathan A; Campbell-Lendrum, Diarmid; Holloway, Tracey; Foley, Jonathan A

    2005-11-17

    The World Health Organisation estimates that the warming and precipitation trends due to anthropogenic climate change of the past 30 years already claim over 150,000 lives annually. Many prevalent human diseases are linked to climate fluctuations, from cardiovascular mortality and respiratory illnesses due to heatwaves, to altered transmission of infectious diseases and malnutrition from crop failures. Uncertainty remains in attributing the expansion or resurgence of diseases to climate change, owing to lack of long-term, high-quality data sets as well as the large influence of socio-economic factors and changes in immunity and drug resistance. Here we review the growing evidence that climate-health relationships pose increasing health risks under future projections of climate change and that the warming trend over recent decades has already contributed to increased morbidity and mortality in many regions of the world. Potentially vulnerable regions include the temperate latitudes, which are projected to warm disproportionately, the regions around the Pacific and Indian oceans that are currently subjected to large rainfall variability due to the El Niño/Southern Oscillation sub-Saharan Africa and sprawling cities where the urban heat island effect could intensify extreme climatic events.

  7. Impact of regional climate change on human health

    NASA Astrophysics Data System (ADS)

    Patz, Jonathan A.; Campbell-Lendrum, Diarmid; Holloway, Tracey; Foley, Jonathan A.

    2005-11-01

    The World Health Organisation estimates that the warming and precipitation trends due to anthropogenic climate change of the past 30years already claim over 150,000 lives annually. Many prevalent human diseases are linked to climate fluctuations, from cardiovascular mortality and respiratory illnesses due to heatwaves, to altered transmission of infectious diseases and malnutrition from crop failures. Uncertainty remains in attributing the expansion or resurgence of diseases to climate change, owing to lack of long-term, high-quality data sets as well as the large influence of socio-economic factors and changes in immunity and drug resistance. Here we review the growing evidence that climate-health relationships pose increasing health risks under future projections of climate change and that the warming trend over recent decades has already contributed to increased morbidity and mortality in many regions of the world. Potentially vulnerable regions include the temperate latitudes, which are projected to warm disproportionately, the regions around the Pacific and Indian oceans that are currently subjected to large rainfall variability due to the El Niño/Southern Oscillation sub-Saharan Africa and sprawling cities where the urban heat island effect could intensify extreme climatic events.

  8. Human rights, mental illness, and HIV: the Luthando Neropsychiatric HIV Clinic in Soweto, South Africa.

    PubMed

    Jonsson, Greg; Furin, Jennifer; Jeenah, Fatema; Moosa, M Y; Sivepersad, Reshmi; Kalafatis, Fran; Schoeman, Janine

    2011-12-15

    HIV is the leading infectious killer of adults in the world today and a majority of persons with HIV live in southern Africa. Mental illness is common among patients with HIV. Persons with HIV and mental illness, however, are often denied access to HIV treatment for a variety of reasons, including presumed non-adherence, potential drug interactions, and lack of coordinated care. The exclusion of the mentally ill from HIV care is a concerning human rights issue. This paper discusses some of the human rights issues in the care of patients with mental illness and HIV and describes a successful model for integrated care developed at the Luthando Neuropsychiatric HIV Clinic in Soweto, South Africa. The Luthando clinic has provided care to more than 500 patients and has been shown to be a successful model for other programs to improve HIV care among the mentally ill.

  9. [Conjonctival human myiasis by Oestrus ovis in Northern Africa].

    PubMed

    Dedet, J-P

    2011-12-01

    Following the publication of a paper on Conjonctival human myiasis by Oestrus ovis in southern Tunisia by Anane and Ben Hssine (Bull Soc Pathol Exot (2010) 103(5):299-304), the author reminds that the discovery of this disease was made in Algeria, in 1907 by Edmond and Etienne Sergent.

  10. The Impact of Human Conflict on the Genetics of Mastomys natalensis and Lassa Virus in West Africa

    PubMed Central

    Denys, Christiane; ter Meulen, Jan; Wirth, Thierry

    2012-01-01

    Environmental changes have been shown to play an important role in the emergence of new human diseases of zoonotic origin. The contribution of social factors to their spread, especially conflicts followed by mass movement of populations, has not been extensively investigated. Here we reveal the effects of civil war on the phylogeography of a zoonotic emerging infectious disease by concomitantly studying the population structure, evolution and demography of Lassa virus and its natural reservoir, the rodent Mastomys natalensis, in Guinea, West Africa. Analysis of nucleoprotein gene sequences enabled us to reconstruct the evolutionary history of Lassa virus, which appeared 750 to 900 years ago in Nigeria and only recently spread across western Africa (170 years ago). Bayesian demographic inferences revealed that both the host and the virus populations have gone recently through severe genetic bottlenecks. The timing of these events matches civil war-related mass movements of refugees and accompanying environmental degradation. Forest and habitat destruction and human predation of the natural reservoir are likely explanations for the sharp decline observed in the rodent populations, the consequent virus population decline, and the coincident increased incidence of Lassa fever in these regions. Interestingly, we were also able to detect a similar pattern in Nigeria coinciding with the Biafra war. Our findings show that anthropogenic factors may profoundly impact the population genetics of a virus and its reservoir within the context of an emerging infectious disease. PMID:22615894

  11. The impact of human conflict on the genetics of Mastomys natalensis and Lassa virus in West Africa.

    PubMed

    Lalis, Aude; Leblois, Raphaël; Lecompte, Emilie; Denys, Christiane; Ter Meulen, Jan; Wirth, Thierry

    2012-01-01

    Environmental changes have been shown to play an important role in the emergence of new human diseases of zoonotic origin. The contribution of social factors to their spread, especially conflicts followed by mass movement of populations, has not been extensively investigated. Here we reveal the effects of civil war on the phylogeography of a zoonotic emerging infectious disease by concomitantly studying the population structure, evolution and demography of Lassa virus and its natural reservoir, the rodent Mastomys natalensis, in Guinea, West Africa. Analysis of nucleoprotein gene sequences enabled us to reconstruct the evolutionary history of Lassa virus, which appeared 750 to 900 years ago in Nigeria and only recently spread across western Africa (170 years ago). Bayesian demographic inferences revealed that both the host and the virus populations have gone recently through severe genetic bottlenecks. The timing of these events matches civil war-related mass movements of refugees and accompanying environmental degradation. Forest and habitat destruction and human predation of the natural reservoir are likely explanations for the sharp decline observed in the rodent populations, the consequent virus population decline, and the coincident increased incidence of Lassa fever in these regions. Interestingly, we were also able to detect a similar pattern in Nigeria coinciding with the Biafra war. Our findings show that anthropogenic factors may profoundly impact the population genetics of a virus and its reservoir within the context of an emerging infectious disease.

  12. Plan for supporting natural resources management in sub-Saharan Africa: Regional environmental strategy for the Africa bureau

    SciTech Connect

    Not Available

    1992-05-01

    USAID's plan for combatting environmental degradation in sub-Saharan Africa through natural resource management (NRM) is presented. USAID will focus its efforts on two problem areas: soil degradation due to unsustainable agricultural practices, and loss of tropical forests and other critical habitats. The subregions targeted are: arid and semi-arid tropics, tropical highlands, the country of Madagascar, and the humid tropical forest of the Congo Basin. The plan divides African countries into three categories. In Category I countries, USAID would implement comprehensive programs. Programs in Category II countries would focus more limited resources on a single technical priority. Category III countries generally have only small humanitarian and or political programs, and will not undertake bilateral NRM programs. Annexes include a detailed framework for organizing country NRM programs.

  13. United Nations Human and Financial Resources for Peacekeeping in Africa

    DTIC Science & Technology

    1994-06-01

    date of proclamation of the cease-fire and will finish when the results of the referendum are declared. As soon as the cease-fire is declared, MINURSO...regional organization, as envisaged in Chapter VII of the Charter." [Ref. 14] On 25 July 1993, a meeting was held in Cotonou (Benin) to establish a new...Abass Bundu (Executive Secretary of ECOWAS), and the leaders of the fighting factions. The Cotonou Agreement was formulated with a clear framework drawn

  14. Ground Truth, Magnitude Calibration, and Regional Phase Propagation and Detection in the Middle East and the Horn of Africa

    DTIC Science & Technology

    2008-09-01

    Iranian Plateau, Zagros Mountains, Arabian Peninsula, Turkish Plateau, Gulf of Aqaba, Dead Sea Rift) and the Horn of Africa (including the northern part...the Arabian Peninsula. In the first part of this project, seismograms from earthquakes in the Zagros Mountains recorded at regional distances have...algorithm and forward modeling of teleseismic depth phases. Early studies of the distribution of seismicity in the Zagros region found evidence for

  15. Hepatitis A virus in the Middle East and North Africa region: a new challenge.

    PubMed

    Melhem, N M; Talhouk, R; Rachidi, H; Ramia, S

    2014-01-01

    During the past three decades, a gradual shift in the age of infection with hepatitis A virus (HAV) from early childhood to adulthood has been observed. There is a general lack of updated data on HAV burden of disease, incidence and age-specific seroprevalence in countries of the Middle East and North Africa (MENA) region. The aim of this article is to review the published data on anti-HAV seroprevalence, an important tool to monitor infections rates, in countries of the MENA region and associated risk factors including water and socioeconomic data when available. Data on anti-HAV seroprevalence were found for 12 of 25 MENA countries. We show that MENA countries, similar to other areas in the world, have a clear shift in HAV incidence with a decline among young age groups and an increase among adults and older individuals. This would likely be associated with increased morbidity and increased risks of outbreaks among younger age groups. Consequently, the continuous surveillance of hepatitis A cases and the inclusion of hepatitis A vaccine in the expanded immunization programmes are needed in countries of the MENA.

  16. Lightning fatalities in the Transkei sub-region of South Africa.

    PubMed

    Meel, B L

    2007-04-01

    Lightning is a particularly unsettling product of bad weather. It kills more people than other natural disasters such as floods, hurricanes, and tornadoes, but, because lightning usually kills people one at a time, it tends to be an underrated hazard. High risk groups are uneducated, unsheltered and rural people. This study was carried out to determine the incidence of lightning fatalities in the Transkei sub-region. It is a review of records between 1993 and 2004 from the medico-legal autopsies at Umtata General Hospital (UGH). During the study period there were 10,860 autopsies performed on those who died of trauma and other unnatural circumstances which included 151 (1.4%) lightning fatalities. This represents 0.31 deaths per million per year. The highest (0.5/million) was in 1999, and the lowest (0.13/million) in 1997. The age of the victims ranged from 1 to 82 years, with a mean of 22 years. Males and females were almost equally represented (50%). The highest number of deaths (26.5%) was in the age group of 11 to 20 years, and the lowest number (2.7%) in the age group of 70+ years. There is a high incidence of lightning fatalities in the Transkei sub-region of South Africa. People need to be educated to disregard the myths of lightning strike.

  17. Groundwater arsenic contamination in Burkina Faso, West Africa: Predicting and verifying regions at risk.

    PubMed

    Bretzler, Anja; Lalanne, Franck; Nikiema, Julien; Podgorski, Joel; Pfenninger, Numa; Berg, Michael; Schirmer, Mario

    2017-04-15

    Arsenic contamination in groundwater from crystalline basement rocks in West Africa has only been documented in isolated areas and presents a serious health threat in a region already facing multiple challenges related to water quality and scarcity. We present a comprehensive dataset of arsenic concentrations from drinking water wells in rural Burkina Faso (n=1498), of which 14.6% are above 10μg/L. Included in this dataset are 269 new samples from regions where no published water quality data existed. We used multivariate logistic regression with arsenic measurements as calibration data and maps of geology and mineral deposits as independent predictor variables to create arsenic prediction models at concentration thresholds of 5, 10 and 50μg/L. These hazard maps delineate areas vulnerable to groundwater arsenic contamination in Burkina Faso. Bedrock composed of schists and volcanic rocks of the Birimian formation, potentially harbouring arsenic-containing sulphide minerals, has the highest probability of yielding groundwater arsenic concentrations >10μg/L. Combined with population density estimates, the arsenic prediction models indicate that ~560,000 people are potentially exposed to arsenic-contaminated groundwater in Burkina Faso. The same arsenic-bearing geological formations that are positive predictors for elevated arsenic concentrations in Burkina Faso also exist in neighbouring countries such as Mali, Ghana and Ivory Coast. This study's results are thus of transboundary relevance and can act as a trigger for targeted water quality surveys and mitigation efforts.

  18. Y-chromosome analysis in Egypt suggests a genetic regional continuity in Northeastern Africa.

    PubMed

    Manni, Franz; Leonardi, Pascal; Barakat, Abdelhamid; Rouba, Hassan; Heyer, Evelyne; Klintschar, Michael; McElreavey, Ken; Quintana-Murci, Lluís

    2002-10-01

    The geographic location of Egypt, at the interface between North Africa, the Middle East, and southern Europe, prompted us to investigate the genetic diversity of this population and its relationship with neighboring populations. To assess the extent to which the modern Egyptian population reflects this intermediate geographic position, ten Unique Event Polymorphisms (UEPs), mapping to the nonrecombining portion of the Y chromosome, have been typed in 164 Y chromosomes from three North African populations. The analysis of these binary markers, which define 11 Y-chromosome lineages, were used to determine the haplogroup frequencies in Egyptians, Moroccan Arabs, and Moroccan Berbers and thereby define the Y-chromosome background in these regions. Pairwise comparisons with a set of 15 different populations from neighboring European, North African, and Middle Eastern populations and geographic analysis showed the absence of any significant genetic barrier in the eastern part of the Mediterranean area, suggesting that genetic variation and gene flow in this area follow the "isolation-by-distance" model. These results are in sharp contrast with the observation of a strong north-south genetic barrier in the western Mediterranean basin, defined by the Gibraltar Strait. Thus, the Y-chromosome gene pool in the modern Egyptian population reflects a mixture of European, Middle Eastern, and African characteristics, highlighting the importance of ancient and recent migration waves, followed by gene flow, in the region.

  19. Capacity Building for Disaster Management in Vulnerable Regions of Africa: Implementing an Operational Flood Warming System in Lake Victoria

    NASA Astrophysics Data System (ADS)

    Hong, Y.; Li, L.; Adler, R.; Policelli, F.

    2008-12-01

    NASA Applied Science program has partnered with USAID and The Regional Centre for Mapping of Resources for Development (RCMRD) in Africa to implement an operational flood warning system for East Africa, SERVIR-Africa project. The project seeks to take advantage of remote sensing information as an alternative and supplemental to ground-based observation in order to preserve the spatial extent of flood hazards. The recently available and virtually uninterrupted supply of satellite-based rainfall estimates is increasingly becoming a cost-effective data source for flood prediction in many under-gauged regions around the world. Our initial focus aims to provide an operational flood warning system for Lake Victoria, a flood-prone region home to 30 million people. The key datasets enabling the development of a distributed hydrological model in Africa include TRMM-based Multi-satellite Precipitation Analysis (TMPA), digital elevation data from the Shuttle Radar Topography Mission (SRTM) mission, HydroSHEDS hydrological products, MODIS Land cover, and soil parameters provided by FAO. This research focuses on evaluation and integration the TMPA Real- Time product into an online operational flood prediction system. We will also identify the optimal calibration strategy for satellite rainfall data into real-time hydrological modeling, one current knowledge gap that has remained relatively unexplored. Early results demonstrate this flood modeling system is useful decision- support tool for governmental officials and international aid organizations to better quantify flood impacts and extent of hazard risk, as well as more expediently respond to flood emergencies.

  20. Evaluating Spatial Interaction Models for Regional Mobility in Sub-Saharan Africa

    PubMed Central

    Wesolowski, Amy; O’Meara, Wendy Prudhomme; Eagle, Nathan; Tatem, Andrew J.; Buckee, Caroline O.

    2015-01-01

    Simple spatial interaction models of human mobility based on physical laws have been used extensively in the social, biological, and physical sciences, and in the study of the human dynamics underlying the spread of disease. Recent analyses of commuting patterns and travel behavior in high-income countries have led to the suggestion that these models are highly generalizable, and as a result, gravity and radiation models have become standard tools for describing population mobility dynamics for infectious disease epidemiology. Communities in Sub-Saharan Africa may not conform to these models, however; physical accessibility, availability of transport, and cost of travel between locations may be variable and severely constrained compared to high-income settings, informal labor movements rather than regular commuting patterns are often the norm, and the rise of mega-cities across the continent has important implications for travel between rural and urban areas. Here, we first review how infectious disease frameworks incorporate human mobility on different spatial scales and use anonymous mobile phone data from nearly 15 million individuals to analyze the spatiotemporal dynamics of the Kenyan population. We find that gravity and radiation models fail in systematic ways to capture human mobility measured by mobile phones; both severely overestimate the spatial spread of travel and perform poorly in rural areas, but each exhibits different characteristic patterns of failure with respect to routes and volumes of travel. Thus, infectious disease frameworks that rely on spatial interaction models are likely to misrepresent population dynamics important for the spread of disease in many African populations. PMID:26158274

  1. Geopotential field anomalies and regional tectonic features - two case studies: southern Africa and Germany

    NASA Astrophysics Data System (ADS)

    Korte, Monika; Mandea, Mioara

    2016-05-01

    Maps of magnetic and gravity field anomalies provide information about physical properties of the Earth's crust and upper mantle, helpful in understanding geological conditions and tectonic structures. Depending on data availability, whether from the ground, airborne, or from satellites, potential field anomaly maps contain information on different ranges of spatial wavelengths, roughly corresponding to sources at different depths. Focussing on magnetic data, we compare amplitudes and characteristics of anomalies from maps based on various available data and as measured at geomagnetic repeat stations. Two cases are investigated: southern Africa, characterized by geologically old cratons and strong magnetic anomalies, and the smaller region of Germany with much younger crust and weaker anomalies. Estimating lithospheric magnetic anomaly values from the ground stations' time series (repeat station crustal biases) reveals magnetospheric field contributions causing time-varying offsets of several nT in the results. Similar influences might be one source of discrepancy when merging anomaly maps from different epochs. Moreover, we take advantage of recently developed satellite potential field models and compare magnetic and gravity gradient anomalies of ˜ 200 km resolution. Density and magnetization represent independent rock properties and thus provide complementary information on compositional and structural changes. Comparing short- and long-wavelength anomalies and the correlation of rather large-scale magnetic and gravity anomalies, and relating them to known lithospheric structures, we generally find a better agreement in the southern African region than the German region. This probably indicates stronger concordance between near-surface (down to at most a few km) and deeper (several kilometres down to Curie depth) structures in the former area, which can be seen to agree with a thicker lithosphere and a lower heat flux reported in the literature for the southern

  2. Impact of land cover characterization on regional climate modeling over West Africa

    NASA Astrophysics Data System (ADS)

    Sylla, Mouhamadou Bamba; Pal, Jeremy S.; Wang, Guiling L.; Lawrence, Peter J.

    2016-01-01

    The impact of high resolution modern vegetation cover on the West African climate is examined using the International Centre for Theoretical Physics Regional Climate Model implementing the NCAR Community Land Model. Two high resolution 25 km long-term simulations driven by the output from a coarser 50-km resolution simulation are performed for the period 1998-2010. One high resolution simulation uses an earlier and coarser-resolution version of plant functional type distribution and leaf area index, while the other uses a more recent, higher-quality, and finer-resolution version of the data. The results indicate that the new land cover distribution substantially alters the distribution of temperature with warming in Central Nigeria, northern Gulf of Guinea and part of the Sahel due to the replacement of C4 grass with corn; and cooling along the coastlines of the Gulf of Guinea and in Central Africa due to the replacement of C4 grass with tropical broadleaf evergreen trees. Changes in latent heat flux appear to be largely responsible for these temperature changes with a net decrease (increase) in regions of warming (cooling). The improved land cover distribution also results in a wetter monsoon season. The presence of corn tends to favor larger precipitation amounts via more intense events, while the presence of tropical broadleaf evergreen trees tends to favor the occurrence of both more intense and more frequent events. The wetter conditions appear to be sustained via (1) an enhanced soil moisture feedback; and (2) elevated moisture transport due to increased low-level convergence in regions south of 10N where the most substantial land cover differences are present. Overall the changes induced by the improved vegetation cover improve, to some extent, the performance of the high resolution regional climate model in simulating the main West African summer monsoon features.

  3. Human Heredity and Health (H3) in Africa Kidney Disease Research Network: A Focus on Methods in Sub-Saharan Africa.

    PubMed

    Osafo, Charlotte; Raji, Yemi Raheem; Burke, David; Tayo, Bamidele O; Tiffin, Nicki; Moxey-Mims, Marva M; Rasooly, Rebekah S; Kimmel, Paul L; Ojo, Akinlolu; Adu, Dwomoa; Parekh, Rulan S

    2015-12-07

    CKD affects an estimated 14% of adults in sub-Saharan Africa, but very little research has been done on the cause, progression, and prevention of CKD there. As part of the Human Heredity and Health in Africa (H3Africa) Consortium, the H3Africa Kidney Disease Research Network was established to study prevalent forms of kidney disease in sub-Saharan Africa and increase the capacity for genetics and genomics research. The study is performing comprehensive phenotypic characterization and analyzing environmental and genetic factors from nine clinical centers in four African countries (Ghana, Nigeria, Ethiopia, and Kenya) over a 5-year period. Approximately 4000 participants with specified kidney disease diagnoses and 4000 control participants will be enrolled in the four African countries. In addition, approximately 50 families with hereditary glomerular disease will be enrolled. The study includes both pediatric and adult participants age <1 to 74 years across a broad spectrum of kidney diseases secondary to hypertension-attributed nephropathy, diabetes, HIV infection, sickle cell disease, biopsy-proven glomerular disease, and CKD of unknown origin. Clinical and demographic data with biospecimens are collected to assess clinical, biochemical, and genetic markers of kidney disease. As of March 2015, a total of 3499 patients and controls have been recruited and 1897 had complete entry data for analysis. Slightly more than half (50.2%) of the cohort is female. Initial quality control of clinical data collection and of biosample and DNA analysis is satisfactory, demonstrating that a clinical research infrastructure can be successfully established in Africa. This study will provide clinical, biochemical, and genotypic data that will greatly increase the understanding of CKD in sub-Saharan Africa.

  4. Human Heredity and Health (H3) in Africa Kidney Disease Research Network: A Focus on Methods in Sub-Saharan Africa

    PubMed Central

    Osafo, Charlotte; Raji, Yemi Raheem; Burke, David; Tayo, Bamidele O.; Tiffin, Nicki; Moxey-Mims, Marva M.; Rasooly, Rebekah S.; Kimmel, Paul L.; Ojo, Akinlolu; Parekh, Rulan S.

    2015-01-01

    CKD affects an estimated 14% of adults in sub-Saharan Africa, but very little research has been done on the cause, progression, and prevention of CKD there. As part of the Human Heredity and Health in Africa (H3Africa) Consortium, the H3Africa Kidney Disease Research Network was established to study prevalent forms of kidney disease in sub-Saharan Africa and increase the capacity for genetics and genomics research. The study is performing comprehensive phenotypic characterization and analyzing environmental and genetic factors from nine clinical centers in four African countries (Ghana, Nigeria, Ethiopia, and Kenya) over a 5-year period. Approximately 4000 participants with specified kidney disease diagnoses and 4000 control participants will be enrolled in the four African countries. In addition, approximately 50 families with hereditary glomerular disease will be enrolled. The study includes both pediatric and adult participants age <1 to 74 years across a broad spectrum of kidney diseases secondary to hypertension-attributed nephropathy, diabetes, HIV infection, sickle cell disease, biopsy-proven glomerular disease, and CKD of unknown origin. Clinical and demographic data with biospecimens are collected to assess clinical, biochemical, and genetic markers of kidney disease. As of March 2015, a total of 3499 patients and controls have been recruited and 1897 had complete entry data for analysis. Slightly more than half (50.2%) of the cohort is female. Initial quality control of clinical data collection and of biosample and DNA analysis is satisfactory, demonstrating that a clinical research infrastructure can be successfully established in Africa. This study will provide clinical, biochemical, and genotypic data that will greatly increase the understanding of CKD in sub-Saharan Africa. PMID:26138261

  5. High-temperature environments of human evolution in East Africa based on bond ordering in paleosol carbonates

    PubMed Central

    Passey, Benjamin H.; Levin, Naomi E.; Cerling, Thure E.; Brown, Francis H.; Eiler, John M.

    2010-01-01

    Many important hominid-bearing fossil localities in East Africa are in regions that are extremely hot and dry. Although humans are well adapted to such conditions, it has been inferred that East African environments were cooler or more wooded during the Pliocene and Pleistocene when this region was a central stage of human evolution. Here we show that the Turkana Basin, Kenya—today one of the hottest places on Earth—has been continually hot during the past 4 million years. The distribution of 13C-18O bonds in paleosol carbonates indicates that soil temperatures during periods of carbonate formation were typically above 30 °C and often in excess of 35 °C. Similar soil temperatures are observed today in the Turkana Basin and reflect high air temperatures combined with solar heating of the soil surface. These results are specific to periods of soil carbonate formation, and we suggest that such periods composed a large fraction of integrated time in the Turkana Basin. If correct, this interpretation has implications for human thermophysiology and implies a long-standing human association with marginal environments. PMID:20534500

  6. Towards an automated monitoring of human settlements in South Africa using high resolution SPOT satellite imagery

    NASA Astrophysics Data System (ADS)

    Kemper, T.; Mudau, N.; Mangara, P.; Pesaresi, M.

    2015-04-01

    Urban areas in sub-Saharan Africa are growing at an unprecedented pace. Much of this growth is taking place in informal settlements. In South Africa more than 10% of the population live in urban informal settlements. South Africa has established a National Informal Settlement Development Programme (NUSP) to respond to these challenges. This programme is designed to support the National Department of Human Settlement (NDHS) in its implementation of the Upgrading Informal Settlements Programme (UISP) with the objective of eventually upgrading all informal settlements in the country. Currently, the NDHS does not have access to an updated national dataset captured at the same scale using source data that can be used to understand the status of informal settlements in the country. This pilot study is developing a fully automated workflow for the wall-to-wall processing of SPOT-5 satellite imagery of South Africa. The workflow includes an automatic image information extraction based on multiscale textural and morphological image features extraction. The advanced image feature compression and optimization together with innovative learning and classification techniques allow a processing of the SPOT-5 images using the Landsat-based National Land Cover (NLC) of South Africa from the year 2000 as low-resolution thematic reference layers as. The workflow was tested on 42 SPOT scenes based on a stratified sampling. The derived building information was validated against a visually interpreted building point data set and produced an accuracy of 97 per cent. Given this positive result, is planned to process the most recent wall-to-wall coverage as well as the archived imagery available since 2007 in the near future.

  7. Climatic controls on ecosystem resilience: Postfire regeneration in the Cape Floristic Region of South Africa.

    PubMed

    Wilson, Adam M; Latimer, Andrew M; Silander, John A

    2015-07-21

    Conservation of biodiversity and natural resources in a changing climate requires understanding what controls ecosystem resilience to disturbance. This understanding is especially important in the fire-prone Mediterranean systems of the world. The fire frequency in these systems is sensitive to climate, and recent climate change has resulted in more frequent fires over the last few decades. However, the sensitivity of postfire recovery and biomass/fuel load accumulation to climate is less well understood than fire frequency despite its importance in driving the fire regime. In this study, we develop a hierarchical statistical framework to model postfire ecosystem recovery using satellite-derived observations of vegetation as a function of stand age, topography, and climate. In the Cape Floristic Region (CFR) of South Africa, a fire-prone biodiversity hotspot, we found strong postfire recovery gradients associated with climate resulting in faster recovery in regions with higher soil fertility, minimum July (winter) temperature, and mean January (summer) precipitation. Projections using an ensemble of 11 downscaled Coupled Model Intercomparison Project Phase 5 (CMIP5) general circulation models (GCMs) suggest that warmer winter temperatures in 2080-2100 will encourage faster postfire recovery across the region, which could further increase fire frequency due to faster fuel accumulation. However, some models project decreasing precipitation in the western CFR, which would slow recovery rates there, likely reducing fire frequency through lack of fuel and potentially driving local biome shifts from fynbos shrubland to nonburning semidesert vegetation. This simple yet powerful approach to making inferences from large, remotely sensed datasets has potential for wide application to modeling ecosystem resilience in disturbance-prone ecosystems globally.

  8. Climatic controls on ecosystem resilience: Postfire regeneration in the Cape Floristic Region of South Africa

    PubMed Central

    Wilson, Adam M.; Latimer, Andrew M.; Silander, John A.

    2015-01-01

    Conservation of biodiversity and natural resources in a changing climate requires understanding what controls ecosystem resilience to disturbance. This understanding is especially important in the fire-prone Mediterranean systems of the world. The fire frequency in these systems is sensitive to climate, and recent climate change has resulted in more frequent fires over the last few decades. However, the sensitivity of postfire recovery and biomass/fuel load accumulation to climate is less well understood than fire frequency despite its importance in driving the fire regime. In this study, we develop a hierarchical statistical framework to model postfire ecosystem recovery using satellite-derived observations of vegetation as a function of stand age, topography, and climate. In the Cape Floristic Region (CFR) of South Africa, a fire-prone biodiversity hotspot, we found strong postfire recovery gradients associated with climate resulting in faster recovery in regions with higher soil fertility, minimum July (winter) temperature, and mean January (summer) precipitation. Projections using an ensemble of 11 downscaled Coupled Model Intercomparison Project Phase 5 (CMIP5) general circulation models (GCMs) suggest that warmer winter temperatures in 2080–2100 will encourage faster postfire recovery across the region, which could further increase fire frequency due to faster fuel accumulation. However, some models project decreasing precipitation in the western CFR, which would slow recovery rates there, likely reducing fire frequency through lack of fuel and potentially driving local biome shifts from fynbos shrubland to nonburning semidesert vegetation. This simple yet powerful approach to making inferences from large, remotely sensed datasets has potential for wide application to modeling ecosystem resilience in disturbance-prone ecosystems globally. PMID:26150521

  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. Distance from sub-Saharan Africa predicts mutational load in diverse human genomes.

    PubMed

    Henn, Brenna M; Botigué, Laura R; Peischl, Stephan; Dupanloup, Isabelle; Lipatov, Mikhail; Maples, Brian K; Martin, Alicia R; Musharoff, Shaila; Cann, Howard; Snyder, Michael P; Excoffier, Laurent; Kidd, Jeffrey M; Bustamante, Carlos D

    2016-01-26

    The Out-of-Africa (OOA) dispersal ∼ 50,000 y ago is characterized by a series of founder events as modern humans expanded into multiple continents. Population genetics theory predicts an increase of mutational load in populations undergoing serial founder effects during range expansions. To test this hypothesis, we have sequenced full genomes and high-coverage exomes from seven geographically divergent human populations from Namibia, Congo, Algeria, Pakistan, Cambodia, Siberia, and Mexico. We find that individual genomes vary modestly in the overall number of predicted deleterious alleles. We show via spatially explicit simulations that the observed distribution of deleterious allele frequencies is consistent with the OOA dispersal, particularly under a model where deleterious mutations are recessive. We conclude that there is a strong signal of purifying selection at conserved genomic positions within Africa, but that many predicted deleterious mutations have evolved as if they were neutral during the expansion out of Africa. Under a model where selection is inversely related to dominance, we show that OOA populations are likely to have a higher mutation load due to increased allele frequencies of nearly neutral variants that are recessive or partially recessive.

  11. Distance from sub-Saharan Africa predicts mutational load in diverse human genomes

    PubMed Central

    Henn, Brenna M.; Botigué, Laura R.; Peischl, Stephan; Dupanloup, Isabelle; Lipatov, Mikhail; Maples, Brian K.; Martin, Alicia R.; Musharoff, Shaila; Cann, Howard; Snyder, Michael P.; Excoffier, Laurent; Kidd, Jeffrey M.; Bustamante, Carlos D.

    2016-01-01

    The Out-of-Africa (OOA) dispersal ∼50,000 y ago is characterized by a series of founder events as modern humans expanded into multiple continents. Population genetics theory predicts an increase of mutational load in populations undergoing serial founder effects during range expansions. To test this hypothesis, we have sequenced full genomes and high-coverage exomes from seven geographically divergent human populations from Namibia, Congo, Algeria, Pakistan, Cambodia, Siberia, and Mexico. We find that individual genomes vary modestly in the overall number of predicted deleterious alleles. We show via spatially explicit simulations that the observed distribution of deleterious allele frequencies is consistent with the OOA dispersal, particularly under a model where deleterious mutations are recessive. We conclude that there is a strong signal of purifying selection at conserved genomic positions within Africa, but that many predicted deleterious mutations have evolved as if they were neutral during the expansion out of Africa. Under a model where selection is inversely related to dominance, we show that OOA populations are likely to have a higher mutation load due to increased allele frequencies of nearly neutral variants that are recessive or partially recessive. PMID:26712023

  12. Human rights and psychiatric care in Africa with particular reference to the Ethiopian situation.

    PubMed

    Alem, A

    2000-01-01

    Around 700 million people are estimated to live in the continent of Africa. The majority live far from health facilities and are short of basic supplies. Most African people believe that diseases in general, and mental illness in particular, are afflictions caused by supernatural evil forces. Traditional methods are preferred sources of help for health problems by most people in the continent. Modern psychiatric services are far from adequate. The available asylums are located in the capital cities and very few patients have access to them. There is no mental health legislation in some African countries. In Ethiopia, where the population is 55 million, there is only one mental hospital; and a total of 390 beds for psychiatric inpatients. There are 11 psychiatrists in the country. In the regions of the country, mental health services are provided by psychiatric nurses. Patients usually come to medical services having tried the available local means. Psychotic patients almost always are forced to come to the mental hospital by their families, friends, neighbours, work-mates (and very seldom by the police). Consent is not usually required to initiate treatment or admit such patients. Alleged offenders, who come to the hospital for assessment, stay in the same ward as other patients. Armed prison guards assigned to watch the prisoners also stay in the same room with the prisoners. Care providing procedures in Ethiopia do not seem to be in accordance with the declarations of human rights. However, in a country where the economy cannot provide its citizens with basic needs for survival, it is unlikely that the standard of mental health care will change much in the foreseeable future.

  13. Human amplification of drought-driven fire in tropical regions

    NASA Astrophysics Data System (ADS)

    Tosca, Michael

    2015-04-01

    The change in globally-measured radiative forcing from the pre-industrial to the present due to interactions between aerosol particles and cloud cover has the largest uncertainty of all anthropogenic factors. Uncertainties are largest in the tropics, where total cloud amount and incoming solar radiation are highest, and where 50% of all aerosol emissions originate from anthropogenic fire. It is well understood that interactions between smoke particles and cloud droplets modify cloud cover , which in turn affects climate, however, few studies have observed the temporal nature of aerosol-cloud interactions without the use of a model. Here we apply a novel approach to measure the effect of fire aerosols on convective clouds in tropical regions (Brazil, Africa and Indonesia) through a combination of remote sensing and meteorological data. We attribute a reduction in cloud fraction during periods of high aerosol optical depths to a smoke-driven inhibition of convection. We find that higher smoke burdens limit vertical updrafts, increase surface pressure, and increase low- level divergence-meteorological indicators of convective suppression. These results are corroborated by climate model simulations that show a smoke-driven increase in regionally averaged shortwave tropospheric heating and boundary layer stratification, and a decrease in vertical velocity and precipitation during the fire season (December-February). We then quantify the human response to decreased cloud cover using a combination of socioeconomic and climate data Our results suggest that, in tropical regions, anthropogenic fire initiates a positive feedback loop where increased aerosol emissions limit convection, dry the surface and enable increased fire activity via human ignition. This result has far-reaching implications for fire management and climate policy in emerging countries along the equator that utilize fire.

  14. Convergent adaptation of human lactase persistence in Africa and Europe.

    PubMed

    Tishkoff, Sarah A; Reed, Floyd A; Ranciaro, Alessia; Voight, Benjamin F; Babbitt, Courtney C; Silverman, Jesse S; Powell, Kweli; Mortensen, Holly M; Hirbo, Jibril B; Osman, Maha; Ibrahim, Muntaser; Omar, Sabah A; Lema, Godfrey; Nyambo, Thomas B; Ghori, Jilur; Bumpstead, Suzannah; Pritchard, Jonathan K; Wray, Gregory A; Deloukas, Panos

    2007-01-01

    A SNP in the gene encoding lactase (LCT) (C/T-13910) is associated with the ability to digest milk as adults (lactase persistence) in Europeans, but the genetic basis of lactase persistence in Africans was previously unknown. We conducted a genotype-phenotype association study in 470 Tanzanians, Kenyans and Sudanese and identified three SNPs (G/C-14010, T/G-13915 and C/G-13907) that are associated with lactase persistence and that have derived alleles that significantly enhance transcription from the LCT promoter in vitro. These SNPs originated on different haplotype backgrounds from the European C/T-13910 SNP and from each other. Genotyping across a 3-Mb region demonstrated haplotype homozygosity extending >2.0 Mb on chromosomes carrying C-14010, consistent with a selective sweep over the past approximately 7,000 years. These data provide a marked example of convergent evolution due to strong selective pressure resulting from shared cultural traits-animal domestication and adult milk consumption.

  15. Pleistocene sea-level fluctuations and human evolution on the southern coastal plain of South Africa

    NASA Astrophysics Data System (ADS)

    Compton, John S.

    2011-03-01

    Humans evolved in Africa, but where and how remain unclear. Here it is proposed that the southern coastal plain (SCP) of South Africa may have served as a geographical point of origin through periodic expansion and contraction (isolation) in response to glacial/interglacial changes in sea level and climate. During Pleistocene interglacial highstands when sea level was above -75 m human populations were isolated for periods of 360-3400 25-yr generations on the SCP by the rugged mountains of the Cape Fold Belt, climate and vegetation barriers. The SCP expands five-fold as sea level falls from -75 to -120 m during glacial maxima to form a continuous, unobstructed coastal plain accessible to the interior. An expanded and wet glacial SCP may have served as a refuge to humans and large migratory herds and resulted in the mixing of previously isolated groups. The expansive glacial SCP habitat abruptly contracts, by as much as one-third in 300 yr, during the rapid rise in sea level associated with glacial terminations. Rapid flooding may have increased population density and competition on the SCP to select for humans who expanded their diet to include marine resources or hunted large animals. Successful adaptations developed on an isolated SCP are predicted to widely disperse during glacial terminations when the SCP rapidly contracts or during the initial opening of the SCP in the transition to glacial maxima. The hypothesis that periodic expansion and contraction of the SCP, as well as the coastal plain of North Africa, contributed to the stepwise origin of our species over the last 800 thousand years (kyr) is evaluated by comparing the archeological, DNA and sea-level records. These records generally support the hypothesis, but more complete and well dated records are required to resolve the extent to which sea-level fluctuations influenced the complex history of human evolution.

  16. A new redfin species, Pseudobarbus skeltoni (Cyprinidae, Teleostei), from the Cape Floristic Region, South Africa.

    PubMed

    Chakona, Albert; Swartz, Ernst R

    2013-01-01

    A new cyprinid species, Pseudobarbus skeltoni sp. nov, is described from material recently collected in the upper Riviersonderend River (a major tributary of the Breede River system) and the Krom River (a tributary of the Molenaars River in the upper Breede River) in the Cape Floristic Region of South Africa. The new species is readily distinguished from congeners, except P. burgi and P burchelli, by having two pairs of prominent oral barbels. Pseudobarbus skeltoni can be distinguished from P. burgi and P burchelli by the following combination of characters: distinctive terminal (vs. subterminal) mouth in adults; mouth inferior in sub-adults and young adults of P skeltoni but lower lips are unretracted (vs. retracted) and lack a distinct cartilaginous plate; snout prominent; more slender head (head depth 64.2% of HL, vs. 70.1% of HL in P. burchelli and 74.1% of HL in P. burgi); and a longer head relative to standard length (30.5 % vs. 26.8% in P. burchelli and 25.8% in P. burgi). The new species attains the largest size of any Pseudobarbus. The restricted distribution and the small remaining population sizes of P skeltoni indicate that this species is highly threatened and requires immediate conservation attention.

  17. Topography as a driver of diversification in the Cape Floristic Region of South Africa.

    PubMed

    Verboom, G Anthony; Bergh, Nicola G; Haiden, Sarah A; Hoffmann, Vera; Britton, Matthew N

    2015-07-01

    The rugged topography of the Cape Floristic Region (CFR), South Africa, is frequently invoked to explain the spectacular radiation of the Cape flora, but the mechanisms involved remain unclear. Where recent authors emphasize the importance of elevation gradients as stimuli for ecological speciation, earlier workers stressed the role of topography as an isolating mechanism, particularly in montane lineages. Using six Cape plant lineages, we tested whether elevation niches are phylogenetically conserved. We then assessed whether high-elevation species are more consistently range-restricted than low-elevation species, and whether high-elevation sisters show stronger range exclusivity (allopatry) and weaker ecological and phenotypic differentiation, suggestive of nonecological speciation. Elevation niches tend to be phylogenetically conserved. Also, high-elevation species are more consistently range-restricted than low-elevation species, potentially explaining the generally stronger range exclusivity of high-elevation sisters. While the high-elevation zone is less homogeneous ecologically, more data are required to demonstrate that high-elevation sister species show generally weaker ecological and phenotypic differentiation. Topographic complexity promotes geographical isolation at high elevations, thereby providing opportunities for nonecological, vicariant speciation. While recognizing the need for additional data, we suggest that the upland and lowland floras of the CFR may differ with regard to predominant speciation mode.

  18. IASI-derived Surface Temperature Under Dusty Conditions: Application to the West Africa Region.

    NASA Astrophysics Data System (ADS)

    Mechri, Rihab; Capelle, Virginie; Chedin, Alain

    2016-04-01

    Giving access to energy and water budgets, Surface Temperature (ST) is considered as a key variable for a wide range of applications in particular for meteorology and climatology. An accurate knowledge of this variable should significantly improve the monitoring of numerous atmospheric and surface processes as well as their interactions. Even-though satellite sensors bring ST global fields at different spatial and temporal scales, the accuracy of these products is still questionable especially over land or for complex atmospheric conditions (presence of clouds, of aerosols, etc.). At LMD, the ST is determined through the simultaneous "Look-up-Table" inversion of satellite METOP/IASI radiances in terms of Aerosol Optical Depth (AOD), dust layer mean altitude and surface temperature . The main aim of this work is to validate IASI ST product and to analyze its spatial and temporal variability, in particular in the presence of dust aerosols. This approach has been first applied to the West Africa region. The accuracy of this ST product will be assessed in terms of bias and standard deviation against ST products from ECMWF forecast, from other satellite products (MODIS AQUA/TERRA, AATSR,…) and from in-situ measurements for different periods ranging from July 2007 to today according to the availability of these validation data.

  19. Dilution effect in bovine tuberculosis: risk factors for regional disease occurrence in Africa.

    PubMed

    Huang, Zheng Y X; de Boer, Willem F; van Langevelde, Frank; Xu, Chi; Ben Jebara, Karim; Berlingieri, Francesco; Prins, Herbert H T

    2013-08-22

    Changes in host diversity have been postulated to influence the risk of infectious diseases, including both dilution and amplification effects. The dilution effect refers to a negative relationship between biodiversity and disease risk, whereas the amplification effect occurs when biodiversity increases disease risk. We tested these effects with an influential disease, bovine tuberculosis (BTB), which is widespread in many countries, causing severe economic losses. Based on the BTB outbreak data in cattle from 2005 to 2010, we also tested, using generalized linear mixed models, which other factors were associated with the regional BTB presence in cattle in Africa. The interdependencies of predictors and their correlations with BTB presence were examined using path analysis. Our results suggested a dilution effect, where increased mammal species richness was associated with reduced probability of BTB presence after adjustment for cattle density. In addition, our results also suggested that areas with BTB infection in the preceding year, higher cattle density and larger percentage of area occupied by African buffalo were more likely to report BTB outbreaks. Climatic variables only indirectly influenced the risk of BTB presence through their effects on cattle density and wildlife distribution. Since most studies investigating the role of wildlife species on BTB transmission only involve single-species analysis, more efforts are needed to better understand the effect of the structure of wildlife communities on BTB dynamics.

  20. Adherence To Malaria Prophylaxis Among Peace Corps Volunteers in the Africa Region, 2013

    PubMed Central

    Landman, Keren Z.; Tan, Kathrine R.; Arguin, Paul M.

    2016-01-01

    Background Although malaria can be prevented with prophylaxis, it is diagnosed in over 100 Africa-region Peace Corps Volunteers annually. This suggests that prophylaxis non-adherence is a problem in these non-immune travelers. Methods We investigated Volunteers’ knowledge, attitudes, and practices regarding prophylaxis using an internet-based survey during August 19–September 30, 2013. Adherence was defined as taking doxycycline or atovaquone-proguanil daily, or taking mefloquine doses no more than 8 days apart. Results The survey was sent to 3,248 Volunteers. Of 781 whose responses were analyzed, 514 (73%) reported adherence to prophylaxis. The most common reasons for non-adherence were forgetting (n=530, 90%); fear of long-term adverse effects (LTAEs; n=316, 54%); and experiencing adverse events that Volunteers attributed to prophylaxis (n=297, 51%). Two hundred fourteen (27%) Volunteers reported not worrying about malaria. On multivariate analysis controlling for sex and experiencing adverse events Volunteers attributed to prophylaxis, the factor most strongly associated with non-adherence was being prescribed mefloquine (OR 5.4, 95% confidence interval 3.2–9.0). Conclusions We found moderate adherence and a prevailing fear of LTAEs among Volunteers. Strategies to improve prophylaxis adherence may include medication reminders, increasing education about prophylaxis safety and malaria risk, and promoting prompt management of prophylaxis side effects. PMID:25534297

  1. The Menengai Tuff: A 36 ka widespread tephra and its chronological relevance to Late Pleistocene human evolution in East Africa

    NASA Astrophysics Data System (ADS)

    Blegen, Nick; Brown, Francis H.; Jicha, Brian R.; Binetti, Katie M.; Faith, J. Tyler; Ferraro, Joseph V.; Gathogo, Patrick N.; Richardson, Jonathan L.; Tryon, Christian A.

    2016-11-01

    The East African Rift preserves the world's richest Middle and Late Pleistocene (∼780-12 ka) geological, archaeological and paleontological archives relevant to the emergence of Homo sapiens. This region also provides unparalleled chronological control for many important sites through tephrochronology, the dating and correlation of volcanic ashes as widespread isochronous markers in the geological record. There are many well-characterized Pliocene-Early Pleistocene tephras that are widespread across East Africa. A comparable framework is lacking for the Middle and Late Pleistocene; a period characterized by spatially and temporally complex patterns of climate change, as well as the emergence of modern Homo sapiens and the dispersal of this species across and out of Africa. Unraveling relationships among these spatial and temporally complex phenomena requires a precise chronology. To this end we report the Menengai Tuff, a widespread volcanic ash produced by the large-scale caldera-forming eruption in Kenya and 40Ar/39Ar dated to 35.62 ± 0.26 ka. Geochemical characterization of 565 glass shards from 36 samples by wavelength-dispersive electron probe microanalysis show the Menengai Tuff was deposited over >115,000 km2 and is found in the Baringo, Chalbi, Elmenteita, Nakuru, Olorgesailie, Turkana, and Victoria basins, all of which preserve rich Late Pleistocene paleoenvironmental and archaeological archives. Correlation and dating of the Menengai Tuff demonstrate that it is the most widespread tephra and largest eruption currently known from the Late Pleistocene of East Africa. As such, it is a valuable marker in establishing a Late Pleistocene chronology for paleoclimatic, archeological, and paleontological records relevant to the study of human evolution.

  2. Hantaviruses in Africa.

    PubMed

    Witkowski, Peter T; Klempa, Boris; Ithete, Ndapewa L; Auste, Brita; Mfune, John K E; Hoveka, Julia; Matthee, Sonja; Preiser, Wolfgang; Kruger, Detlev H

    2014-07-17

    This paper summarizes the progress in the search for hantaviruses and hantavirus infections in Africa. After having collected molecular evidence of an indigenous African hantavirus in 2006, an intensive investigation for new hantaviruses has been started in small mammals. Various novel hantaviruses have been molecularly identified not only in rodents but also in shrews and bats. In addition, the first African hantavirus, Sangassou virus, has been isolated and functionally characterized in cell culture. Less is known about the ability of these hantaviruses to infect humans and to cause diseases. To date, no hantavirus genetic material could be amplified from patients' specimens collected in Africa. Serological studies in West Africa, based on a battery of screening and confirmatory assays, led to the detection of hantavirus antibodies in the human population and in patients with putative hantavirus disease. In addition to this overview, we present original data from seroepidemiological and field studies conducted in the Southern part of Africa. A human seroprevalence rate of 1.0% (n=1442) was detected in the South African Cape Region whereas no molecular evidence for the presence of hantavirus was found in 2500 small animals trapped in South Africa and Namibia.

  3. The 2014 Ebola virus outbreak in West Africa highlights no evidence of rapid evolution or adaptation to humans

    PubMed Central

    Li, Xingguang; Zai, Junjie; Liu, Haizhou; Feng, Yi; Li, Fan; Wei, Jing; Zou, Sen; Yuan, Zhiming; Shao, Yiming

    2016-01-01

    Following its immergence in December 2013, the recent Zaire Ebola virus (EBOV) outbreak in West Africa has spread and persisted for more than two years, making it the largest EBOV epidemic in both scale and geographical region to date. In this study, a total of 726 glycoprotein (GP) gene sequences of the EBOV full-length genome obtained from West Africa from the 2014 outbreak, combined with 30 from earlier outbreaks between 1976 and 2008 were used to investigate the genetic divergence, evolutionary history, population dynamics, and selection pressure of EBOV among distinct epidemic waves. Results from our dataset showed that no non-synonymous substitutions occurred on the GP gene coding sequences of EBOV that were likely to have affected protein structure or function in any way. Furthermore, the significantly different dN/dS ratios observed between the 2014 West African outbreak and earlier outbreaks were more likely due to the confounding presence of segregating polymorphisms. Our results highlight no robust evidence that the 2014 EBOV outbreak is fast-evolving and adapting to humans. Therefore, the unprecedented nature of the 2014 EBOV outbreak might be more likely related to non-virological elements, such as environmental and sociological factors. PMID:27767073

  4. H3ABioNet, a sustainable pan-African bioinformatics network for human heredity and health in Africa.

    PubMed

    Mulder, Nicola J; Adebiyi, Ezekiel; Alami, Raouf; Benkahla, Alia; Brandful, James; Doumbia, Seydou; Everett, Dean; Fadlelmola, Faisal M; Gaboun, Fatima; Gaseitsiwe, Simani; Ghazal, Hassan; Hazelhurst, Scott; Hide, Winston; Ibrahimi, Azeddine; Jaufeerally Fakim, Yasmina; Jongeneel, C Victor; Joubert, Fourie; Kassim, Samar; Kayondo, Jonathan; Kumuthini, Judit; Lyantagaye, Sylvester; Makani, Julie; Mansour Alzohairy, Ahmed; Masiga, Daniel; Moussa, Ahmed; Nash, Oyekanmi; Ouwe Missi Oukem-Boyer, Odile; Owusu-Dabo, Ellis; Panji, Sumir; Patterton, Hugh; Radouani, Fouzia; Sadki, Khalid; Seghrouchni, Fouad; Tastan Bishop, Özlem; Tiffin, Nicki; Ulenga, Nzovu

    2016-02-01

    The application of genomics technologies to medicine and biomedical research is increasing in popularity, made possible by new high-throughput genotyping and sequencing technologies and improved data analysis capabilities. Some of the greatest genetic diversity among humans, animals, plants, and microbiota occurs in Africa, yet genomic research outputs from the continent are limited. The Human Heredity and Health in Africa (H3Africa) initiative was established to drive the development of genomic research for human health in Africa, and through recognition of the critical role of bioinformatics in this process, spurred the establishment of H3ABioNet, a pan-African bioinformatics network for H3Africa. The limitations in bioinformatics capacity on the continent have been a major contributory factor to the lack of notable outputs in high-throughput biology research. Although pockets of high-quality bioinformatics teams have existed previously, the majority of research institutions lack experienced faculty who can train and supervise bioinformatics students. H3ABioNet aims to address this dire need, specifically in the area of human genetics and genomics, but knock-on effects are ensuring this extends to other areas of bioinformatics. Here, we describe the emergence of genomics research and the development of bioinformatics in Africa through H3ABioNet.

  5. H3ABioNet, a sustainable pan-African bioinformatics network for human heredity and health in Africa

    PubMed Central

    Mulder, Nicola J.; Adebiyi, Ezekiel; Alami, Raouf; Benkahla, Alia; Brandful, James; Doumbia, Seydou; Everett, Dean; Fadlelmola, Faisal M.; Gaboun, Fatima; Gaseitsiwe, Simani; Ghazal, Hassan; Hazelhurst, Scott; Hide, Winston; Ibrahimi, Azeddine; Jaufeerally Fakim, Yasmina; Jongeneel, C. Victor; Joubert, Fourie; Kassim, Samar; Kayondo, Jonathan; Kumuthini, Judit; Lyantagaye, Sylvester; Makani, Julie; Mansour Alzohairy, Ahmed; Masiga, Daniel; Moussa, Ahmed; Nash, Oyekanmi; Ouwe Missi Oukem-Boyer, Odile; Owusu-Dabo, Ellis; Panji, Sumir; Patterton, Hugh; Radouani, Fouzia; Sadki, Khalid; Seghrouchni, Fouad; Tastan Bishop, Özlem; Tiffin, Nicki; Ulenga, Nzovu

    2016-01-01

    The application of genomics technologies to medicine and biomedical research is increasing in popularity, made possible by new high-throughput genotyping and sequencing technologies and improved data analysis capabilities. Some of the greatest genetic diversity among humans, animals, plants, and microbiota occurs in Africa, yet genomic research outputs from the continent are limited. The Human Heredity and Health in Africa (H3Africa) initiative was established to drive the development of genomic research for human health in Africa, and through recognition of the critical role of bioinformatics in this process, spurred the establishment of H3ABioNet, a pan-African bioinformatics network for H3Africa. The limitations in bioinformatics capacity on the continent have been a major contributory factor to the lack of notable outputs in high-throughput biology research. Although pockets of high-quality bioinformatics teams have existed previously, the majority of research institutions lack experienced faculty who can train and supervise bioinformatics students. H3ABioNet aims to address this dire need, specifically in the area of human genetics and genomics, but knock-on effects are ensuring this extends to other areas of bioinformatics. Here, we describe the emergence of genomics research and the development of bioinformatics in Africa through H3ABioNet. PMID:26627985

  6. 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.

  7. Education and language: A human right for sustainable development in Africa

    NASA Astrophysics Data System (ADS)

    Babaci-Wilhite, Zehlia; Geo-JaJa, Macleans A.; Lou, Shizhou

    2012-10-01

    Pre-colonial Africa was neither an educationally nor a technologically unsophisticated continent. While education was an integral part of the culture, issues of language identification and standardisation which are subject to contentious debate today were insignificant. Children learned community knowledge and history by asking questions instead of being taught in a hegemonic alien language. This article argues that education and development should take place in a broader context of human rights, and explores the links between three areas often dealt with separately, namely: language, education and development. The authors of this paper demonstrate that changing the face of the multi-dimensionalities of poverty within societies is possible only when education is constructed in a rights perspective over the favoured colonial languages, which are not an integral part of the culture and resources of a community. The authors make a distinction between the right to education and rights in education, the latter of which are found to be more significant for the challenges Africa faces. It is argued here that the elements of Amartya Sen's "threshold" conditions for inclusion in human rights and self-development in education are essential, and that a more promising architecture of education would include what the authors term meta-narrative frameworks, i.e. interrelated policies. The authors contend that the neoliberal commodification of the knowledge sector has only exacerbated human rights and capabilities deprivation - which encompasses both human and income poverty.

  8. The Sahel Region of West Africa: Examples of Climate Analyses Motivated By Drought Management Needs

    NASA Astrophysics Data System (ADS)

    Ndiaye, O.; Ward, M. N.; Siebert, A. B.

    2011-12-01

    The Sahel is one of the most drought-prone regions in the world. This paper focuses on climate sources of drought, and some new analyses mostly driven by users needing climate information to help in drought management strategies. The Sahel region of West Africa is a transition zone between equatorial climate and vegetation to the south, and desert to the north. The climatology of the region is dominated by dry conditions for most of the year, with a single peak in rainfall during boreal summer. The seasonal rainfall total contains both interannual variability and substantial decadal to multidecadal variability (MDV). This brings climate analysis and drought management challenges across this range of timescales. The decline in rainfall from the wet decades of the 1950s and 60s to the dry decades of the 1970s and 80s has been well documented. In recent years, a moderate recovery has emerged, with seasonal totals in the period 1994-2010 significantly higher than the average rainfall 1970-1993. These MDV rainfall fluctuations have expression in large-scale sea-surface temperature fluctuations in all ocean basins, placing the changes in drought frequency within broader ocean-atmosphere climate fluctuation. We have evaluated the changing character of low seasonal rainfall total event frequencies in the Sahel region 1950-2010, highlighting the role of changes in the mean, variance and distribution shape of seasonal rainfall totals as the climate has shifted through the three observed phases. We also consider the extent to which updating climate normals in real-time can damp the bias in expected event frequency, an important issue for the feasibility of index insurance as a drought management tool in the presence of a changing climate. On the interannual timescale, a key factor long discussed for agriculture is the character of rainfall onset. An extended dry spell often occurs early in the rainy season before the crop is fully established, and this often leads to crop

  9. Mapping human dispersals into the Horn of Africa from Arabian Ice Age refugia using mitogenomes.

    PubMed

    Gandini, Francesca; Achilli, Alessandro; Pala, Maria; Bodner, Martin; Brandini, Stefania; Huber, Gabriela; Egyed, Balazs; Ferretti, Luca; Gómez-Carballa, Alberto; Salas, Antonio; Scozzari, Rosaria; Cruciani, Fulvio; Coppa, Alfredo; Parson, Walther; Semino, Ornella; Soares, Pedro; Torroni, Antonio; Richards, Martin B; Olivieri, Anna

    2016-05-05

    Rare mitochondrial lineages with relict distributions can sometimes be disproportionately informative about deep events in human prehistory. We have studied one such lineage, haplogroup R0a, which uniquely is most frequent in Arabia and the Horn of Africa, but is distributed much more widely, from Europe to India. We conclude that: (1) the lineage ancestral to R0a is more ancient than previously thought, with a relict distribution across the Mediterranean/Southwest Asia; (2) R0a has a much deeper presence in Arabia than previously thought, highlighting the role of at least one Pleistocene glacial refugium, perhaps on the Red Sea plains; (3) the main episode of dispersal into Eastern Africa, at least concerning maternal lineages, was at the end of the Late Glacial, due to major expansions from one or more refugia in Arabia; (4) there was likely a minor Late Glacial/early postglacial dispersal from Arabia through the Levant and into Europe, possibly alongside other lineages from a Levantine refugium; and (5) the presence of R0a in Southwest Arabia in the Holocene at the nexus of a trading network that developed after ~3 ka between Africa and the Indian Ocean led to some gene flow even further afield, into Iran, Pakistan and India.

  10. Mapping human dispersals into the Horn of Africa from Arabian Ice Age refugia using mitogenomes

    PubMed Central

    Gandini, Francesca; Achilli, Alessandro; Pala, Maria; Bodner, Martin; Brandini, Stefania; Huber, Gabriela; Egyed, Balazs; Ferretti, Luca; Gómez-Carballa, Alberto; Salas, Antonio; Scozzari, Rosaria; Cruciani, Fulvio; Coppa, Alfredo; Parson, Walther; Semino, Ornella; Soares, Pedro; Torroni, Antonio; Richards, Martin B.; Olivieri, Anna

    2016-01-01

    Rare mitochondrial lineages with relict distributions can sometimes be disproportionately informative about deep events in human prehistory. We have studied one such lineage, haplogroup R0a, which uniquely is most frequent in Arabia and the Horn of Africa, but is distributed much more widely, from Europe to India. We conclude that: (1) the lineage ancestral to R0a is more ancient than previously thought, with a relict distribution across the Mediterranean/Southwest Asia; (2) R0a has a much deeper presence in Arabia than previously thought, highlighting the role of at least one Pleistocene glacial refugium, perhaps on the Red Sea plains; (3) the main episode of dispersal into Eastern Africa, at least concerning maternal lineages, was at the end of the Late Glacial, due to major expansions from one or more refugia in Arabia; (4) there was likely a minor Late Glacial/early postglacial dispersal from Arabia through the Levant and into Europe, possibly alongside other lineages from a Levantine refugium; and (5) the presence of R0a in Southwest Arabia in the Holocene at the nexus of a trading network that developed after ~3 ka between Africa and the Indian Ocean led to some gene flow even further afield, into Iran, Pakistan and India. PMID:27146119

  11. A numerical modeling study of the coupled variability of Lake Victoria in eastern Africa and the regional climate

    NASA Astrophysics Data System (ADS)

    Song, Yi

    2000-12-01

    The objective of this investigation was to investigate and study the coupled atmosphere-lake climate system over the Lake Victoria basin, and determine the corresponding physical mechanisms that are involved. The primary research vehicle for the investigation is a fully coupled model of the regional climate of Eastern Africa and Lake Victoria which has been developed and applied in this study. The atmospheric component of the model is the NCAR Regional Climate Model (RegCM2). The results show that the bythemetry and geometry of the lake play a fundamental role in determining the climatology of Lake Victoria. There exists Kelvin-like waves in the thermocline trapped along the coast and they propagate clockwise around Lake Victoria with periodicity of about 30 days. Preliminary comparison of the coupled RegCM2-POM model simulation results with the observations indicates that the model produces more realistic lake surface temperatures (LST) and rainfall over and around the lake than the standard version of RegCM2 in which a simple one dimensional thermal diffusion lake model is used. Over Eastern Africa, the regional climate variability is significantly influenced by the circulation over the Lake Victoria basin. The interaction between the lake-land breeze and the prevailing northeasterly flow accounts for the asymmetry in the distribution of the diurnal rainfall variations and the southwestward movement of the dominant bands of divergence/convergence. During the 1982 El Nino when the averaged LST over the lake was higher than that during the normal year, the LST gradient was weakened along the SW-NE axis over the lake by the strong lake circulation. The hydrodynamics of the lake play an important role in determining the coupled variability of the lake circulation and the lake basin-wide climatic conditions. The potential climate change resulting from total clearing of the tropical rain forests in Africa was also investigated by the standard version of the NCAR CCM3

  12. Multiple Introductions and Recent Spread of the Emerging Human Pathogen Mycobacterium ulcerans across Africa

    PubMed Central

    Meehan, Conor J.; Eddyani, Miriam; Affolabi, Dissou; Phanzu, Delphin Mavinga; Eyangoh, Sara; Jordaens, Kurt; Portaels, Françoise; Mangas, Kirstie; Seemann, Torsten; Marsollier, Laurent; Marion, Estelle; Chauty, Annick; Landier, Jordi; Fontanet, Arnaud; Leirs, Herwig; Stinear, Timothy P.; de Jong, Bouke C.

    2017-01-01

    Buruli ulcer (BU) is an insidious neglected tropical disease. Cases are reported around the world but the rural regions of West and Central Africa are most affected. How BU is transmitted and spreads has remained a mystery, even though the causative agent, Mycobacterium ulcerans, has been known for more than 70 years. Here, using the tools of population genomics, we reconstruct the evolutionary history of M. ulcerans by comparing 165 isolates spanning 48 years and representing 11 endemic countries across Africa. The genetic diversity of African M. ulcerans was found to be restricted due to the bacterium’s slow substitution rate coupled with its relatively recent origin. We identified two specific M. ulcerans lineages within the African continent, and inferred that M. ulcerans lineage Mu_A1 existed in Africa for several hundreds of years, unlike lineage Mu_A2, which was introduced much more recently, approximately during the 19th century. Additionally, we observed that specific M. ulcerans epidemic Mu_A1 clones were introduced during the same time period in the three hydrological basins that were well covered in our panel. The estimated time span of the introduction events coincides with the Neo-imperialism period, during which time the European colonial powers divided the African continent among themselves. Using this temporal association, and in the absence of a known BU reservoir or—vector on the continent, we postulate that the so-called "Scramble for Africa" played a significant role in the spread of the disease across the continent. PMID:28137745

  13. Assessing the link between Atlantic Niño 1 and drought over West Africa using CORDEX regional climate models

    NASA Astrophysics Data System (ADS)

    Adeniyi, Mojisola Oluwayemisi; Dilau, Kabiru Alabi

    2016-12-01

    The skill of Coordinated Regional Climate Downscaling Experiment (CORDEX) models (ARPEGE, CCLM, HIRHAM, RACMO, REMO, PRECIS, RegCM3, RCA, WRF and CRCM) in simulating the climate (precipitation, temperature and drought) of West Africa is determined using a process-based metric. This is done by comparing the CORDEX models' simulated and observed correlation coefficients between Atlantic Niño Index 1 (ATLN1) and the climate over West Africa. Strong positive correlation is observed between ATLN1 and the climate parameters at the Guinea Coast (GC). The Atlantic Ocean has Niño behaviours through the ATLN indices which influence the climate of the tropics. Drought has distinct dipole structure of correlation with ATLN1 (negative at the Sahel); precipitation does not have distinct dipole structure of correlation, while temperature has almost a monopole correlation structure with ATLN1 over West Africa. The magnitude of the correlation increases with closeness to the equatorial eastern Atlantic. Correlations between ATLN1 and temperature are mostly stronger than those between ATLN1 and precipitation over the region. Most models have good performance over the GC, but ARPEGE has the highest skill at GC. The PRECIS is the most skilful over Savannah and RCA over Sahel. These models can be used to downscale the projected climate at the region of their highest skill.

  14. Precipitation recycling in West Africa - regional modeling, evaporation tagging and atmospheric water budget analysis

    NASA Astrophysics Data System (ADS)

    Arnault, Joel; Kunstmann, Harald; Knoche, Hans-Richard

    2015-04-01

    Many numerical studies have shown that the West African monsoon is highly sensitive to the state of the land surface. It is however questionable to which extend a local change of land surface properties would affect the local climate, especially with respect to precipitation. This issue is traditionally addressed with the concept of precipitation recycling, defined as the contribution of local surface evaporation to local precipitation. For this study the West African monsoon has been simulated with the Weather Research and Forecasting (WRF) model using explicit convection, for the domain (1°S-21°N, 18°W-14°E) at a spatial resolution of 10 km, for the period January-October 2013, and using ERA-Interim reanalyses as driving data. This WRF configuration has been selected for its ability to simulate monthly precipitation amounts and daily histograms close to TRMM (Tropical Rainfall Measuring Mission) data. In order to investigate precipitation recycling in this WRF simulation, surface evaporation tagging has been implemented in the WRF source code as well as the budget of total and tagged atmospheric water. Surface evaporation tagging consists in duplicating all water species and the respective prognostic equations in the source code. Then, tagged water species are set to zero at the lateral boundaries of the simulated domain (no inflow of tagged water vapor), and tagged surface evaporation is considered only in a specified region. All the source terms of the prognostic equations of total and tagged water species are finally saved in the outputs for the budget analysis. This allows quantifying the respective contribution of total and tagged atmospheric water to atmospheric precipitation processes. The WRF simulation with surface evaporation tagging and budgets has been conducted two times, first with a 100 km2 tagged region (11-12°N, 1-2°W), and second with a 1000 km2 tagged region (7-16°N, 6°W -3°E). In this presentation we will investigate hydro

  15. Orphans and Vulnerable Children Affected by Human Immunodeficiency Virus in Sub-Saharan Africa.

    PubMed

    Bryant, Malcolm; Beard, Jennifer

    2016-02-01

    In Sub-Saharan Africa, 15.1 million children have been orphaned because of human immunodeficiency virus (HIV). They face significant vulnerabilities, including stigma and discrimination, trauma and stress, illness, food insecurity, poverty, and difficulty accessing education. Millions of additional children who have living parents are vulnerable because their parents or other relatives are infected. This article reviews the current situation of orphans and vulnerable children, explores the underlying determinants of vulnerability and resilience, describes the response by the global community, and highlights the challenges as the HIV pandemic progresses through its fourth decade.

  16. Validation of the regional climate model MAR over the CORDEX Africa domain and comparison with other regional models using unpublished data set

    NASA Astrophysics Data System (ADS)

    Prignon, Maxime; Agosta, Cécile; Kittel, Christoph; Fettweis, Xavier; Michel, Erpicum

    2016-04-01

    In the framework of the CORDEX project, we have applied the regional model MAR over the Africa domain at a resolution of 50 km. ERA-Interim and NCEP-NCAR reanalysis have been used as 6 hourly forcing at the MAR boundaries over 1950-2015. While MAR was already been validated over the West Africa, it is the first time that MAR simulations are carried out at the scale of the whole continent. Unpublished daily measurements, covering the Sahel and more areas up South, with a large set of variables, are used as validation of MAR, other CORDEX-Africa RCMs and both reanalyses. Comparisons with the CRU and the ECA&D databases are also performed. The unpublished daily data set covers the period 1884-2006 and comes from 1460 stations. The measured variables are wind, evapotranspiration, relative humidity, insolation, rain, surface pressure, temperature, vapour pressure and visibility. It covers 23 countries: Algeria, Benin, Burkina, Canary Islands, Cap Verde, Central Africa, Chad, Congo, Ivory Coast, Gabon, Gambia, Ghana, Guinea, Guinea-Bissau, Mali, Mauritania, Morocco, Niger, Nigeria, Senegal, Sudan and Togo.

  17. Vegetation-climate feedback causes reduced precipitation in CMIP5 regional Earth system model simulation over Africa

    NASA Astrophysics Data System (ADS)

    Wu, Minchao; Smith, Benjamin; Schurgers, Guy; Lindström, Joe; Rummukainen, Markku; Samuelsson, Patrick

    2013-04-01

    Terrestrial ecosystems have been demonstrated to play a significant role within the climate system, amplifying or dampening climate change via biogeophysical and biogeochemical exchange with the atmosphere and vice versa (Cox et al. 2000; Betts et al. 2004). Africa is particularly vulnerable to climate change and studies of vegetation-climate feedback mechanisms on Africa are still limited. Our study is the first application of A coupled Earth system model at regional scale and resolution over Africa. We applied a coupled regional climate-vegetation model, RCA-GUESS (Smith et al. 2011), over the CORDEX Africa domain, forced by boundary conditions from a CanESM2 CMIP5 simulation under the RCP8.5 future climate scenario. The simulations were from 1961 to 2100 and covered the African continent at a horizontal grid spacing of 0.44°. RCA-GUESS simulates changes in the phenology, productivity, relative cover and population structure of up to eight plant function types (PFTs) in response to forcing from the climate part of the model. These vegetation changes feedback to simulated climate through dynamic adjustments in surface energy fluxes and surface properties. Changes in the net ecosystem-atmosphere carbon flux and its components net primary production (NPP), heterotrophic respiration and emissions from biomass burning were also simulated but do not feedback to climate in our model. Constant land cover was assumed. We compared simulations with and without vegetation feedback switched "on" to assess the influence of vegetation-climate feedback on simulated climate, vegetation and ecosystem carbon cycling. Both positive and negative warming feedbacks were identified in different parts of Africa. In the Sahel savannah zone near 15°N, reduced vegetation cover and productivity, and mortality caused by a deterioration of soil water conditions led to a positive warming feedback mediated by decreased evapotranspiration and increased sensible heat flux between vegetation and

  18. Modeling land-atmosphere interactions: the impact of deforestation in tropical Africa on the regional climate.

    NASA Astrophysics Data System (ADS)

    Akkermans, Tom; Lauwaet, Dirk; van Lipzig, Nicole

    2010-05-01

    Deforestation is generally seen as an alarming trend, especially in third world countries. This research focuses on the climatological impact of anthropogenic forest degradation in tropical Africa, a study area which has received relatively few attention. Building on previous studies, additional and new research methods are applied. A regional climate model (COSMO-CLM) will be used and coupled to a soil-vegetation-atmosphere transfer component (the Community Land Model). As this research just started, the poster presentation will give an overview of the project, which is described below. Firstly, the impact of overall deforestation estimates will be quantified by applying a spatial algorithm for different deforestation amounts, constrained by allocation rules. Secondly, this algorithm will also be used to investigate the impact of spatial deforestation patterns, e.g. concentrated versus dispersed logging. Thirdly, climate-vegetation feedbacks will be included in the model runs. Physiological effects of increased greenhouse gases on vegetation (e.g. reduction of stomatal conductance, hence decrease in transpiration) and dynamical vegetation cycles (e.g. reaction of leaf area index on dry spells and heat stress) are the focus of interest. Finally, the effect of land cover change on detailed atmospheric processes such as convective activity will be studied. The second as well as the fourth goal requires a substantial increase in spatial detail compared to current studies, which will be obtained by increasing the horizontal resolution (for the atmospheric model and for the land cover data) and making use of sub-grid flux calculations for energy and moisture. The impact of the above-mentioned elements will be quantified by comparing different model simulations. The overall climate forcing from land cover change will be compared with the forcing from greenhouse gases, which allows for quantifying their relative importance.

  19. The Hydroclimate of East Africa: Seasonal cycle, Decadal Variability, and Human-induced Climate Change

    NASA Astrophysics Data System (ADS)

    Yang, Wenchang

    cold east SST bias over the Indian Ocean contributes to the wet OND rainfall bias in East Africa. Finally, to understand the East African regional climate in the context of the broader tropical climate and circulation, zonal momentum balance of the tropical atmospheric circulation during the global monsoon mature months (January and July) are analyzed in three dimensions based on the ERA-Interim Re-Analysis. It is found that the dominant terms in the balance of the atmospheric boundary layer (ABL) in both months are the pressure gradient force, the Coriolis force and friction. The nonlinear advection term plays a significant role only in the Asian summer monsoon regions including off East Africa. In the upper troposphere, the pressure gradient force, the Coriolis force and nonlinear advection are the dominant terms. The transient eddy force and the residual force (which can be explained as convective momentum transfer over open oceans) are secondary yet can not be neglected near the equator. Zonal mean equatorial upper troposphere easterlies are maintained by the absolute angular momentum advection associated with the cross-equatorial Hadley circulation. Equatorial upper troposphere easterlies over the Asian monsoon regions are also controllled by the absolute angular momentum advection but are mainly maintained by the pressure gradient force in January. The equivalent linear Rayleigh friction, which is widely applied in simple tropical models, is calculated and the corresponding spatial distribution of local coefficient and damping time scale are estimated from the linear regression. It is found that the linear momentum model is in general capable of crudely describing the tropical atmospheric circulation dynamics yet the caveat should be kept in mind that the friction coefficient is not uniformly distributed and is even negative in some regions.

  20. WMO SDS-WAS NAMEE Regional Center: Towards continuous evaluation of dust models in Northern Africa

    NASA Astrophysics Data System (ADS)

    Basart, Sara; García-Castillo, Gerardo; Cuevas, Emilio; Terradellas, Enric

    2016-04-01

    One of the most important activities of the Regional Center for Northern Africa, Middle East and Europe of the World Meteorological Organization's Sand and Dust Storm Warning Advisory and Assessment System (WMO SDS-WAS, http://sds-was.aemet.es) is the dust model intercomparison and forecast evaluation, which is deemed an indispensable service to the users and an invaluable tool to assess model skills. Currently, the Regional Center collects daily dust forecasts from models run by nine partners (BSC, ECMWF, NASA, NCEP, SEEVCCC, EMA, CNR-ISAC, NOA and UK Met Office). A multi-model ensemble has also been set up in an effort to provide added-value products to the users. The first problem to address the dust model evaluation is the scarcity of suitable routine observations near the Sahara, the world's largest source of mineral dust. The present contribution presents preliminary results of dust model evaluation using new observational datasets. The current routine evaluation of dust predictions is focused on total-column dust optical depth (DOD) and uses remote-sensing retrievals from sun-photometric (AERONET) and satellite (MODIS) measurements. However, most users of dust forecasts are interested in the concentration near the surface (in the air we breathe) rather than in the total column content. Therefore, evaluation of the predicted surface concentration is also necessary. In this context, the initiative of the African Monsoon Interdisciplinary Analysis (AMMA) International Program to establish permanent measuring stations in the Sahel is extremely important. Tapered Element Oscillating Microbalance (TEOM) monitors continuously record PM10 in M'Bour (Senegal); Cinzana (Mali) and Banizoumbou (Niger). This surface model evaluation is complemented with the PM10 observation from the Air Quality Control and Monitoring Network (AQCMN) of the Canary Islands (Spain). The region, located in the sub-tropical Eastern Atlantic (roughly 100 km west of the Moroccan coast), is

  1. Learning from our apartheid past: human rights challenges for health professionals in contemporary South Africa.

    PubMed

    Baldwin-Ragaven, L; London, L; De Gruchy, J

    2000-01-01

    Central to South Africa's democratic transformation have been attempts to understand how and why human rights abuses were common under apartheid. In testimony to the Truth and Reconciliation Commission evidence has emerged of a wide range of past complicity in human rights abuses by health professionals and their organisations. This has presented a major challenge to the health sector to develop ways to operationalize a commitment to human rights in the future. This paper argues that only after a process of self-reflection, both personal and institutional, which enables a thorough and accurate analysis of why things went so wrong, can the health sector effectively move forward. The authors' perspective draws on the submission to the TRC Health Sector Hearings by the Health and Human Rights Project in 1997, which provides a systemic and case-based analysis of the health sector's role in human rights abuses under apartheid. However, human rights responses have to take account of a changing national and global terrain in which human rights issues are no longer as morally absolute as previously encountered, and in which seemingly insuperable resource constraints, inimical economic policies, and the demobilization of civil society, are serious obstacles. Moreover, the politics of transformation has generated expediencies that threaten to rewrite history in ways that fundamentally cheapen human rights. To address this contradiction, the authors propose a set of objectives that places accountability of health professionals in a human rights framework. These objectives are intended to give substance to the main tasks facing the health sector--to develop and infuse the capacity to recognise and integrate both the 'new' and traditional human rights dilemmas, and to effect personal and institutional transformation. A matrix is presented, linking these objectives to key role players in the health sector and identifying activities specific for each role player. As the health

  2. A review of health and human rights after five years of democracy in South Africa.

    PubMed

    Sarkin, J

    2000-01-01

    South Africa became a democratic state with a supreme Constitution and Bill of Rights in 1994. Between 1994 and 1996 South Africans drafted a new constitution which came into force in 1997. While, the right to health, as well as socio-economic rights is provided for, the health care system in post-apartheid South Africa still mirrors that which existed during the apartheid years. There are still two health care systems. The poorly funded public sector services the majority, while the well-funded private sector services the privileged few. A lack of resources is blamed by the state for its inability to provide better and more widespread health services. This article examines, from a human rights perspective, the successes and challenges in developing the right to health between 1994 to 1999, and provides an overview of the present state of health in South Africa. This article further examines the constitutional provisions on health, and discusses recent constitutional court decisions relevant to the right to health. New and controversial health laws and regulations, affecting health care professionals, medical aid schemes and the availability of pharmaceuticals, are critiqued. The move to devolving health care to the provinces is described. Also discussed are the controversial steps taken by the Department of Health to restructure health structures and services. Progress on key health issues such as HIV/Aids, tobacco, tuberculosis, polio, measles, hepatitis, malaria and abortion are also described. Attention is focused on the role of the Truth and Reconciliation Commission's health hearings in bringing to light violations of human rights in health during apartheid as well as the recommendations made to address these problems.

  3. New Evidences for Preserved Segmentation of the Alpine-Tethyan Domain in the Iberia-Africa Plate Boundary Region

    NASA Astrophysics Data System (ADS)

    Fernandez, M.; Torne, M.; Verges, J.; Buffett, G. G.

    2015-12-01

    Based on gravity analysis and previous integrated studies combining potential fields and seismic data, we demonstrate that the Iberia-Africa plate boundary region is characterized by several tectonically inverted transtensional domains inherited from the Jurassic. Gravity data, when filtered for short wavelengths, show conspicuous positive Bouguer anomalies associated with the Gorringe Bank, the Guadalquivir Bank and the Ronda/Beni-Bousera peridotitic massifs. Gravity modelling combined with seismic and geological data shows that the filtered Bouguer anomalies are compatible with relatively high-density and shallow-buried bodies, which correspond to partly serpentinized peridotitic slices with similar densities and geometries as those proved for the Gorringe Bank. The study indicates that the Alpine convergence between Africa and Iberia since Late Cretaceous times reactivated these transtensional domains, which were less deformed westwards and thus preserved their segmentation. The interpretation of these Bouguer anomalies and their distribution substantiates the double-polarity subduction model proposed for the region, and agrees with the present-day seismically diffuse character of the Iberia-Africa plate boundary.

  4. Human body region enhancement method based on Kinect infrared imaging

    NASA Astrophysics Data System (ADS)

    Yang, Lei; Fan, Yubo; Song, Xiaowei; Cai, Wenjing

    2016-10-01

    To effectively improve the low contrast of human body region in the infrared images, a combing method of several enhancement methods is utilized to enhance the human body region. Firstly, for the infrared images acquired by Kinect, in order to improve the overall contrast of the infrared images, an Optimal Contrast-Tone Mapping (OCTM) method with multi-iterations is applied to balance the contrast of low-luminosity infrared images. Secondly, to enhance the human body region better, a Level Set algorithm is employed to improve the contour edges of human body region. Finally, to further improve the human body region in infrared images, Laplacian Pyramid decomposition is adopted to enhance the contour-improved human body region. Meanwhile, the background area without human body region is processed by bilateral filtering to improve the overall effect. With theoretical analysis and experimental verification, the results show that the proposed method could effectively enhance the human body region of such infrared images.

  5. Implications of Nubian-Like Core Reduction Systems in Southern Africa for the Identification of Early Modern Human Dispersals

    PubMed Central

    Phillips, Natasha

    2015-01-01

    Lithic technologies have been used to trace dispersals of early human populations within and beyond Africa. Convergence in lithic systems has the potential to confound such interpretations, implying connections between unrelated groups. Due to their reductive nature, stone artefacts are unusually prone to this chance appearance of similar forms in unrelated populations. Here we present data from the South African Middle Stone Age sites Uitpanskraal 7 and Mertenhof suggesting that Nubian core reduction systems associated with Late Pleistocene populations in North Africa and potentially with early human migrations out of Africa in MIS 5 also occur in southern Africa during early MIS 3 and with no clear connection to the North African occurrence. The timing and spatial distribution of their appearance in southern and northern Africa implies technological convergence, rather than diffusion or dispersal. While lithic technologies can be a critical guide to human population flux, their utility in tracing early human dispersals at large spatial and temporal scales with stone artefact types remains questionable. PMID:26125972

  6. Implications of Nubian-Like Core Reduction Systems in Southern Africa for the Identification of Early Modern Human Dispersals.

    PubMed

    Will, Manuel; Mackay, Alex; Phillips, Natasha

    2015-01-01

    Lithic technologies have been used to trace dispersals of early human populations within and beyond Africa. Convergence in lithic systems has the potential to confound such interpretations, implying connections between unrelated groups. Due to their reductive nature, stone artefacts are unusually prone to this chance appearance of similar forms in unrelated populations. Here we present data from the South African Middle Stone Age sites Uitpanskraal 7 and Mertenhof suggesting that Nubian core reduction systems associated with Late Pleistocene populations in North Africa and potentially with early human migrations out of Africa in MIS 5 also occur in southern Africa during early MIS 3 and with no clear connection to the North African occurrence. The timing and spatial distribution of their appearance in southern and northern Africa implies technological convergence, rather than diffusion or dispersal. While lithic technologies can be a critical guide to human population flux, their utility in tracing early human dispersals at large spatial and temporal scales with stone artefact types remains questionable.

  7. Ethics review of health research on human participants in South Africa.

    PubMed

    van Wyk, Christa

    2010-06-01

    In terms of South African legislation, all health research on human participants must be submitted to an accredited research ethics committee for independent ethics review. Health research covers a broad spectrum of research, including clinical trials. This article sets out the ethical-legal framework for the functioning and composition of such committees. It also deals with the newly created National Health Research Ethics Council, which registers and audits health research ethics committees. Special attention is given to the conduct of clinical trials. In conclusion, it is submitted that the National Health Act, the Draft Regulations Relating to Research on Human Subjects, and two sets of ethical guidelines adopted by the Department of Health provide a much needed and coherent ethical-legal framework for research in South Africa.

  8. Pathogen-Host Associations and Predicted Range Shifts of Human Monkeypox in Response to Climate Change in Central Africa

    PubMed Central

    Thomassen, Henri A.; Fuller, Trevon; Asefi-Najafabady, Salvi; Shiplacoff, Julia A. G.; Mulembakani, Prime M.; Blumberg, Seth; Johnston, Sara C.; Kisalu, Neville K.; Kinkela, Timothée L.; Fair, Joseph N.; Wolfe, Nathan D.; Shongo, Robert L.; LeBreton, Matthew; Meyer, Hermann; Wright, Linda L.; Muyembe, Jean-Jacques; Buermann, Wolfgang; Okitolonda, Emile; Hensley, Lisa E.; Lloyd-Smith, James O.; Smith, Thomas B.; Rimoin, Anne W.

    2013-01-01

    Climate change is predicted to result in changes in the geographic ranges and local prevalence of infectious diseases, either through direct effects on the pathogen, or indirectly through range shifts in vector and reservoir species. To better understand the occurrence of monkeypox virus (MPXV), an emerging Orthopoxvirus in humans, under contemporary and future climate conditions, we used ecological niche modeling techniques in conjunction with climate and remote-sensing variables. We first created spatially explicit probability distributions of its candidate reservoir species in Africa's Congo Basin. Reservoir species distributions were subsequently used to model current and projected future distributions of human monkeypox (MPX). Results indicate that forest clearing and climate are significant driving factors of the transmission of MPX from wildlife to humans under current climate conditions. Models under contemporary climate conditions performed well, as indicated by high values for the area under the receiver operator curve (AUC), and tests on spatially randomly and non-randomly omitted test data. Future projections were made on IPCC 4th Assessment climate change scenarios for 2050 and 2080, ranging from more conservative to more aggressive, and representing the potential variation within which range shifts can be expected to occur. Future projections showed range shifts into regions where MPX has not been recorded previously. Increased suitability for MPX was predicted in eastern Democratic Republic of Congo. Models developed here are useful for identifying areas where environmental conditions may become more suitable for human MPX; targeting candidate reservoir species for future screening efforts; and prioritizing regions for future MPX surveillance efforts. PMID:23935820

  9. Analysis of adequacy levels for human resources improvement within primary health care framework in Africa

    PubMed Central

    Parent, Florence; Fromageot, Audrey; Coppieters, Yves; Lejeune, Colette; Lemenu, Dominique; Garant, Michèle; Piette, Danielle; Levêque, Alain; De Ketele, Jean-Marie

    2005-01-01

    Human resources in health care system in sub-Saharan Africa are generally picturing a lack of adequacy between expected skills from the professionals and health care needs expressed by the populations. It is, however, possible to analyse these various lacks of adequacy related to human resource management and their determinants to enhance the effectiveness of the health care system. From two projects focused on nurse professionals within the health care system in Central Africa, we present an analytic grid for adequacy levels looking into the following aspects: - adequacy between skills-based profiles for health system professionals, quality of care and service delivery (health care system /medical standards), needs and expectations from the populations, - adequacy between allocation of health system professionals, quality of care and services delivered (health care system /medical standards), needs and expectations from the populations, - adequacy between human resource management within health care system and medical standards, - adequacy between human resource management within education/teaching/training and needs from health care system and education sectors, - adequacy between basic and on-going education and realities of tasks expected and implemented by different categories of professionals within the health care system body, - adequacy between intentions for initial and on-going trainings and teaching programs in health sciences for trainers (teachers/supervisors/health care system professionals/ directors (teaching managers) of schools...). This tool is necessary for decision-makers as well as for health care system professionals who share common objectives for changes at each level of intervention within the health system. Setting this adequacy implies interdisciplinary and participative approaches for concerned actors in order to provide an overall vision of a more broaden system than health district, small island with self-rationality, and in which

  10. The Great Karoo region of South Africa: A carbon source or sink?

    NASA Astrophysics Data System (ADS)

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

    2014-05-01

    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 that began approximately 200 years ago when European farmers first settled the area. In response to changing land use, coupled with shifting rainfall patterns, parts of the landscape are now characterised by badlands on footslopes of valley-sides and complex gully systems on valley floors. Limited precipitation and agricultural intensification, particularly from around the 1920s onwards, resulted in a growing demand for water, and led to the construction of many small reservoirs, most of which are now in-filled with sediment. Whilst the deposited material has provided a means of linking catchment-scale responses to land use changes over the last ca. 100 years, the influence of land degradation on erosion and deposition of soil-associated carbon (C) has received only limited attention. Despite a reversion to extensive agriculture and reduced livestock densities in certain areas, limited vegetation regrowth suggests that soil rehabilitation will be a long-term process. This communication presents preliminary results 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. Sediment deposits from a silted-up reservoir in a small dry valley system was analysed for varying physicochemical parameters. Total Carbon (TC) content was recorded and the sharp decrease in total C content with decreasing depth suggests that land degradation during and after post-European settlement probably led to accelerated erosion of the relatively fertile surface soils, and this presumably resulted in the rapid in-filling of reservoirs with carbon-rich surface material. Overall, the results indicate a sharp decline in soil organic matter (SOM) of eroded material, presumably as a consequence of land degradation. This suggests that in landscapes such as the

  11. Explaining the Ordinary Magic of Stable African Multilingualism in the Vaal Triangle Region in South Africa

    ERIC Educational Resources Information Center

    Coetzee-Van Rooy, Susan

    2014-01-01

    The academic and public debates about language maintenance and language shift in the post-1994 South Africa distract attention from the more productive and important endeavour of explaining the nature of the multilingualism observed among users of African languages in urban contexts. An explanation for this phenomenon is offered here, based on…

  12. Psychology and modern life challenges: the 2nd Middle East and North Africa Regional Conference of Psychology, Amman, Jordan, 2007.

    PubMed

    Knowles, Michael; Sabourin, Michel

    2008-04-01

    The Second Middle East and North Africa Regional Conference of Psychology was held in Amman from 27 April - 1 May 2007 under the Royal Patronage of Her Majesty Queen Rania Al-Abdullah and the auspices of the International Union of Psychological Science, the International Association of Applied Psychology, and the International Association of Cross-Cultural Psychology. It was hosted by the Jordanian Psychological Association whose President was Dr. Asaad Zuby. The President of the Conference and the Local Organizing Committee was Dr. Adnan Farah, the Chair of the Scientific Program Committee was Dr. Mohammad Rimawi, and the Chair of the Regional Advisory Committee was Dr. Marwan Dwairy. The Conference succeeded in attracting participants from 28 countries, including 15 from the Middle East and North Africa region. The Scientific Program explored ways and means to promote the role of psychology in meeting life challenges at regional and international levels. The Conference concluded with the signing of a formal Declaration which called upon governments, academic and professional institutions and organizations, non-governmental organization and other civil society groups, and the United Nations, to work together and to make every possible effort individually and collectively to achieve these goals.

  13. Science and ethics of human immunodeficiency virus/acquired immunodeficiency syndrome controversies in Africa.

    PubMed

    Brewster, David

    2011-09-01

    The human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) epidemic in Africa has raised important ethical issues for both researchers and clinicians. The most notorious controversy has been related to the zidovudine (AZT) trials in Africa in the late 1990s, in which the control groups were given a placebo rather than an effective drug to prevent vertical transmission. This raised concerns in the sponsoring country about exploitation of subjects, injustice and an ethical double standard between donor countries and resource-poor settings. However, the real double standard is between clinical practice standards in Western versus African countries, which must be addressed as part of the increasing global inequity of wealth both between countries and also within countries. There are important limitations to ethical declarations, principles and guidelines on their own without contextual ethical reasoning. The focus on research ethics with the HIV epidemic has led to a relative neglect of ethical issues in clinical practice. Although the scientific advances in HIV/AIDS have changed the ethical issues since the 1990s, there has also been progress in the bioethics of HIV/AIDS in terms of ethical review capability by local committees as well as in exposure to ethical issues by clinicians and researchers in Africa. However, serious concerns remain about the overregulation of research by bureaucratic agencies which could discourage African research on specifically African health issues. There is also a need for African academic institutions and researchers to progressively improve their research capacity with the assistance of research funders and donor agencies.

  14. Late Stone Age human remains from Ishango (Democratic Republic of Congo): New insights on Late Pleistocene modern human diversity in Africa.

    PubMed

    Crevecoeur, I; Brooks, A; Ribot, I; Cornelissen, E; Semal, P

    2016-07-01

    Although questions of modern human origins and dispersal are subject to intense research within and outside Africa, the processes of modern human diversification during the Late Pleistocene are most often discussed within the context of recent human genetic data. This situation is due largely to the dearth of human fossil remains dating to the final Pleistocene in Africa and their almost total absence from West and Central Africa, thus limiting our perception of modern human diversification within Africa before the Holocene. Here, we present a morphometric comparative analysis of the earliest Late Pleistocene modern human remains from the Central African site of Ishango in the Democratic Republic of Congo. The early Late Stone Age layer (eLSA) of this site, dated to the Last Glacial Maximum (25-20 Ky), contains more than one hundred fragmentary human remains. The exceptional associated archaeological context suggests these remains derived from a community of hunter-fisher-gatherers exhibiting complex social and cognitive behaviors including substantial reliance on aquatic resources, development of fishing technology, possible mathematical notations and repetitive use of space, likely on a seasonal basis. Comparisons with large samples of Late Pleistocene and early Holocene modern human fossils from Africa and Eurasia show that the Ishango human remains exhibit distinctive characteristics and a higher phenotypic diversity in contrast to recent African populations. In many aspects, as is true for the inner ear conformation, these eLSA human remains have more affinities with Middle to early Late Pleistocene fossils worldwide than with extant local African populations. In addition, cross-sectional geometric properties of the long bones are consistent with archaeological evidence suggesting reduced terrestrial mobility resulting from greater investment in and use of aquatic resources. Our results on the Ishango human remains provide insights into past African modern

  15. 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

  16. Disentangling the relative effects of bushmeat availability on human nutrition in central Africa

    PubMed Central

    Fa, John E.; Olivero, Jesús; Real, Raimundo; Farfán, Miguel A.; Márquez, Ana L.; Vargas, J. Mario; Ziegler, Stefan; Wegmann, Martin; Brown, David; Margetts, Barrie; Nasi, Robert

    2015-01-01

    We studied links between human malnutrition and wild meat availability within the Rainforest Biotic Zone in central Africa. We distinguished two distinct hunted mammalian diversity distributions, one in the rainforest areas (Deep Rainforest Diversity, DRD) containing taxa of lower hunting sustainability, the other in the northern rainforest-savanna mosaic, with species of greater hunting potential (Marginal Rainforest Diversity, MRD). Wild meat availability, assessed by standing crop mammalian biomass, was greater in MRD than in DRD areas. Predicted bushmeat extraction was also higher in MRD areas. Despite this, stunting of children, a measure of human malnutrition, was greater in MRD areas. Structural equation modeling identified that, in MRD areas, mammal diversity fell away from urban areas, but proximity to these positively influenced higher stunting incidence. In DRD areas, remoteness and distance from dense human settlements and infrastructures explained lower stunting levels. Moreover, stunting was higher away from protected areas. Our results suggest that in MRD areas, forest wildlife rational use for better human nutrition is possible. By contrast, the relatively low human populations in DRD areas currently offer abundant opportunities for the continued protection of more vulnerable mammals and allow dietary needs of local populations to be met. PMID:25639588

  17. Disentangling the relative effects of bushmeat availability on human nutrition in central Africa

    NASA Astrophysics Data System (ADS)

    Fa, John E.; Olivero, Jesús; Real, Raimundo; Farfán, Miguel A.; Márquez, Ana L.; Vargas, J. Mario; Ziegler, Stefan; Wegmann, Martin; Brown, David; Margetts, Barrie; Nasi, Robert

    2015-02-01

    We studied links between human malnutrition and wild meat availability within the Rainforest Biotic Zone in central Africa. We distinguished two distinct hunted mammalian diversity distributions, one in the rainforest areas (Deep Rainforest Diversity, DRD) containing taxa of lower hunting sustainability, the other in the northern rainforest-savanna mosaic, with species of greater hunting potential (Marginal Rainforest Diversity, MRD). Wild meat availability, assessed by standing crop mammalian biomass, was greater in MRD than in DRD areas. Predicted bushmeat extraction was also higher in MRD areas. Despite this, stunting of children, a measure of human malnutrition, was greater in MRD areas. Structural equation modeling identified that, in MRD areas, mammal diversity fell away from urban areas, but proximity to these positively influenced higher stunting incidence. In DRD areas, remoteness and distance from dense human settlements and infrastructures explained lower stunting levels. Moreover, stunting was higher away from protected areas. Our results suggest that in MRD areas, forest wildlife rational use for better human nutrition is possible. By contrast, the relatively low human populations in DRD areas currently offer abundant opportunities for the continued protection of more vulnerable mammals and allow dietary needs of local populations to be met.

  18. Fine-Scale Human Population Structure in Southern Africa Reflects Ecogeographic Boundaries.

    PubMed

    Uren, Caitlin; Kim, Minju; Martin, Alicia R; Bobo, Dean; Gignoux, Christopher R; van Helden, Paul D; Möller, Marlo; Hoal, Eileen G; Henn, Brenna M

    2016-09-01

    Recent genetic studies have established that the KhoeSan populations of southern Africa are distinct from all other African populations and have remained largely isolated during human prehistory until ∼2000 years ago. Dozens of different KhoeSan groups exist, belonging to three different language families, but very little is known about their population history. We examine new genome-wide polymorphism data and whole mitochondrial genomes for >100 South Africans from the ≠Khomani San and Nama populations of the Northern Cape, analyzed in conjunction with 19 additional southern African populations. Our analyses reveal fine-scale population structure in and around the Kalahari Desert. Surprisingly, this structure does not always correspond to linguistic or subsistence categories as previously suggested, but rather reflects the role of geographic barriers and the ecology of the greater Kalahari Basin. Regardless of subsistence strategy, the indigenous Khoe-speaking Nama pastoralists and the N|u-speaking ≠Khomani (formerly hunter-gatherers) share ancestry with other Khoe-speaking forager populations that form a rim around the Kalahari Desert. We reconstruct earlier migration patterns and estimate that the southern Kalahari populations were among the last to experience gene flow from Bantu speakers, ∼14 generations ago. We conclude that local adoption of pastoralism, at least by the Nama, appears to have been primarily a cultural process with limited genetic impact from eastern Africa.

  19. Achieving effective cervical screening coverage in South Africa through human resources and health systems development.

    PubMed

    Kawonga, Mary; Fonn, Sharon

    2008-11-01

    South Africa's cervical screening policy recommends three free Pap smears at ten-year intervals for all women over 30 years of age, aiming to achieve 70% coverage by 2010 by targeting the age group most at risk of developing pre-cancerous cervical lesions. Attaining wide coverage requires an adequate supply of motivated and supported public sector health workers with appropriate training and skills, working in a functional health system. Given the dearth of doctors in South Africa, professional nurses were tasked with performing the bulk of Pap smears at primary care level. Coverage remains sub-optimal and a significant proportion of women with precursor lesions do not receive treatment. Further, health system strengthening - essential for cytology-based screening - has not happened. Research to evaluate alternative screening technologies has proliferated in recent years, but regrettably, strengthening of the health system required to make the new technology work has not received similar attention. Using the South African experience, this article argues that technological interventions and innovations alone are not sufficient to improve cervical screening programmes. Task-shifting is limited unless other human resource concerns (e.g. training, increasing demands on personnel, attrition, and skills mix) are concurrently addressed within a comprehensive workforce development strategy, alongside work to make the health care delivery system functional.

  20. Intracontinental spread of human invasive Salmonella Typhimurium pathovariants in sub-Saharan Africa.

    PubMed

    Okoro, Chinyere K; Kingsley, Robert A; Connor, Thomas R; Harris, Simon R; Parry, Christopher M; Al-Mashhadani, Manar N; Kariuki, Samuel; Msefula, Chisomo L; Gordon, Melita A; de Pinna, Elizabeth; Wain, John; Heyderman, Robert S; Obaro, Stephen; Alonso, Pedro L; Mandomando, Inacio; MacLennan, Calman A; Tapia, Milagritos D; Levine, Myron M; Tennant, Sharon M; Parkhill, Julian; Dougan, Gordon

    2012-11-01

    A highly invasive form of non-typhoidal Salmonella (iNTS) disease has recently been documented in many countries in sub-Saharan Africa. The most common Salmonella enterica serovar causing this disease is Typhimurium (Salmonella Typhimurium). We applied whole-genome sequence-based phylogenetic methods to define the population structure of sub-Saharan African invasive Salmonella Typhimurium isolates and compared these to global Salmonella Typhimurium populations. Notably, the vast majority of sub-Saharan invasive Salmonella Typhimurium isolates fell within two closely related, highly clustered phylogenetic lineages that we estimate emerged independently ∼52 and ∼35 years ago in close temporal association with the current HIV pandemic. Clonal replacement of isolates from lineage I by those from lineage II was potentially influenced by the use of chloramphenicol for the treatment of iNTS disease. Our analysis suggests that iNTS disease is in part an epidemic in sub-Saharan Africa caused by highly related Salmonella Typhimurium lineages that may have occupied new niches associated with a compromised human population and antibiotic treatment.

  1. Human mandibular incisors from the late Middle Pleistocene locality of Hoedjiespunt 1, South Africa.

    PubMed

    Stynder, D D; Moggi-Cecchi, J; Berger, L R; Parkington, J E

    2001-11-01

    The Hoedjiespunt 1 locality is an archaeological and palaeontological site located on the Hoedjiespunt Peninsula at Saldanha Bay, South Africa. In 1996 two human teeth, a left central mandibular incisor and a left lateral mandibular incisor, were discovered during excavations in the late Middle Pleistocene palaeontological layers. These teeth are described and are found to belong to a single subadult individual. Despite their developmental stage, these incisors already display early signs of wear. Their crown diameters are larger than modern and archaeological African comparative material and are most closely comparable with crown diameters of an early Middle Pleistocene and late Middle Pleistocene dental sample from Africa, Europe and Asia. In the light of this metrical evidence, data on two previously excavated maxillary molars, most probably belonging to the same individual, were re-examined. It was found that the Hoedjiespunt 1 hominid possessed dental metrical features (large anterior teeth and small molars) comparable with other African and European hominids referred to the Middle Pleistocene.

  2. Evidence that the Human Pathogenic Fungus Cryptococcus neoformans var. grubii May Have Evolved in Africa

    PubMed Central

    Litvintseva, Anastasia P.; Carbone, Ignazio; Rossouw, Jenny; Thakur, Rameshwari; Govender, Nelesh P.; Mitchell, Thomas G.

    2011-01-01

    Most of the species of fungi that cause disease in mammals, including Cryptococcus neoformans var. grubii (serotype A), are exogenous and non-contagious. Cryptococcus neoformans var. grubii is associated worldwide with avian and arboreal habitats. This airborne, opportunistic pathogen is profoundly neurotropic and the leading cause of fungal meningitis. Patients with HIV/AIDS have been ravaged by cryptococcosis – an estimated one million new cases occur each year, and mortality approaches 50%. Using phylogenetic and population genetic analyses, we present evidence that C. neoformans var. grubii may have evolved from a diverse population in southern Africa. Our ecological studies support the hypothesis that a few of these strains acquired a new environmental reservoir, the excreta of feral pigeons (Columba livia), and were globally dispersed by the migration of birds and humans. This investigation also discovered a novel arboreal reservoir for highly diverse strains of C. neoformans var. grubii that are restricted to southern Africa, the mopane tree (Colophospermum mopane). This finding may have significant public health implications because these primal strains have optimal potential for evolution and because mopane trees contribute to the local economy as a source of timber, folkloric remedies and the edible mopane worm. PMID:21589919

  3. Molecular Epidemiology of Human Rhinoviruses and Enteroviruses Highlights Their Diversity in Sub-Saharan Africa.

    PubMed

    L'Huillier, Arnaud G; Kaiser, Laurent; Petty, Tom J; Kilowoko, Mary; Kyungu, Esther; Hongoa, Philipina; Vieille, Gaël; Turin, Lara; Genton, Blaise; D'Acremont, Valérie; Tapparel, Caroline

    2015-12-08

    Human rhinoviruses (HRVs) and enteroviruses (HEVs) belong to the Enterovirus genus and are the most frequent cause of infection worldwide, but data on their molecular epidemiology in Africa are scarce. To understand HRV and HEV molecular epidemiology in this setting, we enrolled febrile pediatric patients participating in a large prospective cohort assessing the causes of fever in Tanzanian children. Naso/oropharyngeal swabs were systematically collected and tested by real-time RT-PCR for HRV and HEV. Viruses from positive samples were sequenced and phylogenetic analyses were then applied to highlight the HRV and HEV types as well as recombinant or divergent strains. Thirty-eight percent (378/1005) of the enrolled children harboured an HRV or HEV infection. Although some types were predominant, many distinct types were co-circulating, including a vaccinal poliovirus, HEV-A71 and HEV-D68. Three HRV-A recombinants were identified: HRV-A36/HRV-A67, HRV-A12/HRV-A67 and HRV-A96/HRV-A61. Four divergent HRV strains were also identified: one HRV-B strain and three HRV-C strains. This is the first prospective study focused on HRV and HEV molecular epidemiology in sub-Saharan Africa. This systematic and thorough large screening with careful clinical data management confirms the wide genomic diversity of these viruses, brings new insights about their evolution and provides data about associated symptoms.

  4. The financial cost of doctors emigrating from sub-Saharan Africa: human capital analysis

    PubMed Central

    Kanters, Steve; Hagopian, Amy; Bansback, Nick; Nachega, Jean; Alberton, Mark; Au-Yeung, Christopher G; Mtambo, Andy; Bourgeault, Ivy L; Luboga, Samuel; Hogg, Robert S; Ford, Nathan

    2011-01-01

    Objective To estimate the lost investment of domestically educated doctors migrating from sub-Saharan African countries to Australia, Canada, the United Kingdom, and the United States. Design Human capital cost analysis using publicly accessible data. Settings Sub-Saharan African countries. Participants Nine sub-Saharan African countries with an HIV prevalence of 5% or greater or with more than one million people with HIV/AIDS and with at least one medical school (Ethiopia, Kenya, Malawi, Nigeria, South Africa, Tanzania, Uganda, Zambia, and Zimbabwe), and data available on the number of doctors practising in destination countries. Main outcome measures The financial cost of educating a doctor (through primary, secondary, and medical school), assuming that migration occurred after graduation, using current country specific interest rates for savings converted to US dollars; cost according to the number of source country doctors currently working in the destination countries; and savings to destination countries of receiving trained doctors. Results In the nine source countries the estimated government subsidised cost of a doctor’s education ranged from $21 000 (£13 000; €15 000) in Uganda to $58 700 in South Africa. The overall estimated loss of returns from investment for all doctors currently working in the destination countries was $2.17bn (95% confidence interval 2.13bn to 2.21bn), with costs for each country ranging from $2.16m (1.55m to 2.78m) for Malawi to $1.41bn (1.38bn to 1.44bn) for South Africa. The ratio of the estimated compounded lost investment over gross domestic product showed that Zimbabwe and South Africa had the largest losses. The benefit to destination countries of recruiting trained doctors was largest for the United Kingdom ($2.7bn) and United States ($846m). Conclusions Among sub-Saharan African countries most affected by HIV/AIDS, lost investment from the emigration of doctors is considerable. Destination countries should

  5. Tracing the route of modern humans out of Africa by using 225 human genome sequences from Ethiopians and Egyptians.

    PubMed

    Pagani, Luca; Schiffels, Stephan; Gurdasani, Deepti; Danecek, Petr; Scally, Aylwyn; Chen, Yuan; Xue, Yali; Haber, Marc; Ekong, Rosemary; Oljira, Tamiru; Mekonnen, Ephrem; Luiselli, Donata; Bradman, Neil; Bekele, Endashaw; Zalloua, Pierre; Durbin, Richard; Kivisild, Toomas; Tyler-Smith, Chris

    2015-06-04

    The predominantly African origin of all modern human populations is well established, but the route taken out of Africa is still unclear. Two alternative routes, via Egypt and Sinai or across the Bab el Mandeb strait into Arabia, have traditionally been proposed as feasible gateways in light of geographic, paleoclimatic, archaeological, and genetic evidence. Distinguishing among these alternatives has been difficult. We generated 225 whole-genome sequences (225 at 8× depth, of which 8 were increased to 30×; Illumina HiSeq 2000) from six modern Northeast African populations (100 Egyptians and five Ethiopian populations each represented by 25 individuals). West Eurasian components were masked out, and the remaining African haplotypes were compared with a panel of sub-Saharan African and non-African genomes. We showed that masked Northeast African haplotypes overall were more similar to non-African haplotypes and more frequently present outside Africa than were any sets of haplotypes derived from a West African population. Furthermore, the masked Egyptian haplotypes showed these properties more markedly than the masked Ethiopian haplotypes, pointing to Egypt as the more likely gateway in the exodus to the rest of the world. Using five Ethiopian and three Egyptian high-coverage masked genomes and the multiple sequentially Markovian coalescent (MSMC) approach, we estimated the genetic split times of Egyptians and Ethiopians from non-African populations at 55,000 and 65,000 years ago, respectively, whereas that of West Africans was estimated to be 75,000 years ago. Both the haplotype and MSMC analyses thus suggest a predominant northern route out of Africa via Egypt.

  6. Tracing the Route of Modern Humans out of Africa by Using 225 Human Genome Sequences from Ethiopians and Egyptians

    PubMed Central

    Pagani, Luca; Schiffels, Stephan; Gurdasani, Deepti; Danecek, Petr; Scally, Aylwyn; Chen, Yuan; Xue, Yali; Haber, Marc; Ekong, Rosemary; Oljira, Tamiru; Mekonnen, Ephrem; Luiselli, Donata; Bradman, Neil; Bekele, Endashaw; Zalloua, Pierre; Durbin, Richard; Kivisild, Toomas; Tyler-Smith, Chris

    2015-01-01

    The predominantly African origin of all modern human populations is well established, but the route taken out of Africa is still unclear. Two alternative routes, via Egypt and Sinai or across the Bab el Mandeb strait into Arabia, have traditionally been proposed as feasible gateways in light of geographic, paleoclimatic, archaeological, and genetic evidence. Distinguishing among these alternatives has been difficult. We generated 225 whole-genome sequences (225 at 8× depth, of which 8 were increased to 30×; Illumina HiSeq 2000) from six modern Northeast African populations (100 Egyptians and five Ethiopian populations each represented by 25 individuals). West Eurasian components were masked out, and the remaining African haplotypes were compared with a panel of sub-Saharan African and non-African genomes. We showed that masked Northeast African haplotypes overall were more similar to non-African haplotypes and more frequently present outside Africa than were any sets of haplotypes derived from a West African population. Furthermore, the masked Egyptian haplotypes showed these properties more markedly than the masked Ethiopian haplotypes, pointing to Egypt as the more likely gateway in the exodus to the rest of the world. Using five Ethiopian and three Egyptian high-coverage masked genomes and the multiple sequentially Markovian coalescent (MSMC) approach, we estimated the genetic split times of Egyptians and Ethiopians from non-African populations at 55,000 and 65,000 years ago, respectively, whereas that of West Africans was estimated to be 75,000 years ago. Both the haplotype and MSMC analyses thus suggest a predominant northern route out of Africa via Egypt. PMID:26027499

  7. 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

  8. Field Epidemiology and Laboratory Training Programs in West Africa as a model for sustainable partnerships in animal and human health.

    PubMed

    Becker, Karen M; Ohuabunwo, Chima; Ndjakani, Yassa; Nguku, Patrick; Nsubuga, Peter; Mukanga, David; Wurapa, Frederick

    2012-09-01

    The concept of animal and human health experts working together toward a healthier world has been endorsed, but challenges remain in identifying concrete actions to move this one health concept from vision to action. In 2008, as a result of avian influenza outbreaks in West Africa, international donor support led to a unique opportunity to invest in Field Epidemiology and Laboratory Training Programs (FELTPs) in the region that engaged the animal and human health sectors to strengthen the capacity for prevention and control of zoonotic diseases. The FELTPs mixed 25% to 35% classroom and 65% to 75% field-based training and service for cohorts of physicians, veterinarians, and laboratory scientists. They typically consisted of a 2-year course leading to a master's degree in field epidemiology and public health laboratory management for midlevel public health leaders and competency-based short courses for frontline public health surveillance workers. Trainees and graduates work in multidisciplinary teams to conduct surveillance, outbreak investigations, and epidemiological studies for disease control locally and across borders. Critical outcomes of these programs include development of a cadre of public health leaders with core skills in integrated disease surveillance, outbreak investigation, vaccination campaigns, laboratory diagnostic testing, and epidemiological studies that address priority public health problems. A key challenge exists in identifying ways to successfully scale up and transform this innovative donor-driven program into a sustainable multisectoral one health workforce capacity development model.

  9. Organochlorine pesticide levels in Clarias gariepinus from polluted freshwater impoundments in South Africa and associated human health risks.

    PubMed

    Barnhoorn, I E J; van Dyk, J C; Genthe, B; Harding, W R; Wagenaar, G M; Bornman, M S

    2015-02-01

    There are increasing concerns regarding the safe human consumption of fish from polluted, freshwater impoundments. The aim of this study was to analyse the muscle tissue of the sharptooth catfish Clarias gariepinus for selected organo-chlorine pesticides (OCPs) and to perform a human health risk assessment using a standard protocol described by the United States Environmental Protection Agency (US EPA). Fish were collected from the polluted Roodeplaat-(RDPD), Rietvlei-(RVD) and Hartbeespoort (HBPD) Dam impoundments located in the north-eastern regions of South Africa. GC-MS analyses showed levels of various OCPs in fish muscle samples from all three impoundments. For fish collected from the RDPD, p,p'-DDE, endosulfan, lindane and β- and δ-HCH were the most prevalent OCPs detected, while p,p'-DDE and endosulfan were the most predominant in fish from the RVD. Lindane and β- and δ-HCH were the main OCPs detected in fish from the HBPD. Dieldrin was the only OCP detected at concentrations for which a cancer risk and a hazard index above the acceptable risk levels were estimated. This was the case for fish from both the RDPD and RVD impoundments. No toxic risk was estimated should fish from the HBPD be consumed.

  10. Resequencing data provide no evidence for a human bottleneck in Africa during the penultimate glacial period.

    PubMed

    Sjödin, Per; E Sjöstrand, Agnès; Jakobsson, Mattias; Blum, Michael G B

    2012-07-01

    Based on the accumulation of genetic, climatic, and fossil evidence, a central theory in paleoanthropology stipulates that a demographic bottleneck coincided with the origin of our species Homo Sapiens. This theory proposes that anatomically modern humans--which were only present in Africa at the time--experienced a drastic bottleneck during the penultimate glacial age (130-190 kya) when a cold and dry climate prevailed. Two scenarios have been proposed to describe the bottleneck, which involve either a fragmentation of the range occupied by humans or the survival of one small group of humans. Here, we analyze DNA sequence data from 61 nuclear loci sequenced in three African populations using Approximate Bayesian Computation and numerical simulations. In contrast to the bottleneck theory, we show that a simple model without any bottleneck during the penultimate ice age has the greatest statistical support compared with bottleneck models. Although the proposed bottleneck is ancient, occurring at least 130 kya, we can discard the possibility that it did not leave detectable footprints in the DNA sequence data except if the bottleneck involves a less than a 3-fold reduction in population size. Finally, we confirm that a simple model without a bottleneck is able to reproduce the main features of the observed patterns of genetic variation. We conclude that models of Pleistocene refugium for modern human origins now require substantial revision.

  11. Human rotavirus vaccine (Rotarix): focus on effectiveness and impact 6 years after first introduction in Africa.

    PubMed

    O'Ryan, Miguel; Giaquinto, Carlo; Benninghoff, Bernd

    2015-01-01

    A decade after licensure of the human rotavirus vaccine (HRV), a wealth of evidence supports a reduction of rotavirus (RV) gastroenteritis-associated mortality and hospitalizations following HRV inclusion in national immunization programs. Nevertheless, the majority of real-world data has been generated in high- or middle-income settings. Clinical efficacy trials previously indicated RV vaccine performance may be lower in less-developed countries compared with wealthier counterparts. Using recently published data from Africa, we examine the effectiveness and impact of HRV in resource-deprived areas, exploring whether vaccine performance differs by socioeconomic setting and the potential underlying factors. HRV vaccine effectiveness in early adopting African countries has proven to be similar or even superior to the efficacy results observed in pre-licensure studies.

  12. Signatures of Adaptation in Human Invasive Salmonella Typhimurium ST313 Populations from Sub-Saharan Africa

    PubMed Central

    Okoro, Chinyere K.; Barquist, Lars; Connor, Thomas R.; Harris, Simon R.; Clare, Simon; Stevens, Mark P.; Arends, Mark J.; Hale, Christine; Kane, Leanne; Pickard, Derek J.; Hill, Jennifer; Harcourt, Katherine; Parkhill, Julian; Dougan, Gordon; Kingsley, Robert A.

    2015-01-01

    Two lineages of Salmonella enterica serovar Typhimurium (S. Typhimurium) of multi-locus sequence type ST313 have been linked with the emergence of invasive Salmonella disease across sub-Saharan Africa. The expansion of these lineages has a temporal association with the HIV pandemic and antibiotic usage. We analysed the whole genome sequence of 129 ST313 isolates representative of the two lineages and found evidence of lineage-specific genome degradation, with some similarities to that observed in S. Typhi. Individual ST313 S. Typhimurium isolates exhibit a distinct metabolic signature and modified enteropathogenesis in both a murine and cattle model of colitis, compared to S. Typhimurium outside of the ST313 lineages. These data define phenotypes that distinguish ST313 isolates from other S. Typhimurium and may represent adaptation to a distinct pathogenesis and lifestyle linked to an-immuno-compromised human population. PMID:25803844

  13. Seasonal availability of edible underground and aboveground carbohydrate resources to human foragers on the Cape south coast, South Africa.

    PubMed

    De Vynck, Jan C; Cowling, Richard M; Potts, Alastair J; Marean, Curtis W

    2016-01-01

    The coastal environments of South Africa's Cape Floristic Region (CFR) provide some of the earliest and most abundant evidence for the emergence of cognitively modern humans. In particular, the south coast of the CFR provided a uniquely diverse resource base for hunter-gatherers, which included marine shellfish, game, and carbohydrate-bearing plants, especially those with Underground Storage Organs (USOs). It has been hypothesized that these resources underpinned the continuity of human occupation in the region since the Middle Pleistocene. Very little research has been conducted on the foraging potential of carbohydrate resources in the CFR. This study focuses on the seasonal availability of plants with edible carbohydrates at six-weekly intervals over a two-year period in four vegetation types on South Africa's Cape south coast. Different plant species were considered available to foragers if the edible carbohydrate was directly (i.e. above-ground edible portions) or indirectly (above-ground indications to below-ground edible portions) visible to an expert botanist familiar with this landscape. A total of 52 edible plant species were recorded across all vegetation types. Of these, 33 species were geophytes with edible USOs and 21 species had aboveground edible carbohydrates. Limestone Fynbos had the richest flora, followed by Strandveld, Renosterveld and lastly, Sand Fynbos. The availability of plant species differed across vegetation types and between survey years. The number of available USO species was highest for a six-month period from winter to early summer (Jul-Dec) across all vegetation types. Months of lowest species' availability were in mid-summer to early autumn (Jan-Apr); the early winter (May-Jun) values were variable, being highest in Limestone Fynbos. However, even during the late summer carbohydrate "crunch," 25 carbohydrate bearing species were visible across the four vegetation types. To establish a robust resource landscape will require

  14. Planning, Plumbing, or Posturing? Explaining the Weakness of Human Resource Development Structures and Policies in South Africa

    ERIC Educational Resources Information Center

    Allais, Stephanie; Marock, Carmel; Ngcwangu, Siphelo

    2017-01-01

    In South Africa, a national peak structure, the Human Resource Development Council, led by the Deputy President and consisting of key Cabinet Ministers, senior leaders from organised labour and business, community representatives, professional bodies and experts from research and higher education, was established to enable high-level coordination…

  15. Human Resources Development and the Skills Crisis in South Africa: The Need for a Multi-Pronged Strategy

    ERIC Educational Resources Information Center

    Kraak, Andre

    2005-01-01

    This article presents a critique of the 'high skills' argument which, in the international literature, presents a high skill strategy as an adjunct and necessary condition for the successful expansion of human resources development (HRD) alongside social market institutions and 'joined up' policy. For a developing country such as South Africa,…

  16. Recruitment and Selection Strategies in Optometric Education towards Addressing Human Resource Disparities in Sub-Saharan Africa

    ERIC Educational Resources Information Center

    Moodley, V. R.; Loughman, James; Naidoo, K. S.

    2015-01-01

    The dire need for eye care services and a dearth of human resources (HR) in sub-Saharan Africa motivated the setting up of new optometry programmes. However, to make a meaningful impact, geographical, gender, economic and educational disparities must additionally be addressed. A qualitative study utilizing purposive sampling to select academic…

  17. The dominant Anopheles vectors of human malaria in Africa, Europe and the Middle East: occurrence data, distribution maps and bionomic précis

    PubMed Central

    2010-01-01

    Background This is the second in a series of three articles documenting the geographical distribution of 41 dominant vector species (DVS) of human malaria. The first paper addressed the DVS of the Americas and the third will consider those of the Asian Pacific Region. Here, the DVS of Africa, Europe and the Middle East are discussed. The continent of Africa experiences the bulk of the global malaria burden due in part to the presence of the An. gambiae complex. Anopheles gambiae is one of four DVS within the An. gambiae complex, the others being An. arabiensis and the coastal An. merus and An. melas. There are a further three, highly anthropophilic DVS in Africa, An. funestus, An. moucheti and An. nili. Conversely, across Europe and the Middle East, malaria transmission is low and frequently absent, despite the presence of six DVS. To help control malaria in Africa and the Middle East, or to identify the risk of its re-emergence in Europe, the contemporary distribution and bionomics of the relevant DVS are needed. Results A contemporary database of occurrence data, compiled from the formal literature and other relevant resources, resulted in the collation of information for seven DVS from 44 countries in Africa containing 4234 geo-referenced, independent sites. In Europe and the Middle East, six DVS were identified from 2784 geo-referenced sites across 49 countries. These occurrence data were combined with expert opinion ranges and a suite of environmental and climatic variables of relevance to anopheline ecology to produce predictive distribution maps using the Boosted Regression Tree (BRT) method. Conclusions The predicted geographic extent for the following DVS (or species/suspected species complex*) is provided for Africa: Anopheles (Cellia) arabiensis, An. (Cel.) funestus*, An. (Cel.) gambiae, An. (Cel.) melas, An. (Cel.) merus, An. (Cel.) moucheti and An. (Cel.) nili*, and in the European and Middle Eastern Region: An. (Anopheles) atroparvus, An. (Ano

  18. Application of the NCAR regional climate model to eastern Africa: 1. Simulation of the short rains of 1988

    NASA Astrophysics Data System (ADS)

    Sun, Liqiang; Semazzi, Fredrick H. M.; Giorgi, Filippo; Ogallo, Laban

    1999-03-01

    The National Center for Atmospheric Research (NCAR) Regional Climate Model (RegCM2) is employed to investigate the physical mechanisms that govern the October-December rains over eastern Africa. The model employs the Mercator conformai projection, with a domain of 5580 km × 5040 km centered at 31°E, 4°S, and a horizontal grid point spacing of 60 km. The simulation period is October-December 1988, and the model initial and lateral boundary conditions are taken from ECMWF reanalysis. A number of month-long simulations have been conducted to optimize various parameterizations of the model which include the following factors: cumulus convection, moisture parameterization, radiative transfer formulation, surface processes, boundary layer physics, and the lateral boundary conditions. The model was successfully customized over eastern Africa. The model simulates the large-scale circulation characteristics over the region as well as local features such as the dominant precipitation maxima, the Turkana low-level jet, and the diurnal reversal in the lake/land breeze circulation over Lake Victoria. Several model deficiencies are also identified. They include a negative rainfall bias over the western portions of the domain and the Kenya Highlands and a temperature bias over the tropical forest regions. Systematic analysis of surface water budget reveals that evapotranspiration is a major sink in the water budget over the regions where precipitation is moderate or small, while the role of runoff and drainage becomes important over the regions where precipitation is abundant. The model simulations also suggest that during the short-rains season, the large-scale circulation anomalies play the most important role in shaping the precipitation anomalies.

  19. Malaria control in the African Region: perceptions and viewspoints on proceedings of the Africa Leaders Malaria Alliance (ALMA)

    PubMed Central

    2011-01-01

    Union and regional economic communities to address the cross-border dimension of malaria control. It was agreed that countries needed to secure adequate domestic and external funding for sustained commitment to malaria elimination; strengthen national malaria control programmes in the context of broader health system strengthening; ensure free access to long-lasting insecticide treated nets and malaria diagnosis and treatment for vulnerable groups; strengthen human resource capacity at central, district and community levels; and establish strong logistics, information and surveillance systems. Conclusion It is critically important for countries to have a clear vision and strategy for malaria elimination; effective leadership of national malaria control programmes; draw lessons from other African countries that have succeeded to dramatically reduce the burden of malaria; and sustain funding and ongoing interventions. PMID:21810213

  20. Co-movement of Africa's equity markets: Regional and global analysis in the frequency-time domains

    NASA Astrophysics Data System (ADS)

    Boako, Gideon; Alagidede, Paul

    2017-02-01

    This paper examines regional and global co-movement of Africa's stock markets using the three-dimensional continuous Morlet wavelet transform methodology. The analyses which are done in segments investigate co-movements with global markets; bilateral exchange rates expressed in US dollars and euro; and four regional markets in Africa. First, we find evidence of stronger co-movements broadly narrowed to short-run fluctuations. The co-movements are time-varying and commonly non-homogeneous - with phase difference arrow vectors implying lead-lag relationships. The presence of lead-lag effects and stronger co-movements at short-run fluctuations may induce arbitrage and diversification opportunities to both local and international investors with long-term investment horizons. The findings also reveal that some African equity markets are, to a degree, segmented from volatilities of the dollar and euro exchange rates. Thus, inferring that, ceteris paribus, international investors may diversify their portfolio investments across those markets without worrying about the effects of currency price volatility.

  1. The Ysterfontein 1 Middle Stone Age site, South Africa, and early human exploitation of coastal resources

    PubMed Central

    Klein, Richard G.; Avery, Graham; Cruz-Uribe, Kathryn; Halkett, David; Parkington, John E.; Steele, Teresa; Volman, Thomas P.; Yates, Royden

    2004-01-01

    Human fossils and the genetics of extant human populations indicate that living people derive primarily from an African population that lived within the last 200,000 years. Yet it was only ≈50,000 years ago that the descendants of this population spread to Eurasia, where they swamped or replaced the Neanderthals and other nonmodern Eurasians. Based on archaeological observations, the most plausible hypothesis for the delay is that Africans and Eurasians were behaviorally similar until 50,000 years ago, and it was only at this time that Africans developed a behavioral advantage. The archaeological findings come primarily from South Africa, where they suggest that the advantage involved much more effective use of coastal resources. Until now, the evidence has come mostly from deeply stratified caves on the south (Indian Ocean) coast. Here, we summarize results from recent excavations at Ysterfontein 1, a deeply stratified shelter in a contrasting environment on the west (Atlantic) coast. The Ysterfontein 1 samples of human food debris must be enlarged for a full comparison to samples from other relevant sites, but they already corroborate two inferences drawn from south coast sites: (i) coastal foragers before 50,000 years ago did not fish routinely, probably for lack of appropriate technology, and (ii) they collected tortoises and shellfish less intensively than later people, probably because their populations were smaller. PMID:15007171

  2. The Role of Education in Building a Future World Based on Democracy and Development: Regional Perspectives from Africa, Latin America, and South Asia.

    ERIC Educational Resources Information Center

    Woolman, David C.

    This paper begins with a comparative regional survey of the current status of democracy and development in Africa, Latin America, and South Asia. Each region shares a legacy of colonial domination by European powers. The comparative study uses criteria from the basic needs approach. Critical social thought and future visions about democracy and…

  3. The history and composition of the Raymond A. Dart Collection of Human Skeletons at the University of the Witwatersrand, Johannesburg, South Africa.

    PubMed

    Dayal, Manisha R; Kegley, Anthony D T; Strkalj, Goran; Bidmos, Mubarak A; Kuykendall, Kevin L

    2009-10-01

    The Raymond A. Dart Collection of Human Skeletons (Dart Collection) is housed in the School of Anatomical Sciences at the University of the Witwatersrand, Johannesburg, South Africa, and comprises one of the largest documented cadaver-derived human skeletal assemblages in the world. This collection originated in the early 1920s as a result of the efforts of Raymond Dart and continues to grow. The skeletons included represent varied indigenous and immigrant populations from southern Africa, Europe and Asia. This contribution documents the history of the collection and provides an updated inventory and demographic assessment of this valuable research collection. According to a recent inventory the Dart Collection currently comprises 2,605 skeletons representing individuals from regional SA African (76%), White (15%), Coloured (4%) and Indian (0.3%) populations. A large proportion of the skeletons (71%) represent males. The recorded ages at death range from the first year to over 100 years of age, but the majority of individuals died between the ages of 20 and 70. The Dart Collection has been affected by collection procedures based on availability. All of the cadavers collected before 1958, and large proportions subsequently, were derived from unclaimed bodies in regional South African hospitals. Some details of documentation (age at death, population group) are estimates and some aspects of the collection demographics (sex ratios) do not closely reflect any living South African population. Our inventory and analysis of the Dart Collection is aimed to assist researchers planning research on the materials from this collection.

  4. Consistent rainy season changes predicted from Regional Climate Models ensembles indicate threats to crop production in West Africa

    NASA Astrophysics Data System (ADS)

    Wisser, D.; Sylla, M. B.; Ibrahim, B.

    2014-12-01

    Agricultural production in West Africa is extremely vulnerable to precipitation change and variability. Designing adaptation options to anticipate these changes in precipitation requires robust predicting future climate conditions. Output from Global Circulation Models (GCMs) is too coarse to be used directly to assess regional and high order statistics changes. We use output from a set of Regional Climate Models that dynamically downscale CMIP5 GCMs and analyze mid-century changes in the characteristics of precipitation in West Africa over cropland areas. For each RCM/GCM combinations, we compared predicted precipitation for the period 2035-2065 under the RCP 8.5 scenario with its historical reconstruction of 1975-2005. The mean changes emerging from an analysis of the ensemble of 15 RCM/GCM combinations suggest moderate (~3%) increases in annual precipitation,a very consistent delay in the onset of the rainy season (1 to 4 days from South to North) and no consistent change in the ending of the rainy season. This illustrates a general shortening of the rainy season. An analysis of dry spells (periods of consecutive days with less than 5 mm) for a durations of between 5 and 15 days revealed an increased probability of experiencing longer dry spells during the rainy season in the future climate, coupled with a general intensification of precipitation. This finding was consistent across all models. Our analysis promotes regional prioritization of adaptation measures to the changes in precipitation characteristics that could potentially have detrimental effects on crop yields while also affecting water resources management, species distribution, and others sectors. Increased storage of water, in combination with supplemental irrigation can be an important mechanism for adapting to the effects for regional precipitation changes on crop yield.

  5. The hydrological cycle of the Niger River basin simulated by the CORDEX-Africa regional climate models

    NASA Astrophysics Data System (ADS)

    Mascaro, G.; White, D. D.; Westerhoff, P.; Bliss, N.

    2015-12-01

    The Niger River Basin (NRB) is a large transnational watershed of ~1.5 million km2, whose water resources sustain more than 100 million people of nine countries in West Africa. Evaluating the reliability of climate simulations in the region is essential to support water sustainability and food security under possible future climatic changes and population growth. Here, we assess the ability of a set of state-of-the-art regional climate models (RCMs) of the COordinated Regional climate Downscaling EXperiment (CORDEX)-Africa to reproduce the hydrologic cycle of the NRB. For this aim, we adopt a verification framework based on the mass conservation principle that assumes that the mean annual difference between precipitation and evaporation equals the long-term mean discharge. We focus on four nested sub-basins encompassing different climatic zones with available discharge observations. We found that most RCMs overestimate the mean annual runoff (from +10% to +400%), because of a positive bias in the simulation of precipitation and a weak hydrologic cycle in the evaporation channel. Some exceptions are found in the more humid sub-basin upstream where a few climate simulations are not able to capture the intensity of the West African monsoon. Analyses of the water balance components also revealed that the signature of the RCMs is more significant than that of the driving General Circulation Model, likely due to the specific schemes adopted in the RCMs to parameterize the land-surface processes. This work is useful to increase the utility of regional climate simulations in impact studies supporting the development of water management polices and
planning of hydraulic infrastructures in the basin.

  6. Ground Truth, Magnitude Calibration and Regional Phase Propagation and Detection in the Middle East and Horn of Africa

    SciTech Connect

    Nyblade, A; Brazier, R; Adams, A; Park, Y; Rodgers, A; Al-Amri, A

    2007-07-08

    In this project, we are exploiting several seismic data sets to improve U.S. operational capabilities to monitor for low yield nuclear tests across the Middle East (including the Iranian Plateau, Zagros Mountains, Arabian Peninsula, Turkish Plateau, Gulf of Aqaba, Dead Sea Rift) and the Horn of Africa (including the northern part of the East African Rift, Afar Depression, southern Red Sea and Gulf of Aden). The data sets are being used to perform three related tasks. (1) We are determining moment tensors, moment magnitudes and source depths for regional events in the magnitude 3.0 to 6.0 range. (2) These events are being used to characterize high-frequency (0.5-16 Hz) regional phase attenuation and detection thresholds, especially from events in Iran recorded at stations across the Arabian Peninsula. (3) We are collecting location ground truth at GT5 (local) and GT20 (regional) levels for seismic events with M > 2.5, including source geometry information and source depths. Towards meeting these objectives, seismograms from earthquakes in the Zagros Mountains recorded at regional distances have been inverted for moment tensors, which have then been used to create synthetic seismograms to determine the source depths of the earthquakes via waveform matching. The source depths have been confirmed by modeling teleseismic depth phases recorded on GSN and IMS stations. Early studies of the distribution of seismicity in the Zagros region found evidence for earthquakes in the upper mantle. But subsequent relocations of teleseismic earthquakes suggest that source depths are generally much shallower, lying mainly within the upper crust. All of the regional events studied so far nucleated within the upper crust, and most of the events have thrust mechanisms. The source mechanisms for these events are being used to characterize high-frequency (0.5-16 Hz) regional phase attenuation and detection thresholds for broadband seismic stations in the Arabian Peninsula, including IMS

  7. Analysis of two Saharan dust events of North Africa in the Mediterranean region by Using SKIRON/Eta model

    NASA Astrophysics Data System (ADS)

    Benaouda, D.; Kallos, G.; Azzi, A.; Louka, P.; Benlefki, A.

    2009-04-01

    aerosol is involved in many important processes in Earth's climate system, with important implications for air quality, climate, atmospheric chemistry, and the biosphere, and different impacts on human health. The relative importance of mineral dust in particulate matter depends on location, season and particle size, mainly concentrated in the coarse fraction. Its impacts on climate and environment have increased years after years and needs to be more understood. In the present work, the relationships between the meteorological conditions and dust transport phenomena from the Saharan regions of north Africa and their transport, deposition in both modes, dry and wet deposition in the Mediterranean region, and the Atlantic Ocean, during two dust events namely: case I (01/03/04 - 06/03/04), case II (29/05/05 - 03/06/05), that have been analysed and their major characteristics have been discussed. This analysis has been performed with the aid of the SKIRON modelling system of the University of Athens. The dust module of SKIRON/Eta model incorporates the state of the art parameterization of all the major phases of the desert dust cycle such as production, diffusion, advection and removal. Model results have been compared with TOMS-AI (Total Ozone Mapping Spectrophotometer Aerosol Index) data for a qualitative comparison of the model. The work has been conducted at the framework of TEMPUS project MADEPODIM.

  8. Did dung beetles arise in Africa? A phylogenetic hypothesis based on five gene regions.

    PubMed

    Sole, Catherine L; Scholtz, Clarke H

    2010-08-01

    Scarabaeinae dung beetle phylogenetics are poorly understood, although recent phylogenetic reconstruction based on morphology and molecular analyses are congruent on the hypothesis that the oldest Gondwana tribes are polyphyletic and that representatives of the ancestral groups are found in Africa. We present a molecular phylogeny of the African representatives of the two oldest tribes, Canthonini (the putative ancestor of all "rollers") and Dichotomiini (thought to represent the ancestral "tunnellers"), based on partial sequence data from two mitochondrial and three nuclear genes, extracted from eight of the nine dichotomiine genera and 17 of the 23 genera of Canthonini. Three well-supported lineages were consistently obtained. Divergence times estimated the origin of the two tribes at around 56 million years ago (MYA) with the splits of the three dung beetle lineages being estimated to have taken place between 40 and 34MYA. The ages of these splits and subsequent radiation of the modern dung beetle groups concur with those predicted by the fossil record and coincide with the proposed age of radiation of the large mammal groups with whose dung most African dung beetles are still associated. Dispersal of dung beetle groups from Africa is proposed as a biogeographic model, and evidence is presented that dung beetles disperse quickly and widely across continents, and even oceans.

  9. Land Cover Mapping for the Development of Green House Gas (GHG) Inventories in the Eastern and Southern Africa Region

    NASA Astrophysics Data System (ADS)

    Wakhayanga, J. A.; Oduor, P.; Korme, T.; Farah, H.; Limaye, A. S.; Irwin, D.; Artis, G.

    2014-12-01

    Anthropogenic activities are responsible for the largest share of green house gas (GHG) emissions. Research has shown that greenhouse gases cause radioactive forcing in the stratosphere, leading to ozone depletion. Different land cover types act as sources or sinks of carbon dioxide (CO2), the most dominant GHG.Under the oversight of the United Nations Framework Convention on Climate Change (UNFCCC) the Eastern and Southern Africa (ESA) region countries are developing Sustainable National GHG Inventory Management Systems. While the countries in the ESA region are making substantial progress in setting up GHG inventories, there remains significant constraints in the development of quality and sustainable National GHG Inventory Systems. For instance, there are fundamental challenges in capacity building and technology transfer, which can affect timely and consistent reporting on the land use, land-use change and forestry (LULUCF) component of the GHG inventory development. SERVIR Eastern and Southern Africa is a partnership project between the National Aeronautics and Space Administration (NASA) and the Regional Center for Mapping of Resources for Development (RCMRD), an intergovernmental organization in Africa, with 21 member states in the ESA region. With support from the United States Agency for International Development (USAID), SERVIR ESA is implementing the GHG Project in 9 countries. The main deliverables of the project are land cover maps for the years 2000 and 2010 (also 1990 for Malawi and Rwanda), and related technical reports, as well as technical training in land cover mapping using replicable methodologies. Landsat imagery which is freely available forms the main component of earth observation input data, in addition to ancillary data collected from each country. Supervised classification using maximum likelihood algorithm is applied to the Landsat images. The work is completed for the initial 6 countries (Malawi, Zambia, Rwanda, Tanzania, Botswana, and

  10. The relationship between African easterly waves and daily rainfall over West Africa: observations and regional climate simulations

    NASA Astrophysics Data System (ADS)

    Crétat, Julien; Vizy, Edward K.; Cook, Kerry H.

    2015-01-01

    The relationship between summer African easterly waves (AEWs) and daily rainfall is assessed in West Africa for 1998-2008 using various reanalyses, satellite-derived rainfall products, and a regional climate model (RCM) run at 90- and 30-km resolutions. 3-5 and 6-9 day AEWs are extracted by filtering daily 700 hPa meridional wind time series at 1°W and 11.5°N, and 1°W and 17.5°N, respectively. Both observed and simulated rainfall anomalies are of larger magnitude over West Africa during 3-5-d than 6-9-d AEWs. The RCM simulates larger rainfall rates in phase with the 3-5-d wave trough instead of ahead, unlike the observations, and overestimates the intensity and spatial coverage of rainfall associated with 6-9-d AEWs. The observed and simulated co-variability between 3-5-d (6-9-d) AEW activity and daily rainfall is strong (weak) and mostly located south (north) of 15°N. However, the RCM overestimates the spatial coverage of the AEW-rainfall relationship in the longitudinal (latitudinal) direction in the case of 3-5-d (6-9-d) AEWs. Observed and simulated daily intense rainfall events, extracted using a percentile threshold approach, are mostly located south of 15°N during summer. The observed relationship between their frequency of occurrence and active 3-5-d AEWs is maximal west of 8°E, while extends up to southern Chad in both RCM simulations. Their magnitude is also largely overestimated by the RCM, indicating an exaggerated coupling between the wave activity and the convection. Finally, observed and simulated 3-5-d AEWs establish the most favorable synoptic conditions for the development of intense rainfall events over West Africa.

  11. Mapping human resources for eye health in 21 countries of sub-Saharan Africa: current progress towards VISION 2020

    PubMed Central

    2014-01-01

    Background Development of human resources for eye health (HReH) is a major focus of the Global Action Plan 2014 to 2019 to reduce the prevalence of avoidable visual impairment by 25% by the year 2019. The eye health workforce is thought to be much smaller in sub-Saharan Africa than in other regions of the world but data to support this for policy-making is scarce. We collected HReH and cataract surgeries data from 21 countries in sub-Sahara to estimate progress towards key suggested population-based VISION 2020 HReH indicators and cataract surgery rates (CSR) in 2011. Methods Routinely collected data on practitioner and surgery numbers in 2011 was requested from national eye care coordinators via electronic questionnaires. Telephone and e-mail discussions were used to determine data collection strategies that fit the national context and to verify reported data quality. Information was collected on six practitioner cadres: ophthalmologists, cataract surgeons, ophthalmic clinical officers, ophthalmic nurses, optometrists and ‘mid-level refractionists’ and combined with publicly available population data to calculate practitioner to population ratios and CSRs. Associations with development characteristics were conducted using Wilcoxon rank sum tests and Spearman rank correlations. Results HReH data was not easily available. A minority of countries had achieved the suggested VISION 2020 targets in 2011; five countries for ophthalmologists/cataract surgeons, four for ophthalmic nurses/clinical officers and two for CSR. All countries were below target for optometrists, even when other cadres who perform refractions as a primary duty were considered. The regional (sample) ratio for surgeons (ophthalmologists and cataract surgeons) was 2.9 per million population, 5.5 for ophthalmic clinical officers and nurses, 3.7 for optometrists and other refractionists, and 515 for CSR. A positive correlation between GDP and CSR as well as many practitioner ratios was observed

  12. A humid corridor across the Sahara for the migration of early modern humans out of Africa 120,000 years ago.

    PubMed

    Osborne, Anne H; Vance, Derek; Rohling, Eelco J; Barton, Nick; Rogerson, Mike; Fello, Nuri

    2008-10-28

    It is widely accepted that modern humans originated in sub-Saharan Africa approximately 150-200 thousand years ago (ka), but their route of dispersal across the currently hyperarid Sahara remains controversial. Given that the first modern humans north of the Sahara are found in the Levant approximately 120-90 ka, northward dispersal likely occurred during a humid episode in the Sahara within Marine Isotope Stage (MIS) 5e (130-117 ka). The obvious dispersal route, the Nile, may be ruled out by notable differences between archaeological finds in the Nile Valley and the Levant at the critical time. Further west, space-born radar images reveal networks of-now buried-fossil river channels that extend across the desert to the Mediterranean coast, which represent alternative dispersal corridors. These corridors would explain scattered findings at desert oases of Middle Stone Age Aterian lithic industries with bifacial and tanged points that can be linked with industries further to the east and as far north as the Mediterranean coast. Here we present geochemical data that demonstrate that water in these fossil systems derived from the south during wet episodes in general, and penetrated all of the way to the Mediterranean during MIS 5e in particular. This proves the existence of an uninterrupted freshwater corridor across a currently hyperarid region of the Sahara at a key time for early modern human migrations to the north and out of Africa.

  13. A humid corridor across the Sahara for the migration of early modern humans out of Africa 120,000 years ago

    PubMed Central

    Osborne, Anne H.; Vance, Derek; Rohling, Eelco J.; Barton, Nick; Rogerson, Mike; Fello, Nuri

    2008-01-01

    It is widely accepted that modern humans originated in sub-Saharan Africa ≈150–200 thousand years ago (ka), but their route of dispersal across the currently hyperarid Sahara remains controversial. Given that the first modern humans north of the Sahara are found in the Levant ≈120–90 ka, northward dispersal likely occurred during a humid episode in the Sahara within Marine Isotope Stage (MIS) 5e (130–117 ka). The obvious dispersal route, the Nile, may be ruled out by notable differences between archaeological finds in the Nile Valley and the Levant at the critical time. Further west, space-born radar images reveal networks of—now buried—fossil river channels that extend across the desert to the Mediterranean coast, which represent alternative dispersal corridors. These corridors would explain scattered findings at desert oases of Middle Stone Age Aterian lithic industries with bifacial and tanged points that can be linked with industries further to the east and as far north as the Mediterranean coast. Here we present geochemical data that demonstrate that water in these fossil systems derived from the south during wet episodes in general, and penetrated all of the way to the Mediterranean during MIS 5e in particular. This proves the existence of an uninterrupted freshwater corridor across a currently hyperarid region of the Sahara at a key time for early modern human migrations to the north and out of Africa. PMID:18936490

  14. Sensitivity of Boreal-Summer Circulation and Precipitation to Atmospheric Aerosols in Selected Regions: Part I Africa and India

    SciTech Connect

    Sud, Yogesh C.; Wilcox, Eric; Lau, William K.; Walker, Greg K.; Liu, Xiaohong; Nenes, Athanasios; Lee , Dongmin; Kim, K. - M.; Zhou, Yaping; Bhattacharjee, P. S.

    2009-10-23

    Version-4 of the Goddard Earth Observing System (GEOS-4) General Circulation Model (GCM) was employed to assess the influence of potential changes in aerosols on the regional circulation, ambient temperatures, and precipitation in four selected regions: India and Africa (current paper), as well as North and South America (companion paper). Ensemble-simulations were carried out with the GCM to assess the aerosol direct and indirect effects, hereafter ADE and AIE. Each simulation was started from the NCEP-analyzed initial conditions for May 1 and was integrated through May-June-July-August of each year: 1982-1987 to provide an ensemble set of six simulations. In the first set, called the baseline experiment (#1), climatological aerosols were prescribed. The next two experiments (#2 and #3) had two sets of simulations each: one with 2X and another with 1/2X the climatological aerosols over each of the four selected regions. In experiment#2, the anomaly regions were advectively restricted (AR), i.e., the large-scale prognostic fields outside the aerosol anomaly regions were prescribed while in experiment#3, the anomaly regions were advectively Interactive (AI) as is the case in a normal GCM integrations, but with the same aerosols anomalies as in experiment #2. Intercomparisons of circulation, diabatic heating, and precipitation difference fields showed large disparities among the AR and AI simulations, which raised serious questions about the AR assumption, commonly invoked in regional climate simulation studies. Consequently AI simulation mode was chosen for the subsequent studies. Two more experiments (#4 and #5) were performed in the AI mode in which ADE and AIE were activated one at a time. The results showed that ADE and AIE work in concert to make the joint influences larger than sum of each acting alone. Moreover, the ADE and AIE influences were vastly different for the Indian and Africa regions, which suggest an imperative need to include them rationally in

  15. Dermatology and HIV/AIDS in Africa

    PubMed Central

    Hu, Jenny; McKoy, Karen; Papier, Art; Klaus, Sidney; Ryan, Terence; Grossman, Henning; Masenga, Elisante J; Sethi, Aisha; Craft, Noah

    2011-01-01

    Human immunodeficiency virus and the acquired immunodeficiency syndrome (HIV/AIDS) have greatly complicated dermatologic disease and the required care in most regions of Africa. Opportunistic infections, ectoparasites, Kaposi sarcoma, and skin manifestations of systemic infections are exceedingly common in patients with HIV/AIDS. Dermatologists have contributed significantly to our knowledge base about HIV/AIDS and have played an important educational role regarding the clinical manifestations historically. Because of the increased burden of skin disease in Africa due to the HIV/AIDS epidemic we must redouble our efforts to provide dermatology education to care providers in Africa. We review the burden of skin disease in Africa, how it relates to HIV/AIDS and global infectious disease, current educational strategies in Africa to address this need, and suggest potential solutions to move these efforts forward. PMID:21887061

  16. Africa: Prosperous times

    SciTech Connect

    1996-08-01

    Political instability and corruption is the rule, rather than the exception, in Africa`s main producing regions, but exploration and production prospects there are bright and attractive to foreign operators. The paper discusses exploration, drilling, resource development, and production in Nigeria, Libya, Algeria, Egypt, Angola, Congo, Gabon, and Tunisia. The other countries of Africa are briefly mentioned, i.e., Cameroon, Cote D`Ivoire, South Africa, Sudan, Namibia, Equatorial Guinea, Eritrea, Zaire, Mozambique, Ghana, Niger, and Seychelles.

  17. Assessment of projected climate change signals over central Africa based on a multitude of global and regional climate projections

    NASA Astrophysics Data System (ADS)

    Hänsler, Andreas; Saeed, Fahad; Jacob, Daniela

    2013-04-01

    It is well accepted within the scientific community that only a large ensemble of different projections will allow achieving robust climate change information for a specific region. In the framework of the project "Climate changes scenarios for the Congo basin" (funded by the German Ministry for Environment, Nature Conservation and Nuclear Safety) a regional climate change assessment is conducted by the Climate Service Center (CSC) over the greater Congo basin region. The analysis is based on a state-of-the-art multi-model multi-scenario ensemble of global and regional climate change projections. In this ensemble the results of several GCM projections from the CMIP3 and the CMIP5 projects are combined with some of the recently downscaled regional CORDEX-Africa projections. Altogether data from 77 different climate change projections are analysed; separated into 31 projections for a "high" and 46 for a "low" emission scenario. In the study several parameters and indices related to temperature and precipitation are considered for the assessment of projected climate change. The large size of the analyzed ensemble is expected to be useful for not only quantifying the magnitude of projected changes, but also to analyze their robustness as well. Moreover, potential differences between projected changes from GCMs and RCMs can also be analysed.

  18. Assessment of projected climate change signals over central Africa based on a multitude of global and regional climate projections

    NASA Astrophysics Data System (ADS)

    Haensler, A.; Saeed, F.; Jacob, D.

    2013-05-01

    It is well accepted within the scientific community that only a large ensemble of different projections will allow achieving robust climate change information for a specific region. In the framework of the project "Climate changes scenarios for the Congo basin" (funded by the German Ministry for Environment, Nature Conservation and Nuclear Safety) a regional climate change assessment is conducted by the Climate Service Center (CSC) over the greater Congo basin region. The analysis is based on a state-of-the-art multi-model multi-scenario ensemble of global and regional climate change projections. In this ensemble the results of several GCM projections from the CMIP3 and the CMIP5 projects are combined with some of the recently downscaled regional CORDEX-Africa projections. Altogether data from 77 different climate change projections are analysed; separated into 31 projections for a "high" and 46 for a "low" emission scenario. In the study several parameters and indices related to temperature and precipitation are considered for the assessment of projected climate change. The large size of the analyzed ensemble is expected to be useful for not only quantifying the magnitude of projected changes, but also to analyze their robustness as well. Moreover, potential differences between projected changes from GCMs and RCMs can also be analysed.

  19. The Impact of Human Activities on Microbial Quality of Rivers in the Vhembe District, South Africa

    PubMed Central

    Traoré, Afsatou N.; Mulaudzi, Khodani; Chari, Gamuchirai J.E.; Foord, Stefan H.; Mudau, Lutendo S.; Barnard, Tobias G.; Potgieter, Natasha

    2016-01-01

    Background: Water quality testing is dictated by microbial agents found at the time of sampling in reference to their acceptable risk levels. Human activities might contaminate valuable water resources and add to the microbial load present in water bodies. Therefore, the effects of human activities on the microbial quality of rivers collected from twelve catchments in the Vhembe District in South Africa were investigated, with samples analyzed for total coliform (TC) and Eschericha coli (E. coli) contents. Methods: Physical parameters and various human activities were recorded for each sampling site. The Quanti-Tray® method was adopted for the assessment of TC and E. coli contents in the rivers over a two-year period. A multiplex polymerase chain (PCR) method was used to characterize the strains of E. coli found. Results: The microbial quality of the rivers was poor with both TC and E. coli contents found to be over acceptable limits set by the South African Department of Water and Sanitation (DWS). No significant difference (p > 0.05) was detected between TC and E. coli risks in dry and wet seasons. All six pathogenic E. coli strains were identified and Enteroaggregative E. coli (EAEC), atypical Enteropathogenic E. coli (a-EPEC) and Enterotoxigenic E. coli (ETEC) were the most prevalent E. coli strains detected (respectively, 87%, 86% and 83%). Conclusions: The study indicated that contamination in the majority of sampling sites, due to human activities such as car wash, animal grazing and farming, poses health risks to communities using the rivers for various domestic chores. It is therefore recommended that more education by the respective departments is done to avert pollution of rivers and prevent health risks to the communities in the Vhembe District. PMID:27529265

  20. 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.

  1. Modelling the spread of farming in the Bantu-speaking regions of Africa: an archaeology-based phylogeography.

    PubMed

    Russell, Thembi; Silva, Fabio; Steele, James

    2014-01-01

    We use archaeological data and spatial methods to reconstruct the dispersal of farming into areas of sub-Saharan Africa now occupied by Bantu language speakers, and introduce a new large-scale radiocarbon database and a new suite of spatial modelling techniques. We also introduce a method of estimating phylogeographic relationships from archaeologically-modelled dispersal maps, with results produced in a format that enables comparison with linguistic and genetic phylogenies. Several hypotheses are explored. The 'deep split' hypothesis suggests that an early-branching eastern Bantu stream spread around the northern boundary of the equatorial rainforest, but recent linguistic and genetic work tends not to support this. An alternative riverine/littoral hypothesis suggests that rivers and coastlines facilitated the migration of the first farmers/horticulturalists, with some extending this to include rivers through the rainforest as conduits to East Africa. More recently, research has shown that a grassland corridor opened through the rainforest at around 3000-2500 BP, and the possible effect of this on migrating populations is also explored. Our results indicate that rivers and coasts were important dispersal corridors, but do not resolve the debate about a 'Deep Split'. Future work should focus on improving the size, quality and geographical coverage of the archaeological (14)C database; on augmenting the information base to establish descent relationships between archaeological sites and regions based on shared material cultural traits; and on refining the associated physical geographical reconstructions of changing land cover.

  2. Assessment of Regional Climate Models over Côte d'Ivoire and Analysis of Future Projections over West Africa

    NASA Astrophysics Data System (ADS)

    Kouadio, K.; Konare, A.; Diawara, A.; Dje, B. K.; Ajayi, V. O.; Diedhiou, A.

    2015-12-01

    The ability of six Regional Climate Models (RCMs) used in AMMA-ENSEMBLES project is assessed over six meteorological stations in Côte d'Ivoire. The ensemble mean of the models is also used for the prediction of climate change over West Africa. The study focused on two periods: the period 1995-2005, the present-day simulations, is used to evaluate the skills of the models over the country and the years 2010-2013, for assessment of the future climate change scenario used. The results show that the skills of the models vary from one station to another and from one season to another. None of the models considered, presents an excellent performance over the entire country and in all the seasons. Generally, the ensemble mean of all the models presents better results when compared with the observation. These results suggest that the choice of any model for study over the country may depend on the focus of interest: intensity or variability of the rain and also on area of interest. The projection for 2020-2040, future climate change over West Africa shows that the Sahel exhibits a tendency to be drier while wetter Guinean coast is observed

  3. Modelling the Spread of Farming in the Bantu-Speaking Regions of Africa: An Archaeology-Based Phylogeography

    PubMed Central

    Russell, Thembi; Silva, Fabio; Steele, James

    2014-01-01

    We use archaeological data and spatial methods to reconstruct the dispersal of farming into areas of sub-Saharan Africa now occupied by Bantu language speakers, and introduce a new large-scale radiocarbon database and a new suite of spatial modelling techniques. We also introduce a method of estimating phylogeographic relationships from archaeologically-modelled dispersal maps, with results produced in a format that enables comparison with linguistic and genetic phylogenies. Several hypotheses are explored. The ‘deep split’ hypothesis suggests that an early-branching eastern Bantu stream spread around the northern boundary of the equatorial rainforest, but recent linguistic and genetic work tends not to support this. An alternative riverine/littoral hypothesis suggests that rivers and coastlines facilitated the migration of the first farmers/horticulturalists, with some extending this to include rivers through the rainforest as conduits to East Africa. More recently, research has shown that a grassland corridor opened through the rainforest at around 3000–2500 BP, and the possible effect of this on migrating populations is also explored. Our results indicate that rivers and coasts were important dispersal corridors, but do not resolve the debate about a ‘Deep Split’. Future work should focus on improving the size, quality and geographical coverage of the archaeological 14C database; on augmenting the information base to establish descent relationships between archaeological sites and regions based on shared material cultural traits; and on refining the associated physical geographical reconstructions of changing land cover. PMID:24498213

  4. Regional Land Surface Hydrology Impacts from Fire-Induced Surface Albedo Darkening in Northern Sub-Saharan Africa

    NASA Astrophysics Data System (ADS)

    Bolten, J. D.; Gupta, M.; Gatebe, C. K.; Ichoku, C. M.

    2015-12-01

    Land surface hydrology models serve as an effective approach to simulate hydrological processes, especially in areas which lack in situ observational datasets. A key component to constraining the water, energy, and carbon dynamics within these models is land surface albedo because it links these cycles by driving evapotranspiration and also helps characterize soil infiltration behavior. However, most hydrological models estimate the land surface albedo based on generalized climatologic information, which can introduce uncertainty into the surface energy balance processes and water storage availability in the root-zone if done improperly. In particular, changes in surface albedo can have significant effects where dynamic and spatially heterogeneous land surface changes occur due to abrupt land cover changes, such as wildfire. Sub-Saharan Africa is one of the most fire-prone regions of the world. Thus, the current study employs the new parameterization approach based on estimated change of surface albedo due to fires over different land cover types using long term MODIS time series in the catchment-based land surface model to investigate the potential for improving soil moisture and evapotranspiration simulations in fire-prone Northern Sub-Saharan Africa. We also compare the estimated soil moisture based on new and pre-existing baseline parameterization scheme to remotely-sensed observations obtained from satellite-based soil moisture observations from the Advanced Microwave Scanning Radiometer (AMSR-E), the Soil Moisture Ocean Salinity (SMOS), and the recently launched satellite, Soil Moisture Active Passive (SMAP) instruments.

  5. The cost implications of participatory research. Experience of a health services review in a rural region in South Africa

    PubMed

    Doherty; Price

    1998-03-01

    OBJECTIVES: The study objectives were to estimate the total costs incurred by a comprehensive review of primary health care services in a rural region in South Africa, and to determine which of these costs were incurred because of the participatory research techniques employed by the review. DESIGN: The costing study estimated the direct and indirect costs of each component of the review in order to determine total costs. Costs that were linked to participatory research activities were aggregated separately. SETTING: The review that was costed was conducted in an area that included the former 'homeland' KaNgwane and the adjacent areas of 'white' South Africa, in part of what is now known as Mpumalanga Province. SUBJECTS: Not relevant. OUTCOME MEASURES: Direct, indirect, total, research and participation costs were used as outcome measures. RESULTS: Expenditure generated by participatory research techniques was estimated to be almost 14% of the total (direct and indirect) costs. CONCLUSIONS: Despite these costs, participatory research techniques are invaluable in terms of the many benefits they have for a research project. However, because of these costs, it is important that the financing of participatory research should be carefully planned. Projects must budget for the direct costs of participatory techniques, participating organisations and individuals must be committed to bearing the indirect costs of participation, and, increasingly, funders must consider funding these indirect costs. This is important in the South African situation, where public health research relies increasingly on the participation of relevant stakeholders.

  6. The East Africa Oligocene intertrappean beds: Regional distribution, depositional environments and Afro/Arabian mammal dispersals

    NASA Astrophysics Data System (ADS)

    Abbate, Ernesto; Bruni, Piero; Ferretti, Marco Peter; Delmer, Cyrille; Laurenzi, Marinella Ada; Hagos, Miruts; Bedri, Omar; Rook, Lorenzo; Sagri, Mario; Libsekal, Yosief

    2014-11-01

    The extensive outpouring of the Oligocene Trap basalts over eastern Africa and western Arabia was interrupted by a period of quiescence marked by the deposition of terrestrial sediments. These so-called intertrappean beds are often lignitiferous and yield recurrent floras and faunas, sometimes represented by endemic mammals. We intended to highlight the peculiar features of these sedimentary intercalations using a large-scale approach including eastern Africa and the western Arabian peninsula. Starting from a new mapping in the Eritrean highland, the intertrappean beds resulted a continuous level that was a few tens of meters thick and traceable for some tens of kilometers. They consist of fluvial red, green and gray mudstones and siltstones with subordinate channelized pebbly sandstones, and lignite seams. Two new 40Ar-39Ar datings constraint the age of the intertrappean beds between 29.0 Ma and 23.6 Ma. The outcrops near Mendefera have yielded the remains of two proboscidean families, the Deinotheriidae and the Gomphoteriidae. The morphological grade of the two Mendefera proboscideans would suggest a more derived stage than that of representatives of the same families from other Oligocene African sites (e.g., Chilga, Ethiopia). An Oligocene age could be inferred for them. The occurrence of the genus Prodeinotherium at Mai Gobro possibly represents the first occurrence of this taxon, while the Gomphotheirum sp. might represent the oldest occurrence of this taxon in Africa before its dispersal towards Asia and Europe. Proboscideans have also been found in the lowland intertrappean beds of Dogali near Massawa. These sediments were contiguous with the Eritrean highland intertrappean beds during the Oligocene, but are now tectonically displaced from them by two thousand meters of vertical topographical distance. Dogali is also known for the occurrence of possible Deinotheriidae remains and the primitive elephantoid Eritreum. Entering the Ethiopian highland, an

  7. Identification of local selective sweeps in human populations since the exodus from Africa.

    PubMed

    Johansson, Asa; Gyllensten, Ulf

    2008-06-01

    Selection on the human genome has been studied using comparative genomics and SNP architecture in the lineage leading to modern humans. In connection with the African exodus and colonization of other continents, human populations have adapted to a range of different environmental conditions. Using a new method that jointly analyses haplotype block length and allele frequency variation (F(ST)) within and between populations, we have identified chromosomal regions that are candidates for having been affected by local selection. Based on 1.6 million SNPs typed in 71 individuals of African American, European American and Han Chinese descent, we have identified a number of genes and non-coding regions that are candidates for having been subjected to local positive selection during the last 100 000 years. Among these genes are those involved in skin pigmentation (SLC24A5) and diet adaptation (LCT). The list of genes implicated in these local selective sweeps overlap partly with those implicated in other studies of human populations using other methods, but show little overlap with those postulated to have been under selection in the 5-7 myr since the divergence of the ancestors of human and chimpanzee. Our analysis provides focal points in the genome for detailed studies of evolutionary events that have shaped human populations as they explored different regions of the world.

  8. Out of Africa: modern human origins special feature: the spread of modern humans in Europe.

    PubMed

    Hoffecker, John F

    2009-09-22

    The earliest credible evidence of Homo sapiens in Europe is an archaeological proxy in the form of several artifact assemblages (Bohunician) found in South-Central and possibly Eastern Europe, dating to < or =48,000 calibrated radiocarbon years before present (cal BP). They are similar to assemblages probably made by modern humans in the Levant (Emiran) at an earlier date and apparently represent a population movement into the Balkans during a warm climate interval [Greenland Interstadial 12 (GI 12)]. A second population movement may be represented by a diverse set of artifact assemblages (sometimes termed Proto-Aurignacian) found in the Balkans, parts of Southwest Europe, and probably in Eastern Europe, and dating to several brief interstadials (GI 11-GI 9) that preceded the beginning of cold Heinrich Event 4 (HE4) (approximately 40,000 cal BP). They are similar to contemporaneous assemblages made by modern humans in the Levant (Ahmarian). The earliest known human skeletal remains in Europe that may be unequivocally assigned to H. sapiens (Peçstera cu Oase, Romania) date to this time period (approximately 42,000 cal BP) but are not associated with artifacts. After the Campanian Ignimbrite volcanic eruption (40,000 cal BP) and the beginning of HE4, artifact assemblages assigned to the classic Aurignacian, an industry associated with modern human skeletal remains that seems to have developed in Europe, spread throughout the continent.

  9. An Exploration of Public Attitudes Toward LGBTI Rights in the Gauteng City-Region of South Africa.

    PubMed

    Mahomed, Faraaz; Trangoš, Guy

    2016-10-01

    South Africa's legal framework on the rights of sexual minorities is one of the most progressive in the world. Despite this, discrimination and violence against gay and lesbian people continues to be a challenge. Using large-scale survey data gathered in the Gauteng City-Region, this study examines public attitudes related to homosexuality. Most respondents to the survey felt that sexual minorities should have equal rights. However, a considerable proportion of respondents also held negative views toward gay and lesbian individuals, with close to two fifths of respondents believing that homosexuality is against the values of their community, and over 12% of participants holding the view that it is acceptable to be violent toward gays and lesbians. Further analysis also consists of an examination of responses cross-tabulated with the variables of race, gender, age, and education, revealing that younger, well-educated South Africans tend to be the most tolerant, but also exhibiting large variances in attitudes within groups.

  10. Insights from Earth Sciences into Human Evolution studies: The example of prehistoric landscape use in Africa and the Levant

    NASA Astrophysics Data System (ADS)

    Devès, Maud H.; Reynolds, Sally; King, Geoffrey C. P.; Kuebler, Simon; Sturdy, Derek; Godet, Nan

    2015-07-01

    Fossil remains are embedded in a continually evolving landscape. Earth scientists have the methods and approaches to study the processes that shape the landscape at various temporal and spatial scales. Some of these methods can generate insights that are of potential use for researchers in other fields, such as archaeology and palaeoanthropology. Here we present two case studies to illustrate how a broader landscape perspective can provide new insights into the land use by Pliocene hominins in southern Africa, and more recently, by Palaeolithic hominins in the southern Levant. Key landscape attributes can help explain why humans, hominins and the wider animal community exploit certain types of landscapes in predictable ways. Our first case study examines how active tectonics or volcanism appears to be important in creating fertile regions with reliable water sources and complex topography. While relatively easy for agile primates such as hominins to negotiate, zones of complex topography are harder for certain predators and prey animals to traverse. In the second case study, we consider that differences in soil edaphics can exert a major control on animals by supplying or failing to supply necessary trace elements, such as selenium, copper, phosphate and potassium (Henkin et al., 1995). We show that the pattern of trace element distribution can accurately map animal movements between areas of suitable grazing. This predictability could have enabled Levantine humans to ambush megafauna during these seasonal migrations. By studying the landscape attributes around fossil site locations, Earth scientists can offer new insights and perspectives into the past, particularly on the ways in which the inhabitants would have used their landscapes.

  11. A humid corridor across the Sahara for the migration "Out of Africa" of early modern humans 120,000 years ago

    NASA Astrophysics Data System (ADS)

    Osborne, A. H.; Vance, D.; Rohling, E. J.; Barton, N.; Rogerson, M.; Fello, N.

    2008-12-01

    a currently hyperarid region of the Sahara at a key time for early modern human migrations to the north and out of Africa. 1Scrivner, A.E. et al. (2004) Geology 32, 565-568.

  12. Tropospheric Ozone Increases over the Southern Africa Region: Bellwether for Rapid Growth in Southern Hemisphere Pollution?

    NASA Technical Reports Server (NTRS)

    Thompson, Anne M.; Balashov, Nikolay V.; Witte, J. C.; Coetzee, J. G. R.; Thouret, V.; Posny, F.

    2014-01-01

    Increases in free-tropospheric (FT) ozone based on ozonesonde records from the early 1990s through 2008 over two subtropical stations, Irene (near Pretoria, South Africa) and Réunion (21 deg. S, 55 deg. E; approx. 2800 km NE of Irene in the Indian Ocean), have been reported. Over Irene a large increase in the urban-influenced boundary layer (BL, 1.5-4 km) was also observed during the 18-year period, equivalent to 30%decade-1. Here we show that the Irene BL trend is at least partly due to a gradual change in the sonde launch times from early morning to the midday period. The FT ozone profiles over Irene in 1990-2007 are re-examined, filling in a 1995-1999 gap with ozone profiles taken during the Measurements of Ozone by Airbus In-service Aircraft (MOZAIC) project over nearby Johannesburg. A multivariate regression model that accounts for the annual ozone cycle, El Niño-Southern Oscillation (ENSO) and possible tropopause changes was applied to monthly averaged Irene data from 4 to 11 km and to 1992-2011 Réunion sonde data from 4 to 15 km. Statistically significant trends appear predominantly in the middle and upper troposphere (UT; 4-11 km over Irene, 4-15 km over Réunion) in winter (June-August), with increases 1 ppbv yr(exp. -1) over Irene and approx. 2 ppbv yr(exp. -1) over Réunion. These changes are equivalent to approx. 25 and 35-45%decade( exp. -1), respectively. Both stations also display smaller positive trends in summer, with a 45%decade(exp. -1) ozone increase near the tropopause over Réunion in December. To explain the ozone increases, we investigated a time series of dynamical markers, e.g., potential vorticity (PV) at 330-350 K. PV affects UT ozone over Irene in November-December but displays little relationship with ozone over Réunion. A more likely reason for wintertime FT ozone increases over Irene and Réunion appears to be long-range transport of growing pollution in the Southern Hemisphere. The ozone increases are consistent with trajectory

  13. Water Use and Management in Semiarid Regions - A Distributed Modelling Approach in the Verlorenvlei Catchment, South Africa

    NASA Astrophysics Data System (ADS)

    Fleischer, Melanie; Kralisch, Sven; Fink, Manfred; Pfennig, Björn; Butchart-Kuhlmann, Daniel; Meinhardt, Markus; de Clercq, Willem

    2016-04-01

    Hydrological modelling is a useful method to predict water availability and environmental impacts in a range of climate and land use change scenarios. One of the major challenges to accurate predictions using hydrological modelling in semi-arid areas is the high temporal and spatial variability of rainfall events and the associated uncertainty of related process parameters. Limited and often unreliable climate observations can cause additional problems. These particular circumstances are well documented for many catchments in the world, including semi-arid parts of South Africa. An accurate assessment of water quality and quantity is however crucial for sustainable water resource management, which is often difficult under changing environmental conditions such as climate and land use change. This situation can be found in the Verlorenvlei catchment, a part of the Sandveld area located in the Western Cape region of South Africa. Extensive dry periods in combination with an increasing domestic water demand, expanding irrigation agriculture and expected reducing rainfall due to climate change present a challenging setup for water management in this region. The catchment is a highly sensitive area with one of the most important estuary systems in the Western Cape region, containing significant natural wetlands with high biodiversity and numerous endemic species. With very limited surface water resources, most settlements and irrigation systems in the region are mainly dependent on groundwater. As a result of the particular conditions, the use of improved management techniques, such as centre pivot irrigation and contour-bank farming, are necessary. The distributed, process-oriented hydrological modelling system JAMS/J2000 is used and evaluated to assess water availability within the catchment under different climate and land-use change scenarios. The first phase has involved configuring the model to accurately represent the specific natural conditions of the

  14. 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

  15. Human-carnivore coexistence on communal land bordering the greater Kruger area, South Africa.

    PubMed

    Lagendijk, D D Georgette; Gusset, Markus

    2008-12-01

    The aim of this study was to assess the potential for coexistence between rural people (living adjacent to a protected area) and predators (from the same area) ranging onto communal land. Ninety members of local communities bordering Manyeleti Game Reserve, which is contiguous with Kruger National Park, South Africa were interviewed. Respondents expressed diverging attitudes toward predators, which were more favorable among participants with higher education. Negative views were particularly due to fear of human and livestock losses, especially to lions, Panthera leo. Lions were thought to be the most abundant predator both within and outside the reserve. Lions were also the best known predator and were most often held responsible for killing livestock. Despite these livestock losses and a lack of conservation education, most participants voiced favorable opinions about large carnivore conservation, as predators were considered an integral part of the respondents' natural heritage. Thanks to this cultural tolerance and also because of a largely accepted management policy regarding predator control, large carnivores and people can coexist in the vicinity of Kruger National Park.

  16. Human Carnivore Coexistence on Communal Land Bordering the Greater Kruger Area, South Africa

    NASA Astrophysics Data System (ADS)

    Lagendijk, D. D. Georgette; Gusset, Markus

    2008-12-01

    The aim of this study was to assess the potential for coexistence between rural people (living adjacent to a protected area) and predators (from the same area) ranging onto communal land. Ninety members of local communities bordering Manyeleti Game Reserve, which is contiguous with Kruger National Park, South Africa were interviewed. Respondents expressed diverging attitudes toward predators, which were more favorable among participants with higher education. Negative views were particularly due to fear of human and livestock losses, especially to lions, Panthera leo. Lions were thought to be the most abundant predator both within and outside the reserve. Lions were also the best known predator and were most often held responsible for killing livestock. Despite these livestock losses and a lack of conservation education, most participants voiced favorable opinions about large carnivore conservation, as predators were considered an integral part of the respondents’ natural heritage. Thanks to this cultural tolerance and also because of a largely accepted management policy regarding predator control, large carnivores and people can coexist in the vicinity of Kruger National Park.

  17. The UNESCO Universal Declaration on Bioethics and Human Rights: perspectives from Kenya and South Africa.

    PubMed

    Langlois, Adèle

    2008-03-01

    In October 2005, UNESCO (the United Nations Educational, Scientific and Cultural Organization) adopted the Universal Declaration on Bioethics and Human Rights. This was the culmination of nearly 2 years of deliberations and negotiations. As a non-binding instrument, the declaration must be incorporated by UNESCO's member states into their national laws, regulations or policies in order to take effect. Based on documentary evidence and data from interviews, this paper compares the declaration's universal principles with national bioethics guidelines and practice in Kenya and South Africa. It concentrates on areas of particular relevance to developing countries, such as protection of vulnerable persons and social responsibility. The comparison demonstrates the need for universal principles to be contextualised before they can be applied in a meaningful sense at national level. The paper also assesses the 'added value' of the declaration in terms of biomedical research ethics, given that there are already well-established international instruments on bioethics, namely the World Medical Association Declaration of Helsinki and the CIOMS (Council for International Organizations of Medical Sciences) guidelines on biomedical research. It may be that the added value lies as much in the follow-up capacity building activities being initiated by UNESCO as in the document itself.

  18. The negative impacts of human activities in the eastern African region: an international waters perspective.

    PubMed

    Payet, Rolph; Obura, David

    2004-02-01

    The complex interactions between human activities and the environment at the interface of land and water is analyzed with a focus on the Somali Current (East Africa), and Indian Ocean Island States, subregions of the Global International Waters Assessment (GIWA). These 2 subregions contain some of the world's richest ecosystems, including the high biodiversity forests of Madagascar and the diverse coastal habitats of the eastern African coast. These ecosystems support local communities and national and regional economies. Current and future degradation of these systems, from water basins to continental shelves, affects the livelihoods and sustainability of the countries in the region, and long-term efforts to reduce poverty. The assessments determined that pollution and climate change are the primary environmental and social concerns in the Islands of the Indian Ocean, while freshwater shortage and unsustainable exploitation of fisheries and other living resources are the primary environmental and social concerns in East Africa. The GIWA approach, through assessing root causes of environmental concerns, enables the development of policy approaches for mitigating environmental degradation. This paper explores policy frameworks for mitigating the impacts, and reducing the drivers, of 3 environmental concerns--freshwater shortage; solid waste pollution; and climate change--addressing social and institutional causes and effects, and linking the subregions to broad international frameworks. The common theme in all 3 case studies is the need to develop integrated ecosystem and international waters policies, and mechanisms to manage conflicting interests and to limit threats to natural processes.

  19. New and interesting species of the genus Muelleria (Bacillariophyta) from the Antarctic region and South Africa

    USGS Publications Warehouse

    Van De Vijver, B.; Mataloni, G.; Stanish, L.; Spaulding, S.A.

    2010-01-01

    During a survey of the terrestrial diatom flora of some sub-Antarctic islands in the southern Indian and Atlantic Oceans and of the Antarctic continent, more than 15 taxa belonging to the genus Muelleria were observed. Nine of these taxa are described as new species using light and scanning electron microscopy. Comments are made on their systematic position and how they are distinguished from other species in the genus. Additionally, two previously unrecognized taxa within the genus were discovered in samples from South Africa. One of these, Muelleria taylorii Van de Vijver & Cocquyt sp. nov., is new to science; the other, Muelleria vandermerwei (Cholnoky) Van de Vijver & Cocquyt nov. comb., had been included in the genus Diploneis. The large number of new Muelleria taxa on the (sub)-Antarctic locations is not surprising. Species in Muelleria occur rarely in collections; in many habitats, it is unusual to find more than 1-2 valves in any slide preparation. As a result, records are scarce. The practice of "force-fitting" (shoehorning) specimens into descriptions from common taxonomic keys (and species drift) results in European species, such as M. gibbula and M. linearis, being applied to Antarctic forms in ecological studies. Finally, the typical terrestrial habitats of soils, mosses and ephemeral water bodies of most of these taxa have been poorly studied in the past.

  20. A review of mercury in Lake Victoria, East Africa: implications for human and ecosystem health.

    PubMed

    Campbell, Linda; Dixon, D G; Hecky, R E

    2003-01-01

    Lake Victoria, East Africa, has been the site of many recent studies measuring mercury (Hg) concentrations in water, fish, sediment, soil, and humans. Most of these studies were motivated by concerns about Hg contamination from processing of gold ore on the southern shores. Total Hg (THg) concentrations in fish were usually below permissible World Health Organization (WHO) concentrations and international marketing limits and do not threaten the lucrative export industry. Nile perch 3-10 kg and most >10 kg had THg concentrations above the WHO threshold concentrations for at-risk groups (200 ng/g). Elevated THg concentrations in large Nile perch are not of major concern because Nile perch are rarely consumed by the people living on Lake Victoria and very large Nile perch are becoming increasingly rare in catches. Water THg concentrations were below Canadian drinking water guidelines but were elevated relative to those in the northern Great Lakes. Sediment and soil THg concentrations were within inter-national guidelines and are comparable to those in northern latitudes but are lower than those in the Amazon basin. Biomass burning and soil erosion are estimated to be the major sources of THg for the lake and probably constitute a larger source of THg than gold mining in Tanzania.THg concentrations in urine and hair from human volunteers indicate that while gold miners and frequent skin-bleaching cream users are at risk of inorganic mercury poisoning, the rest of the population, including fishermen, is not. Human exposure assessments demonstrated that fish consumption and soil geophagy constitute major sources of THg for humans, but the total estimated daily intake of THg was below the Health Canada tolerable daily intake (TDI) limits. The use of beauty creams containing high inorganic Hg concentrations, however, caused the estimated THg exposure to exceed the TDI. The high THg content in the hair of regular cream users supports this assessment. The nutritional

  1. Regional Higher Education Reform Initiatives in Africa: A Comparative Analysis with the Bologna Process

    ERIC Educational Resources Information Center

    Woldegiorgis, Emnet Tadesse; Jonck, Petronella; Goujon, Anne

    2015-01-01

    Europe's Bologna Process has been identified as a pioneering approach in regional cooperation with respect to the area of higher education. To address the challenges of African higher education, policymakers are recommending regional cooperation that uses the Bologna Process as a model. Based on these recommendations, the African Union Commission…

  2. Desert dust impacts on human health: an alarming worldwide reality and a need for studies in West Africa

    NASA Astrophysics Data System (ADS)

    de Longueville, Florence; Ozer, Pierre; Doumbia, Seydou; Henry, Sabine

    2013-01-01

    High desert dust concentrations raise concerns about adverse health effects on human populations. Based on a systematic literature review, this paper aims to learn more about the relationship between desert dust and human health in the world and to analyse the place of West Africa as a study area of interest. Papers focussing on the potential relationship between dust and health and showing quantitative analyses, published between January 1999 and September 2011, were identified using the ISI Web of Knowledge database ( N = 50). A number of adverse health effects, including respiratory, cardiovascular and cardiopulmonary diseases, are associated with dust. This survey highlights obvious dust impacts on human health independently of the study area, health outcomes and method. Moreover, it reveals an imbalance between the areas most exposed to dust and the areas most studied in terms of health effects. None of these studies has been conducted in West Africa, despite the proximity of the Sahara, which produces about half of the yearly global mineral dust. In view of the alarming results in many parts of the world (Asia, Europe, America), this paper concludes by stressing the importance of carrying out impact studies of Saharan dust in West Africa, where dust events are more frequent and intense than anywhere else.

  3. Human health improvement in Sub-Saharan Africa through integrated management of arthropod transmitted diseases and natural resources.

    PubMed

    Baumgärtner, J; Bieri, M; Buffoni, G; Gilioli, G; Gopalan, H; Greiling, J; Tikubet, G; Van Schayk, I

    2001-01-01

    A concept of an ecosystem approach to human health improvement in Sub-Saharan Africa is presented here. Three factors mainly affect the physical condition of the human body: the abiotic environment, vector-transmitted diseases, and natural resources. Our concept relies on ecological principles embedded in a social context and identifies three sets of subsystems for study and management: human disease subsystems, natural resource subsystems, and decision-support subsystems. To control human diseases and to secure food from resource subsystems including livestock or crops, integrated preventive approaches are preferred over exclusively curative and sectorial approaches. Environmental sustainability - the basis for managing matter and water flows - contributes to a healthy human environment and constitutes the basis for social sustainability. For planning and implementation of the human health improvement scheme, participatory decision-support subsystems adapted to the local conditions need to be designed through institutional arrangements. The applicability of this scheme is demonstrated in urban and rural Ethiopia.

  4. Implementation of Information Communication Technology in the Teaching/Learning Process for Sustainable Development of Adults in West Africa Sub Sahara Region

    ERIC Educational Resources Information Center

    Nwobi, Anthonia; Ngozi, Ugwuoke; Rufina, Nwachukwu; Ogbonnaya, Kingsley A.

    2016-01-01

    This study examines the implementation of information technology in the teaching/learning process for sustainable development of adults in West Africa Sub Sahara Region (WASSR). Three research questions and two hypotheses guided the study. The population for the study was 3071 participants and instructors drawn from 10 education centres that were…

  5. Regional aerosol deposition in human upper airways

    SciTech Connect

    Swift, D.L.

    1990-11-01

    During the current reporting period experimental studies of aerosol deposition in replicate NOPL airways have carried out. A replicate model of a 4 week old infant nasal passage was constructed from MR scans. The model completes the age range from newborn'' to 4 years, there now being one child model for 4 different ages. Deposition studies have been performed with unattached radon progeny aerosols in collaboration with ITRI, Albuquerque, NM and NRPB, Chilton, UK. Overall measurements have been performed in adult and child nasal airways indicating that the child nasal passage was slightly more efficient than the adult in removing 1 nm particles at corresponding flow rates. A similar weak dependence on flow rate was observed. Local deposition studies in an adult nasal model indicated predominant deposition in the anterior region during inspiratory flow, but measurable deposition was found throughout the model. The deposition pattern during expiration was reverse, greater deposition being observed in the posterior region. Local deposition studies of attached progeny aerosol size (100--200 nm) were performed in adult and child nasal models using technigas'' and a gamma scintillation camera. Similar to the unattached size, deposition occurred throughout the models, but was greater in the anterior region.

  6. MtDNA control region variation affirms diversity and deep sub-structure in populations from southern Africa

    PubMed Central

    2013-01-01

    Background The current San and Khoe populations are remnant groups of a much larger and widely dispersed population of hunter-gatherers and pastoralists, who had exclusive occupation of southern Africa before the influx of Bantu-speakers from 2 ka (ka = kilo annum [thousand years] old/ago) and sea-borne immigrants within the last 350 years. Here we use mitochondrial DNA (mtDNA) to examine the population structure of various San and Khoe groups, including seven different Khoe-San groups (Ju/’hoansi, !Xun, /Gui+//Gana, Khwe, ≠Khomani, Nama and Karretjie People), three different Coloured groups and seven other comparative groups. MtDNA hyper variable segments I and II (HVS I and HVS II) together with selected mtDNA coding region SNPs were used to assign 538 individuals to 18 haplogroups encompassing 245 unique haplotypes. Data were further analyzed to assess haplogroup histories and the genetic affinities of the various San, Khoe and Coloured populations. Where possible, we tentatively contextualize the genetic trends through time against key trends known from the archaeological record. Results The most striking observation from this study was the high frequencies of the oldest mtDNA haplogroups (L0d and L0k) that can be traced back in time to ~100 ka, found at high frequencies in Khoe-San and sampled Coloured groups. Furthermore, the L0d/k sub-haplogroups were differentially distributed in the different Khoe-San and Coloured groups and had different signals of expansion, which suggested different associated demographic histories. When populations were compared to each other, San groups from the northern parts of southern Africa (Ju speaking: !Xun, Ju/’hoansi and Khoe-speaking: /Gui+//Gana) grouped together and southern groups (historically Tuu speaking: ≠Khomani and Karretjie People and some Coloured groups) grouped together. The Khoe group (Nama) clustered with the southern Khoe-San and Coloured groups. The Khwe mtDNA profile was very different from other

  7. WASCAL - West African Science Service Center on Climate Change and Adapted Land Use Regional Climate Simulations and Land-Atmosphere Simulations for West Africa at DKRZ and elsewhere

    NASA Astrophysics Data System (ADS)

    Hamann, Ilse; Arnault, Joel; Bliefernicht, Jan; Klein, Cornelia; Heinzeller, Dominikus; Kunstmann, Harald

    2014-05-01

    Changing climate and hydro-meteorological boundary conditions are among the most severe challenges to Africa in the 21st century. In particular West Africa faces an urgent need to develop effective adaptation and mitigation strategies to cope with negative impacts on humans and environment due to climate change, increased hydro-meteorological variability and land use changes. To help meet these challenges, the German Federal Ministry of Education and Research (BMBF) started an initiative with institutions in Germany and West African countries to establish together a West African Science Service Center on Climate Change and Adapted Land Use (WASCAL). This activity is accompanied by an establishment of trans-boundary observation networks, an interdisciplinary core research program and graduate research programs on climate change and related issues for strengthening the analytical capabilities of the Science Service Center. A key research activity of the WASCAL Competence Center is the provision of regional climate simulations in a fine spatio-temporal resolution for the core research sites of WASCAL for the present and the near future. The climate information is needed for subsequent local climate impact studies in agriculture, water resources and further socio-economic sectors. The simulation experiments are performed using regional climate models such as COSMO-CLM, RegCM and WRF and statistical techniques for a further refinement of the projections. The core research sites of WASCAL are located in the Sudanian Savannah belt in Northern Ghana, Southern Burkina Faso and Northern Benin. The climate in this region is semi-arid with six rainy months. Due to the strong population growth in West Africa, many areas of the Sudanian Savannah have been already converted to farmland since the majority of the people are living directly or indirectly from the income produced in agriculture. The simulation experiments of the Competence Center and the Core Research Program are

  8. 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

  9. [Sudden infant death and sickle cell anemia in the Sahel region of Africa].

    PubMed

    Vix, J; Buguet, A; Straboni, S; Beidari, H

    1987-01-01

    The authors investigated the incidence of sudden infant death syndrome (S.I.D.S.) in families of government employees who benefited of free health care. Out of approximately 400 families with around 2000 children, 29 reported at least one infant death meeting the chosen criteria for S.I.D.S. A total of 41 children, mostly males, died between 1 day and 30 months of age, amongst the 149 children born in these families; most of them died during the first 3 months of life. The mothers were generally house wives, aged 26.2 +/- 1.0 years. Sickle cell trait was found in at least one parent of 21 families. In the other 8 families, 11 out of 38 children died, giving a prevalence rate of 6.9/1000 live births for S.I.D.S. in the healthy population. In the sickle cell trait population, the prevalence rate for S.I.D.S. reached 75.0/1000 live births, the prevalence of sickle cell anemia being about 20% in Niger. When very strict criteria were used for diagnosing S.I.D.S., the prevalence rate was 2.5/1000 and 40/1000 live births in the healthy and the sickle trait populations respectively. This study is the first attempt to determine the place of S.I.D.S. in the infant mortality rate in Sahelian Africa. In families with sickle cell disease, the risk of S.I.D.S. was 11.5 times greater than in healthy families. The role of sleep apnea as a cause of S.I.D.S. is discussed. It may represent a common cause of death in both healthy families at risk and sickle cell trait families.

  10. Predicting human age using regional morphometry and inter-regional morphological similarity

    NASA Astrophysics Data System (ADS)

    Wang, Xun-Heng; Li, Lihua

    2016-03-01

    The goal of this study is predicting human age using neuro-metrics derived from structural MRI, as well as investigating the relationships between age and predictive neuro-metrics. To this end, a cohort of healthy subjects were recruited from 1000 Functional Connectomes Project. The ages of the participations were ranging from 7 to 83 (36.17+/-20.46). The structural MRI for each subject was preprocessed using FreeSurfer, resulting in regional cortical thickness, mean curvature, regional volume and regional surface area for 148 anatomical parcellations. The individual age was predicted from the combination of regional and inter-regional neuro-metrics. The prediction accuracy is r = 0.835, p < 0.00001, evaluated by Pearson correlation coefficient between predicted ages and actual ages. Moreover, the LASSO linear regression also found certain predictive features, most of which were inter-regional features. The turning-point of the developmental trajectories in human brain was around 40 years old based on regional cortical thickness. In conclusion, structural MRI could be potential biomarkers for the aging in human brain. The human age could be successfully predicted from the combination of regional morphometry and inter-regional morphological similarity. The inter-regional measures could be beneficial to investigating human brain connectome.

  11. The Challenge of Drug Trafficking to Democratic Governance and Human Security in West Africa

    DTIC Science & Technology

    2013-05-01

    particularly Nigerians and Ghanaians, have been involved in the global drug trade for several decades, first with cannabis and later with heroin...global drug trade for several decades, first with cannabis and later with heroin. The problem has worsened to the point that these networks rep...independence economies of West Africa were characterized by a va- riety of illicit, shadow economies. Cannabis traffick- ing in West Africa was documented

  12. Earthquake Hazard and Risk in Sub-Saharan Africa: current status of the Global Earthquake model (GEM) initiative in the region

    NASA Astrophysics Data System (ADS)

    Ayele, Atalay; Midzi, Vunganai; Ateba, Bekoa; Mulabisana, Thifhelimbilu; Marimira, Kwangwari; Hlatywayo, Dumisani J.; Akpan, Ofonime; Amponsah, Paulina; Georges, Tuluka M.; Durrheim, Ray

    2013-04-01

    Large magnitude earthquakes have been observed in Sub-Saharan Africa in the recent past, such as the Machaze event of 2006 (Mw, 7.0) in Mozambique and the 2009 Karonga earthquake (Mw 6.2) in Malawi. The December 13, 1910 earthquake (Ms = 7.3) in the Rukwa rift (Tanzania) is the largest of all instrumentally recorded events known to have occurred in East Africa. The overall earthquake hazard in the region is on the lower side compared to other earthquake prone areas in the globe. However, the risk level is high enough for it to receive attention of the African governments and the donor community. The latest earthquake hazard map for the sub-Saharan Africa was done in 1999 and updating is long overdue as several development activities in the construction industry is booming allover sub-Saharan Africa. To this effect, regional seismologists are working together under the GEM (Global Earthquake Model) framework to improve incomplete, inhomogeneous and uncertain catalogues. The working group is also contributing to the UNESCO-IGCP (SIDA) 601 project and assessing all possible sources of data for the catalogue as well as for the seismotectonic characteristics that will help to develop a reasonable hazard model in the region. In the current progress, it is noted that the region is more seismically active than we thought. This demands the coordinated effort of the regional experts to systematically compile all available information for a better output so as to mitigate earthquake risk in the sub-Saharan Africa.

  13. Regional aerosol deposition in human upper airways

    SciTech Connect

    Swift, D.L.

    1991-11-01

    During the current report experimental studies of upper respiratory deposition of radon progeny aerosols and stimulant aerosols were carried out in replicate casts of nasal and oral passages of adults and children. Additionally, preliminary studies of nasal passage deposition of unattached Po{sup 218} particles was carried out in four human subjects. Data on nasal inspiratory deposition in replicate models of adults and infants from three collaborating laboratories were compared and a best-fit curve of deposition efficiency for both attached and unattached particles was obtained, showing excellent inter-laboratory agreement. This curve demonstrates that nasal inspiratory deposition of radon progeny is weakly dependent upon flow rate over physiologically realistic ranges of flow, does not show a significant age effect, and is relatively independent of nasal passage dimensions for a given age range. Improved replicate models of the human adult oral passage extending to the mid-trachea were constructed for medium and higher flow mouth breathing states; these models were used to assess the deposition of unattached Po{sup 218} particles during oronasal breathing in the oral passage and demonstrated lower deposition efficiency than the nasal passage. Measurements of both Po{sup 218} particle and attached fraction particle size deposition were performed in replicate nasal passage of a four week old infant. 5 refs., 1 fig.

  14. Regional Climate Simulations with COSMO-CLM for West Africa using three different soil-vegetation-atmosphere-transfer (SVAT) module

    NASA Astrophysics Data System (ADS)

    Breil, Marcus; Panitz, Hans-Jürgen

    2014-05-01

    Climate predictions on decadal timescales constitute a new field of research, closing the gap between short-term and seasonal weather predictions and long-term climate projections. Therefore, the Federal Ministry of Education and Research in Germany (BMBF) has recently funded the research program MiKlip (Mittelfristige Klimaprognosen), which aims to create a model system that can provide reliable decadal climate forecasts. Recent studies have suggested that one region with high potential decadal predictability is West Africa. Therefore, the project DEPARTURE (DEcadal Prediction of African Rainfall and ATlantic HURricanE Activity) was established within the MiKlip program to assess the feasibility and the potential added value of regional decadal climate predictions for West Africa. To quantify the potential decadal climate predictability, a multi-model approach with the three different regional climate models REMO, WRF and COSMO-CLM (CCLM) will be realized. The presented research will contribute to DEPARTURE by performing hindcast ensemble simulations with CCLM, driven by global decadal MPI-ESM-LR simulations. Thereby, one focus is on the dynamic soil-vegetation-climate interaction on decadal timescales. Recent studies indicate that there are significant feedbacks between the land-surface and the atmosphere, which might influence the decadal climate variability substantially. To investigate this connection, two different SVATs (Community Land Model (CLM), and VEG3D) will be coupled with the CCLM, replacing TERRA_ML, the standard SVAT implemented in CCLM. Thus, sensitive model parameters shall be identified, whereby the understanding of important processes might be improved. As a first step, TERRA_ML is substituted by VEG3D, a SVAT developed at the IMK-TRO, Karlsruhe, Germany. Compared to TERRA_ML, VEG3D includes an explicit vegetation layer by using a big leaf approach, inducing higher correlations with observations as it has been shown in previous studies. The

  15. Climate predictors of the spatial distribution of human plague cases in the West Nile region of Uganda.

    PubMed

    MacMillan, Katherine; Monaghan, Andrew J; Apangu, Titus; Griffith, Kevin S; Mead, Paul S; Acayo, Sarah; Acidri, Rogers; Moore, Sean M; Mpanga, Joseph Tendo; Enscore, Russel E; Gage, Kenneth L; Eisen, Rebecca J

    2012-03-01

    East Africa has been identified as a region where vector-borne and zoonotic diseases are most likely to emerge or re-emerge and where morbidity and mortality from these diseases is significant. Understanding when and where humans are most likely to be exposed to vector-borne and zoonotic disease agents in this region can aid in targeting limited prevention and control resources. Often, spatial and temporal distributions of vectors and vector-borne disease agents are predictable based on climatic variables. However, because of coarse meteorological observation networks, appropriately scaled and accurate climate data are often lacking for Africa. Here, we use a recently developed 10-year gridded meteorological dataset from the Advanced Weather Research and Forecasting Model to identify climatic variables predictive of the spatial distribution of human plague cases in the West Nile region of Uganda. Our logistic regression model revealed that within high elevation sites (above 1,300 m), plague risk was positively associated with rainfall during the months of February, October, and November and negatively associated with rainfall during the month of June. These findings suggest that areas that receive increased but not continuous rainfall provide ecologically conducive conditions for Yersinia pestis transmission in this region. This study serves as a foundation for similar modeling efforts of other vector-borne and zoonotic disease in regions with sparse observational meteorologic networks.

  16. A survey of the Cape Floristic Region of South Africa for the presence of cyst nematodes (Nematoda: Heteroderidae).

    PubMed

    Knoetze, Rinus; Swart, Antoinette

    2014-12-09

    A survey was performed to detect the presence of cyst nematodes in the Cape Floristic Region of South Africa. Soil was collected in the rhizosphere of the dominant plant species within blocks of indigenous vegetation and cysts were extracted from them. A total of 81 blocks of indigenous vegetation were sampled as described. Cysts were detected in 7 of these samples, representing 6 different vegetation types. One set of primers was used to amplify the ITS regions from these cysts, including the 5.8S ribosomal gene, as well as short parts of the 18S and 28S ribosomal genes. ITS-rDNA sequences from the indigenous isolates were aligned with selected sequences of other species from the Heteroderidae. Phylogenetic analyses to resolve the relationships between indigenous isolates and selected representatives of the Heteroderidae were conducted using the Maximum Parsimony method. The consensus tree resulting from alignment of the circumfenestrate cysts revealed that isolates SK18, WK1 and WK26 are included in a clade of Globodera species that parasitise non-solanaceous plants, forming a monophyletic group with G. millefolii, G. artemisiae, and an unidentified Globodera sp. from Portugal. In a tree resulting from the alignment of the Heterodera spp., isolates OK14 and WK2 are included in the Afenestrata group, forming a monophyletic group with H. orientalis.This survey unearthed at least four potentially new species of cyst nematodes, which may prove invaluable for the study of the evolution and biogeography of the group.

  17. 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.

  18. 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…

  19. Effect of HIV Infection on Human Papillomavirus Types Causing Invasive Cervical Cancer in Africa

    PubMed Central

    de Vuyst, Hugo; Tenet, Vanessa; Plummer, Martyn; Tully, Stephen; Franceschi, Silvia

    2016-01-01

    Objectives: HIV infection is known to worsen the outcome of cervical human papillomavirus (HPV) infection and may do so differentially by HPV type. Design: Twenty-one studies were included in a meta-analysis of invasive cervical cancers (ICC) among women infected with HIV in Africa. Method: Type-specific HPV DNA prevalence was compared with data from a similar meta-analysis of HIV-negative ICC using prevalence ratios (PR). Results: HPV detection was similar in 770 HIV-positive (91.2%) and 3846 HIV-negative (89.6%) ICC, but HIV-positive ICC harbored significantly more multiple HPV infections (PR = 1.75, 95% confidence intervals: 1.18 to 2.58), which were significantly more prevalent in ICC tested from cells than from biopsies. HPV16 was the most frequently detected type in HIV-positive ICC (42.5%), followed by HPV18 (22.2%), HPV45 (14.4%), and HPV35 (7.1%). Nevertheless, HIV-positive ICC were significantly less frequently infected with HPV16 than HIV-negative ICC (PR = 0.88, 95% confidence intervals: 0.79 to 0.99). Other high-risk types were significantly more prevalent in HIV-positive ICC, but only for HPV18 was there a significantly higher prevalence of both single and multiple infections in HIV-positive ICC. Increases for other high-risk types were primarily accounted for by multiple infections. The proportion of HPV-positive ICC estimated attributable to HPV16/18 (71.8% in HIV positive, 73.4% in HIV negative) or HPV16/18/31/33/45/52/58 (88.8%, 89.5%) was not affected by HIV. Conclusions: HIV alters the relative carcinogenicity of HPV types, but prophylactic HPV16/18 vaccines may nevertheless prevent a similar proportion of ICC, irrespective of HIV infection. PMID:27331659

  20. Rare earth elements upon assessment of reasons of the geophagy in Sikhote-Alin region (Russian Federation), Africa and other world regions.

    PubMed

    Panichev, Alexander M; Popov, Vladimir K; Chekryzhov, Igor Yu; Seryodkin, Ivan V; Stolyarova, Tatiana A; Zakusin, Sergey V; Sergievich, Alexandr A; Khoroshikh, Pavel P

    2016-12-01

    Rocks eaten by wild animals on the Bolshoy Shanduyskiy kudur in the Sikhote-Alin region (Russian Federation) are zeolite-clay mineral complexes-products of weathering of zeolitized vitric tuffs of rhyolite composition, deposited in aqueous medium within the volcanic caldera of about 55 million years ago. By composition of rock-forming oxides, the tuffs refer to high-potassium calc-alkaline series. In trace elements of most favorite kudurites of the Bolshoy Shanduyskiy kudur, there are significantly increased contents of most of rare earth elements (2-5 times in comparison with surrounding rocks). The results of our analysis of geological and geochemical data on kudurs and kudurites in another part of the Sikhote-Alin, as well as on other regions of the world (particularly, in Africa and Indonesia), taking into account new data on the prevalence of rare earth elements in living matter and their medical and biological properties, enable us to consider the version of causal connection of the geophagy with rare earth elements.

  1. Human Factor Management in a Region Under Industrialization - A Concept.

    ERIC Educational Resources Information Center

    Muszynski, Marek; Kowalewski, Andrzej

    Numerous studies conducted by the Committee for Studies on Regions under Industrialization of the Polish Academy of Sciences provide the basis for historical analysis and regional comparison relative to concept formation, program guidelines, and program implementation procedures for rational human factor management. The exhaustion of Poland's…

  2. Nature and distribution of geological domains at the Africa-Eurasia plate boundary off SW Iberia and regional geodynamic implications

    NASA Astrophysics Data System (ADS)

    Martínez-Loriente, Sara; Sallarès, Valentí; Gràcia, Eulàlia; Bartolome, Rafael

    2014-05-01

    We present a new classification of geological domains at the Africa-Eurasia plate boundary off SW Iberia, together with a regional geodynamic reconstruction spanning from the Mesozoic extension to the Neogene-to-present-day convergence. It is based on seismic velocity and density models along two regional wide-angle seismic transects, one running NW-SE from the Horseshoe to the Seine abyssal plains, and the other running N-S from S Portugal to the Seine Abyssal Plain, combined with previously available information. The seismic velocity and density structure at the Seine Abyssal Plain and the internal Gulf of Cadiz indicates the presence of a highly heterogeneous oceanic crust, similar to that described in ultra-slow spreading centers, whereas in the Horseshoe and Tagus abyssal plains, the basement structure resembles that of exhumed mantle sections identified in the Northern Atlantic margin. The integration of all this new information allows defining the presence of three oceanic domains offshore SW Iberia: (1) the Seine Abyssal Plain domain, generated during the first stages of slow seafloor spreading in the NE Central Atlantic (Early Jurassic); (2) the Gulf of Cadiz domain, made of oceanic crust generated in the Alpine-Tethys spreading system between Iberia and Africa, which was coeval with the formation of the Seine Abyssal Plain domain and lasted up to the North Atlantic continental break-up (Late Jurassic); and (3) the Gorringe Bank domain, mainly made of rocks exhumed from the mantle with little synchronous magmatism, which formed during the first stages of North Atlantic opening. Our models suggest that the Seine Abyssal Plain and Gulf of Cadiz domains are separated by the Lineament South strike-slip fault, whereas the Gulf of Cadiz and Gorringe Bank domains appear to be limited by a deep thrust fault located at the center of the Horseshoe Abyssal Plain. The formation and evolution of these three domains during the Mesozoic is key to understand the sequence

  3. Ethnomycological studies of edible and medicinal mushrooms in the Mount Cameroon region (Cameroon, Africa).

    PubMed

    Kinge, Tonjock R; Tabi, Ebai M; Mih, Afui M; Enow, Egbe A; Njouonkou, L; Nji, T M

    2011-01-01

    Inhabitants of the Mount Cameroon region depend on the forest resources of the region for their livelihood, including the diverse use of macrofungi. With the increasing loss of forest due to exploitation and urbanization, they are liable to rapidly lose their indigenous knowledge of the forest resources, especially of mushrooms. An ethnomycological survey was conducted with the aim of documenting the indigenous knowledge of mushrooms as a prelude to conservation efforts. We also sought to assess the mycophilic and mycophobic tendencies of the inhabitants. It was revealed that traditionally, mushrooms were used as food, medicine, for mythological purposes, for aesthetics, and some poisonous species were also recorded. At least 15 different species were identified to be edible among the Bakweri people. Species used for ethnomedicine among the Bakweris belonged to several genera, including Termitomyces, Auricularia, Agaricus, Daldinia, Dictyophora, Pleurotus, Russula, Trametes, Chlorophyllum, and Ganoderma. Mushrooms were used as love charms, for dispelling evil spirits, and as part of cultural festivals.

  4. Labour migration and regional economic co-operation and integration in Africa.

    PubMed

    Ndongko, W A

    1991-01-01

    The author examines the experience of various economic groupings of African countries with regard to unrestricted migration among member countries. After an introduction, Section II "examines the nature of labour mobility (migration) during the colonial period. Section III is devoted to an analysis of the provisions for free labour movement/mobility within some African regional economic groupings. The nature and pattern of labour migration is looked at in section IV. In section V, the effects or impact of labour migration on national and regional economies are examined. Section VI attempts an analysis of the socio-economic problems which arise from labour mobility. In section VII, some substantial issues are examined. The final section attempts to formulate some policy recommendations."

  5. Surface Wave Analysis of Regional Earthquakes in the Eastern Rift System (Africa)

    NASA Astrophysics Data System (ADS)

    Oliva, S. J. C.; Guidarelli, M.; Ebinger, C. J.; Roecker, S. W.; Tiberi, C.

    2015-12-01

    The Northern Tanzania Divergence (NTD), the youngest part of the East African Rift System, presents the opportunity to obtain insights about the birth and early stages of rifting before it progresses to mature rifting and seafloor spreading. This region is particularly interesting because the Eastern rift splits into three arms in this area and develops in a region of thick and cold lithosphere, amid the Archaean Tanzanian craton and the Proterozoic orogenic belt (the Masai block). We analyzed about two thousand seismic events recorded by the 39 broadband stations of the CRAFTI network during its two-year deployment in the NTD area in 2013 to 2014. We present the results of surface wave tomographic inversion obtained from fundamental-mode Rayleigh waves for short periods (between 4 to 14 seconds). Group velocity dispersion curves obtained via multiple filter analysis are path-averaged and inverted to produce 0.1º x 0.1º nodal grid tomographic maps for discrete periods using a 2D generalization of the Backus and Gilbert method. To quantify our results in terms of S-wave velocity structure the average group velocity dispersion curves are then inverted, using a linearized least-squares inversion scheme, in order to obtain the shear wave velocity structure for the upper 20 km of the crust. Low velocity anomalies are observed in the region 50 km south of Lake Natron, as well as in the area of the Ngorongoro crater. The implications of our results for the local tectonics and the development of the rifting system will be discussed in light of the growing geophysical database from this region.

  6. The exodus of health professionals from sub-Saharan Africa: balancing human rights and societal needs in the twenty-first century.

    PubMed

    Ogilvie, Linda; Mill, Judy E; Astle, Barbara; Fanning, Anne; Opare, Mary

    2007-06-01

    Increased international migration of health professionals is weakening healthcare systems in low-income countries, particularly those in sub-Saharan Africa. The migration of nurses, physicians and other health professionals from countries in sub-Saharan Africa poses a major threat to the achievement of health equity in this region. As nurses form the backbone of healthcare systems in many of the affected countries, it is the accelerating migration of nurses that will be most critical over the next few years. In this paper we present a comprehensive analysis of the literature and argue that, from a human rights perspective, there are competing rights in the international migration of health professionals: the right to leave one's country to seek a better life; the right to health of populations in the source and destination countries; labour rights; the right to education; and the right to non-discrimination and equality. Creative policy approaches are required to balance these rights and to ensure that the individual rights of health professionals do not compromise the societal right to health.

  7. The Role of Deep Convection and Low-Level Jets Forcing Dust Emissions in West Africa: A High-Resolution Regional Dust Modelling Study

    NASA Astrophysics Data System (ADS)

    Heinold, B.; Knippertz, P.; Fiedler, S.; Marsham, J. H.; Tegen, I.

    2012-04-01

    West Africa is the world's most important source of atmospheric mineral dust, which impacts weather and climate through its contribution to the direct and indirect aerosol effects. Mineral dust also has an impact on the biogeochemical and hydrological cycle, and affects human health and air quality. Quantitative estimates of the various effects require an adequate representation of modelled peak-wind generating mechanisms that cause dust emissions. Daytime downward mixing of momentum from nocturnal low-level jets (LLJs) and convective cold pools (haboobs) have been identified as important meteorological drivers of dust emissions in the Sahel and Sahara. Previous work using 10-day continental-scale convection-permitting simulations of summertime West Africa, performed using the UK Met Office Unified model as part of the Cascade project, has shown that these processes dominate the modelled dust-generating winds, with haboobs being very poorly represented in models with parameterised deep convection. This previous work did not, however, model dust emission explicitly. As part of the "Desert Storms" project (funded by the European Research Council), we expand on this work here using newly available 40-day Cascade runs with dust emissions calculated in an offline model driven with the modelled surface winds at 40, 12, 4 and 1.5-km horizontal grid-spacings (6 days only at 1.5 km). These calculations include different versions of dust emission parameterisations and soil surface properties, allowing separation of meteorological and land-surface effects. A major focus is on the statistical analysis of the diurnal cycle of wind speed and dust emission, for which the long simulation period provides a robust basis. The diurnal cycle gives insight into the role of different meteorological processes and is expected to affect the subsequent dust transport in the boundary layer. The high-resolution results show dust emission patterns in fascinating detail. For the first time it

  8. Performance of the CORDEX-Africa regional climate simulations in representing the hydrological cycle of the Niger River basin

    NASA Astrophysics Data System (ADS)

    Mascaro, Giuseppe; White, Dave D.; Westerhoff, Paul; Bliss, Nadya

    2015-12-01

    The water resources of the Niger River basin (NRB) in West Africa are crucial to support the socioeconomic development of nine countries. In this study, we compared and evaluated performances of simulations at 0.44° resolution of several regional climate models (RCMs) of the Coordinated Regional climate Downscaling Experiment (CORDEX) in reproducing the statistical properties of the hydrological cycle of the NRB in the current climate. To capture the large range of climatic zones in the region, analyses were conducted by spatially averaging the water balance components in four nested subbasins. Most RCMs overestimate (order of +10% to +400%, depending on model and subbasin) the mean annual difference between precipitation (P) and evaporation (E), whose observed value was assumed equal to the long-term discharge based on the mass conservation principle. This is due to a tendency to simulate larger mean annual P and a weak hydrological cycle in the E channel. Some exceptions appear in the humid most-upstream subbasin, where a few RCMs underestimate P. Overall, the representation of the water balance is mostly sensitive to the parameterized land surface and atmospheric processes of the nested RCMs, with less influence of the driving general circulation model. This finding is supported by further analyses on seasonal cycle and spatial variability of the water balance components and on model performances in reproducing observed climatology. Results of this work should be considered when RCMs are used directly or in impact studies to develop policies and plan investments aimed at ensuring water sustainability in the NRB.

  9. South Africa

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This true-color image of South Africa was acquired on May 14, 2000, by NASA's Moderate-resolution Imaging Spectroradiometer, or MODIS. The image was produced using a combination of the sensor's 250-m and 500-m resolution visible wavelength bands. As part of the opening ceremony to begin the joint U.S.-South Africa SAFARI Field Experiment, NASA presented print copies of this image as GIFts to Dr. Ben Ngubane, Minister of Arts, Science and Technology, and Honorable Advocate Ngoaka Ramathlodi, Premier of the Northern Province, South Africa. The area shown in this image encompasses seven capital cities and a number of the region's distinctive geological features can be seen clearly. Toward the northern (top) central part of the image, the browns and tans comprise the Kalahari Desert of southern Botswana. The Tropic of Capricorn runs right through the heart of the Kalahari and the Botswanan capital city of Gaborone sits on the Limpopo River, southeast of the Kalahari. Along the western coastline of the continent is the country of Namibia, where the Namib Desert is framed against the sea by the Kaokoveld Mountains. The Namibian capital of Windhoek is obscured by clouds. Looking closely in the center of the image, the Orange River can be seen running from east to west, demarcating the boundary between Namibia and South Africa. On the southwestern corner of the continent is the hook-like Cape of Good Hope peninsula and Cape Town, the parliamentary capital of South Africa. Running west to east away from Cape Town are the Great Karroo Mountains. The shadow in this image conveys a sense of the very steep grade of the cliffs along the southern coast of South Africa. Port Elizabeth sits on the southeasternmost point of South Africa, and a large phytoplankton bloom can be seen in the water about 100 miles east of there. Moving northward along the east coast, the Drakensberg Mountains are visible. The two small nations of Lesotho and Swaziland are in this region, completely

  10. Spatiotemporal analysis of droughts using self-calibrating Palmer's Drought Severity Index in the central region of South Africa

    NASA Astrophysics Data System (ADS)

    Edossa, Desalegn C.; Woyessa, Yali E.; Welderufael, Worku A.

    2016-11-01

    The loss of life and property from drought events has forced society to focus on the development of reliable early warning systems which may enable farmers and other stakeholders to correctly and timely adapt to the expected impacts of climatic hazard. However, a scientific approach to a reliable early warning system for a region requires, among others, characterisation of drought events in the region in terms of duration, magnitude, intensity and frequency using standard drought indices. Therefore, the objective of this study was to identify and characterise drought events in the Modder River basin, central region of South Africa, using a self-calibrated Palmer's Drought Severity Index (sc-PDSI). Attempts were also made to establish a relationship between meteorological and hydrological drought events in the region. During the period of analysis, the total number of drought episodes identified in the study area ranged between eight and sixteen. It was found that the most severe drought episodes occurred during the period 1992-1995 followed by the period 1982-1987. Results of analysis of seasonal drought events in one of the quaternary catchments (C52A) revealed that peak drought events during the three summer months (November, December and January) occurred in the area in 1993. However, in terms of event magnitude and intensity, the worst drought events were recorded during the period December 1982-July 1987, followed by the event that ensued during December 1989-September 1995. Results of analysis of decadal variation of drought events showed that the number of extreme and moderate drought events recorded in the catchment showed statistically significant increasing trends during the five decades at 5 % significance level. Moreover, spectral analysis of sc-PDSI time series in the region identified periodicities in the time series ranging from 6 years (C52E) to 16 years (C52K). In terms of the spatial extent of extreme drought events, the maximum areal coverage (91

  11. GROUND TRUTH, MAGNITUDE CALIBRATION AND REGIONAL PHASE PROPAGATION AND DETECTION IN THE MIDDLE EAST AND HORN OF AFRICA

    SciTech Connect

    Nyblade, A; Adams, A; Brazier, R; Park, Y; Rodgers, A

    2006-07-10

    In this project, we are exploiting unique and open source seismic data sets to improve seismic monitoring across the Middle East (including the Iranian Plateau, Zagros Mountains, Arabian Peninsula, Turkish Plateau, Gulf of Aqaba, Dead Sea Rift) and the Horn of Africa (including the northern part of the East African Rift, Afar Depression, southern Red Sea and Gulf of Aden). The data sets are being used to perform three related tasks. (1) We are determining moment tensors, moment magnitudes and source depths for regional events in the magnitude 3.0 to 6.0 range. (2) These events are being used to characterize high-frequency (0.5-16 Hz) regional phase attenuation and detection thresholds, especially from events in Iran recorded at stations across the Arabian Peninsula. (3) We are collecting location ground truth at GT5 (local) and GT20 (regional) levels for seismic events with M > 2.5, including source geometry information and source depths. In the first phase of this project, seismograms from earthquakes in the Zagros Mountains recorded at regional distances have been inverted for moment tensors, and source depths for the earthquakes have been determined via waveform matching. Early studies of the distribution of seismicity in the Zagros region found evidence for earthquakes in the upper mantle. But subsequent relocations of teleseismic earthquakes suggest that source depths are generally much shallower, lying mainly within the upper crust. Nine events with magnitudes between 5 and 6 have been studied so far. Source depths for six of the events are within the upper crust, and three are located within the lower crust. The uncertainty in the source depths of the lower crustal events allows for the possibility that some of them may have even nucleated within the upper mantle. Eight events have thrust mechanisms and one has a strike-slip mechanism. We also report estimates of three-dimensional P- and S-wave velocity structure of the upper mantle beneath the Arabian

  12. Staphylococcus aureus complex from animals and humans in three remote African regions.

    PubMed

    Schaumburg, Frieder; Pauly, Maude; Anoh, Etile; Mossoun, Arsene; Wiersma, Lidewij; Schubert, Grit; Flammen, Arnaud; Alabi, Abraham S; Muyembe-Tamfum, Jean-Jacques; Grobusch, Martin P; Karhemere, Stomy; Akoua-Koffi, Chantal; Couacy-Hymann, Emmanuel; Kremsner, Peter G; Mellmann, Alexander; Becker, Karsten; Leendertz, Fabian H; Peters, Georg

    2015-04-01

    Staphylococcus schweitzeri has been recently considered to be a highly divergent Staphylococcus aureus clade and usually colonises nonhuman primates and bats in sub-Saharan Africa. Its transmissibility to humans remains unclear. We therefore investigated the transmission of S. aureus and S. schweitzeri among humans, domestic animals, and wildlife in three remote African regions. A cross-sectional study on nasal and pharyngeal colonisation in humans (n = 1288) and animals (n = 698) was performed in Côte d'Ivoire, Gabon, and Democratic Republic of Congo (DR Congo). Isolates were subjected to spa typing and multilocus sequence typing. Antimicrobial susceptibility and selected virulence factors were tested. S. schweitzeri was found in monkeys from all study sites but no transmission to humans was evident, despite frequent contact of humans with wildlife. In contrast, human-associated S. aureus sequence types (ST1, ST6, ST15) were detected in domestic animals and nonhuman primates, pointing toward a human-to-monkey transmission in the wild. The proportion of methicillin-resistant S. aureus (MRSA) among all S. aureus was 0% (Gabon), 1.7% (DR Congo), and 5.3% (Côte d'Ivoire). The majority of MRSA isolates belonged to the African clone ST88. In conclusion, we did not find any evidence for a transmission of S. schweitzeri from animals to humans. However, such a transmission might remain possible due to the close phylogenetic relation of humans and nonhuman primates. The ST88-MRSA clone was widespread in Côte d'Ivoire but not in Gabon and DR Congo.

  13. Cholera outbreaks in Africa.

    PubMed

    Mengel, Martin A; Delrieu, Isabelle; Heyerdahl, Leonard; Gessner, Bradford D

    2014-01-01

    During the current seventh cholera pandemic, Africa bore the major brunt of global disease burden. More than 40 years after its resurgence in Africa in 1970, cholera remains a grave public health problem, characterized by large disease burden, frequent outbreaks, persistent endemicity, and high CFRs, particularly in the region of the central African Great Lakes which might act as reservoirs for cholera. There, cases occur year round with a rise in incidence during the rainy season. Elsewhere in sub-Saharan Africa, cholera occurs mostly in outbreaks of varying size with a constant threat of widespread epidemics. Between 1970 and 2011, African countries reported 3,221,050 suspected cholera cases to the World Health Organization, representing 46 % of all cases reported globally. Excluding the Haitian epidemic, sub-Saharan Africa accounted for 86 % of reported cases and 99 % of deaths worldwide in 2011. The number of cholera cases is possibly much higher than what is reported to the WHO due to the variation in modalities, completeness, and case definition of national cholera data. One source on country specific incidence rates for Africa, adjusting for underreporting, estimates 1,341,080 cases and 160,930 deaths (52.6 % of 2,548,227 estimated cases and 79.6 % of 209,216 estimated deaths worldwide). Another estimates 1,411,453 cases and 53,632 deaths per year, respectively (50 % of 2,836,669 estimated cases and 58.6 % of 91,490 estimated deaths worldwide). Within Africa, half of all cases between 1970 and 2011 were notified from only seven countries: Angola, Democratic Republic of the Congo, Mozambique, Nigeria, Somalia, Tanzania, and South Africa. In contrast to a global trend of decreasing case fatality ratios (CFRs), CFRs have remained stable in Africa at approximately 2 %. Early propagation of cholera outbreaks depends largely on the extent of individual bacterial shedding, host and organism characteristics, the likelihood of people coming into contact with

  14. The Impact of Regional Climate Change on Malaria Risk due to Greenhouse Forcing and Land-Use Changes in Tropical Africa

    PubMed Central

    Fink, Andreas H.; Morse, Andrew P.; Paeth, Heiko

    2011-01-01

    Background: Climate change will probably alter the spread and transmission intensity of malaria in Africa. Objectives: In this study, we assessed potential changes in the malaria transmission via an integrated weather–disease model. Methods: We simulated mosquito biting rates using the Liverpool Malaria Model (LMM). The input data for the LMM were bias-corrected temperature and precipitation data from the regional model (REMO) on a 0.5° latitude–longitude grid. A Plasmodium falciparum infection model expands the LMM simulations to incorporate information on the infection rate among children. Malaria projections were carried out with this integrated weather–disease model for 2001 to 2050 according to two climate scenarios that include the effect of anthropogenic land-use and land-cover changes on climate. Results: Model-based estimates for the present climate (1960 to 2000) are consistent with observed data for the spread of malaria in Africa. In the model domain, the regions where malaria is epidemic are located in the Sahel as well as in various highland territories. A decreased spread of malaria over most parts of tropical Africa is projected because of simulated increased surface temperatures and a significant reduction in annual rainfall. However, the likelihood of malaria epidemics is projected to increase in the southern part of the Sahel. In most of East Africa, the intensity of malaria transmission is expected to increase. Projections indicate that highland areas that were formerly unsuitable for malaria will become epidemic, whereas in the lower-altitude regions of the East African highlands, epidemic risk will decrease. Conclusions: We project that climate changes driven by greenhouse-gas and land-use changes will significantly affect the spread of malaria in tropical Africa well before 2050. The geographic distribution of areas where malaria is epidemic might have to be significantly altered in the coming decades. PMID:21900078

  15. An overview of regional and local characteristics of aerosols in South Africa using satellite, ground, and modeling data

    NASA Astrophysics Data System (ADS)

    Hersey, S. P.; Garland, R. M.; Crosbie, E.; Shingler, T.; Sorooshian, A.; Piketh, S.; Burger, R.

    2014-09-01

    domestic burning influence, (2) urban and suburban residential sites with no domestic burning in the immediate vicinity, (3) industrial sites, and (4) one traffic site situated at a major freeway interchange. PM10 concentrations in township areas are 56% higher than in developed residential areas and 78% higher than in industrial areas as an annual average, with PM10 in townships 63 and 136% higher than developed residential and industrial areas, respectively, in winter (June, July, August). Monthly PM10 and PM2.5 concentrations reach annual maxima during winter at all sites except in industrial areas. At industrial sites, maxima in PM10 and PM2.5 tend to occur during summer (December-February), when photochemical generation of secondary aerosol is expected and when deep and unstable boundary layers allow high stack emissions (emitted above the boundary layer during winter) to reach the ground in close proximity to point sources. Diurnal profiles of PM10 and PM2.5 display maxima during morning (06:00-09:00 LT) and evening (17:00-22:00 LT) at nearly every site - especially during winter - and underscore the importance of domestic burning as a major source of primary particles. Multi-year averages indicate that evening maxima at some township sites average in excess of 400 μg m-3. These results from the urban/industrial Gauteng area quantitatively confirm previous studies suggesting that the lowest-income populations of South Africa experience the poorest air quality, and demonstrate that domestic burning results in frequent exposure to high concentrations of particulate pollution in the region comprising the cities of Johannesburg and Tshwane. While remotely-sensed data are frequently used as a proxy for ground air quality, we report poor correlations between PM concentrations and satellite parameters and suggest that this practice is not appropriate in metropolitan South Africa. Disagreement between satellite and ground data may be attributed to a number of factors: (1

  16. Impact of HIV/AIDS on Gross Domestic Product (GDP) in the WHO Africa Region.

    PubMed

    Kirigia, Joses M; Sambo, Luis G; Okorosobo, Tuoyo; Mwabu, Germano M

    2002-01-01

    HIV/AIDS is hypothesized to have substantive negative impact on health status and economic development of individuals, households, communities and nations. The objective of this study was to estimate the burden of HIV/AIDS on GDP in the WHO African Region using a production function approach. The economic burden analysis was done using a double-log econometric model and a cross-sectional data on 45 to 46 countries in the WHO African Region. The data were obtained from WHO, UNAIDS, ECA, UNDP and the World Bank publications. The coefficient for Capital (K), Education (EN), Export (X) and Imports (M) were found to be statistically significant determinants of per capita Gross Domestic Product (GDP) at 5% level of significance (using a one-sided t-distribution test). Unfortunately, HIV/AIDS morbidity (V) and HIV/AIDS deaths (VD), at the same level of significance, were found to have statistically insignificant impact on GDP. However, the coefficients of these variables had negative signs as expected. In all African countries, there is need for more detailed research on the total economic cost of HIV/AIDS (probably estimated using micro-level costing and willingness-to-pay methods) and for economic evaluations of treatment, prevention and promotion programmes.

  17. Functional Traits in Parallel Evolutionary Radiations and Trait-Environment Associations in the Cape Floristic Region of South Africa.

    PubMed

    Mitchell, Nora; Moore, Timothy E; Mollmann, Hayley Kilroy; Carlson, Jane E; Mocko, Kerri; Martinez-Cabrera, Hugo; Adams, Christopher; Silander, John A; Jones, Cynthia S; Schlichting, Carl D; Holsinger, Kent E

    2015-04-01

    Evolutionary radiations with extreme levels of diversity present a unique opportunity to study the role of the environment in plant evolution. If environmental adaptation played an important role in such radiations, we expect to find associations between functional traits and key climatic variables. Similar trait-environment associations across clades may reflect common responses, while contradictory associations may suggest lineage-specific adaptations. Here, we explore trait-environment relationships in two evolutionary radiations in the fynbos biome of the highly biodiverse Cape Floristic Region (CFR) of South Africa. Protea and Pelargonium are morphologically and evolutionarily diverse genera that typify the CFR yet are substantially different in growth form and morphology. Our analytical approach employs a Bayesian multiple-response generalized linear mixed-effects model, taking into account covariation among traits and controlling for phylogenetic relationships. Of the pairwise trait-environment associations tested, 6 out of 24 were in the same direction and 2 out of 24 were in opposite directions, with the latter apparently reflecting alternative life-history strategies. These findings demonstrate that trait diversity within two plant lineages may reflect both parallel and idiosyncratic responses to the environment, rather than all taxa conforming to a global-scale pattern. Such insights are essential for understanding how trait-environment associations arise and how they influence species diversification.

  18. Polybrominated diphenyl ethers and alternative flame retardants in air and precipitation samples from the northern Lake Victoria region, East Africa.

    PubMed

    Arinaitwe, Kenneth; Muir, Derek C G; Kiremire, Bernard T; Fellin, Phil; Li, Henrik; Teixeira, Camilla

    2014-01-01

    High volume air and precipitation samples were collected close to the shore of Lake Victoria at Entebbe, Uganda, between October 2008 and July 2010 inclusive. Polybrominated diphenyl ethers (PBDEs) and alternative flame retardants (AFRs) were analyzed by GC-MS. BDEs 47, 99, and 209 were the predominant PBDEs with mean concentrations (in air) of 9.84, 4.38, 8.27 pg m(-3) and mean fluxes in precipitation of 3.40, 6.23, and 7.82 ng m(-2) sample(-1), respectively. 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), and hexabromocyclododecane (HBCDD), anti- and syn-Dechlorane plus were detected at levels comparable with those of PBDEs. Both PBDEs and AFRs in air generally increased from 2008 to 2010. Elevated PBDE concentrations in air were associated with slow moving low altitude air masses from the region immediately adjacent to the lake, while low concentrations were mostly associated with fast moving westerly and southwesterly air masses. Analysis of the octa- and nona-BDE profiles suggested photolysis and pyrolytic debromination of BDE-209 in the air samples. The highly halogenated and most abundant PBDEs and AFRs in air also predominated in precipitation samples. This is the first study to report flame retardants in high volume air samples and precipitation in Equatorial Africa.

  19. Human rights violations and smoking status among South African adults enrolled in the South Africa Stress and Health (SASH) study.

    PubMed

    Dutra, Lauren M; Williams, David R; Gupta, Jhumka; Kawachi, Ichiro; Okechukwu, Cassandra A

    2014-03-01

    Despite South Africa's history of violent political conflict, and the link between stressful experiences and smoking in the literature, no public health study has examined South Africans' experiences of human rights violations and smoking. Using data from participants in the nationally representative cross-sectional South Africa Stress and Health study (SASH), this analysis examined the association between respondent smoking status and both human rights violations experienced by the respondent and violations experienced by the respondents' close friends and family members. SAS-Callable SUDAAN was used to construct separate log-binomial models by political affiliation during apartheid (government or liberation supporters). In comparison to those who reported no violations, in adjusted analyses, government supporters who reported violations of themselves but not others (RR = 1.76, 95% CI: 1.25-2.46) had a significantly higher smoking prevalence. In comparison to liberation supporters who reported no violations, those who reported violations of self only (RR = 1.56, 95%CI: 1.07-2.29), close others only (RR = 1.97, 95%CI: 1.12-3.47), or violations of self and close others due to close others' political beliefs and the respondent's political beliefs (RR = 2.86, 95%CI: 1.70-4.82) had a significantly higher prevalence of smoking. The results of this analysis suggest that a relationship may exist between human rights violations and smoking among South Africa adults. Future research should use longitudinal data to assess causality, test the generalizability of these findings, and consider how to apply these findings to smoking cessation interventions.

  20. A review of screening strategies for cervical cancer in human immunodeficiency virus-positive women in sub-Saharan Africa

    PubMed Central

    Viviano, Manuela; DeBeaudrap, Pierre; Tebeu, Pierre-Marie; Fouogue, Jovanny T; Vassilakos, Pierre; Petignat, Patrick

    2017-01-01

    Cervical cancer (CC) is a leading cause of cancer-related death and a major public health issue in sub-Saharan Africa. This heavy burden parallels that of the human immunodeficiency virus (HIV) infection, which increases the risk of developing CC. Despite the progressive reduction of HIV prevalence in the past decade, the CC incidence and mortality rates in sub-Saharan Africa remain high. The heterogeneity of the distribution of the two diseases in the African continent, together with the different availability of human and material resources, stands in the way of finding an appropriate screening strategy. The lack of high-quality evidence on the prevention of CC for HIV-positive women, which is necessary for the implementation of efficient screening and treatment strategies, results in the absence of a clearly defined program, which is responsible for the low screening uptake and high mortality rates in sub-Saharan Africa. By taking advantage of the HIV-positive women’s frequent access to health facilities, one way to increase the CC screening coverage rates would be by providing integrated HIV and screening services within the same infrastructure. With the increasing availability of cost-effective methods, screening is becoming more and more available to women who have limited access to health care. Moreover, the introduction of point-of-care technologies for human papillomavirus testing and the subsequent implementation of screen-and-treat strategies, by reducing the number of clinical appointments and, in the long term, the loss to follow-up rates, open up new opportunities for all women, regardless of their HIV status. The purpose of this review is to provide an insight into the different screening practices for CC in order to help define one that is adapted to the resources and necessities of HIV-positive women living in middle-to-low income countries. PMID:28203108

  1. Roles of Spatial Scale and Rarity on the Relationship between Butterfly Species Richness and Human Density in South Africa.

    PubMed

    Mecenero, Silvia; Altwegg, Res; Colville, Jonathan F; Beale, Colin M

    2015-01-01

    Wildlife and humans tend to prefer the same productive environments, yet high human densities often lead to reduced biodiversity. Species richness is often positively correlated with human population density at broad scales, but this correlation could also be caused by unequal sampling effort leading to higher species tallies in areas of dense human activity. We examined the relationships between butterfly species richness and human population density at five spatial resolutions ranging from 2' to 60' across South Africa. We used atlas-type data and spatial interpolation techniques aimed at reducing the effect of unequal spatial sampling. Our results confirm the general positive correlation between total species richness and human population density. Contrary to our expectations, the strength of this positive correlation did not weaken at finer spatial resolutions. The patterns observed using total species richness were driven mostly by common species. The richness of threatened and restricted range species was not correlated to human population density. None of the correlations we examined were particularly strong, with much unexplained variance remaining, suggesting that the overlap between butterflies and humans is not strong compared to other factors not accounted for in our analyses. Special consideration needs to be made regarding conservation goals and variables used when investigating the overlap between species and humans for biodiversity conservation.

  2. Roles of Spatial Scale and Rarity on the Relationship between Butterfly Species Richness and Human Density in South Africa

    PubMed Central

    Mecenero, Silvia; Altwegg, Res; Colville, Jonathan F.; Beale, Colin M.

    2015-01-01

    Wildlife and humans tend to prefer the same productive environments, yet high human densities often lead to reduced biodiversity. Species richness is often positively correlated with human population density at broad scales, but this correlation could also be caused by unequal sampling effort leading to higher species tallies in areas of dense human activity. We examined the relationships between butterfly species richness and human population density at five spatial resolutions ranging from 2' to 60' across South Africa. We used atlas-type data and spatial interpolation techniques aimed at reducing the effect of unequal spatial sampling. Our results confirm the general positive correlation between total species richness and human population density. Contrary to our expectations, the strength of this positive correlation did not weaken at finer spatial resolutions. The patterns observed using total species richness were driven mostly by common species. The richness of threatened and restricted range species was not correlated to human population density. None of the correlations we examined were particularly strong, with much unexplained variance remaining, suggesting that the overlap between butterflies and humans is not strong compared to other factors not accounted for in our analyses. Special consideration needs to be made regarding conservation goals and variables used when investigating the overlap between species and humans for biodiversity conservation. PMID:25915899

  3. Dermatophytosis in northern Africa.

    PubMed

    Nweze, E I; Eke, I

    2016-03-01

    Infections caused by dermatophytes are a global problem and a major public health burden in the world today. In Africa, especially in the northern geographical zone, dermatophytic infections are being reported at an alarming rate. This is mostly because of some local but unique cultural practices, socioeconomic and environmental conditions, lack of reliable diagnostic personnel and facilities and ineffective treatment. Interestingly, the pathogen spectrum and the clinical manifestation are most times different from what is seen in other continents. Several epidemiological studies have been performed on the incidence and aetiology of dermatophytoses in northern Africa. However, there is currently no review article with up-to-date information on the relevant findings reported so far in this region. This information is necessary for clinicians who treat dermatophytic infections all over the world since agents of dermatophytes are no longer restricted because of the rapid mobility of humans from one part of the world to another. Moreover, the epidemiology of dermatophytoses is known to change over time, thus requiring the update of information from time to time. A review of relevant studies published on dermatophytoses in northern Africa is presented. This covers all of old Sudan, Algeria, Egypt, Libya, Tunisia and Morocco.

  4. Structural analysis of the 5 prime flanking region of the. beta. -globin gene in African sickle cell anemia patients: Further evidence for three origins of the sickle cell mutation in Africa

    SciTech Connect

    Chebloune, Y.; Pagnier, J.; Trabuchet, G.; Faure, C.; Verdier, G.; Labie, D.; Nigon, V. )

    1988-06-01

    Haplotype analysis of the {beta}-globin gene cluster shows two regions of DNA characterized by nonrandom association of restriction site polymorphisms. These regions are separated by a variable segment containing the repeated sequences (ATTTT){sub n} and (AT){sub x}T{sub y}, which might be involved in recombinational events. Studies of haplotypes linked to the sickle cell gene in Africa provide strong argument for three origins of the mutation: Benin, Senegal, and the Central African Republic. The structure of the variable segment in the three African populations was studied by S1 nuclease mapping of genomic DNA, which allows a comparison of several samples. A 1080-base-pair DNA segment was sequenced for one sample from each population. S1 nuclease mapping confirmed the homogeneity of each population with regard to both (ATTTT){sub n} and (AT){sub x}T{sub y} repeats. The authors found three additional structures for (AT){sub x}T{sub y} correlating with the geographic origin of the patients. Ten other nucleotide positions, 5{prime} and 3{prime} to the (AT){sub x}T{sub y} copies, were found to be variable when compared to homologous sequences from human and monkey DNAs. These results allow us to propose an evolutionary scheme for the polymorphisms in the 5{prime} flanking region of the {beta}-globin gene. The results strongly support the hypothesis of three origins for the sickle mutation in Africa.

  5. Habitat type and nursery function for coastal marine fish species, with emphasis on the Eastern Cape region, South Africa

    NASA Astrophysics Data System (ADS)

    Whitfield, Alan K.; Pattrick, Paula

    2015-07-01

    A considerable amount of research has been undertaken to document and assess the nursery function of a variety of coastal habitats for marine fish species around the world. Most of these studies have focused on particular habitats and have generally been confined to a limited range of fish species associated with specific nursery areas. In this review we conduct a general assessment of the state of knowledge of coastal habitats in fulfilling the nursery-role concept for marine fishes, with particular emphasis on biotic and abiotic factors that influence nursery value. A primary aim was to synthesize information that can be used to drive sound conservation planning and provide a conceptual framework so that new marine protected areas (MPAs) incorporate the full range of nursery areas that are present within the coastal zone. We also use published data from a coastal section in the Eastern Cape Province, South Africa, to highlight the differential use of shallow aquatic habitats by a range of juvenile marine fish species within this region. Although the Eastern Cape case study does not assess the relative growth, food availability or predation in nursery and non-nursery areas within the coastal zone, it does document which habitats are important to the juveniles of dominant marine species within each area. These habitats, which range from intertidal pools, subtidal gulleys and surf zones to estuaries, do appear to perform a key role in the biological success of species assemblages, with the juveniles of particular marine fishes tending to favour specific nursery areas. According to a multivariate analysis of nursery habitat use within this region, marine species using estuaries tend to differ considerably from those using nearshore coastal waters, with a similar pattern likely to occur elsewhere in the world.

  6. Delineating geographical regions with networks of human interactions in an extensive set of countries.

    PubMed

    Sobolevsky, Stanislav; Szell, Michael; Campari, Riccardo; Couronné, Thomas; Smoreda, Zbigniew; Ratti, Carlo

    2013-01-01

    Large-scale networks of human interaction, in particular country-wide telephone call networks, can be used to redraw geographical maps by applying algorithms of topological community detection. The geographic projections of the emerging areas in a few recent studies on single regions have been suggested to share two distinct properties: first, they are cohesive, and second, they tend to closely follow socio-economic boundaries and are similar to existing political regions in size and number. Here we use an extended set of countries and clustering indices to quantify overlaps, providing ample additional evidence for these observations using phone data from countries of various scales across Europe, Asia, and Africa: France, the UK, Italy, Belgium, Portugal, Saudi Arabia, and Ivory Coast. In our analysis we use the known approach of partitioning country-wide networks, and an additional iterative partitioning of each of the first level communities into sub-communities, revealing that cohesiveness and matching of official regions can also be observed on a second level if spatial resolution of the data is high enough. The method has possible policy implications on the definition of the borderlines and sizes of administrative regions.

  7. Poverty and blindness in Africa.

    PubMed

    Naidoo, Kovin

    2007-11-01

    Africa carries a disproportionate responsibility in terms of blindness and visual impairment. With approximately 10 per cent of the world's population, Africa has 19 per cent of the world's blindness. It is no surprise that this reality also mirrors the situation in terms of the burden of world poverty. There is an increasing recognition of the need to highlight the link between poverty, development and health care. Blindness, disabling visual impairment and the overall lack of eye-care services are too often the result of social, economic and developmental challenges of the developing world. The state of eye care in Africa stands in alarming contrast to that in the rest of the world. Poor practitioner-to-patient ratios, absence of eye-care personnel, inadequate facilities, poor state funding and a lack of educational programs are the hallmarks of eye care in Africa, with preventable and treatable conditions being the leading cause of blindness. Eye diseases causing preventable blindness are often the result of a combination of factors such as poverty, lack of education and inadequate health-care services. The challenge that Vision 2020 has set itself in Africa is enormous. Africa is not a homogenous entity, the inter- and intra-country differences in economic development, prevalence of disease, delivery infrastructure and human resources amplify the challenges of meeting eye-care needs. The successful implementation of Vision 2020 programs will be hindered without the development of a comprehensive, co-ordinated strategy that is cognisant of the differences that exist and the need for comprehensive solutions that are rooted in the economic and political realities of the continent as well as the individual countries and regions within countries. This strategy should recognise the need for economic growth that results in greater state funded eye-care services that focus on health promotion to ensure the prevention of eye disease, the development of eye clinics in

  8. Linguistic Human Rights in Africa: Challenges and Prospects for Indigenous Languages in Kenya

    ERIC Educational Resources Information Center

    Musau, Paul M.

    2003-01-01

    With reference to Kenya, the paper shows that although linguistic rights have been eloquently articulated in various charters and declarations, their implementation has been problematic. In Africa this has led to an imbalance of status between the former colonial languages and the indigenous ones. This imbalance is evident in the educational…

  9. Education and Language: A Human Right for Sustainable Development in Africa

    ERIC Educational Resources Information Center

    Babaci-Wilhite, Zehlia; Geo-JaJa, Macleans A.; Lou, Shizhou

    2012-01-01

    Pre-colonial Africa was neither an educationally nor a technologically unsophisticated continent. While education was an integral part of the culture, issues of language identification and standardisation which are subject to contentious debate today were insignificant. Children learned community knowledge and history by asking questions instead…

  10. Simian foamy virus in non-human primates and cross-species transmission to humans in Gabon: an emerging zoonotic disease in central Africa?

    PubMed

    Mouinga-Ondémé, Augustin; Kazanji, Mirdad

    2013-06-19

    It is now known that all human retroviruses have a non-human primate counterpart. It has been reported that the presence of these retroviruses in humans is the result of interspecies transmission. Several authors have described the passage of a simian retrovirus, simian foamy virus (SFV), from primates to humans. To better understand this retroviral "zoonosis" in natural settings, we evaluated the presence of SFV in both captive and wild non-human primates and in humans at high risk, such as hunters and people bitten by a non-human primate, in Gabon, central Africa. A high prevalence of SFV was found in blood samples from non-human primates and in bush meat collected across the country. Mandrills were found to be highly infected with two distinct strains of SFV, depending on their geographical location. Furthermore, samples collected from hunters and non-human primate laboratory workers showed clear, extensive cross-species transmission of SFV. People who had been bitten by mandrills, gorillas and chimpanzees had persistent SFV infection with low genetic drift. Thus, SFV is presumed to be transmitted from non-human primates mainly through severe bites, involving contact between infected saliva and blood. In this review, we summarize and discuss our five-year observations on the prevalence and dissemination of SFV in humans and non-human primates in Gabon.

  11. The Hidden Costs of a Free Caesarean Section Policy in West Africa (Kayes Region, Mali).

    PubMed

    Ravit, Marion; Philibert, Aline; Tourigny, Caroline; Traore, Mamadou; Coulibaly, Aliou; Dumont, Alexandre; Fournier, Pierre

    2015-08-01

    The fee exemption policy for EmONC in Mali aims to lower the financial barrier to care. The objective of the study was to evaluate the direct and indirect expenses associated with caesarean interventions performed in EmONC and the factors associated with these expenses. Data sampling followed the case control approach used in the large project (deceased and near-miss women). Our sample consisted of a total of 190 women who underwent caesarean interventions. Data were collected from the health workers and with a social approach by administering questionnaires to the persons who accompanied the woman. Household socioeconomic status was assessed using a wealth index constructed with a principal component analysis. The factors significantly associated with expenses were determined using multivariate linear regression analyses. Women in the Kayes region spent on average 77,017 FCFA (163 USD) for a caesarean episode in EmONC, of which 70 % was for treatment. Despite the caesarean fee exemption, 91 % of the women still paid for their treatment. The largest treatment-related direct expenses were for prescriptions, transfusion, antibiotics, and antihypertensive medication. Near-misses, women who presented a hemorrhage or an infection, and/or women living in rural areas spent significantly more than the others. Although abolishing fees of EmONC in Mali plays an important role in reducing maternal death by increasing access to caesarean sections, this paper shows that the fee policy did not benefit to all women. There are still barriers to EmONC access for women of the lowest socio-economic group. These included direct expenses for drugs prescription, treatment and indirect expenses for transport and food.

  12. Rhizobia Indigenous to the Okavango Region in Sub-Saharan Africa: Diversity, Adaptations, and Host Specificity

    PubMed Central

    Grönemeyer, Jann L.; Kulkarni, Ajinkya; Berkelmann, Dirk; Hurek, Thomas

    2014-01-01

    The rhizobial community indigenous to the Okavango region has not yet been characterized. The isolation of indigenous rhizobia can provide a basis for the formulation of a rhizobial inoculant. Moreover, their identification and characterization contribute to the general understanding of species distribution and ecology. Isolates were obtained from nodules of local varieties of the pulses cowpea, Bambara groundnut, peanut, hyacinth bean, and common bean. Ninety-one of them were identified by BOX repetitive element PCR (BOX-PCR) and sequence analyses of the 16S-23S rRNA internally transcribed spacer (ITS) and the recA, glnII, rpoB, and nifH genes. A striking geographical distribution was observed. Bradyrhizobium pachyrhizi dominated at sampling sites in Angola which were characterized by acid soils and a semihumid climate. Isolates from the semiarid sampling sites in Namibia were more diverse, with most of them being related to Bradyrhizobium yuanmingense and Bradyrhizobium daqingense. Host plant specificity was observed only for hyacinth bean, which was nodulated by rhizobia presumably representing yet-undescribed species. Furthermore, the isolates were characterized with respect to their adaptation to high temperatures, drought, and local host plants. The adaptation experiments revealed that the Namibian isolates shared an exceptionally high temperature tolerance, but none of the isolates showed considerable adaptation to drought. Moreover, the isolates' performance on different local hosts showed variable results, with most Namibian isolates inducing better nodulation on peanut and hyacinth bean than the Angolan strains. The local predominance of distinct genotypes implies that indigenous strains may exhibit a better performance in inoculant formulations. PMID:25239908

  13. Rhizobia Indigenous to the Okavango Region in Sub-Saharan Africa: Diversity, Adaptations, and Host Specificity.

    PubMed

    Grönemeyer, Jann L; Kulkarni, Ajinkya; Berkelmann, Dirk; Hurek, Thomas; Reinhold-Hurek, Barbara

    2014-12-01

    The rhizobial community indigenous to the Okavango region has not yet been characterized. The isolation of indigenous rhizobia can provide a basis for the formulation of a rhizobial inoculant. Moreover, their identification and characterization contribute to the general understanding of species distribution and ecology. Isolates were obtained from nodules of local varieties of the pulses cowpea, Bambara groundnut, peanut, hyacinth bean, and common bean. Ninety-one of them were identified by BOX repetitive element PCR (BOX-PCR) and sequence analyses of the 16S-23S rRNA internally transcribed spacer (ITS) and the recA, glnII, rpoB, and nifH genes. A striking geographical distribution was observed. Bradyrhizobium pachyrhizi dominated at sampling sites in Angola which were characterized by acid soils and a semihumid climate. Isolates from the semiarid sampling sites in Namibia were more diverse, with most of them being related to Bradyrhizobium yuanmingense and Bradyrhizobium daqingense. Host plant specificity was observed only for hyacinth bean, which was nodulated by rhizobia presumably representing yet-undescribed species. Furthermore, the isolates were characterized with respect to their adaptation to high temperatures, drought, and local host plants. The adaptation experiments revealed that the Namibian isolates shared an exceptionally high temperature tolerance, but none of the isolates showed considerable adaptation to drought. Moreover, the isolates' performance on different local hosts showed variable results, with most Namibian isolates inducing better nodulation on peanut and hyacinth bean than the Angolan strains. The local predominance of distinct genotypes implies that indigenous strains may exhibit a better performance in inoculant formulations.

  14. Molecular characterization of Wilms tumor from a resource-constrained region of sub-Saharan Africa

    PubMed Central

    Murphy, Andrew J.; Axt, Jason R.; de Caestecker, Christian; Pierce, Janene; Correa, Hernan; Seeley, Erin H.; Caprioli, Richard M.; Newton, Mark W.; de Caestecker, Mark P.; Lovvorn, Harold N.

    2012-01-01

    Sub-Saharan African children have an increased incidence of Wilms tumor (WT) and experience alarmingly poor outcomes. Although these outcomes are largely due to inadequate therapy, we hypothesized that WT from this region exhibit features of biologic aggressiveness that may warrant broader implementation of high-risk therapeutic protocols. We evaluated 15 Kenyan WT (KWT) for features of aggressive disease (blastemal predominance, Ki67/cellular proliferation) and treatment resistance (anaplasia, p53 immunopositivity). To explore additional biologic features of KWT, we determined the mutational status of the CTNNB1/β-catenin and WT1 genes and performed immunostaining for markers of Wnt pathway activation (β-catenin) and nephronic progenitor cell self-renewal (WT1, CITED1, SIX2). We characterized the proteome of KWT using imaging mass spectrometry (IMS). Results were compared to histology and age-matched North American WT (NAWT) controls. For KWT patients, blastemal predominance was noted in 53.3% and anaplasia in 13%. We detected increased loss to follow up (p=0.028), disease relapse (p=0.044), mortality (p=0.001), and nuclear unrest (p=0.001) in KWT patients compared to controls. KWT and NAWT showed similar Ki67/cellular proliferation. We detected an increased proportion of epithelial nuclear β-catenin in KWT (p=0.013). All 15 KWT were found to harbor wild-type β-catenin, and 1 contained a WT1 nonsense mutation. WT1 was detected by immunostaining in 100% of KWT, CITED1 in 80%, and SIX2 in 80%. IMS revealed a molecular signature unique to KWT that was distinct from NAWT. African WTs appear to express markers of adverse clinical behavior and treatment resistance and may require alternative therapies or implementation of high-risk treatment protocols. PMID:22437966

  15. Discovery of a new human T-cell lymphotropic virus (HTLV-3) in Central Africa.

    PubMed

    Calattini, Sara; Chevalier, Sébastien Alain; Duprez, Renan; Bassot, Sylviane; Froment, Alain; Mahieux, Renaud; Gessain, Antoine

    2005-05-09

    Human T-cell Leukemia virus type 1 (HTLV-1) and type 2 (HTLV-2) are pathogenic retroviruses that infect humans and cause severe hematological and neurological diseases. Both viruses have simian counterparts (STLV-1 and STLV-2). STLV-3 belongs to a third group of lymphotropic viruses which infect numerous African monkeys species. Among 240 Cameroonian plasma tested for the presence of HTLV-1 and/or HTLV-2 antibodies, 48 scored positive by immunofluorescence. Among those, 27 had indeterminate western-blot pattern. PCR amplification of pol and tax regions, using HTLV-1, -2 and STLV-3 highly conserved primers, demonstrated the presence of a new human retrovirus in one DNA sample. tax (180 bp) and pol (318 bp) phylogenetic analyses demonstrated the strong relationships between the novel human strain (Pyl43) and STLV-3 isolates from Cameroon. The virus, that we tentatively named HTLV-3, originated from a 62 years old Bakola Pygmy living in a remote settlement in the rain forest of Southern Cameroon. The plasma was reactive on MT2 cells but was negative on C19 cells. The HTLV 2.4 western-blot exhibited a strong reactivity to p19 and a faint one to MTA-1. On the INNO-LIA strip, it reacted faintly with the generic p19 (I/II), but strongly to the generic gp46 (I/II) and to the specific HTLV-2 gp46. The molecular relationships between Pyl43 and STLV-3 are thus not paralleled by the serological results, as most of the STLV-3 infected monkeys have an "HTLV-2 like" WB pattern. In the context of the multiple interspecies transmissions which occurred in the past, and led to the present-day distribution of the PTLV-1, it is thus very tempting to speculate that this newly discovered human retrovirus HTLV-3 might be widespread, at least in the African continent.

  16. Fire and Emission Characterization in the Northern Sub-Saharan Africa (NSSA) Region and their Potential Effects on the Regional Climate System

    NASA Astrophysics Data System (ADS)

    Ellison, L.; Ichoku, C. M.

    2013-12-01

    Northern Sub-Saharan Africa (NSSA) is known for its consistent vast amounts of seasonal biomass burning each year. These mostly anthropogenic slash-and-burn fires typically used for farming and grazing purposes contributes to a significant proportion of the total global emissions of particulate matter (PM). The consequences of such severe burning could potentially have a noticeable influence on local climate patterns, such as the frequent severe droughts over the past century or the drying of Lake Chad, through both direct and indirect causes. This research therefore focuses on: 1) characterizing the burning patterns and extent within NSSA, 2) accurately quantifying PM emissions that have a direct impact on climate, and 3) exploring potential indirect impacts of burning on climate through evaluation of correlations with various environmental and meteorological parameters. In this study, the NSSA region was first split into nine distinct sub-regions to better analyze the burning patters and climatological changes. The diurnal cycle of fire radiative power (FRP, a quantifiable way of measuring fire radiant heat output) within these different regions differ in amplitude and shape, though the basic shape is the same with months of maximum FRP being between November and January and with practically no fires during the rainy season. Corresponding changes in other climatological variables were studied against changes seen in FRP on a monthly scale, including precipitation, soil moisture, surface evaporation, evapotranspiration (ET), normalized difference vegetation index (NDVI) and aerosol optical depth (AOD). This study includes an analysis of the distinct change in FRP signal that occurred in 2006 for the middle of the NSSA region, which is the area with the highest concentration of fires. A decrease in maximum monthly FRP has been observed since 2006 in this region. Regional changes in PM emissions have also been observed since then, including a large region of

  17. Using remote sensing to create indicators of ecosystem variability for a semi-arid savanna watershed in the Kavango-Zambezi region of Southern Africa

    NASA Astrophysics Data System (ADS)

    Pricope, Narcisa Gabriela

    This dissertation addresses changes in land and resource availability occurring as a result of climate, water variability and changes in fire regimes in a semi-arid savanna region in Southern Africa. The research combines geospatial analyses of climatological and hydrologic data and various remotely-sensed datasets to create measures of ecosystem variability and adaptability to natural and anthropogenic changes in sensitive ecosystems. The study area is the Chobe River Basin (CRB), a watershed shared between Botswana and Namibia situated at the heart of one of the world.s largest transfrontier conservation areas, where different land-use management strategies and economic policies affect both the ecosystem and the livelihoods support system differentially. The southern African savanna is a highly variable environment and people have adapted to its harshness through the generations. However, in light of past and ongoing environmental changes, their ability to adapt may become threatened. By mapping and then analyzing the spatial and temporal variability of two important factors, namely flooding and fires, in conjunction with indices of vegetation health and productivity, the findings of this research can ultimately contribute to enhancing our understanding of local adaptation mechanisms to future environmental change. This is the first reconstruction of the spatial and temporal patterns of inundation for the last 25 years in the CRB, a transboundary basin with an unusual hydrologic regime and an important water resource for both human and wildlife populations. In the context of increasing temperatures, decreasing precipitation trends and increasing frequencies and intensities of El Nino episodes in southern Africa (Boko et al., 2007), I also investigated changes in fire incidences and marked shifts in fire seasonality both within and outside of protected areas of central Kavango Zambezi Transfrontier Conservation Area (KAZA TFCA). These changes are likely to have a

  18. Atmospheric chemistry over southern Africa

    NASA Astrophysics Data System (ADS)

    Gatebe, Charles K.; Levy, Robert C.; Thompson, Anne M.

    2012-03-01

    Changing Chemistry in a Changing Climate: Human and Natural Impacts Over Southern Africa (C4-SAR); Midrand, South Africa, 31 May to 3 June 2011 During the southern African dry season, regional haze from mixed industrial pollution, biomass burning aerosol and gases from domestic and grassland fires, and biogenic sources from plants and soils is worsened by a semipermanent atmospheric gyre over the subcontinent. These factors were a driver of several major international field campaigns in the 1990s and early 2000s and attracted many scientists to the region. Some researchers were interested in understanding fundamental processes governing chemistry of the atmosphere and interaction with climate change. Others found favorable conditions for evaluating satellite- derived measurements of atmospheric properties and a changing land surface. With that background in mind a workshop on atmospheric chemistry was held in South Africa. Sponsored by the International Commission on Atmospheric Chemistry and Global Pollution (ICACGP; http://www.icacgp.org/), the workshop received generous support from Eskom, the South African power utility; and the Climatology Research Group of the University of the Witwatersrand, Johannesburg, South Africa.

  19. Towards a Comprehensive Seismic Velocity Model for the Broader Africa-Eurasia Collision Region, to Improve Nuclear Explosion Monitoring

    SciTech Connect

    der Lee, S v; Flanagan, M P; Rodgers, A J; Pasyanos, M E; Marone, F; Romanowicz, B

    2005-07-13

    We report on progress towards a new, comprehensive three-dimensional model of seismic velocity in a broad region encompassing the Middle East, northern Africa, the Mediterranean Sea, the Levant, the Arabian Peninsula, the Turkish-Iranian Plateau, Indus Valley, and the Hindu Kush. Our model will be based on regional waveform fits, surface wave group velocity measurements, teleseismic arrival times of S and P waves, receiver functions, and published results from active source experiments. We are in the process of assembling each of these data sets and testing the joint inversion for subsets of the data. Seismograms come from a variety of permanent and temporary seismic stations in the region. Some of the data is easily accessible through, for example, IRIS, while collection of other data is more involved. This work builds on ongoing work by Schmid et al. (GJI, 2004, and manuscript in preparation). In these proceedings we highlight our data sets and their inferences, demonstrate the proposed new data-inversion modeling methodology, discuss results from preliminary inversions of subsets of the data, and demonstrate the prediction of arrival times with three-dimensional velocity models. We compare our preliminary inversion results to the results of Schmid et al., and the predicted arrival times to ground-truth data from the NNSA Knowledge Base. Our data sets are simultaneously redundant and highly complementary. The combined data coverage will ensure that our three-dimensional model comprises the crust, the upper mantle, including the transition zone, and the top of the lower mantle, with spatially varying, but useful resolution. The region of interest is one of the most structurally heterogeneous in the world. Continental collision, rifting and sea-floor spreading, back-arc spreading, oceanic subduction, rotating micro plates, continental shelf, and stable platforms, are just some of the region's characteristics. Seismicity and the distribution of seismic stations are

  20. Ape malaria transmission and potential for ape-to-human transfers in Africa

    PubMed Central

    Makanga, Boris; Yangari, Patrick; Rahola, Nil; Rougeron, Virginie; Elguero, Eric; Boundenga, Larson; Moukodoum, Nancy Diamella; Okouga, Alain Prince; Arnathau, Céline; Durand, Patrick; Willaume, Eric; Ayala, Diego; Fontenille, Didier; Ayala, Francisco J.; Renaud, François; Ollomo, Benjamin; Prugnolle, Franck; Paupy, Christophe

    2016-01-01

    Recent studies have highlighted the large diversity of malaria parasites infecting African great apes (subgenus Laverania) and their strong host specificity. Although the existence of genetic incompatibilities preventing the cross-species transfer may explain host specificity, the existence of vectors with a high preference for a determined host represents another possibility. To test this hypothesis, we undertook a 15-mo-long longitudinal entomological survey in two forest regions of Gabon, where wild apes live, at different heights under the canopy. More than 2,400 anopheline mosquitoes belonging to 18 species were collected. Among them, only three species of Anopheles were found infected with ape Plasmodium: Anopheles vinckei, Anopheles moucheti, and Anopheles marshallii. Their role in transmission was confirmed by the detection of the parasites in their salivary glands. Among these species, An. vinckei showed significantly the highest prevalence of infection and was shown to be able to transmit parasites of both chimpanzees and gorillas. Transmission was also shown to be conditioned by seasonal factors and by the heights of capture under the canopy. Moreover, human landing catches of sylvan Anopheles demonstrated the propensity of these three vector species to feed on humans when available. Our results suggest therefore that the strong host specificity observed in the Laveranias is not linked to a specific association between the vertebrate host and the vector species and highlight the potential role of these vectors as bridge between apes and humans. PMID:27071123

  1. Climate, Environment and Early Human Innovation: Stable Isotope and Faunal Proxy Evidence from Archaeological Sites (98-59ka) in the Southern Cape, South Africa.

    PubMed

    Roberts, Patrick; Henshilwood, Christopher S; van Niekerk, Karen L; Keene, Petro; Gledhill, Andrew; Reynard, Jerome; Badenhorst, Shaw; Lee-Thorp, Julia

    2016-01-01

    The Middle Stone Age (MSA) of southern Africa, and in particular its Still Bay and Howiesons Poort lithic traditions, represents a period of dramatic subsistence, cultural, and technological innovation by our species, Homo sapiens. Climate change has frequently been postulated as a primary driver of the appearance of these innovative behaviours, with researchers invoking either climate instability as a reason for the development of buffering mechanisms, or environmentally stable refugia as providing a stable setting for experimentation. Testing these alternative models has proved intractable, however, as existing regional palaeoclimatic and palaeoenvironmental records remain spatially, stratigraphically, and chronologically disconnected from the archaeological record. Here we report high-resolution records of environmental shifts based on stable carbon and oxygen isotopes in ostrich eggshell (OES) fragments, faunal remains, and shellfish assemblages excavated from two key MSA archaeological sequences, Blombos Cave and Klipdrift Shelter. We compare these records with archaeological material remains in the same strata. The results from both sites, spanning the periods 98-73 ka and 72-59 ka, respectively, show significant changes in vegetation, aridity, rainfall seasonality, and sea temperature in the vicinity of the sites during periods of human occupation. While these changes clearly influenced human subsistence strategies, we find that the remarkable cultural and technological innovations seen in the sites cannot be linked directly to climate shifts. Our results demonstrate the need for scale-appropriate, on-site testing of behavioural-environmental links, rather than broader, regional comparisons.

  2. Climate, Environment and Early Human Innovation: Stable Isotope and Faunal Proxy Evidence from Archaeological Sites (98-59ka) in the Southern Cape, South Africa

    PubMed Central

    Keene, Petro; Gledhill, Andrew; Reynard, Jerome; Badenhorst, Shaw

    2016-01-01

    The Middle Stone Age (MSA) of southern Africa, and in particular its Still Bay and Howiesons Poort lithic traditions, represents a period of dramatic subsistence, cultural, and technological innovation by our species, Homo sapiens. Climate change has frequently been postulated as a primary driver of the appearance of these innovative behaviours, with researchers invoking either climate instability as a reason for the development of buffering mechanisms, or environmentally stable refugia as providing a stable setting for experimentation. Testing these alternative models has proved intractable, however, as existing regional palaeoclimatic and palaeoenvironmental records remain spatially, stratigraphically, and chronologically disconnected from the archaeological record. Here we report high-resolution records of environmental shifts based on stable carbon and oxygen isotopes in ostrich eggshell (OES) fragments, faunal remains, and shellfish assemblages excavated from two key MSA archaeological sequences, Blombos Cave and Klipdrift Shelter. We compare these records with archaeological material remains in the same strata. The results from both sites, spanning the periods 98–73 ka and 72–59 ka, respectively, show significant changes in vegetation, aridity, rainfall seasonality, and sea temperature in the vicinity of the sites during periods of human occupation. While these changes clearly influenced human subsistence strategies, we find that the remarkable cultural and technological innovations seen in the sites cannot be linked directly to climate shifts. Our results demonstrate the need for scale-appropriate, on-site testing of behavioural-environmental links, rather than broader, regional comparisons. PMID:27383620

  3. Smoking prevention and cessation in the Africa and Middle East region: a consensus draft guideline for healthcare providers--executive summary.

    PubMed

    Ali, Ahmed Yousif M; Safwat, Tarek; Onyemelukwe, Geoffrey; Otaibi, Moh'd Amin Al; Amir, Ashraf A; Nawas, Yousef N; Aouina, Hichem; Afif, Moulay Hicham; Bolliger, Chris T

    2012-01-01

    Despite the abundance of scientific evidence confirming the health consequences of smoking and other forms of tobacco use, the tobacco epidemic remains an important public health problem and by 2030 it is predicted that more than 80% of tobacco deaths will be in developing countries. In Africa and the Middle East, many local factors contribute to the initiation and maintenance of tobacco use. Although efforts to reduce the mortality and morbidity associated with smoking and tobacco dependence are underway, there is a need for guidance on how to utilize appropriate tobacco control policies and psychology- and pharmacology-based therapies to counter tobacco dependence as recommended by the Framework Convention on Tobacco Control (FCTC). A group of tobacco cessation experts from public health services and/or academic institutions in Africa and the Middle East participated in a series of four meetings held in Cairo, Cape Town, and Dubai between May 2008 and February 2011 to develop a draft guideline tailored to their region. This article provides the background to the development of this draft smoking cessation guideline and discusses how the recommendations can be implemented and progress monitored to promote both primary prevention and cessation of tobacco use within our countries. The draft guideline for Africa and the Middle East provides an important resource in combating the devastating effects of tobacco use in these regions which can be further localized through engagement with local stakeholders in the countries of the region.

  4. Demographic Inference Using Spectral Methods on SNP Data, with an Analysis of the Human Out-of-Africa Expansion

    PubMed Central

    Lukić, Sergio; Hey, Jody

    2012-01-01

    We present an implementation of a recently introduced method for estimating the allele-frequency spectrum under the diffusion approximation. For single-nucleotide polymorphism (SNP) frequency data from multiple populations, the method computes numerical solutions to the allele-frequency spectrum (AFS) under a complex model that includes population splitting events, migration, population expansion, and admixture. The solution to the diffusion partial differential equation (PDE) that mimics the evolutionary process is found by means of truncated polynomial expansions. In the absence of gene flow, our computation of frequency spectra yields exact results. The results are compared to those that use a finite-difference method and to forward diffusion simulations. In general, all the methods yield comparable results, although the polynomial-based approach is the most accurate in the weak-migration limit. Also, the economical use of memory attained by the polynomial expansions makes the study of models with four populations possible for the first time. The method was applied to a four-population model of the human expansion out of Africa and the peopling of the Americas, using the Environmental Genome Project (EGP) SNP database. Although our confidence intervals largely overlapped previous analyses of these data, some were significantly different. In particular, estimates of migration among African, European, and Asian populations were considerably lower than those in a previous study and the estimated time of migration out of Africa was earlier. The estimated time of founding of a human population outside of Africa was 52,000 years (95% confidence interval: 36,000–80,800 years). PMID:22865734

  5. Analysis of Human Accelerated DNA Regions Using Archaic Hominin Genomes

    PubMed Central

    Burbano, Hernán A.; Green, Richard E.; Maricic, Tomislav; Lalueza-Fox, Carles; de la Rasilla, Marco; Rosas, Antonio; Kelso, Janet; Pollard, Katherine S.; Lachmann, Michael; Pääbo, Svante

    2012-01-01

    Several previous comparisons of the human genome with other primate and vertebrate genomes identified genomic regions that are highly conserved in vertebrate evolution but fast-evolving on the human lineage. These human accelerated regions (HARs) may be regions of past adaptive evolution in humans. Alternatively, they may be the result of non-adaptive processes, such as biased gene conversion. We captured and sequenced DNA from a collection of previously published HARs using DNA from an Iberian Neandertal. Combining these new data with shotgun sequence from the Neandertal and Denisova draft genomes, we determine at least one archaic hominin allele for 84% of all positions within HARs. We find that 8% of HAR substitutions are not observed in the archaic hominins and are thus recent in the sense that the derived allele had not come to fixation in the common ancestor of modern humans and archaic hominins. Further, we find that recent substitutions in HARs tend to have come to fixation faster than substitutions elsewhere in the genome and that substitutions in HARs tend to cluster in time, consistent with an episodic rather than a clock-like process underlying HAR evolution. Our catalog of sequence changes in HARs will help prioritize them for functional studies of genomic elements potentially responsible for modern human adaptations. PMID:22412940

  6. Capacity building and predictors of success for HIV-1 drug resistance testing in the Asia-Pacific region and Africa

    PubMed Central

    Land, Sally; Zhou, Julian; Cunningham, Philip; Sohn, Annette H; Singtoroj, Thida; Katzenstein, David; Mann, Marita; Sayer, David; Kantor, Rami

    2013-01-01

    Background The TREAT Asia Quality Assessment Scheme (TAQAS) was developed as a quality assessment programme through expert education and training, for laboratories in the Asia-Pacific and Africa that perform HIV drug-resistance (HIVDR) genotyping. We evaluated the programme performance and factors associated with high-quality HIVDR genotyping. Methods Laboratories used their standard protocols to test panels of human immunodeficiency virus (HIV)-positive plasma samples or electropherograms. Protocols were documented and performance was evaluated according to a newly developed scoring system, agreement with panel-specific consensus sequence, and detection of drug-resistance mutations (DRMs) and mixtures of wild-type and resistant virus (mixtures). High-quality performance was defined as detection of ≥95% DRMs. Results Over 4.5 years, 23 participating laboratories in 13 countries tested 45 samples (30 HIV-1 subtype B; 15 non-B subtypes) in nine panels. Median detection of DRMs was 88–98% in plasma panels and 90–97% in electropherogram panels. Laboratories were supported to amend and improve their test outcomes as appropriate. Three laboratories that detected <80% DRMs in early panels demonstrated subsequent improvement. Sample complexity factors – number of DRMs (p<0.001) and number of DRMs as mixtures (p<0.001); and laboratory performance factors – detection of mixtures (p<0.001) and agreement with consensus sequence (p<0.001), were associated with high performance; sample format (plasma or electropherogram), subtype and genotyping protocol were not. Conclusion High-quality HIVDR genotyping was achieved in the TAQAS collaborative laboratory network. Sample complexity and detection of mixtures were associated with performance quality. Laboratories conducting HIVDR genotyping are encouraged to participate in quality assessment programmes. PMID:23845227

  7. On the added value of the regional climate model REMO in the assessment of climate change signal over Central Africa

    NASA Astrophysics Data System (ADS)

    Fotso-Nguemo, Thierry C.; Vondou, Derbetini A.; Pokam, Wilfried M.; Djomou, Zéphirin Yepdo; Diallo, Ismaïla; Haensler, Andreas; Tchotchou, Lucie A. Djiotang; Kamsu-Tamo, Pierre H.; Gaye, Amadou T.; Tchawoua, Clément

    2017-02-01

    In this paper, the regional climate model REMO is used to investigate the added value of downscaling low resolutions global climate models (GCMs) and the climate change projections over Central Africa. REMO was forced by two GCMs (EC-Earth and MPI-ESM), for the period from 1950 to 2100 under the Representative Concentration Pathway 8.5 scenario. The performance of the REMO simulations for current climate is compared first with REMO simulation driven by ERA-Interim reanalysis, then by the corresponding GCMs in order to determine whether REMO outputs are able to effectively lead to added value at local scale. We found that REMO is generally able to better represent some aspects of the rainfall inter-annual variability, the daily rainfall intensity distribution as well as the intra-seasonal variability of the Central African monsoon, though few biases are still evident. It is also found that the boundary conditions strongly influences the spatial distribution of seasonal 2-m temperature and rainfall. From the analysis of the climate change signal from the present period 1976-2005 to the future 2066-2095, we found that all models project a warming at the end of the twenty-first century although the details of the climate change differ between REMO and the driving GCMs, specifically in REMO where we observe a general decrease in rainfall. This rainfall decrease is associated with delayed onset and anticipated recession of the Central African monsoon and a shortening of the rainy season. Small-scales variability of the climate change signal for 2-m temperature are usually smaller than that of the large-scales climate change part. For rainfall however, small-scales induce change of about 70% compared to the present climate statistics.

  8. Recombination in the Human Pseudoautosomal Region PAR1

    PubMed Central

    Hinch, Anjali G.; Altemose, Nicolas; Noor, Nudrat; Donnelly, Peter; Myers, Simon R.

    2014-01-01

    The pseudoautosomal region (PAR) is a short region of homology between the mammalian X and Y chromosomes, which has undergone rapid evolution. A crossover in the PAR is essential for the proper disjunction of X and Y chromosomes in male meiosis, and PAR deletion results in male sterility. This leads the human PAR with the obligatory crossover, PAR1, to having an exceptionally high male crossover rate, which is 17-fold higher than the genome-wide average. However, the mechanism by which this obligatory crossover occurs remains unknown, as does the fine-scale positioning of crossovers across this region. Recent research in mice has suggested that crossovers in PAR may be mediated independently of the protein PRDM9, which localises virtually all crossovers in the autosomes. To investigate recombination in this region, we construct the most fine-scale genetic map containing directly observed crossovers to date using African-American pedigrees. We leverage recombination rates inferred from the breakdown of linkage disequilibrium in human populations and investigate the signatures of DNA evolution due to recombination. Further, we identify direct PRDM9 binding sites using ChIP-seq in human cells. Using these independent lines of evidence, we show that, in contrast with mouse, PRDM9 does localise peaks of recombination in the human PAR1. We find that recombination is a far more rapid and intense driver of sequence evolution in PAR1 than it is on the autosomes. We also show that PAR1 hotspot activities differ significantly among human populations. Finally, we find evidence that PAR1 hotspot positions have changed between human and chimpanzee, with no evidence of sharing among the hottest hotspots. We anticipate that the genetic maps built and validated in this work will aid research on this vital and fascinating region of the genome. PMID:25033397

  9. Recombination in the human Pseudoautosomal region PAR1.

    PubMed

    Hinch, Anjali G; Altemose, Nicolas; Noor, Nudrat; Donnelly, Peter; Myers, Simon R

    2014-07-01

    The pseudoautosomal region (PAR) is a short region of homology between the mammalian X and Y chromosomes, which has undergone rapid evolution. A crossover in the PAR is essential for the proper disjunction of X and Y chromosomes in male meiosis, and PAR deletion results in male sterility. This leads the human PAR with the obligatory crossover, PAR1, to having an exceptionally high male crossover rate, which is 17-fold higher than the genome-wide average. However, the mechanism by which this obligatory crossover occurs remains unknown, as does the fine-scale positioning of crossovers across this region. Recent research in mice has suggested that crossovers in PAR may be mediated independently of the protein PRDM9, which localises virtually all crossovers in the autosomes. To investigate recombination in this region, we construct the most fine-scale genetic map containing directly observed crossovers to date using African-American pedigrees. We leverage recombination rates inferred from the breakdown of linkage disequilibrium in human populations and investigate the signatures of DNA evolution due to recombination. Further, we identify direct PRDM9 binding sites using ChIP-seq in human cells. Using these independent lines of evidence, we show that, in contrast with mouse, PRDM9 does localise peaks of recombination in the human PAR1. We find that recombination is a far more rapid and intense driver of sequence evolution in PAR1 than it is on the autosomes. We also show that PAR1 hotspot activities differ significantly among human populations. Finally, we find evidence that PAR1 hotspot positions have changed between human and chimpanzee, with no evidence of sharing among the hottest hotspots. We anticipate that the genetic maps built and validated in this work will aid research on this vital and fascinating region of the genome.

  10. Paleoenvironmental and Human Behavioral Implications of the Boegoeberg 1 Late Pleistocene Hyena Den, Northern Cape Province, South Africa

    NASA Astrophysics Data System (ADS)

    Klein, Richard G.; Cruz-Uribe, Kathryn; Halkett, David; Hart, Tim; Parkington, John E.

    1999-11-01

    Boegoeberg 1 (BOG1) is located on the Atlantic coast of South Africa, 850 km north of Cape Town. The site is a shallow rock shelter in the side of a sand-choked gully that was emptied by diamond miners. Abundant coprolites, chewed bones, and partially digested bones implicate hyenas as the bone accumulators. The location of the site, quantity of bones, and composition of the fauna imply it was a brown hyena nursery den. The abundance of Cape fur seal bones shows that the hyenas had ready access to the coast. Radiocarbon dates place the site before 37,000 14C yr ago, while the large average size of the black-backed jackals and the presence of extralimital ungulates imply cool, moist conditions, probably during the early part of the last glaciation (isotope stage 4 or stage 3 before 37,000 14C yr ago) or perhaps during one of the cooler phases (isotope substages 5d or 5b) within the last interglaciation. Comparisons of the BOG1 seal bones to those from regional Middle Stone Age (MSA) and Later Stone Age (LSA) archeological sites suggest (1) that hyena and human seal accumulations can be distinguished by a tendency for vertebrae to be much more common in a hyena accumulation and (2) that hyena and LSA accumulations can be distinguished by a tendency for hyena-accumulated seals to represent a much wider range of individual seal ages. Differences in the way hyenas and people dismember, transport, and consume seal carcasses probably explain the contrast in skeletal part representation, while differences in season of occupation explain the contrast in seal age representation. Like modern brown hyenas, the BOG1 hyenas probably occupied the coast year-round, while the LSA people focused their coastal visits on the August-October interval when nine-to-eleven-month-old seals were abundant. The MSA sample from Klasies River Mouth Cave 1 resembles BOG1 in seal age composition, suggesting that unlike LSA people, MSA people obtained seals more or less throughout the year.

  11. Epidemiology and interactions of Human Immunodeficiency Virus – 1 and Schistosoma mansoni in sub-Saharan Africa

    PubMed Central

    2013-01-01

    Human Immunodeficiency Virus-1/AIDS and Schistosoma mansoni are widespread in sub-Saharan Africa and co-infection occurs commonly. Since the early 1990s, it has been suggested that the two infections may interact and potentiate the effects of each other within co-infected human hosts. Indeed, S. mansoni infection has been suggested to be a risk factor for HIV transmission and progression in Africa. If so, it would follow that mass deworming could have beneficial effects on HIV-1 transmission dynamics. The epidemiology of HIV in African countries is changing, shifting from urban to rural areas where the prevalence of Schistosoma mansoni is high and public health services are deficient. On the other side, the consequent pathogenesis of HIV-1/S. mansoni co-infection remains unknown. Here we give an account of the epidemiology of HIV-1 and S. mansoni, discuss co-infection and possible biological causal relationships between the two infections, and the potential impact of praziquantel treatment on HIV-1 viral loads, CD4+ counts and CD4+/CD8+ ratio. Our review of the available literature indicates that there is evidence to support the hypothesis that S. mansoni infections can influence the replication of the HIV-1, cell-to-cell transmission, as well as increase HIV progression as measured by reduced CD4+ T lymphocytes counts. If so, then deworming of HIV positive individuals living in endemic areas may impact on HIV-1 viral loads and CD4+ T lymphocyte counts. PMID:23849678

  12. Early human settlements in Northern Africa: paleomagnetic evidence from the Ain Hanech Formation (northeastern Algeria)

    NASA Astrophysics Data System (ADS)

    Parés, J. M.; Sahnouni, M.; Van der Made, J.; Pérez-González, A.; Harichane, Z.; Derradji, A.; Medig, M.

    2014-09-01

    The question of the earliest hominid settlements in northern Africa has been under debate for a number of years due to the lack of precise chronologies. Here we present new paleomagnetic data that supports an Olduvai Subchron age for the archaeological sites at Ain Hanech and El-Kherba, in northern Algeria. Our study is based on a 22 m-thick magnetostratigraphy of the Ain Hanech Formation, which includes contextualized Oldowan and Acheulian lithic tools. Characteristic remanent magnetization directions were obtained from both thermal and alternating field demagnetization procedures of specimens from twenty five sampled horizons. Our results reveal the presence of the Olduvai Subchron in the upper part of the stratigraphic section, constraining the age of these important archaeological sites in northern Africa.

  13. Human Capital Formation in the Gulf and MENA Region.

    ERIC Educational Resources Information Center

    Shaw, Ken E.

    2001-01-01

    Recent developments in human capital formation theories are particularly relevant to the Gulf and Middle Eastern and North African regions. Discusses recent western reconfigurations of the theory, noting how much local work must be done to reshape theory appropriately in the Middle East and explaining how issues relating to employment, education,…

  14. Implications of Special Regions to Conducting Human Activities on Mars

    NASA Astrophysics Data System (ADS)

    Rummel, J. D.; Barlow, N. G.; Beaty, D. W.; Jones, M. A.; Hipkin, V.

    2014-12-01

    A MEPAG Science Analysis Group (SAG) has undertaken an analysis of Special Regions (SR) on Mars—regions where indigenous martian life could exist or where Earth microbes, if introduced, could survive and reproduce. The SR-SAG has considered the impact of SR on future human activities on the martian surface. Human exploration requires access to in-situ resources, some of which may be found in SR. Water and oxygen for ISRU are found in the atmosphere, surface/near-surface ice, hydrated minerals, and perchlorates. Water ice is most abundant at latitudes poleward of ~60 degrees, but polar darkness, cold temperatures, and CO2 degassing present hazards to human operations in these regions. Accessible water is more limited toward the equator, though temperature and solar energy conditions become more favorable. The possible presence of liquid water in Recurring Slope Lineae and active gullies leads to their treatment as SR. Fuel for surface operations and propellants for crew ascent could be manufactured from the martian atmosphere and surface materials, but dust in the atmosphere may clog ISRU equipment and perchlorate is toxic to humans. Power may be produced from solar or nuclear energy. Reliance on solar energy limits operations to the equatorial zone where easily accessible ice resources are limited. Nuclear power allows surface operations at a range of latitudes, but waste heat could convert some non-SR into SR. Radiation shielding is necessary for long-term human operations on Mars and could be obtained by deposition of regolith or by water storage in tanks or as ice around habitats, or the use of underground habitats. SR-SAG recognizes that it will be impossible for all human-associated processes and operations to be conducted within entirely closed systems. Protocols need to be established so (1) human missions to Mars will not contaminate SR nor be contaminated by materials from them, and (2) human activities on Mars will avoid converting areas into SR.

  15. New Target Regions for Human Hypertension via Comparative Genomics

    PubMed Central

    Stoll, Monika; Kwitek-Black, Anne E.; Cowley, Allen W.; Harris, Eugenie L.; Harrap, Stephen B.; Krieger, José E.; Printz, Morton P.; Provoost, Abraham P.; Sassard, Jean; Jacob, Howard J.

    2000-01-01

    Models of human disease have long been used to understand the basic pathophysiology of disease and to facilitate the discovery of new therapeutics. However, as long as models have been used there have been debates about the utility of these models and their ability to mimic clinical disease at the phenotypic level. The application of genetic studies to both humans and model systems allows for a new paradigm, whereby a novel comparative genomics strategy combined with phenotypic correlates can be used to bridge between clinical relevance and model utility. This study presents a comparative genomic map for “candidate hypertension loci in humans” based on translating QTLs between rat and human, predicting 26 chromosomal regions in the human genome that are very likely to harbor hypertension genes. The predictive power appears robust, as several of these regions have also been implicated in mouse, suggesting that these regions represent primary targets for the development of SNPs for linkage disequilibrium testing in humans and/or provide a means to select specific models for additional functional studies and the development of new therapeutics. PMID:10779487

  16. History and origin of the HIV-1 subtype C epidemic in South Africa and the greater southern African region

    PubMed Central

    Wilkinson, Eduan; Engelbrecht, Susan; de Oliveira, Tulio

    2015-01-01

    HIV has spread at an alarming rate in South Africa, making it the country with the highest number of HIV infections. Several studies have investigated the histories of HIV-1 subtype C epidemics but none have done so in the context of social and political transformation in southern Africa. There is a need to understand how these processes affects epidemics, as socio-political transformation is a common and on-going process in Africa. Here, we genotyped strains from the start of the epidemic and applied phylodynamic techniques to determine the history of the southern Africa and South African epidemic from longitudinal sampled data. The southern African epidemic’s estimated dates of origin was placed around 1960 (95% HPD 1956–64), while dynamic reconstruction revealed strong growth during the 1970s and 80s. The South African epidemic has a similar origin, caused by multiple introductions from neighbouring countries, and grew exponentially during the 1980s and 90s, coinciding with socio-political changes in South Africa. These findings provide an indication as to when the epidemic started and how it has grown, while the inclusion of sequence data from the start of the epidemic provided better estimates. The epidemic have stabilized in recent years with the expansion of antiretroviral therapy. PMID:26574165

  17. History and origin of the HIV-1 subtype C epidemic in South Africa and the greater southern African region.

    PubMed

    Wilkinson, Eduan; Engelbrecht, Susan; de Oliveira, Tulio

    2015-11-17

    HIV has spread at an alarming rate in South Africa, making it the country with the highest number of HIV infections. Several studies have investigated the histories of HIV-1 subtype C epidemics but none have done so in the context of social and political transformation in southern Africa. There is a need to understand how these processes affects epidemics, as socio-political transformation is a common and on-going process in Africa. Here, we genotyped strains from the start of the epidemic and applied phylodynamic techniques to determine the history of the southern Africa and South African epidemic from longitudinal sampled data. The southern African epidemic's estimated dates of origin was placed around 1960 (95% HPD 1956-64), while dynamic reconstruction revealed strong growth during the 1970s and 80s. The South African epidemic has a similar origin, caused by multiple introductions from neighbouring countries, and grew exponentially during the 1980s and 90s, coinciding with socio-political changes in South Africa. These findings provide an indication as to when the epidemic started and how it has grown, while the inclusion of sequence data from the start of the epidemic provided better estimates. The epidemic have stabilized in recent years with the expansion of antiretroviral therapy.

  18. Psychometric evaluation of the COPD assessment test: data from the BREATHE study in the Middle East and North Africa region.

    PubMed

    Jones, Paul W; Shahrour, Naem; Nejjari, Chakib; Lahlou, Aicha; Doble, Adam; Rashid, Nauman; El Hasnaoui, Abdelkader

    2012-12-01

    The objective of this study was to assess the validity and performance of the Arabic and Turkish versions of the COPD Assessment Test (CAT) for evaluating the severity and impact of COPD symptoms. The data were obtained from the BREATHE study in the Middle East and North Africa region, a large general population survey of COPD conducted in ten countries of the region (Algeria, Egypt, Jordan, Lebanon, Morocco, Saudi Arabia, Syria, Tunisia, Turkey and United Arab Emirates), using a standardised methodology. A total of 62,086 subjects were screened, of whom a random sample of 5,681 subjects were administered the CAT by telephone. 5,639 evaluable questionnaires were recovered, representing a completion rate of 99%. In addition, the CAT was administered to an additional 833 subjects fulfilling the epidemiological diagnostic criteria for COPD. Mean scores in the general population were 6.99 ± 6.91 for the Arabic version and 9.88 ± 9.04 for the Turkish version. In patients with COPD, mean scores were 16.2 ± 9.1 and 20.9 ± 10.2 respectively. Scores were consistently higher in smokers than in non-smokers. In the general population, the proportion of respondents fulfilling criteria for COPD rose with higher CAT scores, and particularly above the 80th percentile, where 63% of COPD cases were to be found. This suggests that the CAT may be useful as a case-finding tool in the general population. In the COPD population, healthcare resource consumption rose linearly with CAT score above a threshold score of twenty, arguing in favour of the good criterion validity of the CAT. The internal consistency of the CAT was high (Cronbach's α 0.85 for the Arabic and 0.86 for the Turkish versions) and the factorial structure was unidimensional. In conclusion, this study performed in Arabic and Turkish speaking populations confirms the utility and validity of the CAT as a simple tool to collect data on the severity and impact of COPD symptoms, and suggests that it may potentially be

  19. Phylogenetic characterisation of Taenia tapeworms in spotted hyenas and reconsideration of the "Out of Africa" hypothesis of Taenia in humans.

    PubMed

    Terefe, Yitagele; Hailemariam, Zerihun; Menkir, Sissay; Nakao, Minoru; Lavikainen, Antti; Haukisalmi, Voitto; Iwaki, Takashi; Okamoto, Munehiro; Ito, Akira

    2014-07-01

    The African origin of hominins suggests that Taenia spp. in African carnivores are evolutionarily related to the human-infecting tapeworms Taenia solium, Taenia saginata and Taenia asiatica. Nevertheless, the hypothesis has not been verified through molecular phylogenetics of Taenia. This study aimed to perform phylogenetic comparisons between Taenia spp. from African hyenas and the congeneric human parasites. During 2010-2013, 233 adult specimens of Taenia spp. were collected from 11 spotted hyenas in Ethiopia. A screening based on short DNA sequences of the cytochrome c oxidase subunit 1 gene classified the samples into four mitochondrial lineages designated as I-IV. DNA profiles of nuclear genes for DNA polymerase delta (pold) and phosphoenolpyruvate carboxykinase (pepck) showed that lineages II and III can be assigned as two independent species. Common haplotypes of pold and pepck were frequently found in lineages I and IV, suggesting that they constitute a single species. Morphological observations suggested that lineage II is Taenia crocutae, but the other lineages were morphologically inconsistent with known species, suggesting the involvement of two new species. A phylogenetic tree of Taenia spp. was reconstructed by the maximum likelihood method using all protein-coding genes of their mitochondrial genomes. The tree clearly demonstrated that T. crocutae is sister to T. saginata and T. asiatica, whereas T. solium was confirmed to be sister to the brown bear tapeworm, Taenia arctos. The tree also suggested that T. solium and T. arctos are related to two species of Taenia in hyenas, corresponding to lineages I+IV and III. These results may partially support the African origin of human-infecting Taenia spp., but there remains a possibility that host switching of Taenia to hominins was not confined to Africa. Additional taxa from African carnivores are needed for further testing of the "Out of Africa" hypothesis of Taenia in humans.

  20. Tracing past human male movements in northern/eastern Africa and western Eurasia: new clues from Y-chromosomal haplogroups E-M78 and J-M12.

    PubMed

    Cruciani, Fulvio; La Fratta, Roberta; Trombetta, Beniamino; Santolamazza, Piero; Sellitto, Daniele; Colomb, Eliane Beraud; Dugoujon, Jean-Michel; Crivellaro, Federica; Benincasa, Tamara; Pascone, Roberto; Moral, Pedro; Watson, Elizabeth; Melegh, Bela; Barbujani, Guido; Fuselli, Silvia; Vona, Giuseppe; Zagradisnik, Boris; Assum, Guenter; Brdicka, Radim; Kozlov, Andrey I; Efremov, Georgi D; Coppa, Alfredo; Novelletto, Andrea; Scozzari, Rosaria

    2007-06-01

    Detailed population data were obtained on the distribution of novel biallelic markers that finely dissect the human Y-chromosome haplogroup E-M78. Among 6,501 Y chromosomes sampled in 81 human populations worldwide, we found 517 E-M78 chromosomes and assigned them to 10 subhaplogroups. Eleven microsatellite loci were used to further evaluate subhaplogroup internal diversification. The geographic and quantitative analyses of haplogroup and microsatellite diversity is strongly suggestive of a northeastern African origin of E-M78, with a corridor for bidirectional migrations between northeastern and eastern Africa (at least 2 episodes between 23.9-17.3 ky and 18.0-5.9 ky ago), trans-Mediterranean migrations directly from northern Africa to Europe (mainly in the last 13.0 ky), and flow from northeastern Africa to western Asia between 20.0 and 6.8 ky ago. A single clade within E-M78 (E-V13) highlights a range expansion in the Bronze Age of southeastern Europe, which is also detected by haplogroup J-M12. Phylogeography pattern of molecular radiation and coalescence estimates for both haplogroups are similar and reveal that the genetic landscape of this region is, to a large extent, the consequence of a recent population growth in situ rather than the result of a mere flow of western Asian migrants in the early Neolithic. Our results not only provide a refinement of previous evolutionary hypotheses but also well-defined time frames for past human movements both in northern/eastern Africa and western Eurasia.

  1. Molecular epidemiology of 58 new African human T-cell leukemia virus type 1 (HTLV-1) strains: identification of a new and distinct HTLV-1 molecular subtype in Central Africa and in Pygmies.

    PubMed Central

    Mahieux, R; Ibrahim, F; Mauclere, P; Herve, V; Michel, P; Tekaia, F; Chappey, C; Garin, B; Van Der Ryst, E; Guillemain, B; Ledru, E; Delaporte, E; de The, G; Gessain, A

    1997-01-01

    To gain new insights on the origin, evolution, and modes of dissemination of human T-cell leukemia virus type I (HTLV-1), we performed a molecular analysis of 58 new African HTLV-1 strains (18 from West Africa, 36 from Central Africa, and 4 from South Africa) originating from 13 countries. Of particular interest were eight strains from Pygmies of remote areas of Cameroon and the Central African Republic (CAR), considered to be the oldest inhabitants of these regions. Eight long-term activated T-cell lines producing HTLV-1 gag and env antigens were established from peripheral blood mononuclear cell cultures of HTLV-1 seropositive individuals, including three from Pygmies. A fragment of the env gene encompassing most of the gp21 transmembrane region was sequenced for the 58 new strains, while the complete long terminal repeat (LTR) region was sequenced for 9 strains, including 4 from Pygmies. Comparative sequence analyses and phylogenetic studies performed on both the env and LTR regions by the neighbor-joining and DNA parsimony methods demonstrated that all 22 strains from West and South Africa belong to the widespread cosmopolitan subtype (also called HTLV-1 subtype A). Within or alongside the previously described Zairian cluster (HTLV-1 subtype B), we discovered a number of new HTLV-1 variants forming different subgroups corresponding mainly to the geographical origins of the infected persons, Cameroon, Gabon, and Zaire. Six of the eight Pygmy strains clustered together within this Central African subtype, suggesting a common origin. Furthermore, three new strains (two originating from Pygmies from Cameroon and the CAR, respectively, and one from a Gabonese individual) were particularly divergent and formed a distinct new phylogenetic cluster, characterized by specific mutations and occupying in most analyses a unique phylogenetic position between the large Central African genotype (HTLV-1 subtype B) and the Melanesian subtype (HTLV-1 subtype C). We have

  2. Mobile Gis: a Tool for Informal Settlement Occupancy Audit to Improve Integrated Human Settlement Implementation in Ekurhuleni, South Africa

    NASA Astrophysics Data System (ADS)

    Mokoena, B. T.; Musakwa, W.

    2016-06-01

    Upgrading and relocating people in informal settlements requires consistent commitment, good strategies and systems so as to improve the lives of those who live in them. In South Africa, in order to allocate subsidised housing to beneficiaries of an informal settlement, beneficiary administration needs to be completed to determine the number of people who qualify for a subsidised house. Conventional methods of occupancy audits are often unreliable, cumbersome and non-spatial. Accordingly, this study proposes the use of mobile GIS to conduct these audits to provide up-to-date, accurate, comprehensive and real-time data so as to facilitate the development of integrated human settlements. An occupancy audit was subsequently completed for one of the communities in the Ekurhuleni municipality, Gauteng province, using web-based mobile GIS as a solution to providing smart information through evidence based decision making. Fieldworkers accessed the off-line capturing module on a mobile device recording GPS coordinates, socio-economic information and photographs. The results of this audit indicated that only 56.86% of the households residing within the community could potentially benefit from receiving a subsidised house. Integrated residential development, which includes fully and partially subsidised housing, serviced stands and some fully bonded housing opportunities, would then be key to adequately providing access to suitable housing options within a project in a post-colonial South Africa, creating new post-1994 neighbourhoods, in line with policy. The use of mobile GIS therefore needs to be extended to other informal settlement upgrading projects in South Africa.

  3. Social networks and mental health among people living with human immunodeficiency virus (HIV) in Johannesburg, South Africa.

    PubMed

    Odek, Willis Omondi

    2014-01-01

    People living with human immunodeficiency virus (PLHIV) in developing countries can live longer due to improved treatment access, and a deeper understanding of determinants of their quality of life is critical. This study assessed the link between social capital, operationally defined in terms of social networks (group-based and personal social networks) and access to network resources (access to material and non-material resources and social support) and health-related quality of life (HRQoL) among 554 (55% female) adults on HIV treatment through South Africa's public health system. Female study participants were involved with more group-based social networks but had fewer personal social networks in comparison to males. Access to network resources was higher among females and those from larger households but lower among older study participants. Experience of social support significantly increased with household economic status and duration at current residence. Social capital indicators were unrelated to HIV disease status indicators, including duration since diagnosis, CD4 count and viral load. Only a minority (13%) of study participants took part in groups formed by and for predominantly PLHIV (HIV support groups), and participation in such groups was unrelated to their mental or physical health. Personal rather than group-linked social networks and access to network resources were significantly associated with mental but not physical health, after controlling for sociodemographic characteristics. The findings of limited participation in HIV support groups and that the participation in such groups was not significantly associated with physical or mental health may suggest efforts among PLHIV in South Africa to normalise HIV as a chronic illness through broad-based rather than HIV-status bounded social participation, as a strategy for deflecting stigma. Further research is required to examine the effects of HIV treatment on social networking and participation

  4. Chromosome region-specific libraries for human genome analysis

    SciTech Connect

    Kao, Fa-Ten.

    1992-08-01

    During the grant period progress has been made in the successful demonstration of regional mapping of microclones derived from microdissection libraries; successful demonstration of the feasibility of converting microclones with short inserts into yeast artificial chromosome clones with very large inserts for high resolution physical mapping of the dissected region; Successful demonstration of the usefulness of region-specific microclones to isolate region-specific cDNA clones as candidate genes to facilitate search for the crucial genes underlying genetic diseases assigned to the dissected region; and the successful construction of four region-specific microdissection libraries for human chromosome 2, including 2q35-q37, 2q33-q35, 2p23-p25 and 2p2l-p23. The 2q35-q37 library has been characterized in detail. The characterization of the other three libraries is in progress. These region-specific microdissection libraries and the unique sequence microclones derived from the libraries will be valuable resources for investigators engaged in high resolution physical mapping and isolation of disease-related genes residing in these chromosomal regions.

  5. Vegetation-climate feedback causes reduced precipitation and tropical rainforest cover in CMIP5 regional Earth system model simulation over Africa

    NASA Astrophysics Data System (ADS)

    Wu, M.; Smith, B.; Samuelsson, P.; Rummukainen, M.; Schurgers, G.

    2012-12-01

    We applied a coupled regional climate-vegetation model, RCA-GUESS (Smith et al. 2011), over the CORDEX Africa domain, forced by boundary conditions from a CanESM2 CMIP5 simulation under the RCP8.5 future climate scenario. The simulations were from 1961 to 2100 and covered the African continent at a horizontal grid spacing of 0.44°. RCA-GUESS simulates changes in the phenology, productivity, relative cover and population structure of up to eight plant function types (PFTs) in response to forcing from the climate part of the model. These vegetation changes feed back to simulated climate through dynamic adjustments in surface energy fluxes and surface properties. Changes in the net ecosystem-atmosphere carbon flux and its components net primary production (NPP), heterotrophic respiration and emissions from biomass burning were also simulated but do not feed back to climate in our model. Constant land cover was assumed. We compared simulations with and without vegetation feedback switched "on" to assess the influence of vegetation-climate feedback on simulated climate, vegetation and ecosystem carbon cycling. Both positive and negative warming feedbacks were identified in different parts of Africa. In the Sahel savannah zone near 15°N, reduced vegetation cover and productivity, and mortality caused by a deterioration of soil water conditions led to a positive warming feedback mediated by decreased evapotranspiration and increased sensible heat flux between vegetation and the atmosphere. In the equatorial rainforest stronghold region of central Africa, a feedback syndrome characterised by reduced plant production and LAI, a dominance shift from tropical trees to grasses, reduced soil water and reduced rainfall was identified. The likely underlying mechanism was a decline in evaporative water recycling associated with sparser vegetation cover, reminiscent of Earth system model studies in which a similar feedback mechanism was simulated to force dieback of tropical

  6. Regional specialization within the human striatum for diverse psychological functions

    PubMed Central

    Pauli, Wolfgang M.; O’Reilly, Randall C.; Wager, Tor D.

    2016-01-01

    Decades of animal and human neuroimaging research have identified distinct, but overlapping, striatal zones, which are interconnected with separable corticostriatal circuits, and are crucial for the organization of functional systems. Despite continuous efforts to subdivide the human striatum based on anatomical and resting-state functional connectivity, characterizing the different psychological processes related to each zone remains a work in progress. Using an unbiased, data-driven approach, we analyzed large-scale coactivation data from 5,809 human imaging studies. We (i) identified five distinct striatal zones that exhibited discrete patterns of coactivation with cortical brain regions across distinct psychological processes and (ii) identified the different psychological processes associated with each zone. We found that the reported pattern of cortical activation reliably predicted which striatal zone was most strongly activated. Critically, activation in each functional zone could be associated with distinct psychological processes directly, rather than inferred indirectly from psychological functions attributed to associated cortices. Consistent with well-established findings, we found an association of the ventral striatum (VS) with reward processing. Confirming less well-established findings, the VS and adjacent anterior caudate were associated with evaluating the value of rewards and actions, respectively. Furthermore, our results confirmed a sometimes overlooked specialization of the posterior caudate nucleus for executive functions, often considered the exclusive domain of frontoparietal cortical circuits. Our findings provide a precise functional map of regional specialization within the human striatum, both in terms of the differential cortical regions and psychological functions associated with each striatal zone. PMID:26831091

  7. Environmental pollutants and diseases of sexual development in humans and wildlife in South Africa: harbingers of impact on overall health?

    PubMed

    Riana Bornman, M S; Bouwman, Hindrik

    2012-08-01

    This study deals with disorders of sexual development in humans, wildlife and animals in an urban nature reserve (RNR) and a currently DDT-sprayed malarial area. High levels of oestrogenic chemical residues in water, sediment and tissue; skewed sex ratios; reduced biodiversity; gonadal malformations in sharptooth catfish and freshwater snails; intersex in catfish; and impaired spermatogenesis in catfish and striped mouse are of serious concern in the RNR. Persistent eggshell thinning in African darter eggs, intersex in male Mozambican tilapia, follicular atresia in females and impaired spermatogenesis in males following laboratory exposure of parent fish to environmentally relevant DDT and DDE concentrations, and abnormalities in freshwater snails were found in the DDT-sprayed area. Human studies related to DDT exposure indicated impaired semen quality, a weak association with sperm chromatin defects and higher risks for external urogenital birth defects in those who were born to mothers whose houses were sprayed and those who were homemakers (stay at home mother) instead of being employed. These findings indicate that diseases of sexual development occurred in both human and wildlife populations exposed to environmental endocrine disruptor chemicals in South Africa. The chemical mixtures, possibly related to disorders of sexual differentiation (DSD), were very different between the two. However, DSD occurred concurrently in the malarial area, possibly indicating that humans and wildlife shared exposures. Moreover, it emphasizes the importance of suspecting disease in the other when disease is found in either human or wildlife populations.

  8. Contemporary Problems in Africa.

    ERIC Educational Resources Information Center

    O'Meara, Patrick; Winchester, N. Brian

    1987-01-01

    Provides a brief overview of political and economic developments of the past 25 years in Africa. Maintains this was a period of experimentation with vast differences in the ways in which governments dealt with human and natural problems. (JDH)

  9. Human rights violations and smoking status among South African adults enrolled in the South Africa Stress and Health (SASH) study

    PubMed Central

    Dutra, Lauren M; Williams, David R; Gupta, Jhumka; Kawachi, Ichiro; Okechukwu, Cassandra A

    2014-01-01

    Despite South Africa’s history of violent political conflict, and the link between stressful experiences and smoking in the literature, no public health study has examined South Africans’ experiences of human rights violations and smoking. Using data from participants in the nationally representative cross-sectional South Africa Stress and Health study (SASH), this analysis examined the association between respondent smoking status and both human rights violations experienced by the respondent and violations experienced by the respondents’ close friends and family members. SAS-Callable SUDAAN was used to construct separate log-binomial models by political affiliation during apartheid (government or liberation supporters). In comparison to those who reported no violations, in adjusted analyses, government supporters who reported violations of themselves but not others (RR=1.76, 95%CI: 1.25–2.46) had a significantly higher smoking prevalence. In comparison to liberation supporters who reported no violations, those who reported violations of self only (RR=1.56, 95%CI: 1.07–2.29), close others only (RR=1.97, 95%CI: 1.12–3.47), or violations of self and close others due to close others’ political beliefs and the respondent’s political beliefs (RR=2.86, 95%CI: 1.70–4.82) had a significantly higher prevalence of smoking. The results of this analysis suggest that a relationship may exist between human rights violations and smoking among South Africa adults. Future research should use longitudinal data to assess causality, test the generalizability of these findings, and consider how to apply these findings to smoking cessation interventions. PMID:24509050

  10. Continued transmission of Zika virus in humans in West Africa, 1992-2016.

    PubMed

    Herrera, Bobby Brooke; Chang, Charlotte A; Hamel, Donald J; Mboup, Souleymane; Ndiaye, Daouda; Imade, Godwin; Okpokwu, Jonathan; Agbaji, Oche; Bei, Amy K; Kanki, Phyllis J

    2017-04-08

    First identified in 1947 in Uganda, Zika virus (ZIKV) has remained largely unstudied until the recent outbreak in Latin America. This study aimed to measure the prevalence of ZIKV in febrile patients in Senegal and Nigeria in samples collected from 1992-2016. The seroprevalence of ZIKV was 6.2% based on ZIKV IgM and negative for dengue reactivity. ZIKV envelope (E) was amplified from 4 samples. Phylogenetic analysis showed that the ZIKVs belonged to the African lineage, grouping with either the Nigerian or MR766 sub-lineages. This study provides evidence that ZIKV has been silently circulating in West Africa for two decades.

  11. Acceptability of human papillomavirus vaccine: a survey among master of business administration students in KwaZulu-Natal, South Africa.

    PubMed

    Hoque, Muhammad Ehsanul; Van Hal, Guido

    2014-01-01

    Cervical cancer is a preventable public health problem. The two new human papillomavirus (HPV) vaccines are available but not accessible to everyone in South Africa, as they are very expensive. This study aimed to investigate educated peoples acceptability regarding HPV vaccination. This was a cross-sectional survey conducted among 146 master of business administration students by self-administered, anonymous questionnaire. The majority (74%) of the participants ever heard of cervical cancer, but only 26.2% heard about HPV. After reading the fact information regarding cervical cancer and HPV, the intention to vaccinate their daughters increased from 88% to 97.2% (P = 0.003). The majority (75.4%) indicated that HPV vaccination should be given before their daughters are mature enough to understand about sex, and 80.3% reported that they will discuss matters related to sex with their daughters if their daughters want to know about the vaccine. Those who did not want to vaccinate their daughters highlighted that they want more information regarding safety of the vaccine which might change their decision towards HPV vaccination. A health education information method can increase the vaccination acceptance rate in South Africa.

  12. Human placental lactogen decreases regional blood flow in anesthetized pigs.

    PubMed

    Grossini, E; Molinari, C; Battaglia, A; Mary, D A S G; Ribichini, F; Surico, N; Vacca, G

    2006-01-01

    In 22 pigs anesthetized with sodium pentobarbitone, changes in blood flow caused by infusion of human placental lactogen into the left renal, external iliac, and anterior descending coronary arteries were assessed using electromagnetic flowmeters. In 17 pigs, infusion of human placental lactogen whilst keeping the heart rate and arterial pressure constant decreased coronary, renal and iliac flow. In 5 additional pigs, increasing the dose of human placental lactogen produced a dose-related decrease in regional blood flow. The mechanisms of the above response were studied in 15 of the 17 pigs by repeating the experiment of infusion. The human placental lactogen-induced decrease in regional blood flow was not affected by blockade of cholinergic receptors (5 pigs) or of alpha-adrenergic receptors (5 pigs), but it was abolished by blockade of beta2-adrenergic receptors (5 pigs). The present study showed that intra-arterial infusion of human placental lactogen primarily decreased coronary, renal and iliac blood flow. The mechanism of this response was shown to be due to the inhibition of a vasodilatory beta2-adrenergic receptor-mediated effect.

  13. Potential for human immunodeficiency virus parenteral transmission in the Middle East and North Africa: An analysis using hepatitis C virus as a proxy biomarker

    PubMed Central

    Mohamoud, Yousra A; Miller, F DeWolfe; Abu-Raddad, Laith J

    2014-01-01

    The Middle East and North Africa (MENA) region has endured several major events of infection parenteral transmission. Recent work has established the utility of using hepatitis C virus (HCV) as a proxy biomarker for assessing the epidemic potential for human immunodeficiency virus (HIV) parenteral transmission. In this review, we use data on the prevalence of HCV infection antibody (seroprevalence) among general population and high risk population groups to assess the potential for HIV parenteral transmission in MENA. Relatively low prevalence of HCV infection in the general population groups was reported in most MENA countries indicating that parenteral HIV transmission at endemic levels does not appear to be a cause for concern. Nonetheless, there could be opportunities for localized HIV outbreaks and transmission of other blood-borne infections in some settings such as healthcare facilities. Though there have been steady improvements in safety measures related to parenteral modes of transmission in the region, these improvements have not been uniform across all countries. More precautions, including infection control training programs, surveillance systems for nosocomial infections and wider coverage and evaluation of hepatitis B virus immunization programs need to be implemented to avoid the unnecessary spread of HIV, HCV, and other blood-borne pathogens along the parenteral modes of transmission. PMID:25278675

  14. Multi-environment selection of small sieve snap beans reduces production constraints in East Africa and subtropical regions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Common bean rust caused by Uromyces appendiculatus, and heat stress lower the yield and quality of snap beans (Phaseolus vulgaris L.) in East Africa. Four snap bean breeding lines previously selected for broad-spectrum rust resistance (involving Ur-4 and Ur-11 rust genes) and heat tolerance followin...

  15. Defining minimum standards of practice for incorporating African traditional medicine into HIV/AIDS prevention, care, and support: a regional initiative in eastern and southern Africa.

    PubMed

    Homsy, Jaco; King, Rachel; Tenywa, Joseph; Kyeyune, Primrose; Opio, Alex; Balaba, Dorothy

    2004-10-01

    In many resource-poor settings of Africa, a majority of people living with HIV/AIDS depend on and choose traditional healers for psychosocial counseling and health care. If the current pan-African prevention and care efforts spurred by the HIV pandemic do not actively engage African Traditional Medicine, they will effectively miss 80%, the vast majority of the African people who, according to the World Health Organization, rely on traditional medicine for their primary health care needs. In 2001, the Ugandan nongovernmental organization, Traditional and Modern Health Practitioners Together Against AIDS and Other Diseases, in Kampala, identified the need for a concerted, systematic, and sustained effort at both local and regional levels to support and validate African Traditional Medicine on several fronts. The Eastern & Southern Africa Regional Initiative on Traditional Medicine and AIDS was borne out of this assessment. It convened a regional consultation in May 2003, which produced a series of proposed standards around six main themes related to traditional medicine and HIV/AIDS: the systematic evaluation of traditional remedies; spiritual aspects of healing; HIV prevention and care; processing and packaging of traditional remedies; protection of indigenous knowledge; and intellectual property rights related to traditional health systems. These standards, summarized in this paper, will be incorporated into programs on traditional medicine and HIV/AIDS by various implementers in the region. A number of strategies to test and implement these recommendations are also defined.

  16. West Africa

    NASA Technical Reports Server (NTRS)

    2002-01-01

    With its vast expanses of sand, framed by mountain ranges and exposed rock, northwestern Africa makes a pretty picture when viewed from above. This image was acquired by the Moderate-resolution Imaging Spectroradiometer (MODIS), flying aboard NASA's Terra spacecraft. The Canary Islands can be seen on the left side of the image just off Africa's Atlantic shore. The light brown expanse running through the northern two thirds of the image is the Sahara Desert. The desert runs up against the dark brown Haut Atlas mountain range of Morocco in the northwest, the Atlantic Ocean to the west and the semi-arid (light brown pixels) Sahelian region in the South. The Sahara, however, isn't staying put. Since the 1960s, the desert has been expanding into the Sahelian region at a rate of up to 6 kilometers per year. In the 1980s this desert expansion, combined with over cultivation of the Sahel, caused a major famine across west Africa. Over the summer months, strong winds pick up sands from the Sahara and blow them across the Atlantic as far west as North America, causing air pollution in Miami and damaging coral reefs in the Bahamas and the Florida Keys. The white outlines on the map represent country borders. Starting at the top-most portion of the map and working clockwise, the countries shown are Morocco, Western Sahara, Mauritania, Senegal, Mali, Burkina Fasso, Nigeria, Mali (again), and Algeria. Image by Reto Stockli, Robert Simmon, and Brian Montgomery, NASA Earth Observatory, based on data from MODIS

  17. Regional boreal biodiversity peaks at intermediate human disturbance.

    PubMed

    Mayor, S J; Cahill, J F; He, F; Sólymos, P; Boutin, S

    2012-01-01

    The worldwide biodiversity crisis has intensified the need to better understand how biodiversity and human disturbance are related. The 'intermediate disturbance hypothesis' suggests that disturbance regimes generate predictable non-linear patterns in species richness. Evidence often contradicts intermediate disturbance hypothesis at small scales, and is generally lacking at large regional scales. Here, we present the largest extent study of human impacts on boreal plant biodiversity to date. Disturbance extent ranged from 0 to 100% disturbed in vascular plant communities, varying from intact forest to agricultural fields, forestry cut blocks and oil sands. We show for the first time that across a broad region species richness peaked in communities with intermediate anthropogenic disturbance, as predicted by intermediate disturbance hypothesis, even when accounting for many environmental covariates. Intermediate disturbance hypothesis was consistently supported across trees, shrubs, forbs and grasses, with temporary and perpetual disturbances. However, only native species fit this pattern; exotic species richness increased linearly with disturbance.

  18. Regional Variations in Mechanical Strain in the Posterior Human Sclera

    PubMed Central

    Fazio, Massimo A.; Grytz, Rafael; Bruno, Luigi; Girard, Michael J. A.; Gardiner, Stuart; Girkin, Christopher A.; Downs, J. Crawford

    2012-01-01

    Purpose. The goal of this study was to establish sectorial and regional variability in the mechanical strain of peripapillary and mid-peripheral sclera in normal eyes from elderly human donors. Methods. Ten pairs of normal eyes from human donors aged 57 to 90 years old were mechanically inflation-tested within 48 hours post mortem. The intact posterior scleral shells were pressurized from 5 to 45 mm Hg while the full-field three-dimensional displacements of the scleral surface were measured using laser speckle interferometry. The displacement field was fit to continuous and differentiable analytical functions, from which the full strain tensor of the outer scleral surface was calculated. Mean maximum principal (tensile) strain was computed for eight circumferential sectors (45° wide) within the peripapillary and mid-peripheral regions surrounding the optic nerve head (ONH). Results. Overall, the peripapillary sclera exhibited significantly higher tensile strain (1.2%) than mid-peripheral sclera (0.95%) for a 40 mm Hg IOP elevation (P < 0.00001). In the peripapillary region, the inferotemporal sector exhibited the highest tensile strain (1.45%) while the superior sector had the lowest (1.19%; P < 0.00001). Mid-peripheral scleral strains were lower but exhibited a similar sectorial pattern. Conclusions. Human posterior sclera exhibits complex regional mechanical behavior in response to acute IOP elevations from 5 to 45 mm Hg. Results indicate 1) the peripapillary sclera is subjected to significantly higher tensile strain than the adjacent mid-peripheral sclera, and 2) strains are significantly higher in the temporal and inferior quadrants of the peripapillary sclera, which may contribute to the increased prevalence of glaucomatous damage associated with these regions of the ONH. PMID:22700704

  19. Small mammal utilization by Middle Stone Age humans at Die Kelders Cave 1 and Pinnacle Point Site 5-6, Western Cape Province, South Africa.

    PubMed

    Armstrong, Aaron

    2016-12-01

    Reported here are the results of a taphonomic analysis of the small mammals (between 0.75 kg and 4.5 kg adult body weight) and size 1 bovids (≤20 kg adult body weight) from the Middle Stone Age (MSA) sites of Die Kelders Cave 1 (DK1) and Pinnacle Point Site 5-6 (PP5-6), Western Cape Province, South Africa. This study provides a comprehensive taphonomic analysis of MSA small mammals with a focus on discerning the role of humans in their accumulation and the implications for human behavioral adaptations. Based on comparisons with control assemblages of known accumulation, it is evident that humans accumulated many of the Cape dune mole-rats, hares, and size 1 bovids at DK1. The patterning of cut-marked and burned mole-rat remains at DK1 provides evidence in the MSA for the systematic utilization of small mammals for their skins and as a protein source. Unlike DK1, small mammals and size 1 bovids constitute only a small portion of the PP5-6 mammals and they exhibit little evidence of human accumulation. Nocturnal and diurnal raptors accumulated most of the small fauna at PP5-6. The nominal presence of small mammals in the PP5-6 fauna is atypical of MSA sites in the Cape Floristic Region, where they are abundant and often constitute large portions of MSA archaeofaunas. DK1 humans maximized the environmental yield by exploiting low-quality resources, a strategy employed possibly in response to localized environmental conditions and to greater human population densities. In comparison, the MIS5-4 humans at PP5-6 did not exploit small mammals and instead focused on higher-quality resources like shellfish and large ungulates. Humans and predators accumulated few small mammals at PP5-6, suggesting that these taxa may have been less abundant near the site and/or that humans could afford to concentrate on high-quality resources, perhaps because of a higher-yield local environment. This study suggests that an adaptive response to the environmental conditions of MIS4 was

  20. Mutations in Human Accelerated Regions Disrupt Cognition and Social Behavior.

    PubMed

    Doan, Ryan N; Bae, Byoung-Il; Cubelos, Beatriz; Chang, Cindy; Hossain, Amer A; Al-Saad, Samira; Mukaddes, Nahit M; Oner, Ozgur; Al-Saffar, Muna; Balkhy, Soher; Gascon, Generoso G; Nieto, Marta; Walsh, Christopher A

    2016-10-06

    Comparative analyses have identified genomic regions potentially involved in human evolution but do not directly assess function. Human accelerated regions (HARs) represent conserved genomic loci with elevated divergence in humans. If some HARs regulate human-specific social and behavioral traits, then mutations would likely impact cognitive and social disorders. Strikingly, rare biallelic point mutations-identified by whole-genome and targeted "HAR-ome" sequencing-showed a significant excess in individuals with ASD whose parents share common ancestry compared to familial controls, suggesting a contribution in 5% of consanguineous ASD cases. Using chromatin interaction sequencing, massively parallel reporter assays (MPRA), and transgenic mice, we identified disease-linked, biallelic HAR mutations in active enhancers for CUX1, PTBP2, GPC4, CDKL5, and other genes implicated in neural function, ASD, or both. Our data provide genetic evidence that specific HARs are essential for normal development, consistent with suggestions that their evolutionary changes may have altered social and/or cognitive behavior. PAPERCLIP.

  1. Analysis of the PTCH coding region in human rhabdomyosarcoma.

    PubMed

    Calzada-Wack, Julia; Schnitzbauer, Udo; Walch, Axel; Wurster, Karl-Heinz; Kappler, Roland; Nathrath, Michaela; Hahn, Heidi

    2002-09-01

    Inherited mutations of the human tumor suppressor gene Patched (PTCH) lead to an autosomal dominant disorder known as Nevoid Basal Cell Carcinoma Syndrome (NBCCS). The syndrome is characterized by a combination of developmental abnormalities and a predisposition to tumor formation. Tumors in patients with NBCCS include basal cell carcinoma, medulloblastoma, fibroma and rhabdomyosarcoma (RMS). RMS are also present in 15 % of mice haplodeficient for Ptch. To investigate whether mutations in PTCH are a general feature in rhabdomyosarcomagenesis we sequenced the protein-coding region in sporadic human cases of these tumors. For this purpose we first determined the distribution and frequency of polymorphisms in 23 exons of PTCH in 48 healthy caucasians. Ten new polymorphisms were identified (IVS11 + 15-17del AAA; IVS14 + 25T>C; 2485G>A; IVS15 + 9G>C; IVS17 + 21A>G; 3033T>C; 3149T>C; 3387T>C; 3617G>A; 4080C>T). Next, the PTCH coding region in 14 RMS was sequenced. Whereas one case with LOH at the PTCH locus was detected, none of the cases showed nonsense or missense mutations in the coding region of PTCH. These data do not support the existence of frequent mutations in the protein-coding region of PTCH in RMS.

  2. Molecular characterization and second-line antituberculosis drug resistance patterns of multidrug-resistant Mycobacterium tuberculosis isolates from the northern region of South Africa.

    PubMed

    Said, Halima M; Kock, Marleen M; Ismail, Nazir A; Mphahlele, Matsie; Baba, Kamaldeen; Omar, Shaheed V; Osman, Ayman G; Hoosen, Anwar A; Ehlers, Marthie M

    2012-09-01

    Despite South Africa being one of the high-burden multidrug-resistant tuberculosis (MDR-TB) countries, information regarding the population structure of drug-resistant Mycobacterium tuberculosis strains is limited from many regions of South Africa. This study investigated the population structure and transmission patterns of drug-resistant M. tuberculosis isolates in a high-burden setting of South Africa as well as the possible association of genotypes with drug resistance and demographic characteristics. A total of 336 consecutive MDR-TB isolates from four provinces of South Africa were genotyped using spoligotyping and mycobacterial interspersed repetitive-unit-variable number tandem repeat (MIRU-VNTR) typing. Drug susceptibility testing for ofloxacin, kanamycin, and capreomycin was performed using the agar proportion method. The results showed that 4.8% of MDR-TB isolates were resistant to ofloxacin, 2.7% were resistant to kanamycin, and 4.5% were resistant to capreomycin, while 7.1% were extensively drug resistant (XDR), and the remaining 83.6% were susceptible to all of the second-line drugs tested. Spoligotyping grouped 90.8% of the isolates into 25 clusters, while 9.2% isolates were unclustered. Ninety-one percent of the 336 isolates were assigned to 21 previously described shared types, with the Beijing family being the predominant genotype in the North-West and Limpopo Provinces, while the EAI1_SOM family was the predominant genotype in the Gauteng and Mpumalanga Provinces. No association was found between genotypes and specific drug resistance patterns or demographic information. The high level of diversity and the geographical distribution of the drug-resistant M. tuberculosis isolates in this study suggest that the transmission of TB in the study settings is not caused by the clonal spread of a specific M. tuberculosis strain.

  3. Climate change projections for CORDEX-Africa with COSMO-CLM regional climate model and differences with the driving global climate models

    NASA Astrophysics Data System (ADS)

    Dosio, Alessandro; Panitz, Hans-Jürgen

    2016-03-01

    In the framework of the coordinated regional climate downscaling experiment (CORDEX), an ensemble of climate change projections for Africa has been created by downscaling the simulations of four global climate models (GCMs) by means of the consortium for small-scale modeling (COSMO) regional climate model (RCM) (COSMO-CLM, hereafter, CCLM). Differences between the projected temperature and precipitation simulated by CCLM and the driving GCMs are analyzed and discussed. The projected increase of seasonal temperature is found to be relatively similar between GCMs and RCM, although large differences (more than 1 °C) exist locally. Differences are also found for extreme-event related quantities, such as the spread of the upper end of the maximum temperature probability distribution function and, in turn, the duration of heat waves. Larger uncertainties are found in the future precipitation changes; this is partly a consequence of the inter-model (GCMs) variability over some areas (e.g. Sahel). However, over other regions (e.g. Central Africa) the rainfall trends simulated by CCLM and the GCMs show opposite signs, with CCLM showing a significant reduction in precipitation at the end of the century. This uncertain and sometimes contrasting behaviour is further investigated by analyzing the different models' response to the land-atmosphere interaction and feedback. Given the large uncertainty associated with inter-model variability across GCMs and the reduced spread in the results when a single RCM is used for downscaling, we strongly emphasize the importance of exploiting fully the CORDEX-Africa multi-GCM/multi-RCM ensemble in order to assess the robustness of the climate change signal and, possibly, to identify and quantify the many sources of uncertainty that still remain.

  4. Specific Regional Transcription of Apolipoprotein E in Human Brain Neurons

    PubMed Central

    Xu, Pu-Ting; Gilbert, John R.; Qiu, Hui-Ling; Ervin, John; Rothrock-Christian, Tracie R.; Hulette, Christine; Schmechel, Donald E.

    1999-01-01

    In central nervous system injury and disease, apolipoprotein E (APOE, gene; apoE, protein) might be involved in neuronal injury and death indirectly through extracellular effects and/or more directly through intracellular effects on neuronal metabolism. Although intracellular effects could clearly be mediated by neuronal uptake of extracellular apoE, recent experiments in injury models in normal rodents and in mice transgenic for the human APOE gene suggest the additional possibility of intraneuronal synthesis. To examine whether APOE might be synthesized by human neurons, we performed in situ hybridization on paraffin-embedded and frozen brain sections from three nondemented controls and five Alzheimer’s disease (AD) patients using digoxigenin-labeled antisense and sense cRNA probes to human APOE. Using the antisense APOE probes, we found the expected strong hybridization signal in glial cells as well as a generally fainter signal in selected neurons in cerebral cortex and hippocampus. In hippocampus, many APOE mRNA-containing neurons were observed in sectors CA1 to CA4 and the granule cell layer of the dentate gyrus. In these regions, APOE mRNA containing neurons could be observed adjacent to nonhybridizing neurons of the same cell class. APOE mRNA transcription in neurons is regionally specific. In cerebellar cortex, APOE mRNA was seen only in Bergmann glial cells and scattered astrocytes but not in Purkinje cells or granule cell neurons. ApoE immunocytochemical localization in semi-adjacent sections supported the selectivity of APOE transcription. These results demonstrate the expected result that APOE mRNA is transcribed and expressed in glial cells in human brain. The important new finding is that APOE mRNA is also transcribed and expressed in many neurons in frontal cortex and human hippocampus but not in neurons of cerebellar cortex from the same brains. This regionally specific human APOE gene expression suggests that synthesis of apoE might play a role

  5. Advancing human rights through constitutional protection for gays and lesbians in South Africa.

    PubMed

    Louw, Ronald

    2005-01-01

    As a consequence of the 1994 adoption of a justiciable Bill of Rights in South Africa, with an equality provision prohibiting discrimination on the ground of sexual orientation, a coalition of gay and lesbian organisations set about implementing a progressive agenda of gay and lesbian rights litigation. In striking down the offence of sodomy, the Constitutional Court established a jurisprudence of gay and lesbian rights to equality, dignity and privacy that proved to be the foundation for significant litigation around family law issues. Subsequent to the sodomy judgement, the Court has ruled that same-sex couples who are in permanent life partnerships should be entitled to the same rights as married couples to immigration, employment benefits, custody and adoption of children. Despite the extensive equality jurisprudence of the Court, it is still uncertain whether it will rule in the future in favour of same-sex marriage or in favour of a civil union/domestic partnership model.

  6. Flavin nucleotides in human lens: regional distribution in brunescent cataracts.

    PubMed

    Bhat, K S; Nayak, S

    1998-12-01

    The biochemical mechanism(s) underlying brunescent cataracts remain unclear. Oxidative stress due to reactive oxygen species may have a role in the pigmentation process in eye lens. We have analysed human cataractous lenses for flavins by high-performance liquid chromatography (HPLC), since flavins are light sensitive and act as endogenous sensitizers generating reactive oxygen species in the eye. The most significant observation in this study is that higher levels of flavin nucleotides occur in brown lens compared to yellow lens. The concentration of flavin nucleotides (flavin monouncleotide, FMN + flavin adenine dinucleotide, FAD) was highest in the nuclear region of the lens followed by the cortical and capsule-epithelial regions. However, the ratio of FAD/FMN was lowest in the nuclear region of the lens followed by other regions. On the other hand, riboflavin was not detected in any of the lens (cataractous) regions. These results suggest that the observed increase in flavin nucleotides in the ocular tissue could contribute towards deepening of lens pigmentation.

  7. Leptospira Serovars for Diagnosis of Leptospirosis in Humans and Animals in Africa: Common Leptospira Isolates and Reservoir Hosts

    PubMed Central

    Mgode, Georgies F.; Machang’u, Robert S.; Mhamphi, Ginethon G.; Katakweba, Abdul; Mulungu, Loth S.; Durnez, Lies; Leirs, Herwig; Hartskeerl, Rudy A.; Belmain, Steven R.

    2015-01-01

    The burden of leptospirosis in humans and animals in Africa is higher than that reported from other parts of the world. However, the disease is not routinely diagnosed in the continent. One of major factors limiting diagnosis is the poor availability of live isolates of locally circulating Leptospira serovars for inclusion in the antigen panel of the gold standard microscopic agglutination test (MAT) for detecting antibodies against leptospirosis. To gain insight in Leptospira serovars and their natural hosts occurring in Tanzania, concomitantly enabling the improvement of the MAT by inclusion of fresh local isolates, a total of 52 Leptospira isolates were obtained from fresh urine and kidney homogenates, collected between 1996 and 2006 from small mammals, cattle and pigs. Isolates were identified by serogrouping, cross agglutination absorption test (CAAT), and molecular typing. Common Leptospira serovars with their respective animal hosts were: Sokoine (cattle and rodents); Kenya (rodents and shrews); Mwogolo (rodents); Lora (rodents); Qunjian (rodent); serogroup Grippotyphosa (cattle); and an unknown serogroup from pigs. Inclusion of local serovars particularly serovar Sokoine in MAT revealed a 10-fold increase in leptospirosis prevalence in Tanzania from 1.9% to 16.9% in rodents and 0.26% to 10.75% in humans. This indicates that local serovars are useful for diagnosis of human and animal leptospirosis in Tanzania and other African countries. PMID:26624890

  8. Chromosome region-specific libraries for human genome analysis

    SciTech Connect

    Kao, Fa-Ten.

    1991-01-01

    We have made important progress since the beginning of the current grant year. We have further developed the microdissection and PCR- assisted microcloning techniques using the linker-adaptor method. We have critically evaluated the microdissection libraries constructed by this microtechnology and proved that they are of high quality. We further demonstrated that these microdissection clones are useful in identifying corresponding YAC clones for a thousand-fold expansion of the genomic coverage and for contig construction. We are also improving the technique of cloning the dissected fragments in test tube by the TDT method. We are applying both of these PCR cloning technique to human chromosomes 2 and 5 to construct region-specific libraries for physical mapping purposes of LLNL and LANL. Finally, we are exploring efficient procedures to use unique sequence microclones to isolate cDNA clones from defined chromosomal regions as valuable resources for identifying expressed gene sequences in the human genome. We believe that we are making important progress under the auspices of this DOE human genome program grant and we will continue to make significant contributions in the coming year. 4 refs., 4 figs.

  9. Secondary Education in Africa: Strategies for Renewal. World Bank Presentations at the UNESCO/BREDA-World Bank Regional Workshop on the Renewal of Secondary Education in Africa (Mauritius, Africa, December 2001). Africa Region Human Development Working Paper Series.

    ERIC Educational Resources Information Center

    Mastri, Lawrence, Ed.

    During the last 3 decades secondary education has become universal in most industrialized countries. Sub-Saharan African countries face special challenges to benefit from this international trend. The gap between these countries and the rest of the world in coverage, quality, and relevance of secondary education is widening. To address these…

  10. Pilot social feasibility study for the establishment of a public human umbilical cord blood stem cell bank in South Africa.

    PubMed

    Meissner-Roloff, Madelein; Young, Wendy; Rangaka, Isabella; Lombaard, Hennie; Dhai, Ames; Tsotsi, Norma; Pepper, Michael S

    2012-12-01

    There is a large unmet need in South Africa for bone marrow transplantation. Umbilical cord blood (UCB) is an important source of stem cells for the treatment of haematological and non-haematological diseases. Access to the two existing private umbilical cord blood stem cell banks (UCB SCBs) in South Africa is limited to individuals that can afford it, which further aggravates the ever increasing divide between families from different socio-economic classes. The problem is compounded by a severe global shortage of genetically compatible samples, representative of the South African demographics. Establishing a public human UCB SCB in South Africa would provide more South Africans with access to previously unavailable treatment in the form of affordable, genetically compatible stem cells for bone marrow transplantation. A public UCB SCB has many facets to consider, one of which is public preparedness and support for the bank. This was assessed in a social feasibility pilot study which is reported here. In addition to the findings of this social feasibility study, other important considerations for establishing a public human UCB SCB in SA include; (a) testing the samples for HIV and other infectious diseases (required for compliance with international regulatory standards); (b) flow cytometric analysis for enumeration of CD34+ UCB stem cells; (c) mapping of HLA genotypes/alleles; and (d) a study of the economic feasibility of this endeavour.The social feasibility study was conducted to gauge public preparedness and support for a public SCB through patient interviews and questionnaires. The process was dynamic due to its novel nature for interviewers and interviewees alike. Many obstacles were met and dealt with which lead to the compilation of results discussed here in the form of a pilot social feasibility study.In the South African context, we are faced with unique and rich challenges relating to cultural and religious differences that are further augmented by

  11. Mapping SLCO1B1 Genetic Variation for Global Precision Medicine in Understudied Regions in Africa: A Focus on Zulu and Cape Admixed Populations.

    PubMed

    Hoosain, Nisreen; Pearce, Brendon; Jacobs, Clifford; Benjeddou, Mongi

    2016-09-01

    The U.S. President Barack Obama has announced, in his State of the Union address on January 20, 2015, the Precision Medicine Initiative, a US$215-million program. For global precision medicine to become a reality, however, biological and environmental "variome" in previously understudied populations ought to be mapped and catalogued. Chief among the molecular targets that warrant global mapping is the organic anion-transporting polypeptide 1B1 (OATP1B1), encoded by solute carrier organic anion transporter family member 1B1 (SLCO1B1), a hepatic uptake transporter predominantly expressed in the basolateral side of hepatocytes. Human OATP1B1 plays a crucial role in the transport of a wide variety of substrates. This includes endogenous compounds such as bile salts as well as medicines, including benzylpenicillin, methotrexate, pravastatin, and rifampicin, and natural toxins microcystin and phalloidin. Genetic variations observed in the SLCO1B1 gene have been associated with altered in vitro and in vivo OATP1B1 transport activity, and consequently influencing patients' response to medicines, toxins, and susceptibility to common complex diseases. Well-characterized haplotypes, *5 (RS4149056C) and *15 (RS4149056T), have been associated with a strikingly reduced uptake of multiple OATP1B1 substrates, including estrone-3-sulfate, estradiol-17β-d-glucuronide, atorvastatin, cerivastatin, pravastatin, and rifampicin. In particular, RS4149056C is observed in 60% of the Cape admixed (CA) population and is associated with increased plasma concentrations of many statins as well as fexofenadine and repaglinide. We designed and optimized a SNaPshot minisequencing panel to characterize the variants of relevance for precision medicine in the clinic. We report here the first study on allele and genotype frequencies for 10 nonsynonymous, 4 synonymous, and 6 intronic single-nucleotide polymorphisms of SLCO1B1 in the Zulu and CA populations of South Africa. These variants are further

  12. Diagnosis and predictive molecular analysis of non-small-cell lung cancer in the Africa-Middle East region: challenges and strategies for improvement.

    PubMed

    Slavik, Tomas; Asselah, Fatima; Fakhruddin, Najla; El Khodary, Ahmed; Torjman, Fairouz; Anis, Elia; Quinn, Martin; Khankan, Azzam; Kerr, Keith M

    2014-11-01

    The identification of tumor biomarkers provides information on the prognosis and guides the implementation of appropriate treatment in patients with many different cancer types. In non-small cell lung cancer (NSCLC), targeted treatment plans based on biomarker identification have already been used in the clinic. However, such predictive molecular testing is not currently a universally used practice. This is the case, in particular, in developing countries where lung cancer is increasingly prevalent. In September 2012 and November 2013, a committee of 16 lung cancer experts from Africa and the Middle East met to discuss key issues related to diagnosis and biomarker testing in NSCLC and the implementation of personalized medicine in the region. The committee identified current challenges for effective diagnosis and predictive analysis in Africa and the Middle East. Moreover, strategies to encourage the implementation of biomarker testing were discussed. A practical approach for the effective diagnosis and predictive molecular testing of NSCLC in these regions was derived. We present the key issues and recommendations arising from the meetings.

  13. Beyond the rhetoric: towards a more effective and humane drug policy framework in South Africa.

    PubMed

    Parry, Charles; Myers, Bronwyn

    2011-10-01

    The March 2011 Anti-Substance Summit in Durban continued the outdated approach to policy around illicit drugs in South Africa. It missed opportunities for discussing how to impact significantly on the health and social harms associated with problematic drug use and reduce the burden of drug-related cases in the criminal justice system. The government needs to move away from the political rhetoric of a 'drug-free society' and start the real work of formulating and implementing an evidence-based drug policy that learns from the experiences of other countries around decriminalising drug use; takes into account differences in the harms resulting from different classes of drug; adopts a rights-based, public health approach to policy; and identifies a single (accountable) agency that has the authority to oversee policy implementation. In addition, consensus is needed on he short-, medium- and long -term priorities for drug policy strategies identified by Babor et al. may serve as a useful starting point for policy development.

  14. Human factors facilitating the spread of a parasitic honey bee in South Africa.

    PubMed

    Dietemann, Vincent; Lubbe, Annelize; Crewe, Robin M

    2006-02-01

    Workers of the honey bee subspecies Apis mellifera capensis (Eschscholtz) produce female offspring by thelytokous parthenogenesis and can parasitize colonies of other subspecies. In 1990, translocation of 400 colonies of A. m. capensis into the distribution area of A. m. scutellata by a commercial beekeeper triggered a dramatic parasitic phenomenon. Parasitized colonies died within a few months of infestation, and this resulted in the loss of tens of thousands of colonies by commercial beekeepers in the A. m. scutellata range in South Africa. To deal with the problem and to identify methods that would limit the impact of the social parasite, we investigated the link between beekeeping management and severity of parasitic infestations in terms of colony mortality and productivity. We demonstrate that colonies from apiaries subjected to migrations are very susceptible to infestation and consequently show dramatic mortality. Their productivity is also inferior to sedentary colonies and those in isolated apiaries in terms of honey yield and brood quantity. Furthermore, by concentrating hives in small areas and often in the vicinity of other beekeepers, cross-infestations can easily occur. This can undermine previously parasite-free beekeeping businesses. As a result of our surveys, we propose beekeeping practices based on locally trapped bees, reduced migration, and better control of parasite spread, thus promoting the conservation of these pollinators. If followed by all the South African beekeepers, these measures should limit the spread of the parasite until it is eliminated within a few years, after which full migratory beekeeping practices could resume.

  15. Climatic, socio-economic, and health factors affecting human vulnerability to cholera in the Lake Victoria basin, East Africa.

    PubMed

    Olago, Daniel; Marshall, Michael; Wandiga, Shem O; Opondo, Maggie; Yanda, Pius Z; Kanalawe, Richard; Githeko, Andrew K; Downs, Tim; Opere, Alfred; Kavumvuli, Robert; Kirumira, Edward; Ogallo, Laban; Mugambi, Paul; Apindi, Eugene; Githui, Faith; Kathuri, James; Olaka, Lydia; Sigalla, Rehema; Nanyunja, Robinah; Baguma, Timothy; Achola, Pius

    2007-06-01

    Cholera epidemics have a recorded history in the eastern Africa region dating to 1836. Cholera is now endemic in the Lake Victoria basin, a region with one of the poorest and fastest growing populations in the world. Analyses of precipitation, temperatures, and hydrological characteristics of selected stations in the Lake Victoria basin show that cholera epidemics are closely associated with El Niño years. Similarly, sustained temperatures high above normal (T(max)) in two consecutive seasons, followed by a slight cooling in the second season, trigger an outbreak of a cholera epidemic. The health and socioeconomic systems that the lake basin communities rely upon are not robust enough to cope with cholera outbreaks, thus rendering them vulnerable to the impact of climate variability and change. Collectively, this report argues that communities living around the Lake Victoria basin are vulnerable to climate-induced cholera that is aggravated by the low socioeconomic status and lack of an adequate health care system. In assessing the communities' adaptive capacity, the report concludes that persistent levels of poverty have made these communities vulnerable to cholera epidemics.

  16. An overview of regional and local characteristics of aerosols in South Africa using satellite, ground, and modeling data

    PubMed Central

    Hersey, S. P.; Garland, R. M.; Crosbie, E.; Shingler, T.; Sorooshian, A.; Piketh, S.; Burger, R.

    2015-01-01

    We present a comprehensive overview of particulate air quality across the five major metropolitan areas of South Africa (Cape Town, Bloemfontein, Johannesburg and Tshwane (Gauteng Province), the Industrial Highveld Air Quality Priority Area (HVAPA), and Durban), based on a decadal (1 January 2000 to 31 December 2009) aerosol climatology from multiple satellite platforms and detailed analysis of ground-based data from 19 sites throughout Gauteng Province. Satellite analysis was based on aerosol optical depth (AOD) from MODIS Aqua and Terra (550 nm) and MISR (555 nm) platforms, Ångström Exponent (α) from MODIS Aqua (550/865 nm) and Terra (470/660 nm), ultraviolet aerosol index (UVAI) from TOMS, and results from the Goddard Ozone Chemistry Aerosol Radiation and Transport (GOCART) model. At continentally influenced sites, AOD, α, and UVAI reach maxima (0.12–0.20, 1.0–1.8, and 1.0–1.2, respectively) during austral spring (September–October), coinciding with a period of enhanced dust generation and the maximum integrated intensity of close-proximity and subtropical fires identified by MODIS Fire Information for Resource Management System (FIRMS). Minima in AOD, α, and UVAI occur during winter. Results from ground monitoring indicate that low-income township sites experience by far the worst particulate air quality in South Africa, with seasonally averaged PM10 concentrations as much as 136 % higher in townships that in industrial areas. We report poor agreement between satellite and ground aerosol measurements, with maximum surface aerosol concentrations coinciding with minima in AOD, α, and UVAI. This result suggests that remotely sensed data are not an appropriate surrogate for ground air quality in metropolitan South Africa. PMID:26312061

  17. An overview of regional and local characteristics of aerosols in South Africa using satellite, ground, and modeling data

    NASA Astrophysics Data System (ADS)

    Hersey, S. P.; Garland, R. M.; Crosbie, E.; Shingler, T.; Sorooshian, A.; Piketh, S.; Burger, R.

    2015-04-01

    We present a comprehensive overview of particulate air quality across the five major metropolitan areas of South Africa (Cape Town, Bloemfontein, Johannesburg and Tshwane (Gauteng Province), the Industrial Highveld Air Quality Priority Area (HVAPA), and Durban), based on a decadal (1 January 2000 to 31 December 2009) aerosol climatology from multiple satellite platforms and detailed analysis of ground-based data from 19 sites throughout Gauteng Province. Satellite analysis was based on aerosol optical depth (AOD) from MODIS Aqua and Terra (550 nm) and MISR (555 nm) platforms, Ångström Exponent (α) from MODIS Aqua (550/865 nm) and Terra (470/660 nm), ultraviolet aerosol index (UVAI) from TOMS, and results from the Goddard Ozone Chemistry Aerosol Radiation and Transport (GOCART) model. At continentally influenced sites, AOD, α, and UVAI reach maxima (0.12-0.20, 1.0-1.8, and 1.0-1.2, respectively) during austral spring (September-October), coinciding with a period of enhanced dust generation and the maximum integrated intensity of close-proximity and subtropical fires identified by MODIS Fire Information for Resource Management System (FIRMS). Minima in AOD, α, and UVAI occur during winter. Results from ground monitoring indicate that low-income township sites experience by far the worst particulate air quality in South Africa, with seasonally averaged PM10 concentrations as much as 136% higher in townships that in industrial areas. We report poor agreement between satellite and ground aerosol measurements, with maximum surface aerosol concentrations coinciding with minima in AOD, α, and UVAI. This result suggests that remotely sensed data are not an appropriate surrogate for ground air quality in metropolitan South Africa.

  18. An overview of regional and local characteristics of aerosols in South Africa using satellite, ground, and modeling data.

    PubMed

    Hersey, S P; Garland, R M; Crosbie, E; Shingler, T; Sorooshian, A; Piketh, S; Burger, R

    We present a comprehensive overview of particulate air quality across the five major metropolitan areas of South Africa (Cape Town, Bloemfontein, Johannesburg and Tshwane (Gauteng Province), the Industrial Highveld Air Quality Priority Area (HVAPA), and Durban), based on a decadal (1 January 2000 to 31 December 2009) aerosol climatology from multiple satellite platforms and detailed analysis of ground-based data from 19 sites throughout Gauteng Province. Satellite analysis was based on aerosol optical depth (AOD) from MODIS Aqua and Terra (550 nm) and MISR (555 nm) platforms, Ångström Exponent (α) from MODIS Aqua (550/865 nm) and Terra (470/660 nm), ultraviolet aerosol index (UVAI) from TOMS, and results from the Goddard Ozone Chemistry Aerosol Radiation and Transport (GOCART) model. At continentally influenced sites, AOD, α, and UVAI reach maxima (0.12-0.20, 1.0-1.8, and 1.0-1.2, respectively) during austral spring (September-October), coinciding with a period of enhanced dust generation and the maximum integrated intensity of close-proximity and subtropical fires identified by MODIS Fire Information for Resource Management System (FIRMS). Minima in AOD, α, and UVAI occur during winter. Results from ground monitoring indicate that low-income township sites experience by far the worst particulate air quality in South Africa, with seasonally averaged PM10 concentrations as much as 136 % higher in townships that in industrial areas. We report poor agreement between satellite and ground aerosol measurements, with maximum surface aerosol concentrations coinciding with minima in AOD, α, and UVAI. This result suggests that remotely sensed data are not an appropriate surrogate for ground air quality in metropolitan South Africa.

  19. Human Rights Violations among Men Who Have Sex with Men in Southern Africa: Comparisons between Legal Contexts.

    PubMed

    Zahn, Ryan; Grosso, Ashley; Scheibe, Andrew; Bekker, Linda-Gail; Ketende, Sosthenes; Dausab, Friedel; Iipinge, Scholastica; Beyrer, Chris; Trapance, Gift; Baral, Stefan

    2016-01-01

    In 1994, South Africa approved a constitution providing freedom from discrimination based on sexual orientation. Other Southern African countries, including Botswana, Malawi, and Namibia, criminalize same-sex behavior. Men who have sex with men (MSM) have been shown to experience high levels of stigma and discrimination, increasing their vulnerability to negative health and other outcomes. This paper examines the relationship between criminalization of same-sex behavior and experiences of human rights abuses by MSM. It compares the extent to which MSM in peri-urban Cape Town experience human rights abuses with that of MSM in Gaborone, Botswana; Blantyre and Lilongwe, Malawi; and Windhoek, Namibia. In 2008, 737 MSM participated in a cross-sectional study using a structured survey collecting data regarding demographics, human rights, HIV status, and risk behavior. Participants accrued in each site were compared using bivariate and multivariate logistic regression. Encouragingly, the results indicate MSM in Cape Town were more likely to disclose their sexual orientation to family or healthcare workers and less likely to be blackmailed or feel afraid in their communities than MSM in Botswana, Malawi, or Namibia. However, South African MSM were not statistically significantly less likely experience a human rights abuse than their peers in cities in other study countries, showing that while legal protections may reduce experiences of certain abuses, legislative changes alone are insufficient for protecting MSM. A comprehensive approach with interventions at multiple levels in multiple sectors is needed to create the legal and social change necessary to address attitudes, discrimination, and violence affecting MSM.

  20. Distribution of a community of mammals in relation to roads and other human disturbances in Gabon, central Africa.

    PubMed

    Vanthomme, Hadrien; Kolowski, Joseph; Korte, Lisa; Alonso, Alfonso

    2013-04-01

    We present the first community-level study of the associations of both roads and other human disturbances with the distribution of mammals in Gabon (central Africa). Our study site was in an oil concession within a littoral mosaic landscape. We conducted surveys along 199 line transects and installed camera traps on 99 of these transects to document mammal presence and abundance. We used generalized linear mixed-effect models to document associations between variables related to the ecosystem (land cover, topography, and hydrology), roads (coating, width of rights of way, condition, type of vehicle used on the road, traffic level, affiliation of users, and general type of road), and other human disturbances (urbanization, agriculture, hunting, logging, gathering, and industrial activities) and the abundance or presence of 17 species or groups of mammals including elephant (Loxodonta cyclotis), buffalo (Syncerus caffer), sitatunga (Tragelaphus spekei), red river hog (Potamochoerus porcus), smaller ungulates, gorilla (Gorilla gorilla), chimpanzee (Pan troglodytes), side-striped jackal (Canis adustus), carnivores, monkeys, and large rodents. Some types of roads and other human disturbances were negatively associated with the abundance or presence of elephants, buffalos, gorillas, sitatungas, some monkeys, and duikers. The pattern of associations of mammals with roads and other human disturbances was diverse and included positive associations with road presence (red river hog, some monkeys, and duikers), agriculture (sitatunga, small carnivores, and large rodents) and industrial activities (sitatunga, red river hog, red duikers, and side-striped jackal). Our results suggest that the community of mammals we studied was mostly affected by hunting, agriculture, and urbanization, which are facilitated by road presence. We recommend increased regulation of agriculture, hunting, and road building in the area.

  1. Human Rights Violations among Men Who Have Sex with Men in Southern Africa: Comparisons between Legal Contexts

    PubMed Central

    Zahn, Ryan; Grosso, Ashley; Scheibe, Andrew; Bekker, Linda-Gail; Ketende, Sosthenes; Dausab, Friedel; Iipinge, Scholastica; Beyrer, Chris; Trapance, Gift; Baral, Stefan

    2016-01-01

    In 1994, South Africa approved a constitution providing freedom from discrimination based on sexual orientation. Other Southern African countries, including Botswana, Malawi, and Namibia, criminalize same-sex behavior. Men who have sex with men (MSM) have been shown to experience high levels of stigma and discrimination, increasing their vulnerability to negative health and other outcomes. This paper examines the relationship between criminalization of same-sex behavior and experiences of human rights abuses by MSM. It compares the extent to which MSM in peri-urban Cape Town experience human rights abuses with that of MSM in Gaborone, Botswana; Blantyre and Lilongwe, Malawi; and Windhoek, Namibia. In 2008, 737 MSM participated in a cross-sectional study using a structured survey collecting data regarding demographics, human rights, HIV status, and risk behavior. Participants accrued in each site were compared using bivariate and multivariate logistic regression. Encouragingly, the results indicate MSM in Cape Town were more likely to disclose their sexual orientation to family or healthcare workers and less likely to be blackmailed or feel afraid in their communities than MSM in Botswana, Malawi, or Namibia. However, South African MSM were not statistically significantly less likely experience a human rights abuse than their peers in cities in other study countries, showing that while legal protections may reduce experiences of certain abuses, legislative changes alone are insufficient for protecting MSM. A comprehensive approach with interventions at multiple levels in multiple sectors is needed to create the legal and social change necessary to address attitudes, discrimination, and violence affecting MSM. PMID:26764467

  2. High prevalence of Rickettsia africae variants in Amblyomma variegatum ticks from domestic mammals in rural western Kenya: implications for human health.

    PubMed

    Maina, Alice N; Jiang, Ju; Omulo, Sylvia A; Cutler, Sally J; Ade, Fredrick; Ogola, Eric; Feikin, Daniel R; Njenga, M Kariuki; Cleaveland, Sarah; Mpoke, Solomon; Ng'ang'a, Zipporah; Breiman, Robert F; Knobel, Darryn L; Richards, Allen L

    2014-10-01

    Tick-borne spotted fever group (SFG) rickettsioses are emerging human diseases caused by obligate intracellular Gram-negative bacteria of the genus Rickettsia. Despite being important causes of systemic febrile illnesses in travelers returning from sub-Saharan Africa, little is known about the reservoir hosts of these pathogens. We conducted surveys for rickettsiae in domestic animals and ticks in a rural setting in western Kenya. Of the 100 serum specimens tested from each species of domestic ruminant 43% of goats, 23% of sheep, and 1% of cattle had immunoglobulin G (IgG) antibodies to the SFG rickettsiae. None of these sera were positive for IgG against typhus group rickettsiae. We detected Rickettsia africae-genotype DNA in 92.6% of adult Amblyomma variegatum ticks collected from domestic ruminants, but found no evidence of the pathogen in blood specimens from cattle, goats, or sheep. Sequencing of a subset of 21 rickettsia-positive ticks revealed R. africae variants in 95.2% (20/21) of ticks tested. Our findings show a high prevalence of R. africae variants in A. variegatum ticks in western Kenya, which may represent a low disease risk for humans. This may provide a possible explanation for the lack of African tick-bite fever cases among febrile patients in Kenya.

  3. Identification of fibrillogenic regions in human triosephosphate isomerase

    PubMed Central

    Carcamo-Noriega, Edson N.

    2016-01-01

    Background. Amyloid secondary structure relies on the intermolecular assembly of polypeptide chains through main-chain interaction. According to this, all proteins have the potential to form amyloid structure, nevertheless, in nature only few proteins aggregate into toxic or functional amyloids. Structural characteristics differ greatly among amyloid proteins reported, so it has been difficult to link the fibrillogenic propensity with structural topology. However, there are ubiquitous topologies not represented in the amyloidome that could be considered as amyloid-resistant attributable to structural features, such is the case of TIM barrel topology. Methods. This work was aimed to study the fibrillogenic propensity of human triosephosphate isomerase (HsTPI) as a model of TIM barrels. In order to do so, aggregation of HsTPI was evaluated under native-like and destabilizing conditions. Fibrillogenic regions were identified by bioinformatics approaches, protein fragmentation and peptide aggregation. Results. We identified four fibrillogenic regions in the HsTPI corresponding to the β3, β6, β7 y α8 of the TIM barrel. From these, the β3-strand region (residues 59–66) was highly fibrillogenic. In aggregation assays, HsTPI under native-like conditions led to amorphous assemblies while under partially denaturing conditions (urea 3.2 M) formed more structured aggregates. This slightly structured aggregates exhibited residual cross-β structure, as demonstrated by the recognition of the WO1 antibody and ATR-FTIR analysis. Discussion. Despite the fibrillogenic regions present in HsTPI, the enzyme maintained under native-favoring conditions displayed low fibrillogenic propensity. This amyloid-resistance can be attributed to the three-dimensional arrangement of the protein, where β-strands, susceptible to aggregation, are protected in the core of the molecule. Destabilization of the protein structure may expose inner regions promoting β-aggregation, as well as the

  4. Experience and challenges for biologic use in the treatment of moderate-to-severe psoriasis in Africa and the Middle East region.

    PubMed

    Al Hammadi, Anwar; Al-Sheikh, Afaf; Ammoury, Alfred; Ghosn, Samer; Gisondi, Paolo; Hamadah, Issam; Kibbi, Abdul-Ghani; Shirazy, Khalid

    2017-03-01

    The incidence of psoriasis in Africa and the Middle East (AfME) is high as in other regions and represents a significant problem for both dermatologists and patients. Psoriasis co-morbidities such as obesity, cardiovascular disease and psoriatic arthritis (PsA) are also particularly common in these regions and may be under-recognized and under-treated. Despite this, regional guidelines to aid physicians on the appropriate use of biologic agents in their clinical practice are limited. A group of expert dermatologists from across the AfME region were surveyed to help establish best practice across the region, alongside supporting data from the literature. Although biologics have significantly improved patient outcomes since their introduction, the results of this survey identified several unmet needs, including the lack of consensus regarding their use in clinical practice. Discrepancy also exists among AfME physicians concerning the clinical relevance of immunogenicity to biologics, despite increasing data across inflammatory diseases. Significant treatment and management of challenges for psoriasis patients remain, and a move towards individualized, tailored care may help to address these issues. The development of specific local guidelines for the treatment of both psoriasis and PsA could also be a step towards understanding the distinct patient profiles in these regions.

  5. On the development of a coupled regional climate-vegetation model RCM-CLM-CN-DV and its validation in Tropical Africa

    NASA Astrophysics Data System (ADS)

    Wang, Guiling; Yu, Miao; Pal, Jeremy S.; Mei, Rui; Bonan, Gordon B.; Levis, Samuel; Thornton, Peter E.

    2016-01-01

    This paper presents a regional climate system model RCM-CLM-CN-DV and its validation over Tropical Africa. The model development involves the initial coupling between the ICTP regional climate model RegCM4.3.4 (RCM) and the Community Land Model version 4 (CLM4) including models of carbon-nitrogen dynamics (CN) and vegetation dynamics (DV), and further improvements of the models. Model improvements derive from the new parameterization from CLM4.5 that addresses the well documented overestimation of gross primary production (GPP), a refinement of stress deciduous phenology scheme in CN that addresses a spurious LAI fluctuation for drought-deciduous plants, and the incorporation of a survival rule into the DV model to prevent tropical broadleaf evergreens trees from growing in areas with a prolonged drought season. The impact of the modifications on model results is documented based on numerical experiments using various subcomponents of the model. The performance of the coupled model is then validated against observational data based on three configurations with increasing capacity: RCM-CLM with prescribed leaf area index and fractional coverage of different plant functional types (PFTs); RCM-CLM-CN with prescribed PFTs coverage but prognostic plant phenology; RCM-CLM-CN-DV in which both the plant phenology and PFTs coverage are simulated by the model. Results from these three models are compared against the FLUXNET up-scaled GPP and ET data, LAI and PFT coverages from remote sensing data including MODIS and GIMMS, University of Delaware precipitation and temperature data, and surface radiation data from MVIRI and SRB. Our results indicate that the models perform well in reproducing the physical climate and surface radiative budgets in the domain of interest. However, PFTs coverage is significantly underestimated by the model over arid and semi-arid regions of Tropical Africa, caused by an underestimation of LAI in these regions by the CN model that gets exacerbated

  6. Multilocus phylogeography of a widespread savanna-woodland-adapted rodent reveals the influence of Pleistocene geomorphology and climate change in Africa's Zambezi region.

    PubMed

    McDonough, Molly M; Šumbera, Radim; Mazoch, Vladimír; Ferguson, Adam W; Phillips, Caleb D; Bryja, Josef

    2015-10-01

    Understanding historical influences of climate and physiographic barriers in shaping patterns of biodiversity remains limited for many regions of the world. For mammals of continental Africa, phylogeographic studies, particularly for West African lineages, implicate both geographic barriers and climate oscillations in shaping small mammal diversity. In contrast, studies for southern African species have revealed conflicting phylogenetic patterns for how mammalian lineages respond to both climate change and geologic events such as river formation, especially during the Pleistocene. However, these studies were often biased by limited geographic sampling or exclusively focused on large-bodied taxa. We exploited the broad southern African distribution of a savanna-woodland-adapted African rodent, Gerbilliscus leucogaster (bushveld gerbil) and generated mitochondrial, autosomal and sex chromosome data to quantify regional signatures of climatic and vicariant biogeographic phenomena. Results indicate the most recent common ancestor for all G. leucogaster lineages occurred during the early Pleistocene. We documented six divergent mitochondrial lineages that diverged ~0.270-0.100 mya, each of which was geographically isolated during periods characterized by alterations to the course of the Zambezi River and its tributaries as well as regional 'megadroughts'. Results demonstrate the presence of a widespread lineage exhibiting demographic expansion ~0.065-0.035 mya, a time that coincides with savanna-woodland expansion across southern Africa. A multilocus autosomal perspective revealed the influence of the Kafue River as a current barrier to gene flow and regions of secondary contact among divergent mitochondrial lineages. Our results demonstrate the importance of both climatic fluctuations and physiographic vicariance in shaping the distribution of southern African biodiversity.

  7. Chronic obstructive pulmonary disease in the adult population within the Middle East and North Africa region: rationale and design of the BREATHE study.

    PubMed

    El Hasnaoui, Abdelkader; Rashid, Nauman; Lahlou, Aicha; Salhi, Hocine; Doble, Adam; Nejjari, Chakib

    2012-12-01

    The objective of the BREATHE study was to estimate the regional prevalence of chronic obstructive pulmonary disease (COPD) symptoms within the general population in the Middle East/North Africa (MENA) region and to document risk factors, disease characteristics and management using a standardised methodology. This was an observational population-based survey performed in ten countries in the Middle East and North Africa (Algeria, Egypt, Jordan, Lebanon, Morocco, Saudi Arabia, Syria, Tunisia, Turkey and United Arab Emirates), together with Pakistan. A general population sample of 10,000 subjects ≥ 40 years of age in each country or zone was generated from random telephone numbers. Structured interviews were proposed by telephone. A screening questionnaire was administered to each subject collecting information on respiratory symptoms and smoking habits. Subjects with chronic bronchitis or breathlessness and smoking ≥ 10 pack · years fulfilled the epidemiological definition of COPD ("COPD" population). This population then completed a full disease questionnaire, the COPD Assessment Test (CAT) and a cost-of-disease questionnaire. A randomly selected sample was also assessed by spirometry. In all, 457,258 telephone numbers were generated and contact was established with 210,121 subjects, of whom 65,154 were eligible and 62,086 accepted to participate. The overall response rate was 74.2%. 2,187 (3.5%) subjects fulfilled the criteria for the "COPD" population. Evaluable spirometry data were obtained from 1,847 (14.2%) subjects to whom it was proposed. The BREATHE study has collected a large amount of information on COPD variables from a representative sample of the general population of countries in the MENA region, which can be compared with other regional COPD initiatives.

  8. Adherence barriers and facilitators for cervical screening amongst currently disadvantaged women in the greater Cape Town region of South Africa

    PubMed Central

    De Abreu, Chantelle; Horsfall, Hannah

    2013-01-01

    Abstract Background In South Africa cervical cancer is the second most commonly occurring cancer amongst women, and black African women have the highest risk of developing this disease. Unfortunately, the majority of South African women do not adhere to recommended regular cervical screening. Objectives The purpose of this research was to explore the perceptions, experiences and knowledge regarding cervical screening of disadvantaged women in two informal settlements in South African urban areas. Method The Health Belief Model (HBM) provided a theoretical framework for this study. Four focus groups (n = 21) were conducted, using questions derived from the HBM, and thematic analysis was used to analyse the data. The ages of the women who participated ranged from 21 to 53 years. Results The analysis revealed lack of knowledge about screening as a key structural barrier to treatment. Other structural barriers were: time, age at which free screening is available, and health education. The psychosocial barriers that were identified included: fear of the screening procedure and of the stigmatisation in attending screening. The presence of physical symptoms, the perception that screening provides symptom relief, HIV status, and the desire to know one's physical health status were identified as facilitators of cervical screening adherence. Conclusion This knowledge has the potential to inform healthcare policy and services in South Africa. As globalisation persists and individuals continue to immigrate or seek refugee status in foreign countries, increased understanding and knowledge is required for successful acculturation and integration. Developed countries may therefore also benefit from research findings in developing countries.

  9. Combining Hydrology and Mosquito Population Models to Identify the Drivers of Rift Valley Fever Emergence in Semi-Arid Regions of West Africa

    PubMed Central

    Soti, Valérie; Tran, Annelise; Degenne, Pascal; Chevalier, Véronique; Lo Seen, Danny; Thiongane, Yaya; Diallo, Mawlouth; Guégan, Jean-François; Fontenille, Didier

    2012-01-01

    Background Rift Valley fever (RVF) is a vector-borne viral zoonosis of increasing global importance. RVF virus (RVFV) is transmitted either through exposure to infected animals or through bites from different species of infected mosquitoes, mainly of Aedes and Culex genera. These mosquitoes are very sensitive to environmental conditions, which may determine their presence, biology, and abundance. In East Africa, RVF outbreaks are known to be closely associated with heavy rainfall events, unlike in the semi-arid regions of West Africa where the drivers of RVF emergence remain poorly understood. The assumed importance of temporary ponds and rainfall temporal distribution therefore needs to be investigated. Methodology/Principal Findings A hydrological model is combined with a mosquito population model to predict the abundance of the two main mosquito species (Aedes vexans and Culex poicilipes) involved in RVFV transmission in Senegal. The study area is an agropastoral zone located in the Ferlo Valley, characterized by a dense network of temporary water ponds which constitute mosquito breeding sites. The hydrological model uses daily rainfall as input to simulate variations of pond surface areas. The mosquito population model is mechanistic, considers both aquatic and adult stages and is driven by pond dynamics. Once validated using hydrological and entomological field data, the model was used to simulate the abundance dynamics of the two mosquito species over a 43-year period (1961–2003). We analysed the predicted dynamics of mosquito populations with regards to the years of main outbreaks. The results showed that the main RVF outbreaks occurred during years with simultaneous high abundances of both species. Conclusion/Significance Our study provides for the first time a mechanistic insight on RVFV transmission in West Africa. It highlights the complementary roles of Aedes vexans and Culex poicilipes mosquitoes in virus transmission, and recommends the

  10. Estimation of human heat loss in five Mediterranean regions.

    PubMed

    Bilgili, M; Simsek, E; Sahin, B; Yasar, A; Ozbek, A

    2015-10-01

    This study investigates the effects of seasonal weather differences on the human body's heat losses in the Mediterranean region of Turkey. The provinces of Adana, Antakya, Osmaniye, Mersin and Antalya were chosen for the research, and monthly atmospheric temperatures, relative humidity, wind speed and atmospheric pressure data from 2007 were used. In all these provinces, radiative, convective and evaporative heat losses from the human body based on skin surface and respiration were analyzed from meteorological data by using the heat balance equation. According to the results, the rate of radiative, convective and evaporative heat losses from the human body varies considerably from season to season. In all the provinces, 90% of heat loss was caused by heat transfer from the skin, with the remaining 10% taking place through respiration. Furthermore, radiative and convective heat loss through the skin reached the highest values in the winter months at approximately between 110 and 140W/m(2), with the lowest values coming in the summer months at roughly 30-50W/m(2).

  11. Regional differences in temperature sensation and thermal comfort in humans.

    PubMed

    Nakamura, Mayumi; Yoda, Tamae; Crawshaw, Larry I; Yasuhara, Saki; Saito, Yasuyo; Kasuga, Momoko; Nagashima, Kei; Kanosue, Kazuyuki

    2008-12-01

    Sensations evoked by thermal stimulation (temperature-related sensations) can be divided into two categories, "temperature sensation" and "thermal comfort." Although several studies have investigated regional differences in temperature sensation, less is known about the sensitivity differences in thermal comfort for the various body regions. In the present study, we examined regional differences in temperature-related sensations with special attention to thermal comfort. Healthy male subjects sitting in an environment of mild heat or cold were locally cooled or warmed with water-perfused stimulators. Areas stimulated were the face, chest, abdomen, and thigh. Temperature sensation and thermal comfort of the stimulated areas were reported by the subjects, as was whole body thermal comfort. During mild heat exposure, facial cooling was most comfortable and facial warming was most uncomfortable. On the other hand, during mild cold exposure, neither warming nor cooling of the face had a major effect. The chest and abdomen had characteristics opposite to those of the face. Local warming of the chest and abdomen did produce a strong comfort sensation during whole body cold exposure. The thermal comfort seen in this study suggests that if given the chance, humans would preferentially cool the head in the heat, and they would maintain the warmth of the trunk areas in the cold. The qualitative differences seen in thermal comfort for the various areas cannot be explained solely by the density or properties of the peripheral thermal receptors and thus must reflect processing mechanisms in the central nervous system.

  12. Prioritizing agricultural pesticides used in South Africa based on their environmental mobility and potential human health effects.

    PubMed

    Dabrowski, James Michael; Shadung, Justinus Madimetja; Wepener, Victor

    2014-01-01

    South Africa is the largest user of pesticides in sub-Saharan Africa and many studies have highlighted the occurrence of pesticides in water resources. Poor management of water treatment facilities in combination with a relatively high dependency on untreated water from boreholes and rivers creates the potential for exposure of human communities to pesticides and their associated health effects. Pesticide use, physicochemical and toxicity data was therefore used to prioritize pesticides in terms of their potential risk to human health. After eliminating pesticides used in very low quantities, four indices were used to prioritize active ingredients applied in excess of 1000 kg per annum; the quantity index (QI) which ranked pesticides in terms of the quantity of their use; the toxicity potential index (TP) which ranked pesticides according to scores derived for their potential to cause five health effects (endocrine disruption, carcinogenicity, teratogenicity, mutagenicity and neurotoxicity); hazard potential index (HP) which multiplied the TP by an exposure potential score determined by the GUS index for each pesticide (to provide an indication of environmental hazard); and weighted hazard potential (WHP), which multiplied the HP for a pesticide by the ratio of its use to the total use of all pesticides in the country. The top 25 pesticides occurring in each of these indices were identified as priority pesticides, resulting in a combined total of 69 priority pesticides. A principal component analysis identified the indices that were most important in determining why a specific pesticide was included in the final priority list. As crop specific application pesticide use data was available it was possible to identify crops to which priority pesticides were applied to. Furthermore it was possible to prioritize crops in terms of the specific pesticide applied to the crop (by expressing the WHP as a ratio of the total amount of pesticide applied to the crop to the total

  13. Balancing Human Rights and Civil Liberties in an Emerging Democracy: Education Law, Policy and Practice in South Africa.

    ERIC Educational Resources Information Center

    Beckmann, Johan; Maile, Simeon; van Vollenhoven, Willie; Joubert Rika

    This outline is part of a collection of 54 papers from the 48th annual conference of the Education Law Association held in November 2002. It covers a presentation on changes in the law and social structure of South Africa. As an outline, it briefly touches upon a number of topics, but focuses mainly on South Africa's emerging "final"…

  14. The Episode of Genetic Drift Defining the Migration of Humans out of Africa Is Derived from a Large East African Population Size

    PubMed Central

    Elnour, Mohamed Ali; Isabirye, Dan; Okello, John; Hussien, Ayman; Kwiatksowski, Dominic; Hirbo, Jibril; Tishkoff, Sara; Ibrahim, Muntaser E.

    2014-01-01

    Human genetic variation particularly in Africa is still poorly understood. This is despite a consensus on the large African effective population size compared to populations from other continents. Based on sequencing of the mitochondrial Cytochrome C Oxidase subunit II (MT-CO2), and genome wide microsatellite data we observe evidence suggesting the effective size (Ne) of humans to be larger than the current estimates, with a foci of increased genetic diversity in east Africa, and a population size of east Africans being at least 2-6 fold larger than other populations. Both phylogenetic and network analysis indicate that east Africans possess more ancestral lineages in comparison to various continental populations placing them at the root of the human evolutionary tree. Our results also affirm east Africa as the likely spot from which migration towards Asia has taken place. The study reflects the spectacular level of sequence variation within east Africans in comparison to the global sample, and appeals for further studies that may contribute towards filling the existing gaps in the database. The implication of these data to current genomic research, as well as the need to carry out defined studies of human genetic variation that includes more African populations; particularly east Africans is paramount. PMID:24845801

  15. The episode of genetic drift defining the migration of humans out of Africa is derived from a large east African population size.

    PubMed

    Elhassan, Nuha; Gebremeskel, Eyoab Iyasu; Elnour, Mohamed Ali; Isabirye, Dan; Okello, John; Hussien, Ayman; Kwiatksowski, Dominic; Hirbo, Jibril; Tishkoff, Sara; Ibrahim, Muntaser E

    2014-01-01

    Human genetic variation particularly in Africa is still poorly understood. This is despite a consensus on the large African effective population size compared to populations from other continents. Based on sequencing of the mitochondrial Cytochrome C Oxidase subunit II (MT-CO2), and genome wide microsatellite data we observe evidence suggesting the effective size (Ne) of humans to be larger than the current estimates, with a foci of increased genetic diversity in east Africa, and a population size of east Africans being at least 2-6 fold larger than other populations. Both phylogenetic and network analysis indicate that east Africans possess more ancestral lineages in comparison to various continental populations placing them at the root of the human evolutionary tree. Our results also affirm east Africa as the likely spot from which migration towards Asia has taken place. The study reflects the spectacular level of sequence variation within east Africans in comparison to the global sample, and appeals for further studies that may contribute towards filling the existing gaps in the database. The implication of these data to current genomic research, as well as the need to carry out defined studies of human genetic variation that includes more African populations; particularly east Africans is paramount.

  16. Drying out the Nile? Regional Climate Change and Water Resources in East Africa with a focus on Lake Victoria and Lake Tana

    NASA Astrophysics Data System (ADS)

    Mottram, Ruth; Fox Maule, Cathrine; Thejll, Peter; Stendel, Martin; Drews, Martin; Davies, Sarah; Lamb, Henry

    2014-05-01

    The East African lakes Victoria and Tana are important local water resources for agriculture, fisheries and hydropower; they are also the main sources of the Nile. In this study we focus on the evaporative and evapotranspirative regimes of the hydrological basins for Lakes Tana and Victoria to determine how regional climate change under the A1B scenario is likely to affect the local and regional hydrology. We show results from a very high resolution (10km) simulation, where the state-of-the-art regional climate model (RCM) HIRHAM5 was driven by the global circulation model (GCM) ECHAM5 under the A1B scenario. Three time-slices have been investigated for present day (1980-1999), mid-century (2046-2065) and end of the 21st century (2080-2099) periods. Our analysis includes a comparison with a coarser 0.44o (~50 km) resolution run which demonstrates the importance of using high resolution (10km or higher) in RCM studies of this type to correctly simulate the seasonal and geographical characteristics of the present day east African monsoon system. The projections also indicate that climate change under the intermediate SRES A1B scenario is expected to cause more frequent failures of the East African rains with important consequences for the region and for the hydrology of the East African Lakes. This work introduces the proposed DACEA (Drivers of Aridity Change in East Africa) project which aims to investigate regional and global teleconnections that affect aridity in East Africa. Future work will combine climate palaeoproxies from Lake Tana and Lake Victoria with model experiments carried out with the EC-Earth coupled Ocean-Atmosphere General Circulation Model and downscaled to very high resolution with the RCM HIRHAM5 to determine regional and global scale influences on the African monsoon system. The HIRHAM5 simulations will be dynamically coupled to a regional hydrological model based on MIKE SHE, to evaluate the consequences and the feedback from the regional

  17. Filling the gap: a learning network for health an human rights in the Western Cape, South Africa.

    PubMed

    London, Leslie; Fick, Nicole; Tram, Khai Hoan; Stuttaford, Maria

    2012-06-15

    We draw on the experience of a Learning Network for Health and Human Rights (LN) involving collaboration between academic institutions and civil society organizations in the Western Cape, South Africa, aimed at identifying and disseminating best practice related to the right to health. The LN's work in materials development, participatory research, training and capacity-building for action, and advocacy for intervention illustrates important lessons for human rights practice. These include (i) the importance of active translation of knowledge and awareness into action for rights to be made real; (ii) the potential tension arising from civil society action, which might relieve the state of its obligations by delivering services that should be the state's responsibility-and hence the importance of emphasizing civil society's role in holding services accountable in terms of the right to health; (iii) the role of civil society organizations in filling a gap related to obligations to promote rights; (iv) the critical importance of networking and solidarity for building civil society capacity to act for health rights. Evidence from evaluation of the LN is presented to support the argument that civil society can play a key role in bridging a gap between formal state commitment to creating a human rights culture and realizing services and policies that enable the most vulnerable members of society to advance their health. Through access to information and the creation of spaces, both for participation and as a safe environment in which learning can be turned into practice, the agency of those most affected by rights violations can be redressed. We argue that civil society agency is critical to such action.

  18. Astronomy Landscape in Africa

    NASA Astrophysics Data System (ADS)

    Nemaungani, Takalani

    2015-01-01

    The vision for astronomy in Africa is embedded in the African Space Policy of the African Union in early 2014. The vision is about positioning Africa as an emerging hub for astronomy sciences and facilities. Africa recognized the need to take advantage of its natural resource, the geographical advantage of the clear southern skies and pristine sites for astronomy. The Pan African University (PAU) initiative also presents an opportunity as a post-graduate training and research network of university nodes in five regions of Africa and supported by the African Union. The Southern African node based in South Africa concentrates on space sciences which also includes astronomy. The PAU aims to provide the opportunity for advanced graduate training and postgraduate research to high-performing African students. Objectives also include promoting mobility of students and teachers and harmonizing programs and degrees.A number of astronomy initiatives have burgeoned in the Southern African region and these include the Southern Africa Largest Optical Telescope (SALT), HESS (High Energy Stereoscopic System), the SKA (Square Kilometre Array) and the AVN (African Very Long Baseline Interferometer Network). There is a growing appetite for astronomy sciences in Africa. In East Africa, the astronomy community is well organized and is growing - the East African Astronomical society (EAAS) held its successful fourth annual conference since 2010 on 30 June to 04 July 2014 at the University of Rwanda. Centred around the 'Role of Astronomy in Socio-Economic Transformation,' this conference aimed at strengthening capacity building in Astronomy, Astrophysics and Space Science in general, while providing a forum for astronomers from the region to train young and upcoming scientists.

  19. Functional annotation of HOT regions in the human genome: implications for human disease and cancer.

    PubMed

    Li, Hao; Chen, Hebing; Liu, Feng; Ren, Chao; Wang, Shengqi; Bo, Xiaochen; Shu, Wenjie

    2015-06-26

    Advances in genome-wide association studies (GWAS) and large-scale sequencing studies have resulted in an impressive and growing list of disease- and trait-associated genetic variants. Most studies have emphasised the discovery of genetic variation in coding sequences, however, the noncoding regulatory effects responsible for human disease and cancer biology have been substantially understudied. To better characterise the cis-regulatory effects of noncoding variation, we performed a comprehensive analysis of the genetic variants in HOT (high-occupancy target) regions, which are considered to be one of the most intriguing findings of recent large-scale sequencing studies. We observed that GWAS variants that map to HOT regions undergo a substantial net decrease and illustrate development-specific localisation during haematopoiesis. Additionally, genetic risk variants are disproportionally enriched in HOT regions compared with LOT (low-occupancy target) regions in both disease-relevant and cancer cells. Importantly, this enrichment is biased toward disease- or cancer-specific cell types. Furthermore, we observed that cancer cells generally acquire cancer-specific HOT regions at oncogenes through diverse mechanisms of cancer pathogenesis. Collectively, our findings demonstrate the key roles of HOT regions in human disease and cancer and represent a critical step toward further understanding disease biology, diagnosis, and therapy.

  20. How Changing Human Lifestyles are Shaping Europe's Regional Seas

    NASA Astrophysics Data System (ADS)

    Mee, L. D.; Lowe, C. D.; Langmead, O.; McQuatters-Gollop, A.; Attrill, M.; Cooper, P.; Gilbert, A.; Knudsen, S.; Garnacho, E.

    2007-05-01

    European society is experiencing unprecedented changes triggered by expansion of the European Union, the fall of Communism, economic growth and the onset of globalisation. Europe's regional seas, the Baltic, Black Sea, Mediterranean and North-East Atlantic (including the North Sea), provide key goods and services to the human population but have suffered from severe degradation in past decades. Their integrity as coupled social and ecological systems depends on how humanity will anticipate potential problems and deal with its ecological footprint in the future. We report the outcome of an EU-funded 15-country, 28 institution project entitled European Lifestyles and Marine Ecosystems (ELME). Our studies were designed to inform new EU policy and legislation that incorporates Ecosystem-Based Management. ELME has modelled the key relationships between economic and social drivers (D), environmental pressures (P) and changes in the state of the environment (S) in Europe's regional seas. We examined four key issues in each sea: habitat change, eutrophication, chemical pollution and fisheries. We developed conceptual models for each regional sea and employed a novel stochastic modelling technique to examine the interrelationship between key components of the conceptual models. We used the models to examine 2-3 decade projections of current trends in D, P and S and how a number of alternative development scenarios might modify these trends. These simulations demonstrate the vulnerability of Europe's seas to human pressure. As affluence increases in countries acceding to the EU, so does the demand for marine goods and services. There are `winners' and `losers' amongst marine species; the winners are often species that are opportunistic invaders or those with low economic value. In the case of eutrophication, semi-enclosed seas such as the Baltic or Black Sea are already affected by the `legacy of the past'; nutrients that have accumulated in soils, ground waters and

  1. Observations and regional modeling of aerosol optical properties, speciation and size distribution over Northern Africa and western Europe

    NASA Astrophysics Data System (ADS)

    Menut, Laurent; Siour, Guillaume; Mailler, Sylvain; Couvidat, Florian; Bessagnet, Bertrand

    2016-10-01

    The aerosol speciation and size distribution is modeled during the summer 2013 and over a large area encompassing Africa, Mediterranean and western Europe. The modeled aerosol is compared to available measurements such as the AERONET aerosol optical depth (AOD) and aerosol size distribution (ASD) and the EMEP network for surface concentrations of particulate matter PM2.5, PM10 and inorganic species (nitrate, sulfate and ammonium). The main goal of this study is to quantify the model ability to realistically model the speciation and size distribution of the aerosol. Results first showed that the long-range transport pathways are well reproduced and mainly constituted by mineral dust: spatial correlation is ≈ 0.9 for AOD and Ån