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Sample records for african west coast

  1. Evolution of a Paleoproterozoic “weak type” orogeny in the West African Craton (Ivory Coast)

    NASA Astrophysics Data System (ADS)

    Vidal, M.; Gumiaux, C.; Cagnard, F.; Pouclet, A.; Ouattara, G.; Pichon, M.

    2009-11-01

    The Paleoproterozoic domain of the Ivory Coast lies in the central part of the West African Craton (WAC) and is mainly constituted by TTG, greenstones, supracrustal rocks and leucogranites. A compilation of metamorphic and radiometric data highlights that: i) metamorphic conditions are rather homogeneous through the domain, without important metamorphic jumps, ii) HP-LT assemblages are absent and iii) important volumes of magmas emplaced during the overall Paleoproterozoic orogeny suggesting the occurrence of long-lived rather hot geotherms. Results of the structural analysis, focused on three areas within the Ivory Coast, suggest that the deformation is homogeneous and distributed through the Paleoproterozoic domain. In details, results of this study point out the long-lived character of vertical movements during the Eburnean orogeny with a two folds evolution. The first stage is characterized by the development of "domes and basins" geometries without any boundary tectonic forces and the second stage is marked by coeval diapiric movements and horizontal regional-scale shortening. These features suggest that the crust is affected by vertical movements during the overall orogeny. The Eburnean orogen can then be considered as an example of long-lived Paleoproterozoic "weak type" orogen.

  2. West African crude production diversifies

    SciTech Connect

    Aalund, L.

    1983-06-01

    Nigeria, with its seven crude-oil export streams, dominated West African production and accounted for over 70% of the depressed 1.8 million b/d output from the region last year. However, during the 1970s a flurry of new producing fields, primarily off the African coast, diversified production among a number of countries and touched off a wave of oil activity. The Journal takes a close look at the quality of West African oil in this installment of assays on world export crudes. This issue covers, in alphabetical order, Bonny Light (Nigeria) to Espoir (Ivory Coast). A following issue will wrap up West Africa by presenting assays on crudes from Forcados Blend (Nigeria) to Zaire Crude (Zaire).

  3. Improvisation in West African Musics.

    ERIC Educational Resources Information Center

    Locke, David

    1980-01-01

    Discussed is music of the sub-Sahara. Vocal, instrumental, and dance drumming from the Sudan Desert, the North Coast, East Horn, Central and West Africa, and contrapuntal yodeling of Pygmies is described. For African musicians, the ability to improvise, and creativity, are gifts from God. Includes selected readings and recordings. (KC)

  4. The Guiana and the West African Shield Palaeoproterozoic grouping: new palaeomagnetic data for French Guiana and the Ivory Coast

    NASA Astrophysics Data System (ADS)

    Nomade, Sébastien; Chen, Yan; Pouclet, André; Féraud, Gilbert; Théveniaut, Hervé; Daouda, Bertin Yao; Vidal, Max; Rigolet, Cécile

    2003-09-01

    The aim of this study is to document the Palaeoproterozoic palaeomagnetic database for the Guiana and West African Shields in order to better understand the paleogeographic evolution of these two cratons. A total of 59 sites were sampled (33 in French Guiana and 26 in the Ivory Coast) in granites and metavolcanic rocks. Magnetic, petrographic and palaeomagnetic investigations were carried out on these rocks. Magnetic experiments and petrographic observations show that undeformed magnetite is the main magnetic remanent carrier in granites of French Guiana and both magnetite and haematite in rocks from the Ivory Coast. Both thermal and magnetic alternating-field demagnetizations were applied to the rocks. Four high-temperature magnetic remanent directions were isolated in French Guiana and the Ivory Coast. These directions are distinct from the present Earth's field and to the local Early Jurassic palaeomagnetic components. Reversal and contact tests were obtained for the collection from French Guiana. Based on these arguments and mineralogical investigations, we propose that the magnetic remanence represent a Palaeoproterozoic magnetization. Four virtual palaeomagnetic poles were calculated: GUI1, GUI2 for French Guiana; IC1 and IC2 for the Ivory Coast with their corresponding coordinates: GUI1: λGUI1=-62°N, φGUI1= 61°E, k= 18, A95= 10°, N= 15; GUI2: λGUI2=-5°N, φGUI2= 50°E, k= 26, A95= 18°, N= 5; IC1: λIC1=-82°N, φIC1= 292°N, k= 28, A95= 13°, N= 6; IC2: λIC2=-25°N, φIC2= 83°E, k= 11, A95= 16°, N= 9. The magnetization age ranged from 2.04 to 1.97 Ga for the French Guiana poles (40Ar/39Ar) and between 2.10 to 2.00 Ga for the Ivory Coast poles (startigraphic ages). Combining these new palaeomagnetic poles and previously published data, two apparent polar wander paths were proposed for these two shields. The comparison of these two Palaeoproterozoic paths seems to indicate that the two cratons belonged to the same block at about 2.00 Ga but

  5. On some sea cucumbers (Echinodermata: Holothuroidea) from off the south and west coasts of South Africa collected by the South African Environmental and Observation Network (SAEON).

    PubMed

    Thandar, Ahmed S; Rambaran, Ryan

    2015-08-07

    Twenty four specimens of holothuroids recently received from the South African Environmental and Observation Network (SAEON), collected from off the south and west coasts of South Africa, are herein recorded and/or described. The specimens comprise eight nominal and one indeterminate species and represent both shallow-water and deep-sea forms, distributed from Plettenberg Bay to just north of Lambert's Bay in the Western Cape Province. There are no new species but two new records for the South African region and extensions of horizontal and bathymetric distributions of the other species. Additions to the South African fauna are Zygothuria lactea (Théel, 1886) and Synallactes cf. challengeri (Théel, 1886). The paper also contains the first definite record of Thyone venusta Selenka, 1868, originally described from the Red Sea. Distribution ranges of the following species have been altered Synallactes viridilimus Cherbonnier, 1952; S. mollis Cherbonnier, 1952 and Psuedostichopus langeae Thandar, 2009.

  6. A West African Link

    ERIC Educational Resources Information Center

    Cook, Angela; Davies, Penny

    2003-01-01

    The authors visited Ghana in West Africa to strengthen a link established the previous year as part of Channel 4's "On the Line" project. The initial link established in 1999/2000 was between an all-age special school in Enfield and a similar school in Accra. Over the course of that year further partnerships were created between five UK schools…

  7. Eighteenth annual West Coast theoretical chemistry conference

    SciTech Connect

    1997-05-01

    Abstracts are presented from the eighteenth annual west coast theoretical chemistry conference. Topics include molecular simulations; quasiclassical simulations of reactions; photodissociation reactions; molecular dynamics;interface studies; electronic structure; and semiclassical methods of reactive systems.

  8. An Introduction to West African Literature.

    ERIC Educational Resources Information Center

    Taiwo, Oladele

    Intended to provide help for those interested in studying West African literature, this book is divided into three parts. Part One provides background information: the various African oral traditions are discussed, related to the way of life of the people, and examined for the extent to which they form the basis of present West African literary…

  9. Black English Near its Roots: The Transplanted West African Creoles.

    ERIC Educational Resources Information Center

    Birmingham, John C., Jr.

    It seems highly likely that many of the features of Black American English can be traced back to the Afro-Portuguese Creole dialects that sprang up in the fifteenth century in Portuguese slave camps along the West African coast, particularly in the Gulf of Guinea area, the area of greatest concentration of activity during the slave trade. This…

  10. Plans for West Coast STS launch capability

    NASA Technical Reports Server (NTRS)

    Murphy, W. P.; Marshall, J. H.

    1979-01-01

    The layout and scope of operations of the Vandenberg AFB West Coast Launch Site for the Space Shuttle are examined. The launch site intended for the first West Coast launch in December 1983 is being constructed by the United States Air Force. Topic discussed include site/selection/management/concepts, Shuttle hardware flow and related facilities, launch pad operations, orbiter erection at SLC-6 VAFB, solid rocket booster operations, and payload ground processing. In conclusion it is noted that NASA and DOD personnel are working together to ensure that the launch site is completed on schedule at minimum cost.

  11. WEST COAST REGIONAL CARBON SEQUESTRATION PARTNERSHIP

    SciTech Connect

    Larry Myer; Terry Surles; Kelly Birkinshaw

    2004-01-01

    The West Coast Regional Carbon Sequestration Partnership is one of seven partnerships which have been established by the US Department of Energy (DOE) to evaluate carbon dioxide capture, transport and sequestration (CT&S) technologies best suited for different regions of the country. The West Coast Region comprises Arizona, California, Nevada, Oregon, Washington, and the North Slope of Alaska. Led by the California Energy Commission, the West Coast Partnership is a consortium of over thirty five organizations, including state natural resource and environmental protection agencies; national labs and universities; private companies working on CO{sub 2} capture, transportation, and storage technologies; utilities; oil and gas companies; nonprofit organizations; and policy/governance coordinating organizations. In an eighteen month Phase I project, the Partnership will evaluate both terrestrial and geologic sequestration options. Work will focus on five major objectives: (1) Collect data to characterize major CO{sub 2} point sources, the transportation options, and the terrestrial and geologic sinks in the region, and compile and organize this data via a geographic information system (GIS) database; (2) Address key issues affecting deployment of CT&S technologies, including storage site permitting and monitoring, injection regulations, and health and environmental risks (3) Conduct public outreach and maintain an open dialogue with stakeholders in CT&S technologies through public meetings, joint research, and education work (4) Integrate and analyze data and information from the above tasks in order to develop supply curves and cost effective, environmentally acceptable sequestration options, both near- and long-term (5) Identify appropriate terrestrial and geologic demonstration projects consistent with the options defined above, and create action plans for their safe and effective implementation A kickoff meeting for the West Coast Partnership was held on Sept 30-Oct

  12. Y Chromosome Lineages in Men of West African Descent

    PubMed Central

    Keita, Shomarka O. Y.; Kittles, Rick A.

    2012-01-01

    The early African experience in the Americas is marked by the transatlantic slave trade from ∼1619 to 1850 and the rise of the plantation system. The origins of enslaved Africans were largely dependent on European preferences as well as the availability of potential laborers within Africa. Rice production was a key industry of many colonial South Carolina low country plantations. Accordingly, rice plantations owners within South Carolina often requested enslaved Africans from the so-called “Grain Coast” of western Africa (Senegal to Sierra Leone). Studies on the African origins of the enslaved within other regions of the Americas have been limited. To address the issue of origins of people of African descent within the Americas and understand more about the genetic heterogeneity present within Africa and the African Diaspora, we typed Y chromosome specific markers in 1,319 men consisting of 508 west and central Africans (from 12 populations), 188 Caribbeans (from 2 islands), 532 African Americans (AAs from Washington, DC and Columbia, SC), and 91 European Americans. Principal component and admixture analyses provide support for significant Grain Coast ancestry among African American men in South Carolina. AA men from DC and the Caribbean showed a closer affinity to populations from the Bight of Biafra. Furthermore, 30–40% of the paternal lineages in African descent populations in the Americas are of European ancestry. Diverse west African ancestries and sex-biased gene flow from EAs has contributed greatly to the genetic heterogeneity of African populations throughout the Americas and has significant implications for gene mapping efforts in these populations. PMID:22295064

  13. Children Ask Questions about West African Art.

    ERIC Educational Resources Information Center

    Abercrombie, Denice; Cochran, Mathilda; Mims, Margaret

    1997-01-01

    Presents a collection of questions that fifth-grade students asked about African artwork and answers provided by staff from the Museum of Fine Arts in Houston, Texas. Observes that students' interest in important visual aspects of the art creates lead-ins to more detailed discussions of West African art and culture. (DSK)

  14. West African Folktales [and] Instructor's Manual.

    ERIC Educational Resources Information Center

    Gale, Steven H.

    Traditionally, an important function of folktales in West Africa has been to educate, as the older generation imparts knowledge to younger members of the family, tribe, societal unit, or ethnic group both informally in everyday life and more formally within the context of the bush schools. This anthology of West African folk literature offers more…

  15. 75 FR 75638 - Fisheries Off West Coast States; Modifications of the West Coast Commercial and Recreational...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-06

    .... SUPPLEMENTARY INFORMATION: In the 2010 annual management measures for ocean salmon fisheries (75 FR 24482, May 5..., inseason action 11 (75 FR 54791, September, 9, 2010) imposed an open period landing and possession limit of... fisheries (75 FR 24482, May 5, 2010), the West Coast Salmon Plan, and regulations implementing the...

  16. 78 FR 30780 - Fisheries Off West Coast States; Modifications of the West Coast Commercial Salmon Fisheries...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-23

    ... measures for ocean salmon fisheries (78 FR 25865, May 3, 2013), NMFS announced the commercial and... announced for the 2013 Ocean Salmon Fisheries and 2014 fisheries opening prior to May 1, 2014 (78 FR 25865... ocean salmon fisheries (78 FR 25865, May 3, 2013), the West Coast Salmon Fishery Management Plan...

  17. 78 FR 24360 - Fisheries Off West Coast States; Modifications of the West Coast Commercial and Recreational...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-25

    .... SUPPLEMENTARY INFORMATION: Background In the 2012 annual management measures for ocean salmon fisheries (77 FR... the 2012 Ocean Salmon Fisheries and 2012 fisheries opening prior to May 1, 2013 (77 FR 25915, May 2... management measures for ocean salmon fisheries (77 FR 25915, May 2, 2012), the West Coast Salmon Plan,...

  18. 78 FR 35153 - Fisheries Off West Coast States; Modifications of the West Coast Commercial Salmon Fisheries...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-12

    ... ocean salmon fisheries (78 FR 25865, May 3, 2013), NMFS announced the commercial and recreational... the annual management measures for ocean salmon fisheries (78 FR 25865, May 3, 2013), the West Coast...,700 Chinook guideline is not exceeded (78 FR 25865, May 3, 2013). NMFS is authorized to...

  19. 78 FR 70509 - Fisheries Off West Coast States; Modifications of the West Coast Commercial and Recreational...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-26

    ... the 2013 annual management measures for ocean salmon fisheries (78 FR 25865, May 3, 2013), NMFS... fisheries (78 FR 25865, May 3, 2013), the West Coast Salmon Fishery Management Plan (Salmon FMP), and... the OR-KMZ and supersedes inseason action 10 (76 FR 50347). This action was taken to allow access...

  20. 78 FR 50347 - Fisheries Off West Coast States; Modifications of the West Coast Commercial Salmon Fisheries...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-19

    ... salmon fisheries (78 FR 25865, May 3, 2013), NMFS announced the commercial and recreational fisheries in... the 2013 ocean salmon fisheries and 2014 fisheries opening prior to May 1, 2014 (78 FR 25865, May 3... management measures for ocean salmon fisheries (78 FR 25865, May 3, 2013), the West Coast Salmon...

  1. Intimate Partner Violence among West African Immigrants

    PubMed Central

    AKINSULURE-SMITH, ADEYINKA M.; CHU, TRACY; KEATLEY, EVA; RASMUSSEN, ANDREW

    2013-01-01

    Although the number of African immigrants arriving to the United States has increased significantly, there has been little investigation regarding their experiences of intimate partner violence or coping strategies. This study used focus groups and individual interviews to explore intimate partner violence among 32 heterosexual West African immigrants. Results suggest that although cultural expectations influence their coping strategies, West African–born men and women face different realities, with women reporting multiple instances of abuse and a sense of frustration with the existing options for assistance. Although participants discussed multilevel support structures within the immediate West African community to address intimate partner violence, all of these options maintained a gender hierarchy, leaving women dissatisfied. Challenges and barriers to partner violence resolution and coping strategies are identified. Results are examined in terms of their implications for addressing the needs of this underserved population. Implications for future research and services are discussed and highlighted. PMID:23730146

  2. Marine West Coast Forests, Chapter 9

    USGS Publications Warehouse

    Perakis, Steven S.; Geiser, Linda H.; Lilleskov, Erik A.; Pardo, Linda H.; Robin-Abbott, Molly J.; Driscoll, Charles T.

    2011-01-01

    Human activities have greatly increased nitrogen emissions and deposition across large areas of Earth. Although nitrogen is an essential nutrient for plant growth, too much nitrogen in excess of critical loads leads to losses of biodiversity, soil and stream acidification, nutrient imbalances, and other deleterious effects. In a new report quantifying critical loads of nitrogen deposition across the United States, USGS scientist Steve Perakis and co-authors provided a chapter about responses of marine west coast forests. Much of this region is understudied with respect to nitrogen deposition, and in this chapter the authors identify known adverse effects and estimate critical loads of nitrogen deposition for western Oregon and Washington and southeast Alaska forests. Perakis also contributed to the synthesis chapter, which includes background, objectives, advantages and uncertainties of critical loads, an overview of critical loads across U.S. ecoregions, and other topics.

  3. Roots and Branches: Contemporary Essays by West Coast Writers.

    ERIC Educational Resources Information Center

    Junker, Howard, Ed.

    Celebrating the vitality and diversity of West Coast writing, this book is a collection of 35 essays by writers based in California, Oregon, Washington, and Alaska. Loosely organized around the ideas that West Coast writers often look to their roots elsewhere and that they pursue new directions as varied as their roots, the collection presents a…

  4. Phytoplankton off the West Coast of Africa

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Just off the coast of West Africa, persistent northeasterly trade winds often churn up deep ocean water. When the nutrients in these deep waters reach the ocean's surface, they often give rise to large blooms of phytoplankton. This image of the Mauritanian coast shows swirls of phytoplankton fed by the upwelling of nutrient-rich water. The scene was acquired by the Medium Resolution Imaging Spectrometer (MERIS) aboard the European Space Agency's ENVISAT. MERIS will monitor changes in phytoplankton across Earth's oceans and seas, both for the purpose of managing fisheries and conducting global change research. NASA scientists will use data from this European instrument in the Sensor Intercomparison and Merger for Biological and Interdisciplinary Oceanic Studies (SIMBIOS) program. The mission of SIMBIOS is to construct a consistent long-term dataset of ocean color (phytoplankton abundance) measurements made by multiple satellite instruments, including the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) and the Moderate-Resolution Imaging Spectroradiometer (MODIS). For more information about MERIS and ENVISAT, visit the ENVISAT home page. Image copyright European Space Agency

  5. 1. AERIAL VIEW TO WEST OF COAST GUARD AIR STATION ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. AERIAL VIEW TO WEST OF COAST GUARD AIR STATION SAN FRANCISCO, SHOWING ALL MAJOR BUILDINGS. 8X10 black and white silver gelatin print. United States Coast Guard, February 1962. - U.S. Coast Guard Air Station San Francisco, 1020 North Access Road, San Francisco, San Francisco County, CA

  6. Heat flow from the West African shield

    SciTech Connect

    Brigaud, F.; Lucazeau, F.; Ly, S.; Sauvage, J.F.

    1985-09-01

    The heat flow over Precambrian shields is generally lower than over other continental provinces. Previous observations at 9 sites of the West African shield have shown that heat flow ranges from 20 mW m/sup -2/ in Niger to 38-42 mW m/sup -2/ in Liberia, Ghana and Nigeria. Since some of these values are lower than expected for Precambrian shields, it is important to find out whether or not they are representative of the entire shield before trying to derive its thermal structure. In this paper, we present new heat flow determinations from seven sites of the West African shield. These indicate that the surface heat flow is comparable with that of other Precambrian shields in the world.

  7. Sequestration Options for the West Coast States

    SciTech Connect

    Myer, Larry

    2006-04-30

    The West Coast Regional Carbon Sequestration Partnership (WESTCARB) is one of seven partnerships that have been established by the U.S. Department of Energy (DOE) to evaluate carbon capture and sequestration (CCS) technologies best suited for different regions of the country. The West Coast Region comprises Arizona, California, Nevada, Oregon, Washington, Alaska, and British Columbia. Led by the California Energy Commission, WESTCARB is a consortium of about 70 organizations, including state natural resource and environmental protection agencies; national laboratories and universities; private companies working on carbon dioxide (CO{sub 2}) capture, transportation, and storage technologies; utilities; oil and gas companies; nonprofit organizations; and policy/governance coordinating organizations. Both terrestrial and geologic sequestration options were evaluated in the Region during the 18-month Phase I project. A centralized Geographic Information System (GIS) database of stationary source, geologic and terrestrial sink data was developed. The GIS layer of source locations was attributed with CO{sub 2} emissions and other data and a spreadsheet was developed to estimate capture costs for the sources in the region. Phase I characterization of regional geological sinks shows that geologic storage opportunities exist in the WESTCARB region in each of the major technology areas: saline formations, oil and gas reservoirs, and coal beds. California offers outstanding sequestration opportunities because of its large capacity and the potential of value-added benefits from enhanced oil recovery (EOR) and enhanced gas recovery. The estimate for storage capacity of saline formations in the ten largest basins in California ranges from about 150 to about 500 Gt of CO{sub 2}, the potential CO{sub 2}-EOR storage was estimated to be 3.4 Gt, and the cumulative production from gas reservoirs suggests a CO{sub 2} storage capacity of 1.7 Gt. A GIS-based method for source

  8. West Indian Ocean variability and East African fish catch.

    PubMed

    Jury, M; McClanahan, T; Maina, J

    2010-08-01

    We describe marine climate variability off the east coast of Africa in the context of fish catch statistics for Tanzania and Kenya. The time series exhibits quasi-decadal cycles over the period 1964-2007. Fish catch is up when sea surface temperature (SST) and atmospheric humidity are below normal in the tropical West Indian Ocean. This pattern relates to an ocean Rossby wave in one phase of its east-west oscillation. Coastal-scale analyses indicate that northward currents and uplift on the shelf edge enhance productivity of East African shelf waters. Some of the changes are regulated by the south equatorial current that swings northward from Madagascar. The weather is drier and a salty layer develops in high catch years. While the large-scale West Indian Ocean has some impact on East African fish catch, coastal dynamics play a more significant role. Climatic changes are reviewed using 200 years of past and projected data. The observed warming trend continues to increase such that predicted SST may reach 30 degrees C by 2100 while SW monsoon winds gradually increase, according to a coupled general circulation model simulation with a gradual doubling of CO(2). PMID:20471674

  9. 75 FR 13081 - Fisheries off West Coast States; Pacific Coast Groundfish Fishery; Trawl Rationalization Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-18

    ... National Oceanic and Atmospheric Administration RIN 0648-XRO1 Fisheries off West Coast States; Pacific Coast Groundfish Fishery; Trawl Rationalization Program AGENCY: National Marine Fisheries Service (NMFS... trawl rationalization program that would affect the limited entry trawl fishery of the Pacific...

  10. 76 FR 68658 - Fisheries Off West Coast States; Pacific Coast Groundfish Harvest Specifications and Management...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-07

    ... measures for most species (75 FR 27508, May 11, 2011), in part pursuant to NMFS' emergency authority under... National Oceanic and Atmospheric Administration 50 CFR Part 660 RIN 0648-BA01 Fisheries Off West Coast States; Pacific Coast Groundfish Harvest Specifications and Management Measures for the Remainder of...

  11. 75 FR 75449 - Magnuson-Stevens Act Provisions; Fisheries Off West Coast States; Pacific Coast Groundfish...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-03

    ...: The proposed rule that published on November 3, 2010 (75 FR 67810), establishes the 2011-2012 harvest... National Standard 1 Guidelines (74 FR 3178, January 16, 2009). The proposed rule published in the Federal... Provisions; Fisheries Off West Coast States; Pacific Coast Groundfish Fishery; Comment Period...

  12. Geographic signatures of North American West Coast estuaries

    USGS Publications Warehouse

    Emmett, Robert; Llansó, Roberto; Newton, Jan; Thom, Ron; Hornberger, Michelle; Morgan, Cheryl; Levings, Colin; Copping, Andrea; Fishman, Paul

    2000-01-01

    West Coast estuaries are geologically young and composed of a variety of geomorphological types. These estuaries range from large fjords to shallow lagoons; from large to low freshwater flows. Natural hazards include E1 Niños, strong Pacific storms, and active tectonic activity. West Coast estuaries support a wide range of living resources: five salmon species, harvestable shellfish, waterfowl and marine birds, marine mammals, and a variety of algae and plants. Although populations of many of these living resources have declined (salmonids), others have increased (marine mammals). West Coast estuaries are also centers of commerce and increasingly large shipping traffic. The West Coast human population is rising faster than most other areas of the U.S. and Canada, and is distributed heavily in southern California, the San Francisco Bay area, around Puget Sound, and the Fraser River estuary. While water pollution is a problem in many of the urbanized estuaries, most estuaries do not suffer from poor water quality. Primary estuarine problems include habitat alterations, degradation, and loss; diverted freshwater flows; marine sediment contamination; and exotic species introductions. The growing West Coast economy and population are in part related to the quality of life, which is dependent on the use and enjoyment of abundant coastal natural resources.

  13. Do West African thunderstorms predict the intensity of Atlantic hurricanes?

    NASA Astrophysics Data System (ADS)

    Price, Colin; Reicher, Naama; Yair, Yoav

    2015-04-01

    Since 85% of all major Atlantic hurricanes originate as thunderstorm clusters in equatorial Africa, we have investigated the connection between these African thunderstorms and the consequent development of these disturbances into tropical storms. We have analyzed Meteosat infrared cloud top temperature data to determine the areal coverage of cold cloud tops over a 6 year period from 2005 to 2010. In addition, hurricane statistics from the same period (intensity, date of generation, location, and maximum winds) were obtained from the National Hurricane Center database. We first show that the areal coverage of cold clouds (with brightness temperatures Tb < -50°C) in tropical Africa is a good indicator of the monthly number of African Easterly Waves (AEWs) leaving the west coast of tropical Africa. Furthermore, the AEWs that develop into tropical storms have a significantly larger area covered by cold cloud tops compared with nondeveloping waves. Finally, we show that on a storm-by-storm basis, the cold cloud coverage in West Africa is positively correlated (r = 0.57) with the accumulated cyclone energy of the future tropical cyclones that develop out of these waves.

  14. Do West African Thunderstorms Predict the Intensity of Atlantic Hurricanes?

    NASA Astrophysics Data System (ADS)

    Price, Colin; Reicher, Naama; Yair, Yoav

    2015-04-01

    Since 85% of all major Atlantic hurricanes originate as thunderstorm clusters in equatorial Africa, we have investigated the connection between these African thunderstorms and the consequent development of these disturbances into tropical storms. We have analyzed METEOSAT infrared cloud-top temperature data to determine the areal coverage of cold cloud tops over a six year period from 2005-2010. In addition, hurricane statistics from the same period (intensity, date of generation, location, maximum winds) were obtained from the National Hurricane Center (NHC) data base. We first show that the areal coverage of cold clouds (with brightness temperatures Tb<-50oC) in tropical Africa is a good indicator of the monthly number of African Easterly Waves (AEWs) leaving the west coast of tropical Africa. Furthermore, the AEWs that develop into tropical storms have a significantly larger area covered by cold cloud tops compared with non-developing waves. Finally, we show that on a storm-by-storm basis, the cold cloud coverage in West Africa is positively correlated (r=0.57) with the accumulated cyclone energy (ACE) of the future tropical cyclones that develop out of these waves.

  15. Complicating Culturally Relevant Pedagogy: Unpacking West African Immigrants' Cultural Identities

    ERIC Educational Resources Information Center

    Allen, Keisha McIntosh; Jackson, Iesha; Knight, Michelle G.

    2012-01-01

    This study presents findings from a case study of 18 second- and 1.5-generation West African immigrants. We draw upon notions of elusive culture and indigenous knowledges to highlight participants' complex cultural identities and respond to anti-immigration discourses through positioning West African immigrant students as assets in American…

  16. North-South Migration of West Coast Low Pressure Centers

    ERIC Educational Resources Information Center

    McIntosh, C. Barron

    1974-01-01

    Monthly maps of low pressure centers are presented here to attempt a concrete representation that may help students to understand the seasonal change from dry months to wet months along the mid-latitude west coast as a seasonal north-south migration of factors controlling rain and drought. (Author/JH)

  17. Sulfur Upwelling off the African Coast

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Though these aquamarine clouds in the waters off the coast of northern Namibia may look like algae blooms, they are in fact clouds of sulfur produced by anaerobic bacteria on the ocean's floor. This image of the sulfur-filled water was taken on April 24, 2002, by the Sea-viewing Wide Field-of-View Sensor (SeaWiFS), flying aboard the Orbview-2 satellite. The anaerobic bacteria (bacteria that can live without oxygen) feed upon algae carcasses that exist in abundance on the ocean's floor off of Namibia. As the bacteria ingest the algae husks, they produce hydrogen sulfide, which slowly builds up in the sea-floor sediments. Eventually, the hydrogen sulfide reaches the point where the sediment can no longer contain it, and it bubbles forth. When this poisonous chemical reaches the surface, it combines with the oxygen in the upper layers of the ocean to create clouds of pure sulfur. The sulfur causes the Namibian coast to smell like rotten eggs, and the hydrogen sulfide will often kill fish and drive lobsters away. For more information, read: A Bloom By Any Other Name A high-resolution (250 meters per pixel) image earlier on the 24th taken from the Moderate-Resolution Imaging Spectroradiometer (MODIS) shows additional detail in the plumes. Image courtesy the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE. MODIS image courtesy Jacques Descloitres, MODIS Land Rapid Response Team at NASA GSFC

  18. 77 FR 75101 - Fisheries Off West Coast States; West Coast Salmon Fisheries; Amendment 17 to the Salmon Fishery...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-19

    ... approved portions of Amendment 16 were made effective in a Final Rule (76 FR 81851, December 29, 2011). In... on November 5, 2012. NMFS published a Notice of Availability in the Federal Register (77 FR 67327... States; West Coast Salmon Fisheries; Amendment 17 to the Salmon Fishery Management Plan AGENCY:...

  19. Rainfall variability over the East African coast

    NASA Astrophysics Data System (ADS)

    Gamoyo, Majambo; Reason, Chris; Obura, David

    2015-04-01

    The coastal region of Kenya and Tanzania experiences two rainy seasons per year (October-November-December (OND) and March-April-May (MAM)) and has an economy that is highly dependent on and vulnerable to the amounts and timing of rainfall during these seasons. Most of the interannual variability in OND seasonal rainfall totals relate to El Niño Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD) events. While these relationships are fairly well documented and understood, there is a relatively poor understanding of the timing and intensity of the rainfall during ENSO/IOD seasons. In an attempt to improve understanding on this topic, daily rainfall station data, dekad and seasonal satellite rainfall estimates and Normalized Difference Vegetation Index (NDVI) imagery are analyzed for two recent OND seasons with El Niño conditions. These are OND 2006 which was characterized by devastating floods over the region and 2009 when the magnitude and spatial extent of the above average rainfall patterns were smaller. Daily rainfall data for the Tanzanian coastal stations showed that Tanga and Dar es Salaam (north and central coast) experienced few dry spells and several relatively intense wet spells during OND 2006 whereas at Mtwara, on the south coast, there were two very intense wet spells and a number of dry spells during the season. In OND 2009, only the north coast (Tanga) experienced above average rainfall, comprised of three wet spells with the one about a month after the beginning of the season being very intense. These data highlight the complexity of the rainfall distributions in the coastal region. A shift of the Walker circulation over coastal East Africa with strong uplift there seemed to be responsible for the very wet conditions during OND 2006. The marine air mass being advected from the western tropical Indian Ocean towards East Africa contained more moisture than average. Similar, but weaker, horizontal circulation anomalies occurred in OND 2009

  20. US west coast revisited: An aeromagnetic perspective

    SciTech Connect

    Zietz, I.; Johnson, P.R. ); Bond, K.R. )

    1990-04-01

    A new compilation of magnetic data for the western conterminous United States and offshore areas provides significant information about crustal units and structures in the region. Features shown on the compilation include a magnetic quiet zone along the coast and two lineaments inland. The magnetic quiet zone correlates with the accretionary prism at the western edge of the North American plate and overlies subducted ocean crust; abrupt termination of ocean-floor magnetic anomalies at, or a short distance east of, the toe of the accretionary prism is an inferred effect subduction-induced low-temperature metamorphism of the ocean crust. The Puget Lowlands-San Joaquin lineament is an alignment of high-intensity magnetic anomalies that in the south, and possibly also in the north, are cause by bodies of mafic-ultramafic rocks accreted to North America during the Mesozoic and Tertiary. The lineup of the highs and the inferred lineup of the causative bodies may reflect fundamental structures that control Mesozoic and Tertiary evolution of the continental margin. The Mojave Desert lineament, a distinctive chain of short-wavelength magnetic anomalies in southern California, coincides partly with a zone of Mesozoic intrusions and the Cenozoic San Andreas fault system, but is likely to be older than both in origin and may reflect a Mesozoic or older crustal discontinuity.

  1. Regional analysis of convective systems during the West African monsoon

    NASA Astrophysics Data System (ADS)

    Guy, Bradley Nicholas

    characteristics (e.g. total precipitation and vertical reflectivity profiles) at the inland and maritime sites. The wave regime also resulted in an increased population of the largest observed mesoscale convective systems observed near the coast, which led to an increase in stratiform precipitation. Despite this increase, differentiation of convective strength characteristics was less obvious between wave and no-wave regimes at the coast. Due to the propagating nature of these advecting mesoscale convective systems, interaction with the regional thermodynamic and dynamic environment appears to result in more variability than enhancements due to the wave regime, independent of location. A 13-year (1998-2010) climatology of mesoscale convective characteristics associated with the West African monsoon are also investigated using precipitation radar and passive microwave data from the NASA Tropical Rainfall Measuring Mission satellite. Seven regions defined as continental northeast and northwest, southeast and southwest, coastal, and maritime north and south are compared to analyze zonal and meridional differences. Data are categorized according to identified African easterly wave (AEW) phase and when no wave is present. While some enhancements are observed in association with AEW regimes, regional differences were generally more apparent than wave vs. no-wave differences. Convective intensity metrics confirm that land-based systems exhibit stronger characteristics, such as higher storm top and maximum 30-dBZ heights and significant 85-GHz brightness temperature depressions. Continental systems also contain a lower fraction of points identified as stratiform. Results suggest that precipitation processes also varied depending upon region and AEW regime, with warm-rain processes more apparent over the ocean and the southwest continental region and ice-based microphysics more dominant over land, including mixed-phase processes. AEW regimes did show variability in stratiform fraction and

  2. 7 CFR 319.8-12 - From the West Coast of Mexico.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 5 2010-01-01 2010-01-01 false From the West Coast of Mexico. 319.8-12 Section 319.8... Conditions for the Entry of Cotton and Covers from Mexico § 319.8-12 From the West Coast of Mexico. Contingent upon continued freedom of the West Coast of Mexico and of Northwest Mexico from infestations...

  3. 7 CFR 319.8-12 - From the West Coast of Mexico.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 5 2011-01-01 2011-01-01 false From the West Coast of Mexico. 319.8-12 Section 319.8... Conditions for the Entry of Cotton and Covers from Mexico § 319.8-12 From the West Coast of Mexico. Contingent upon continued freedom of the West Coast of Mexico and of Northwest Mexico from infestations...

  4. 7 CFR 319.8-12 - From the West Coast of Mexico.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 5 2013-01-01 2013-01-01 false From the West Coast of Mexico. 319.8-12 Section 319.8... Conditions for the Entry of Cotton and Covers from Mexico § 319.8-12 From the West Coast of Mexico. Contingent upon continued freedom of the West Coast of Mexico and of Northwest Mexico from infestations...

  5. 7 CFR 319.8-12 - From the West Coast of Mexico.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 5 2014-01-01 2014-01-01 false From the West Coast of Mexico. 319.8-12 Section 319.8... Conditions for the Entry of Cotton and Covers from Mexico § 319.8-12 From the West Coast of Mexico. Contingent upon continued freedom of the West Coast of Mexico and of Northwest Mexico from infestations...

  6. 7 CFR 319.8-12 - From the West Coast of Mexico.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 5 2012-01-01 2012-01-01 false From the West Coast of Mexico. 319.8-12 Section 319.8... Conditions for the Entry of Cotton and Covers from Mexico § 319.8-12 From the West Coast of Mexico. Contingent upon continued freedom of the West Coast of Mexico and of Northwest Mexico from infestations...

  7. Experimental characterization of West African Newcastle disease virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Four West African strains and one South African strain of virulent Newcastle disease virus (NDV) were characterized through a two-phase experiment. Strains investigated were Burkina Faso/2415-580/2008, Nigeria/228-7/2006, Niger/1377/2006, and Goose/South Africa/08100426/2008. Phylogenetic analysis s...

  8. On the summer coast parallel winds off the west coast of Iberia

    NASA Astrophysics Data System (ADS)

    Rijo, Nádia; Lima, Daniela C. A.; Semedo, Alvaro; Soares, Pedro M. M.; Cardoso, Rita M.; Miranda, Pedro M. A.

    2016-04-01

    During summer the west coast of the Iberian Peninsula is under the effect of persistent coast parallel northerly winds, called Nortada (northerly wind in Portuguese). The synoptic forcing behind the Nortada is caused by the semi-permanent Azores High and the thermal low pressure system in-land central Iberia. The associated pressure gradient gives rise to coastal parallel winds as the result of the geostrophically adjusted response to this synoptic pattern. In turn the persistence of the Nortada induces the development of upwelling systems from the Galicia to Algarve, off the west coast of Iberia, bringing deep cold nutrient-rich water to the shelf and to the surface. This cold water sharpens the temperature and pressure gradients at the coast, leading to a further increase of the wind speed at the coast. The summer regional climate of the coastal western Iberian area is modulated by the Nortada. The structure and climatology characterization of the summer Nortada is investigated through analyses of close to surface wind data produced by a regional 9km horizontal resolution atmospheric hindcast. This regional data was produced using the WRF model, forced by the ECMWF (European Centre for Medium-Range Weather Forecasts) ERA-Interim reanalysis, and covers the period 1989-2007. The link between the Nortada and the Iberian coastal low level jet is also studied.

  9. Relationships among obesity, inflammation, and insulin resistance in African Americans and West Africans.

    PubMed

    Doumatey, Ayo P; Lashley, Kerrie S; Huang, Hanxia; Zhou, Jie; Chen, Guanjie; Amoah, Albert; Agyenim-Boateng, Kofi; Oli, Johnnie; Fasanmade, Olufemi; Adebamowo, Clement A; Adeyemo, Adebowale A; Rotimi, Charles N

    2010-03-01

    Several research studies in different populations indicate that inflammation may be the link between obesity and insulin resistance (IR). However, this relationship has not been adequately explored among African Americans, an ethnic group with disproportionately high rates of obesity and IR. In this study, we conducted a comparative study of the relationship among adiposity, inflammation, and IR in African Americans and West Africans, the ancestral source population for African Americans. The associations between obesity markers (BMI and waist-to-hip ratio (WHR)), inflammatory markers (high-sensitivity C-reactive protein (hsCRP), haptoglobin, interleukin (IL)-6, and tumor necrosis factor (TNF)-alpha), and IR (homeostasis model assessment of insulin resistance (HOMA(IR))) were evaluated in 247 West Africans and 315 African Americans. In average, African Americans were heavier than the West Africans (by an average of 1.6 BMI units for women and 3 BMI units for men). Plasma hsCRP, haptoglobin, and IL-6 (but not TNF-alpha level) were higher in African Americans than in West Africans. In both populations, BMI was associated with markers of inflammation and with HOMA(IR), and these associations remained significant after adjusting for sex and age. However, the pattern of associations between measured inflammatory markers and IR was different between the two groups. In West Africans, hsCRP was the only inflammatory marker associated with IR. In contrast, hsCRP, haptoglobin, and IL-6 were all associated with IR in African Americans. Interestingly, none of the associations between markers of inflammation and IR remained significant after adjusting for BMI. This finding suggests that in African Americans, the relationship between inflammatory markers and IR is mediated by adiposity.

  10. 75 FR 51183 - Fisheries Off West Coast States; Modifications of the West Coast Commercial and Recreational...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-19

    .... SUPPLEMENTARY INFORMATION: In the 2010 annual management measures for ocean salmon fisheries (75 FR 24482, May 5... the annual management measures for ocean salmon fisheries (75 FR 24482, May 5, 2010), the West...

  11. 75 FR 75639 - Fisheries Off West Coast States; Modifications of the West Coast Commercial and Recreational...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-06

    .... SUPPLEMENTARY INFORMATION: In the 2010 annual management measures for ocean salmon fisheries (75 FR 24482, May 5... the annual management measures for ocean salmon fisheries (75 FR 24482, May 5, 2010), the West...

  12. Mitogenome revealed multiple postdomestication genetic mixtures of West African sheep.

    PubMed

    Brahi, O H D; Xiang, H; Chen, X; Farougou, S; Zhao, X

    2015-10-01

    Notable diversity observed within African ovine breeds makes them of great interests, but limited studies on genetic origins and domestications remain poorly understood. Here, we investigate the evolutionary status of West African native breeds, Djallonke and Sahelian sheep using mitogenome sequencing. Compared with other ovine mitogenome sequences, West African sheep were revealed a Eurasian origin, and the initially tamed sheep breeds in West Africa have been genetically mixed with each other and mixed with European breeds. Worldwide domestic sheep is deemed the Eurasian origin and migrated west to Europe and Africa and east to the Far East, in which dispersed and received selection for acclimation to autochthonic environment independently and ultimately evolved into different native breeds, respectively. Our results contribute to the comprehensive understanding of the domestic sheep origin and reveal multiple postdomestication genetic amelioration processes.

  13. 78 FR 2254 - Fisheries Off West Coast States and in the Western Pacific; Pacific Coast Groundfish Fishery...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-10

    ... National Oceanic and Atmospheric Administration RIN 0648-XC397 Fisheries Off West Coast States and in the Western Pacific; Pacific Coast Groundfish Fishery; Application for an Exempted Fishing Permit AGENCY... INFORMATION: This action is authorized by the Pacific Coast Groundfish Fishery Management Plan (FMP) and...

  14. ARkStorm: A West Coast Storm Scenario

    NASA Astrophysics Data System (ADS)

    Cox, D. A.; Jones, L. M.; Ralph, F. M.; Dettinger, M. D.; Porter, K.; Perry, S. C.; Barnard, P. L.; Hoover, D.; Wills, C. J.; Stock, J. D.; Croyle, W.; Ferris, J. C.; Plumlee, G. S.; Alpers, C. N.; Miller, M.; Wein, A.; Rose, A.; Done, J.; Topping, K.

    2009-12-01

    The United Stated Geological Survey (USGS) Multi-Hazards Demonstration Project (MHDP) is preparing a new emergency-preparedness scenario, called ARkStorm, to address massive U.S. West Coast storms analogous to those that devastated California in 1861-62. Storms of this magnitude are projected to become more frequent and intense as a result of climate change. The MHDP has assembled experts from the National Oceanic and Atmospheric Administration (NOAA), USGS, Scripps Institute of Oceanography, the State of California, California Geological Survey, the University of Colorado, the National Center for Atmospheric Research, and other organizations to design the large, but scientifically plausible, hypothetical scenario storm that would provide emergency responders, resource managers, and the public a realistic assessment of what is historically possible. The ARkStorm patterns the 1861 - 1862 historical events but uses modern modeling methods and data from large storms in 1969 and 1986. The ARkStorm draws heat and moisture from the tropical Pacific, forming Atmospheric Rivers (ARs) that grow in size, gain speed, and with a ferocity equal to hurricanes, slam into the U.S. West Coast for several weeks. Using sophisticated weather models and expert analysis, precipitation, snowlines, wind, and pressure data the modelers will characterize the resulting floods, landslides, and coastal erosion and inundation. These hazards will then be translated into the infrastructural, environmental, agricultural, social, and economic impacts. Consideration will be given to catastrophic disruptions to water supplies resulting from impacts on groundwater pumping, seawater intrusion, water supply degradation, and land subsidence. Possible climate-change forces that could exacerbate the problems will also be evaluated. In contrast to the recent U.S. East and Gulf Coast hurricanes, only recently have scientific and technological advances documented the ferocity and strength of possible future

  15. Tsunami Preparedness Along the U.S. West Coast (video)

    USGS Publications Warehouse

    Filmed and edited by: Loeffler, Kurt; Gesell, Justine

    2010-01-01

    Tsunamis are a constant threat to the coasts of our world. Although tsunamis are infrequent along the West coast of the United States, it is possible and necessary to prepare for potential tsunami hazards to minimize loss of life and property. Community awareness programs are important, as they strive to create an informed society by providing education and training. This video about tsunami preparedness along the West coast distinguishes between a local tsunami and a distant event and focuses on the specific needs of each region. It offers guidelines for correct tsunami response and community preparedness from local emergency managers, first-responders, and leading experts on tsunami hazards and warnings, who have been working on ways of making the tsunami affected regions safer for the people and communities on a long-term basis. This video was produced by the US Geological Survey (USGS) in cooperation with the California Emergency Management Agency (CalEMA), Oregon Department of Geology and Mineral Industries (DOGAMI), Washington Emergency Management Division (EMD), Marin Office of Emergency Services, and Pacific Gas and Electric (PG&E).

  16. 33 CFR 100.1305 - Richland, Washington, west coast outboard championship hydro races.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Richland, Washington, west coast outboard championship hydro races. 100.1305 Section 100.1305 Navigation and Navigable Waters COAST GUARD... Richland, Washington, west coast outboard championship hydro races. (a) Regulated area. By this...

  17. 33 CFR 100.1305 - Richland, Washington, west coast outboard championship hydro races.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Richland, Washington, west coast outboard championship hydro races. 100.1305 Section 100.1305 Navigation and Navigable Waters COAST GUARD... Richland, Washington, west coast outboard championship hydro races. (a) Regulated area. By this...

  18. 40 CFR 408.190 - Applicability; description of the West Coast mechanized salmon processing subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Coast mechanized salmon processing subcategory. 408.190 Section 408.190 Protection of Environment... PROCESSING POINT SOURCE CATEGORY West Coast Mechanized Salmon Processing Subcategory § 408.190 Applicability; description of the West Coast mechanized salmon processing subcategory. The provisions of this subpart...

  19. 40 CFR 408.190 - Applicability; description of the West Coast mechanized salmon processing subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Coast mechanized salmon processing subcategory. 408.190 Section 408.190 Protection of Environment... PROCESSING POINT SOURCE CATEGORY West Coast Mechanized Salmon Processing Subcategory § 408.190 Applicability; description of the West Coast mechanized salmon processing subcategory. The provisions of this subpart...

  20. 40 CFR 408.190 - Applicability; description of the West Coast mechanized salmon processing subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Coast mechanized salmon processing subcategory. 408.190 Section 408.190 Protection of Environment... PROCESSING POINT SOURCE CATEGORY West Coast Mechanized Salmon Processing Subcategory § 408.190 Applicability; description of the West Coast mechanized salmon processing subcategory. The provisions of this subpart...

  1. 40 CFR 408.190 - Applicability; description of the West Coast mechanized salmon processing subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Coast mechanized salmon processing subcategory. 408.190 Section 408.190 Protection of Environment... PROCESSING POINT SOURCE CATEGORY West Coast Mechanized Salmon Processing Subcategory § 408.190 Applicability; description of the West Coast mechanized salmon processing subcategory. The provisions of this subpart...

  2. 40 CFR 408.190 - Applicability; description of the West Coast mechanized salmon processing subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Coast mechanized salmon processing subcategory. 408.190 Section 408.190 Protection of Environment... PROCESSING POINT SOURCE CATEGORY West Coast Mechanized Salmon Processing Subcategory § 408.190 Applicability; description of the West Coast mechanized salmon processing subcategory. The provisions of this subpart...

  3. 33 CFR 100.1305 - Richland, Washington, west coast outboard championship hydro races.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Richland, Washington, west coast outboard championship hydro races. 100.1305 Section 100.1305 Navigation and Navigable Waters COAST GUARD... Richland, Washington, west coast outboard championship hydro races. (a) Regulated area. By this...

  4. 33 CFR 100.1305 - Richland, Washington, west coast outboard championship hydro races.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Richland, Washington, west coast outboard championship hydro races. 100.1305 Section 100.1305 Navigation and Navigable Waters COAST GUARD... Richland, Washington, west coast outboard championship hydro races. (a) Regulated area. By this...

  5. Assessment of undiscovered oil and gas resources of the West African Costal Province, West Africa

    USGS Publications Warehouse

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

    2011-01-01

    The West African Coastal Province along the west African coastline recently was assessed for undiscovered, technically recoverable oil, natural gas, and natural gas liquids resources as part of the U.S. Geological Survey's USGS World Oil and Gas Assessment. Using a geology-based assessment methodology, the USGS estimated mean volumes of 3.2 billion barrels of oil, 23.63 trillion cubic feet of natural gas, and 721 million barrels of natural gas liquids.

  6. 77 FR 55426 - Fisheries Off West Coast States; Modifications of the West Coast Commercial and Recreational...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-10

    ... INFORMATION: Background In the 2012 annual management measures for ocean salmon fisheries (77 FR 25915, May 2... to May 1, 2013 (77 FR 25915, May 2, 2012). The RA determined that the best available information... the annual management measures for ocean salmon fisheries (77 FR 25915, May 2, 2012), the West...

  7. 77 FR 65329 - Fisheries Off West Coast States; Modifications of the West Coast Commercial and Recreational...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-26

    ... measures for ocean salmon fisheries (77 FR 25915, May 2, 2012), NMFS announced the commercial and... regulations remain in effect as announced for the 2012 Ocean Salmon Fisheries (77 FR 25915, May 2, 2012) and... the annual management measures for ocean salmon fisheries (77 FR 25915, May 2, 2012), the West...

  8. 77 FR 61728 - Fisheries Off West Coast States; Modifications of the West Coast Commercial and Recreational...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-11

    ...: Background In the 2012 annual management measures for ocean salmon fisheries (77 FR 25915, May 2, 2012), NMFS... as announced for the 2012 Ocean Salmon Fisheries (77 FR 25915, May 2, 2012) and subsequent inseason... the annual management measures for ocean salmon fisheries (77 FR 25915, May 2, 2012), the West...

  9. East African coast overlooked. [Oil and gas potential of the east African coast

    SciTech Connect

    Not Available

    1994-09-01

    This paper reviews the petroleum and gas potential of the Tanzania-Mozambique basinal areas. It discusses the locations of the various sedimentary basins in the onshore and near offshore areas, including the central African rift zone. The paper describes the structure, stratigraphy, and petroleum geology of these basins. Finally the paper reviews the exploration history and the outlook for the future of these basins.

  10. Bias reduction in decadal predictions of West African monsoon rainfall using regional climate models

    NASA Astrophysics Data System (ADS)

    Paxian, A.; Sein, D.; Panitz, H.-J.; Warscher, M.; Breil, M.; Engel, T.; Tödter, J.; Krause, A.; Cabos Narvaez, W. D.; Fink, A. H.; Ahrens, B.; Kunstmann, H.; Jacob, D.; Paeth, H.

    2016-02-01

    The West African monsoon rainfall is essential for regional food production, and decadal predictions are necessary for policy makers and farmers. However, predictions with global climate models reveal precipitation biases. This study addresses the hypotheses that global prediction biases can be reduced by dynamical downscaling with a multimodel ensemble of three regional climate models (RCMs), a RCM coupled to a global ocean model and a RCM applying more realistic soil initialization and boundary conditions, i.e., aerosols, sea surface temperatures (SSTs), vegetation, and land cover. Numerous RCM predictions have been performed with REMO, COSMO-CLM (CCLM), and Weather Research and Forecasting (WRF) in various versions and for different decades. Global predictions reveal typical positive and negative biases over the Guinea Coast and the Sahel, respectively, related to a southward shifted Intertropical Convergence Zone (ITCZ) and a positive tropical Atlantic SST bias. These rainfall biases are reduced by some regional predictions in the Sahel but aggravated by all RCMs over the Guinea Coast, resulting from the inherited SST bias, increased westerlies and evaporation over the tropical Atlantic and shifted African easterly waves. The coupled regional predictions simulate high-resolution atmosphere-ocean interactions strongly improving the SST bias, the ITCZ shift and the Guinea Coast and Central Sahel precipitation biases. Some added values in rainfall bias are found for more realistic SST and land cover boundary conditions over the Guinea Coast and improved vegetation in the Central Sahel. Thus, the ability of RCMs and improved boundary conditions to reduce rainfall biases for climate impact research depends on the considered West African region.

  11. West African warming: Investigating Temperature Trends and their relation between Precipitation Trends over West African Sahel.

    NASA Astrophysics Data System (ADS)

    LY, M., Jr.

    2014-12-01

    It is now admitted that the West African region faces a lot of constraints due to the comprehensiveness of the high climate variability and potential climate change. This is mainly due to the lack of a large number of datasets and long-term records as summarized in the in the IPCC reports. This paper aims to provide improved knowledge and evidence on current and future climate conditions, for better manage climate variability over seasons and from year to year and strengthen the capacity to adapt to future climate change. In this regards, we analyse the evolution of some extreme temperature and precipitation indices over a large area of West Africa. Prior results show a general warming trend at individual stations throughout the region during the period from 1960 to 2010, namely negative trends in the number of cool nights, and positive trends in the number of warm days and length of warm spells. Trends in rainfall-related indices are not as uniform as the ones in temperatures, rather they display marked multi-decadal variability, as expected. To refine analyses of temperature variations and their relation to precipitation we investigated on cluster analysis aimed at distinguishing different sub-regions, such as continental and coastal, and relevant seasons, such as wet, dry/cold and dry warm. This will contribute to significantly lower uncertainties by developing better and more tailored temperature and precipitation trends to inform the user communities on climate related risks, as well as enhance their resilience to food insecurity and other climate related disasters.

  12. 75 FR 4684 - Fisheries off West Coast States; Pacific Coast Groundfish Fishery; Data Collection for the Trawl...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-29

    ...' Northwest Fisheries Science Center's Pacific whiting observer data from NORPAC (a database of North Pacific... Commission's PacFIN database and NMFS' Northwest Fisheries Science Center's Pacific whiting observer data... West Coast States; Pacific Coast Groundfish Fishery; Data Collection for the Trawl...

  13. 75 FR 12729 - Fisheries Off West Coast States and in the Western Pacific; Pacific Coast Groundfish Fishery...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-17

    ... From the Federal Register Online via the Government Publishing Office ] DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration RIN 0648-XU95 Fisheries Off West Coast States and in the Western Pacific; Pacific Coast Groundfish Fishery; Application for an Exempted Fishing Permit...

  14. Understanding the mechanisms behind the West African Monsoon northward extension during Mid-Holocene

    NASA Astrophysics Data System (ADS)

    Gaetani, Marco; Messori, Gabriele; Zhang, Qiong; Flamant, Cyrille; Evan, Amato T.; Pausata, Francesco S. R.

    2016-04-01

    Understanding the West African monsoon (WAM) dynamics in the mid-Holocene (MH) is a crucial issue in climate modelling, because numerical models typically fail to reproduce the extensive precipitation suggested by proxy evidence. This discrepancy is largely due to unrealistic imposed land surface cover and aerosols. Numerical experiments are conducted by imposing a "green Sahara", along with a reduced dust concentration in the atmosphere, coherently with the MH environment in the region, and the atmospheric dynamics response and impact on precipitation are investigated. The response of the WAM system to the imposed conditions shows a dramatic augmentation of the precipitation across West Africa up to the Mediterranean coast. This follows a substantial reorganization of the regional circulation, with some monsoonal circulation features (Saharan heat low, African easterly jet, African easterly waves) weakened in favour of deep convection development over land. The simulated response is dominated by land cover changes, and the reduction in dust concentration further enhances the changes induced by the "green Sahara". The intensity and meridional extent of the WAM is fully consistent with proxy evidence. The results for the MH WAM present important implications for understanding future climate scenarios in the region, in the perspective of projected wetter conditions in West Africa.

  15. Assessing the contributions of East African and West Pacific warming to the 2014 boreal spring East African drought

    USGS Publications Warehouse

    Funk, Christopher C.; Shukla, Shraddhanand; Hoell, Andrew; Livneh, Ben

    2015-01-01

    Anthropogenic warming contributed to the 2014 East African drought by increasing East African and west Pacific temperatures, and increasing the gradient between standardized western and central Pacific SST causing reduced rainfall, evapotranspiration, and soil moisture.

  16. Holocene Glacial Retreat at Walgreen Coast, West Antarctica

    NASA Astrophysics Data System (ADS)

    Lindow, J.; Johnson, J.; Castex, M.; Wittmann, H.; Smith, J.; Lisker, F.; Gohl, K.; Spiegel, C.

    2012-12-01

    The Walgreen Coast of West Antarctica represents one of the most rapidly changing sectors of the West Antarctic Ice Sheet (WAIS). With the fastest ice streams in the whole Antarctic, the WAIS is characterised by rapid thinning and grounding line retreat. Airborne and satellite-based short-term observations show a doubling of the negative net mass balance between 1996-2006 (Rignot et al., 2008). Furthermore, because the WAIS is largely grounded below sea level, continued inland thinning and grounding line retreat could result in rapid ice sheet collapse, which would raise global sea level by between 3-5 m. However, due to remoteness and challenging accessibility, onshore data is limited to a few isolated nunataks making it difficult to assess the long-term evolution of the glacial dynamics along Walgreen Coast. To address this we present new data from two key areas of the Walgreen Coast; the Kohler Range and the Pine Island Bay. Our 10Be surface exposure ages from erratic boulders in the Kohler Range are the first and reveal that this area became ice-free between 8.3 and 12.3 ka. This implies a long-term thinning rate of 3.3 cm/yr and agrees with similar data published from glaciers eastward. Our ages are also consistent with recent deglaciation models which suggest strong thinning after 15 ka and off-shore sediments shows a concurrent lateral ice-shelf front retreat. Our results suggest an ice-cover at least 300 m thicker in the Kohler Range during the early Holocene and that subsequent average thinning occurred on rates one order of magnitude slower than recent satellite measurements show. This implies that the recent trend in ice-sheet thinning results from a recent dynamic changes rather than a response to long-term thinning. To further constrain the lateral deglaciation history along the eastern Walgreen Coast, namely the Pine Island Glacier, we collected additional samples from a chain of islands, located flow-parallel and downstream of the ice-shelf front. We

  17. History of petroleum exploration in California and the West Coast

    SciTech Connect

    Kilkenny, J.E.

    1991-03-01

    California's main oil and gas basins consist of the inland Sacramento and San Joaquin and the Los Angeles, Ventura, and Santa Maria basins adjacent to the coast and extending offshore. The state's total oil production to 1991 is approximately 22.8 billion bbls. Producing formations range in age from basement Jurassic to Pleistocene, but production is mainly from thick multiple sand zones of Miocene and Pliocene age. The first oil discovery was in the eastern Ventura basin in 1875. By the turn of the century, 22 fields, including several giants in the San Joaquin Valley, had been discovered by drilling near oil seepages. The most important event of the 1920s was the discovery of several giant oil fields in the Los Angeles basin, drilled on topographic highs suggestive of underlying anticlines. State production rapidly increased to 850,000 BOPD, or 40% of all US production. The 1930s saw the advent of the reflection seismograph, responsible for the state's largest oil field (Wilmington) in the Lost Angeles basin and the state's largest gas field (Rio Vista) in the Sacramento basin. A number of important fields were found under the San Joaquin Valley floor. Geological thinking in the late 1930s and 1940s resulted in the discovery of large stratigraphic traps in the San Joaquin Valley (e.g., East Coalinga) and at Santa Maria from fractured shale, plus two new small producing basins, the Cuyama and the Salinas. Offshore exploration, consisting of seismic work, ocean-bottom sampling, and coreholing, revealed the presence of a number of anticlines in the Ventura basin, paralleling the Santa Barbara coast. The first offshore discovery was made in 1959 on state lands followed by several major fields on federal lands in the late 1960s. Elsewhere along the West Coast, exploration in Oregon and Washington has yielded only minor gas.

  18. Influence of 21st century atmospheric and sea surface temperature forcing on West African climate

    SciTech Connect

    Skinner, Chris B; Ashfaq, Moetasim; Diffenbaugh, Noah

    2011-01-01

    he persistence of extended drought events throughout West Africa during the 20th century has motivated a substantial effort to understand the mechanisms driving African climate variability, as well as the possible response to elevated greenhouse gas (GHG) forcing. We use an ensemble of global climate model experiments to examine the relative roles of future direct atmospheric radiative forcing and SST forcing in shaping potential future changes in boreal summer precipitation over West Africa. We find that projected increases in precipitation throughout the Western Sahel result primarily from direct atmospheric radiative forcing. The changes in atmospheric forcing generate a slight northward displacement and weakening of the African easterly jet (AEJ), a strengthening of westward monsoon flow onto West Africa and an intensification of the tropical easterly jet (TEJ). Alternatively, we find that the projected decreases in precipitation over much of the Guinea Coast region are caused by SST changes that are induced by the atmospheric radiative forcing. The changes in SSTs generate a weakening of the monsoon westerlies and the TEJ, as well as a decrease in low-level convergence and resultant rising air throughout the mid levels of the troposphere. Our experiments suggest a potential shift in the regional moisture balance of West Africa should global radiative forcing continue to increase, highlighting the importance of climate system feedbacks in shaping the response of regional-scale climate to global-scale changes in radiative forcing.

  19. Strong association between west african rainfall and u.s. Landfall of intense hurricanes.

    PubMed

    Gray, W M

    1990-09-14

    Intense hurricanes occurred much more frequently during the period spanning the late 1940s through the late 1960s than during the 1970s and 1980s, except for 1988 and 1989. Seasonal and multidecadal variations of intense hurricane activity are closely linked to seasonal and multidecadal variations of summer rainfall amounts in the Western Sahel region of West Africa. The multidecadal nature of West African precipitation variations and their association with variations of intense Atlantic hurricane activity can be observed in data going back nearly a century. The apparent recent breaking of the 18-year Sahel drought during 1988 and 1989 suggests that the incidence of intense hurricanes making landfall on the U.S. coast and in the Caribbean basin will likely increase during the 1990s and early years of the 21st century to levels of activity notably greater than were observed during the 1970s and 1980s.

  20. Phylogenetic Relationships of Southern African West Nile Virus Isolates

    PubMed Central

    Grobbelaar, Antoinette A.; Leman, Patricia A.; Anthony, Fiona S.; Gibson, Georgina V.F.; Swanepoel, Robert

    2002-01-01

    Phylogenetic relationships were examined for 29 southern African West Nile virus (formal name West Nile virus [WNV]) isolates from various sources in four countries from 1958 to 2001. In addition sequence data were retrieved from GenBank for another 23 WNV isolates and Kunjin and Japanese encephalitis viruses. All isolates belonged to two lineages. Lineage 1 isolates were from central and North Africa, Europe, Israel, and North America; lineage 2 isolates were from central and southern Africa and Madagascar. No strict correlation existed between grouping and source of virus isolate, pathogenicity, geographic distribution, or year of isolation. Some southern African isolates have been associated with encephalitis in a human, a horse, and a dog and with fatal hepatitis in a human and death of an ostrich chick. PMID:12141968

  1. Preliminary Geologic Characterization of West Coast States for Geologic Sequestration

    SciTech Connect

    Larry Myer

    2005-09-29

    Characterization of geological sinks for sequestration of CO{sub 2} in California, Nevada, Oregon, and Washington was carried out as part of Phase I of the West Coast Regional Carbon Sequestration Partnership (WESTCARB) project. Results show that there are geologic storage opportunities in the region within each of the following major technology areas: saline formations, oil and gas reservoirs, and coal beds. The work focused on sedimentary basins as the initial most-promising targets for geologic sequestration. Geographical Information System (GIS) layers showing sedimentary basins and oil, gas, and coal fields in those basins were developed. The GIS layers were attributed with information on the subsurface, including sediment thickness, presence and depth of porous and permeable sandstones, and, where available, reservoir properties. California offers outstanding sequestration opportunities because of its large capacity and the potential of value-added benefits from enhanced oil recovery (EOR) and enhanced gas recovery (EGR). The estimate for storage capacity of saline formations in the ten largest basins in California ranges from about 150 to about 500 Gt of CO{sub 2}, depending on assumptions about the fraction of the formations used and the fraction of the pore volume filled with separate-phase CO{sub 2}. Potential CO{sub 2}-EOR storage was estimated to be 3.4 Gt, based on a screening of reservoirs using depth, an API gravity cutoff, and cumulative oil produced. The cumulative production from gas reservoirs (screened by depth) suggests a CO{sub 2} storage capacity of 1.7 Gt. In Oregon and Washington, sedimentary basins along the coast also offer sequestration opportunities. Of particular interest is the Puget Trough Basin, which contains up to 1,130 m (3,700 ft) of unconsolidated sediments overlying up to 3,050 m (10,000 ft) of Tertiary sedimentary rocks. The Puget Trough Basin also contains deep coal formations, which are sequestration targets and may have

  2. "Speaking a Secret Language:" West Coast Swing as a Community of Practice of Informal and Incidental Learners

    ERIC Educational Resources Information Center

    Callahan, Jamie L.

    2005-01-01

    This study reports the findings of a qualitative study of competitive West Coast Swing dancers that incorporated both ethnographic and phenomenological techniques. A modern variation of the original Lindy Hop, West Coast Swing is typically learned in dance studios and non-profit clubs. The West Coast Swing community can be considered a community…

  3. 50 CFR Table 3 to Part 660, Subpart C - Vessel Capacity Ratings for West Coast Groundfish Limited Entry Permits

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 13 2013-10-01 2013-10-01 false Vessel Capacity Ratings for West Coast...) FISHERIES OFF WEST COAST STATES Pt. 660, Subpt. C, Table 3 Table 3 to Part 660, Subpart C—Vessel Capacity Ratings for West Coast Groundfish Limited Entry Permits Vessel length Capacity rating 400 311.80...

  4. Exploring female genital cutting among west African immigrants.

    PubMed

    Akinsulure-Smith, Adeyinka M

    2014-06-01

    Although many African women immigrate to the United States from countries with high prevalence rates for female genital cutting (FGC), there has been limited research exploring the incidence and impact of FGC among this growing immigrant population. This pilot study sought to examine the experiences of FGC among West African immigrant women in the US. Of the 23 participants, 7 reported a history of FGC, with Muslim participants reporting significantly higher rates of FGC than Christians (Fisher's Exact = .045). Most of the women who had experienced FGC were from Sierra Leone (Fisher's Exact = .027). Limitations of the study are discussed along with suggestions for future research aimed at understanding the impact of FGC, reducing the prevalence and demand for FGC among African immigrant women and improving the health and quality of life of women who have undergone the procedure.

  5. What rainfall events trigger landslides on the West Coast US?

    NASA Astrophysics Data System (ADS)

    Biasutti, Michela; Seager, Richard; Kirschbaum, Dalia

    2016-04-01

    A dataset of landslide occurrences compiled by collating google news reports covers 9 full years of data. We show that, while this compilation cannot provide consistent and widespread monitoring everywhere, it is adequate to capture the distribution of events in the major urban areas of the West Coast US and it can be used to provide a quantitative relationship between landslides and rainfall events. The case of the Seattle metropolitan area is presented as an example. The landslide dataset shows a clear seasonality in landslide occurrence, corresponding to the seasonality of rainfall, modified by the accumulation of soil moisture as winter progresses. Interannual variability of landslide occurrences is also linked to interannual variability of monthly rainfall. In most instances, landslides are clustered on consecutive days or at least within the same pentad and correspond to days of large rainfall accumulation at the regional scale. A joint analysis of the landslide data and of the high-resolution PRISM daily rainfall accumulation shows that on days when landslides occurred, the distribution of rainfall was shifted, with rainfall accumulation higher than 10mm/day being more common. Accumulations above 50mm/day much increase the probability of landslides, including the possibility of a major landslide event (one with multiple landslides in a day). The synoptic meteorological conditions associated with these major events show a mid-tropospheric ridge to the south of the target area steering a surface low and bringing enhanced precipitable water towards the Pacific North West. The interaction of the low-level flow with the local orography results in instances of a strong Puget Sound Convergence Zone, with widespread rainfall accumulation above 30mm/day and localized maxima as high as 100mm/day or more.

  6. Factors influencing the migration of West African health professionals

    PubMed Central

    Lowe, Mat; Chen, Duan-Rung

    2016-01-01

    Introduction The West African health sector is characterized by a human resource base lacking in numbers and specialized skills. Among the contributory factors to this lack of human resource for health workforce include but not limited to the migration of health professionals. Methods This cross-sectional survey targeted 118 young professionals who have participated in the Young Professional Internship Program (YPIP) of the West African Health Organization (WAHO), from (2005-2013). It inquired about their socio-demographic characteristics associated with migration and reasons for going to their preferred or most likely destinations through online survey. Results Of the 118 young professionals, 100 responded to the online survey, of which (28%) have migrated and (72%) did not migrate. Migration was more common among males and those (age≤31 years old), single with high dependency level and no previous work experience. Having a medical profession and being posted to urban or semi-urban area was also associated with their emigration. Their most important reasons for going to preferred or most likely destinations were to have fair level of workload, job promotion and limited occupational risks. Conclusion This finding suggests that the migration of health professionals is situation dependent, mediated by basic socio-demographic variables and work related conditions. These issues have implications for curbing the brain drain potential of health professionals in the West African health sector. PMID:27800092

  7. Back to Africa: Second Chances for the Children of West African Immigrants

    ERIC Educational Resources Information Center

    Bledsoe, Caroline H.; Sow, Papa

    2011-01-01

    This paper examines the phenomenon of West African parents living in Europe and North America who send their older children back home: from places of high immigrant aspiration to those of hardship and privation. Drawing on a project on West African immigration to Europe and on previous field studies in Africa, we conclude that West African…

  8. Dynamic Stability of Coral Reefs on the West Australian Coast

    PubMed Central

    Speed, Conrad W.; Babcock, Russ C.; Bancroft, Kevin P.; Beckley, Lynnath E.; Bellchambers, Lynda M.; Depczynski, Martial; Field, Stuart N.; Friedman, Kim J.; Gilmour, James P.; Hobbs, Jean-Paul A.; Kobryn, Halina T.; Moore, James A. Y.; Nutt, Christopher D.; Shedrawi, George; Thomson, Damian P.; Wilson, Shaun K.

    2013-01-01

    Monitoring changes in coral cover and composition through space and time can provide insights to reef health and assist the focus of management and conservation efforts. We used a meta-analytical approach to assess coral cover data across latitudes 10–35°S along the west Australian coast, including 25 years of data from the Ningaloo region. Current estimates of coral cover ranged between 3 and 44% in coral habitats. Coral communities in the northern regions were dominated by corals from the families Acroporidae and Poritidae, which became less common at higher latitudes. At Ningaloo Reef coral cover has remained relatively stable through time (∼28%), although north-eastern and southern areas have experienced significant declines in overall cover. These declines are likely related to periodic disturbances such as cyclones and thermal anomalies, which were particularly noticeable around 1998/1999 and 2010/2011. Linear mixed effects models (LME) suggest latitude explains 10% of the deviance in coral cover through time at Ningaloo. Acroporidae has decreased in abundance relative to other common families at Ningaloo in the south, which might be related to persistence of more thermally and mechanically tolerant families. We identify regions where quantitative time-series data on coral cover and composition are lacking, particularly in north-western Australia. Standardising routine monitoring methods used by management and research agencies at these, and other locations, would allow a more robust assessment of coral condition and a better basis for conservation of coral reefs. PMID:23922829

  9. Astronomy as Practiced in the West African City of Timbuktu

    NASA Astrophysics Data System (ADS)

    Medupe, Thebe Rodney

    Islam was introduced to West Africa over a millennium ago as a result of trade with North Africa and other parts of the Middle East. Islamic scholarship thrived in the city of Timbuktu in the fifteenth and sixteenth centuries. During this time West African scholars studied and taught mathematics, Quranic studies, and astronomy among other subjects. Until recently, the detail of what astronomy was known and practiced was not known. As an example of the content of material taught in the madrassas in West Africa, I present an outline of the content of two manuscripts written in the seventeenth century by Timbuktu scholars Muḥammad (or Aḥmad) b. Muḥammad Baghayu‛u b. Muḥammad Kūrdu and Abū l-‛Abbās Aḥmad b. al-Ḥājj R-mām-y-n al-Tuwātī al-Ghallāwī.

  10. 75 FR 33733 - Fisheries Off West Coast States; Coastal Pelagic Species Fisheries; Closure

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-15

    ... Fisheries Off West Coast States; Coastal Pelagic Species Fisheries; Closure AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA), Commerce. ACTION... as part of the live bait fishery or incidental to other fisheries; the incidental harvest of...

  11. Library Life on the West Coast. Part I: Local Color and Sweet Dreams

    ERIC Educational Resources Information Center

    Plotnik, Art

    1974-01-01

    A look at the color, style, dreams, and nightmares of several West Coast libraries, with particular emphasis on the Seattle, Los Angeles, and San Francisco areas. Brief notes on Southern California Answering Network and Bay Area Reference Center. (LS)

  12. Neogene molluscan stages of the West Coast of North America

    USGS Publications Warehouse

    Marincovich, L.

    1984-01-01

    Neogene marine sediments of the West Coast of North America were deposited in a series of widely spaced basins that extended geographically from the western and northern Gulf of Alaska (60??N) to southern California (33??N). Rich molluscan faunas occur extensively throughout these deposits and form the basis for biostratigraphic schemes that are useful for correlating within and between individual basins. Early biostratigraphic work was concerned with faunas from particular horizons and with the stratigraphic range of diverse taxa, such as Pecten and Turritella, without reference to other fossil groups. Succeeding work increasingly dealt with the relationships of molluscan zones to benthic and, later, planktonic foraminiferal stages. In recent years the age limits of Neogene molluscan stages have become better documented by reference to planktonic microfossils from dated DSDP cores and onshore faunas. Neogene molluscan faunas from California, the Pacific Northwest states (Oregon and Washington), and southern Alaska have been treated separately due to differences in faunal composition and geographic isolation. As a result, a different biostratigraphic sequence has been described for each region. Pacific Northwest stages have been formally named and defined, and their names are also used informally for Alaskan faunas. California Neogene stages were proposed early in this century, are in need of redescription, and their usage is informal. Precise correlations between the three regional sequences have not yet been achieved, due to the low number of co-occurring species and the general lack of planktonic microfossils in these largely shallow-water faunas. The objectives of ongoing research include: fuller documentation of the faunas of California and Pacific Northwest stages; formal description of California stages; improved correlation between regional stage sequences; refinement of age estimates for stage boundaries; and, establishment of Neogene stages for Alaskan

  13. Prevalence of Glaucoma in an Urban West African Population

    PubMed Central

    Budenz, Donald L.; Barton, Keith; Whiteside-de Vos, Julia; Schiffman, Joyce; Bandi, Jagadeesh; Nolan, Winifred; Herndon, Leon; Kim, Hanna; Hay-Smith, Graham; Tielsch, James M.

    2014-01-01

    Importance Multiple studies have found an increased prevalence, younger age at onset, and more severe course of glaucoma in people of African descent, but these findings are based on studies conducted outside Africa. Objective To determine the prevalence of glaucoma in an urban West African population of adults. Design and Setting A population-based, cross-sectional study of adults 40 years and older conducted from September 1, 2006, through December 31, 2008, from 5 communities in Tema, Ghana. Participants Participants from randomly selected clusters underwent a screening examination that consisted of visual acuity, frequency doubling perimetry, applanation tonometry, and optic disc photography. Participants who failed any of these tests were referred for complete examination, including gonioscopy, standard automated perimetry, and stereoscopic optic disc photography. Results A total of 6806 eligible participants were identified, and 5603 (82.3%) were enrolled in the study. The field examination referred 1869 participants (33.3%) to the clinic examination, and 1538 (82.2%) came for complete examination. A total of 362 participants were identified as having glaucoma of any type and category. Primary open-angle glaucoma was the underlying diagnosis in 342 participants (94.5%). The prevalence of primary open-angle glaucoma was 6.8% overall, increasing from 3.7% among those 40 to 49 years old to 14.6% among those 80 years and older, and was higher in men than in women in all age groups, with an overall male-female prevalence ratio of 1.5. Of the participants with glaucoma, 9 (2.5%) were blind using World Health Organization criteria, and only 12 (3.3%) were aware that they had glaucoma. Conclusions and Relevance The prevalence of glaucoma is higher in this urban West African population than in previous studies of people of East or South African and of non-African descent. Strategies to identify affected persons and effectively manage the burden of glaucoma are needed

  14. Will Elephants Soon Disappear from West African Savannahs?

    PubMed Central

    Bouché, Philippe; Douglas-Hamilton, Iain; Wittemyer, George; Nianogo, Aimé J.; Doucet, Jean-Louis; Lejeune, Philippe; Vermeulen, Cédric

    2011-01-01

    Precipitous declines in Africa's native fauna and flora are recognized, but few comprehensive records of these changes have been compiled. Here, we present population trends for African elephants in the 6,213,000 km2 Sudano-Sahelian range of West and Central Africa assessed through the analysis of aerial and ground surveys conducted over the past 4 decades. These surveys are focused on the best protected areas in the region, and therefore represent the best case scenario for the northern savanna elephants. A minimum of 7,745 elephants currently inhabit the entire region, representing a minimum decline of 50% from estimates four decades ago for these protected areas. Most of the historic range is now devoid of elephants and, therefore, was not surveyed. Of the 23 surveyed elephant populations, half are estimated to number less than 200 individuals. Historically, most populations numbering less than 200 individuals in the region were extirpated within a few decades. Declines differed by region, with Central African populations experiencing much higher declines (−76%) than those in West Africa (−33%). As a result, elephants in West Africa now account for 86% of the total surveyed. Range wide, two refuge zones retain elephants, one in West and the other in Central Africa. These zones are separated by a large distance (∼900 km) of high density human land use, suggesting connectivity between the regions is permanently cut. Within each zone, however, sporadic contacts between populations remain. Retaining such connectivity should be a high priority for conservation of elephants in this region. Specific corridors designed to reduce the isolation of the surveyed populations are proposed. The strong commitment of governments, effective law enforcement to control the illegal ivory trade and the involvement of local communities and private partners are all critical to securing the future of elephants inhabiting Africa's northern savannas. PMID:21731620

  15. Will elephants soon disappear from West African savannahs?

    PubMed

    Bouché, Philippe; Douglas-Hamilton, Iain; Wittemyer, George; Nianogo, Aimé J; Doucet, Jean-Louis; Lejeune, Philippe; Vermeulen, Cédric

    2011-01-01

    Precipitous declines in Africa's native fauna and flora are recognized, but few comprehensive records of these changes have been compiled. Here, we present population trends for African elephants in the 6,213,000 km² Sudano-Sahelian range of West and Central Africa assessed through the analysis of aerial and ground surveys conducted over the past 4 decades. These surveys are focused on the best protected areas in the region, and therefore represent the best case scenario for the northern savanna elephants. A minimum of 7,745 elephants currently inhabit the entire region, representing a minimum decline of 50% from estimates four decades ago for these protected areas. Most of the historic range is now devoid of elephants and, therefore, was not surveyed. Of the 23 surveyed elephant populations, half are estimated to number less than 200 individuals. Historically, most populations numbering less than 200 individuals in the region were extirpated within a few decades. Declines differed by region, with Central African populations experiencing much higher declines (-76%) than those in West Africa (-33%). As a result, elephants in West Africa now account for 86% of the total surveyed. Range wide, two refuge zones retain elephants, one in West and the other in Central Africa. These zones are separated by a large distance (∼900 km) of high density human land use, suggesting connectivity between the regions is permanently cut. Within each zone, however, sporadic contacts between populations remain. Retaining such connectivity should be a high priority for conservation of elephants in this region. Specific corridors designed to reduce the isolation of the surveyed populations are proposed. The strong commitment of governments, effective law enforcement to control the illegal ivory trade and the involvement of local communities and private partners are all critical to securing the future of elephants inhabiting Africa's northern savannas.

  16. The TG/HDL-C ratio does not predict insulin resistance in overweight women of African descent: a study of South African, African American and West African women.

    PubMed

    Knight, Michael G; Goedecke, Julia H; Ricks, Madia; Evans, Juliet; Levitt, Naomi S; Tulloch-Reid, Marshall K; Sumner, Anne E

    2011-01-01

    Women of African descent have a high prevalence of diseases caused by insulin resistance. To positively impact cardiometabolic health in Black women, effective screening tests for insulin resistance must be identified. Recently, the TG/HDL-C ratio has been recommended as a tool to predict insulin resistance in overweight people. While the ratio predicts insulin resistance in White women, it is ineffective in African American women. As there are no data for African women, we tested the ability of the TG/HDL-C ratio to predict insulin resistance in Black women from South Africa, West Africa and the United States. For comparison, the ratio was also tested in White women from South Africa. Participants were 801 women (157 Black South African, 382 African American, 119 West African, 143 White South African, age 36 +/- 9y [mean +/- SD]). Standardized scores were created from log-transformed homeostasis model assessment-insulin resistance values from each population. Participants in the upper third of their population distribution were classified as insulin-resistant. To predict insulin resistance by the TC/HDL-C ratio, area under the receiver operating characteristic (AUC-ROC) curve was used and criteria were: 0.50 for no discrimination and > or = 0.70 for acceptable. Seventy-one percent of the Black women were overweight vs 51% of White women (P<.01). In overweight White women, AUC-ROC curve for prediction of insulin resistance by TG/HDL-C was 0.76 +/- 0.06, but below the 0.70 threshold in each group of overweight Black women (Black South African: 0.64 +/- 0.06, African American: 0.66 +/- 0.03, and West African: 0.63 +/- 0.07). Therefore, TG/HDL-C does not predict insulin resistance in overweight African American women and this investigation extends that finding to overweight Black South African and West African women. Resources to identify effective markers of insulin resistance are needed to improve cardiometabolic health in women of African descent.

  17. Evaluation of Dynamics of the West African Monsoon Jump Simulated by the MIT Regional Climate Model

    NASA Astrophysics Data System (ADS)

    Eltahir, Elfatih A. B.; Im, Eun-Soon

    2015-04-01

    The seasonal advance and retreat of the West African monsoon behaves abrupt northward jump of maximum rainfall from the Guinean coast to the Sahel region. Both global and regional climate models have difficulties in accurately reproducing such a behavior due to its complexity combined the dynamical and physical processes. In this study, we evaluate the performance of the MIT Regional Climate Model (MRCM) in simulating the West African monsoon. For this, 20-year long-term simulation (1989-2008) is performed using the ERAInterim reanalysis as the initial and boundary condition, and the analysis primarily focuses on the dynamics associated with abrupt phase transitions of the monsoon rainfall. We first examine detailed characteristics in terms of the onset, maximum, and retreat of the monsoon rainfall using daily precipitation. We then present the dynamical explanation behind rainfall variability from the analysis of the absolute vorticity near the tropopause and the meridional gradient of boundary-layer entropy within the dynamical theory proposed by Eltahir and Gong (1996). Acknowledgements : This research was supported by the National Research Foundation Singapore through the Singapore MIT Alliance for Research and Technology's Center for Environmental Sensing and Modeling interdisciplinary research program.

  18. Future of West African Monsoon in A Warming Climate

    NASA Astrophysics Data System (ADS)

    Raj, Jerry; Kunhu Bangalath, Hamza; Stenchikov, Georgiy

    2016-04-01

    West Africa is the home of more than 300 million people whose agriculture based economy highly relies on West African Monsoon (WAM), which produces a mean annual rainfall of 150 - 2,500 mm and variability and change of which have devastating impact on the local population. The observed widespread drought in West Africa during the 1970s and 1980s was the most significant drought at regional scale during the twentieth century. In this study, a high resolution AGCM, High Resolution Atmospheric Model (HiRAM), is used to study the effects of anthropogenic greenhouse warming on WAM. HiRAM is developed at GFDL based on AM2 and employs a cubed-sphere finite volume dynamical core and uses shallow convective scheme (for moist convection and stratiform cloudiness) instead of deep convective parameterization. Future projections are done using two representative concentration pathways, RCP 4.5 and RCP 8.5 from 2007 to 2050 at C360 (~25 km) resolution. Both RCP 4.5 and RCP 8.5 scenarios predict warming over West Africa during boreal summer, especially over Western Sahara. Also, both scenarios predict southward shift in WAM rainfall pattern and drying over Southern Sahara, while RCP 8.5 predicts enhanced rainfall over Gulf of Guinea. The intensification of rainfall over tropical latitudes is caused by increased low level winds due to warm SST over Gulf of Guinea.

  19. 40 CFR 408.180 - Applicability; description of the West Coast hand-butchered salmon processing subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Coast hand-butchered salmon processing subcategory. 408.180 Section 408.180 Protection of Environment... PROCESSING POINT SOURCE CATEGORY West Coast Hand-Butchered Salmon Processing Subcategory § 408.180 Applicability; description of the West Coast hand-butchered salmon processing subcategory. The provisions...

  20. 40 CFR 408.180 - Applicability; description of the West Coast hand-butchered salmon processing subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Coast hand-butchered salmon processing subcategory. 408.180 Section 408.180 Protection of Environment... PROCESSING POINT SOURCE CATEGORY West Coast Hand-Butchered Salmon Processing Subcategory § 408.180 Applicability; description of the West Coast hand-butchered salmon processing subcategory. The provisions...

  1. 40 CFR 408.180 - Applicability; description of the West Coast hand-butchered salmon processing subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Coast hand-butchered salmon processing subcategory. 408.180 Section 408.180 Protection of Environment... PROCESSING POINT SOURCE CATEGORY West Coast Hand-Butchered Salmon Processing Subcategory § 408.180 Applicability; description of the West Coast hand-butchered salmon processing subcategory. The provisions...

  2. 40 CFR 408.180 - Applicability; description of the West Coast hand-butchered salmon processing subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Coast hand-butchered salmon processing subcategory. 408.180 Section 408.180 Protection of Environment... PROCESSING POINT SOURCE CATEGORY West Coast Hand-Butchered Salmon Processing Subcategory § 408.180 Applicability; description of the West Coast hand-butchered salmon processing subcategory. The provisions...

  3. 40 CFR 408.180 - Applicability; description of the West Coast hand-butchered salmon processing subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Coast hand-butchered salmon processing subcategory. 408.180 Section 408.180 Protection of Environment... PROCESSING POINT SOURCE CATEGORY West Coast Hand-Butchered Salmon Processing Subcategory § 408.180 Applicability; description of the West Coast hand-butchered salmon processing subcategory. The provisions...

  4. 50 CFR Table 2 to Part 660 - Vessel Capacity Ratings for West Coast Groundfish Limited Entry Permits

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Vessel Capacity Ratings for West Coast Groundfish Limited Entry Permits 2 Table 2 to Part 660 Wildlife and Fisheries FISHERY CONSERVATION AND... WEST COAST STATES Pt. 660, Table 2 Table 2 to Part 660—Vessel Capacity Ratings for West...

  5. 75 FR 67391 - Notice of Intent To Prepare a Draft Environmental Impact Statement for the West Coast Recycling...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-02

    ... Recycling Group Project in West Sacramento, Yolo County, CA AGENCY: Office of the Assistant Secretary for... Statement/Environmental Impact Report (EIS/EIR) for the development of the West Coast Recycling Group... West Coast Recycling Group (WCRG) proposes to develop approximately 15 acres at the Port of...

  6. English as a Second Language: An Educational Overview for Multicultural and Bilingual West African Students.

    ERIC Educational Resources Information Center

    Ubadigbo, Fidelis N.

    This paper describes cultural and educational characteristics of West African countries that may have implications for West Africans studying and learning English in the United States. Countries discussed include Nigeria, Ghana, Sierra Leone, Benin, Niger, Gambia, Senegal, Cote d'Ivoire, and Mali. The structures of the systems of elementary,…

  7. Spatial air pollution modelling for a West-African town.

    PubMed

    Gebreab, Sirak Zenebe; Vienneau, Danielle; Feigenwinter, Christian; Bâ, Hâmpaté; Cissé, Guéladio; Tsai, Ming-Yi

    2015-01-01

    Land use regression (LUR) modelling is a common approach used in European and Northern American epidemiological studies to assess urban and traffic related air pollution exposures. Studies applying LUR in Africa are lacking. A need exists to understand if this approach holds for an African setting, where urban features, pollutant exposures and data availability differ considerably from other continents. We developed a parsimonious regression model based on 48-hour nitrogen dioxide (NO2) concentrations measured at 40 sites in Kaédi, a medium sized West-African town, and variables generated in a geographic information system (GIS). Road variables and settlement land use characteristics were found to be important predictors of 48-hour NO2 concentration in the model. About 68% of concentration variability in the town was explained by the model. The model was internally validated by leave-one-out cross-validation and it was found to perform moderately well. Furthermore, its parameters were robust to sampling variation. We applied the model at 100 m pixels to create a map describing the broad spatial pattern of NO2 across Kaédi. In this research, we demonstrated the potential for LUR as a valid, cost-effective approach for air pollution modelling and mapping in an African town. If the methodology were to be adopted by environmental and public health authorities in these regions, it could provide a quick assessment of the local air pollution burden and potentially support air pollution policies and guidelines. PMID:26618306

  8. Monogeneans of West African Cichlid Fish: Evolution and Cophylogenetic Interactions

    PubMed Central

    Mendlová, Monika; Desdevises, Yves; Civáňová, Kristína; Pariselle, Antoine; Šimková, Andrea

    2012-01-01

    The goals of this paper were to investigate phylogenetic and evolutionary patterns of cichlid fish from West Africa and their Cichlidogyrus and Scutogyrus monogenean parasites, to uncover the presence of host-parasite cospeciation and to assess the level of morphological adaptation in parasites. This required the following steps, each one representing specific objectives of this paper: (1) to build phylogenetic trees for Cichlidogyrus and Scutogyrus species based on ribosomal DNA sequences, (2) to investigate phylogenetic relationships within West African cichlid fish based on the analysis of mitochondrial cytochrome b DNA sequences, (3) to investigate host-parasite cophylogenetic history to gain clues on parasite speciation process, and (4) to investigate the link between the morphology of the attachment apparatus and parasite phylogeny. Phylogenetic analyses supported the monophyletic origin of the Cichlidogyrus/Scutogyrus group, and suggested that Cichlidogyrus is polyphyletic and that Scutogyrus is monophyletic. The phylogeny of Cichlidae supported the separation of mouthbrooders and substrate-brooders and is consistent with the hypothesis that the mouthbrooding behavior of Oreochromis and Sarotherodon evolved from substrate-brooding behavior. The mapping of morphological characters of the haptor onto the parasite phylogenetic tree suggests that the attachment organ has evolved from a very simple form to a more complex one. The cophylogenetic analyses indicated a significant fit between trees using distance-based tests, but no significant cospeciation signal using tree-based tests, suggesting the presence of parasite duplications and host switches on related host species. This shed some light on the diversification process of Cichlidogyrus species parasitizing West African cichlids. PMID:22662139

  9. A PROBABILISTIC SURVEY OF SEDIMENT TOXICITY IN WEST COAST ESTUARIES

    EPA Science Inventory

    A probabalistic survey of coastal condition assessment was conducted in 1999 by participants in US EPA's Environmental Monitoring and Assessment Program (EMAP). The survey targeted estuaries along the outer coasts of Washington, Oregon and California, including the lower Columbi...

  10. 76 FR 77415 - Fisheries Off West Coast States; Pacific Coast Groundfish Fishery; 2012 Specifications and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-13

    ... States; Pacific Coast Groundfish Fishery; 2012 Specifications and Management Measures and Secretarial... specifications and management measures for certain groundfish species taken in the U.S. exclusive economic zone... Conservation and Management Act and the Pacific Coast Groundfish Fishery Management Plan (PCGFMP). This...

  11. Shelfbreak circulation, fronts and physical oceanography: east and west coast perspectives

    SciTech Connect

    Pietrafesa, L.J.

    1983-06-01

    A survey of fundamental physical oceanographic processes that may affect sediment distribution along shelfbreak regions is presented, emphasizing the Atlantic and Pacific coasts of the USA. These shelfbreak strips couple the bounded coastal oceans to the open seas, but there is no systematic pattern to this coupling. Pacific coast shelfbreak processes tend to be less energetic than those on the Atlantic coast since the Pacific coast is missing a Western Boundary Current and because the shelf is narrow and deep. Subinertial frequency shelfbreak motions on the west coast are typically manifested across the entire shelf, while those on the east coast tend to be confined to a loosely defined band, which brackets the break. Principal Pacific coast circulation elements include forms of continental shelf waves and thermohaline driven and mechanically wind forced currents, as well as the California Current System. While high frequency edge waves and inertial current are indigenous in similar fashion to all coasts, east and west coast tides are shown to be quite disparate, given tradeoffs between dominance of diurnal and semidiurnal constituents as a function of topographic constraint and strength of density stratification. All of the shelfbreak zones are graced by thermohaline fronts. The fronts are progradational on the west and southeastern coasts and retrogradational on the northeastern shelf. These fronts are an integral ingredient of all aspects of physical processes at the shelfbreak strip. The interplay of bottom topography with the physics of the outer continental margin is significant. Bottom features such as shoals, bumps, ridges and canyons are shown to be regions of sediment erosion, deposition and draping. Moreover, these features are shown to be casually related to upwelling and downwelling phenomena and to the deflection and scattering of waves and currents.

  12. Rehydration characteristics of dehydrated West African pepper (Piper guineense) leaves.

    PubMed

    Okpala, Laura C; Ekechi, Constance A

    2014-11-01

    The rehydration characteristics of dehydrated West African pepper leaves were investigated at hydration temperatures of 28, 60, 70, and 80°C. Four treatments were given to the leaves: blanched and sun dried, unblanched and sun dried, blanched and shade dried, and unblanched and shade dried. The hydration process of the dehydrated leaves was adequately described by the Peleg's equation. As the hydration temperature increased from 28 to 70°C, there was a significant decrease in the Peleg's constant K 1, while for most of the leaves the Peleg's constant K 2 varied with temperature. Rehydration ratio values ranged from 3.75 in blanched shade dried leaves to 4.26 in unblanched sun dried leaves with the unblanched leaves generally exhibiting higher ratios than the blanched leaves.

  13. The West African International Summer School for Young Astronomers

    NASA Astrophysics Data System (ADS)

    Strubbe, Linda; Okere, Bonaventure I.; Chibueze, James; Lepo, Kelly; White, Heidi; Zhang, Jielai; Izuikedinachi Okoh, Daniel; Reid, Michael; Hunter, Lisa; EKEOMA Opara, Fidelis

    2015-08-01

    In October 2013 over 75 undergraduate science students and teachers from Nigeria and Ghana attended the week-long West African International Summer School for Young Astronomers. We expect an even broader audience for the second offering of the school (to be held July 2015), supported by a grant from the OAD (TF1). These schools are organized by a collaboration of astronomers from the University of Toronto, the University of Nigeria, and the Nigerian National Space Research and Development Agency. We design and lead activities that teach astronomy content, promote students' self-identity as scientists, and encourage students to think critically and figure out solutions themselves. Equally important, we design intertwined evaluation strategies to assess the effectiveness of our programs. We will describe the broader context for developing astronomy in West Africa, the inquiry-based and active learning techniques used in the schools, and results from the qualitative and quantitative evaluations of student performance. We will also describe longer-term plans for future schools, supporting our alumni, and building a sustainable partnership between North American and Nigerian universities.

  14. Noma: experiences with a microvascular approach under West African conditions.

    PubMed

    Giessler, Goetz A; Schmidt, Andreas B

    2003-09-15

    Noma (cancrum oris) is a serious ulcerating disease that generally begins in the gingival sulcus of children. One of the main areas of prevalence today is West Africa. If noma is survived, it results in disfiguring midfacial defects and intense scarring. Oral incompetence is often combined with trismus resulting from scar formation or bony fusion between the maxilla and the mandible. Reconstructive approaches with pedicled flaps from the head or shoulder area for closure of the outer defects have been prone to donor-site complications or have not properly addressed the trismus, leading to high recurrence rates. During three West African Interplast missions, a single-stage procedure was developed for reconstruction of the inner and outer linings of the oral, nasal, and paranasal cavities, with restoration of jaw function. The procedure consists of radical scar excision, placement of an external distractor for mouth opening, and primary closure of the defect with a folded free parascapular flap for full-thickness coverage. Twenty-three patients with various noma-related defects were treated with this procedure; two cases are described in detail. This combined treatment can be a safe successful procedure for patients with noma, especially those with severe soft-tissue destruction and profound trismus, even under demanding surgical conditions.

  15. Pipeline hub project sets up gas service for U. S. West Coast markets

    SciTech Connect

    Murdock, P.J. )

    1990-08-06

    This paper reports how a major reconfiguration of a West Texas pipeline hub will allow the operator significant flexibility in transporting natural gas either to U.S. West Coast markets or to similar pipeline hubs in central and East Texas for movement to midwestern or eastern U.S. markets. The pipeline system is configured to transport natural gas between three major pipeline hubs in Texas: Carthage (Panola County), Katy (Waller County), and Waha (Pecos County).

  16. Higher Educational Needs of the Lower West Coast [Florida].

    ERIC Educational Resources Information Center

    Florida State Board of Regents, Tallahassee.

    This study reports the higher educational needs of the persons living in lower west Florida counties from Manatee to Collier, identifies the most feasible course of action to meet those needs and assesses the consequences ensuing from adding to the state university system. Chapters cover access to public higher education, expansion of the state…

  17. Assessing surface sediment dynamics along the north-west coast of Marsa Dhouiba (Tunisia, southern Mediterranean)

    NASA Astrophysics Data System (ADS)

    Khiari, Nouha; Atoui, Abdelfattah; Brahim, Mouldi; Sammari, Chérif; Charef, Abdelkrim; Aleya, Lotfi

    2016-04-01

    An investigation was conducted from summer 2012 to winter 2013 at 25 stations along the Tunisian coast near Kef Abbed at Marsa Dhouiba (north-east Mediterranean Sea) to analyse grain size, sediment mineralogy and currents. Particle-size analysis shows that sand deposits at shallow depths are characterised by S-shaped curves, indicating a degree of agitation and possible transport by rip currents near the bottom. At greater depths (between 10 and 30 m), the bottom is covered by coarse sand and gravel. A current was observed transporting sediment eastward along the coast; another seaward current was also noted. Generated by wind, swell and especially waves from west to north-west, the two currents transport clay and silt-sized sediment seaward. An Acoustic Doppler Current Profiler showed Marsa Dhouiba's coastal current to follow a direction 175° East, with its main axis running north/north-west parallel to the coast and its minor axis also running north/north-west. Analysis of current components indicates that the velocities u and v are oriented north to south. Sediment evolution in shallow waters is dependent on detrital inputs from streams and winds. The coarse fraction of surface sediments in Marsa Dhouiba presents 87% of total sediments and is located at depths of 10-30 m. Sediment dynamics in the Marsa Dhouiba region are closely related to the west/north-west swell.

  18. Genome-Wide Divergence in the West-African Malaria Vector Anopheles melas.

    PubMed

    Deitz, Kevin C; Athrey, Giridhar A; Jawara, Musa; Overgaard, Hans J; Matias, Abrahan; Slotman, Michel A

    2016-01-01

    Anopheles melas is a member of the recently diverged An. gambiae species complex, a model for speciation studies, and is a locally important malaria vector along the West-African coast where it breeds in brackish water. A recent population genetic study of An. melas revealed species-level genetic differentiation between three population clusters. An. melas West extends from The Gambia to the village of Tiko, Cameroon. The other mainland cluster, An. melas South, extends from the southern Cameroonian village of Ipono to Angola. Bioko Island, Equatorial Guinea An. melas populations are genetically isolated from mainland populations. To examine how genetic differentiation between these An. melas forms is distributed across their genomes, we conducted a genome-wide analysis of genetic differentiation and selection using whole genome sequencing data of pooled individuals (Pool-seq) from a representative population of each cluster. The An. melas forms exhibit high levels of genetic differentiation throughout their genomes, including the presence of numerous fixed differences between clusters. Although the level of divergence between the clusters is on a par with that of other species within the An. gambiae complex, patterns of genome-wide divergence and diversity do not provide evidence for the presence of pre- and/or postmating isolating mechanisms in the form of speciation islands. These results are consistent with an allopatric divergence process with little or no introgression. PMID:27466271

  19. Genome-Wide Divergence in the West-African Malaria Vector Anopheles melas

    PubMed Central

    Deitz, Kevin C.; Athrey, Giridhar A.; Jawara, Musa; Overgaard, Hans J.; Matias, Abrahan; Slotman, Michel A.

    2016-01-01

    Anopheles melas is a member of the recently diverged An. gambiae species complex, a model for speciation studies, and is a locally important malaria vector along the West-African coast where it breeds in brackish water. A recent population genetic study of An. melas revealed species-level genetic differentiation between three population clusters. An. melas West extends from The Gambia to the village of Tiko, Cameroon. The other mainland cluster, An. melas South, extends from the southern Cameroonian village of Ipono to Angola. Bioko Island, Equatorial Guinea An. melas populations are genetically isolated from mainland populations. To examine how genetic differentiation between these An. melas forms is distributed across their genomes, we conducted a genome-wide analysis of genetic differentiation and selection using whole genome sequencing data of pooled individuals (Pool-seq) from a representative population of each cluster. The An. melas forms exhibit high levels of genetic differentiation throughout their genomes, including the presence of numerous fixed differences between clusters. Although the level of divergence between the clusters is on a par with that of other species within the An. gambiae complex, patterns of genome-wide divergence and diversity do not provide evidence for the presence of pre- and/or postmating isolating mechanisms in the form of speciation islands. These results are consistent with an allopatric divergence process with little or no introgression. PMID:27466271

  20. 50 CFR 600.525 - Applicability of subpart F to Canadian Albacore Fishing Vessels off the West Coast.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Albacore Fishing Vessels off the West Coast. 600.525 Section 600.525 Wildlife and Fisheries FISHERY...-STEVENS ACT PROVISIONS Foreign Fishing § 600.525 Applicability of subpart F to Canadian Albacore Fishing Vessels off the West Coast. Fishing by vessels of Canada under the 1981 Treaty Between the Government...

  1. 78 FR 45288 - Frank Sherman, Evergreen Trails, Inc., Cabana Coaches, LLC, TMS West Coast, Inc. and FSCS...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-26

    ... Surface Transportation Board Frank Sherman, Evergreen Trails, Inc., Cabana Coaches, LLC, TMS West Coast... Trails, Inc. (Evergreen), Cabana Coaches, LLC (Cabana), TMS West Coast, Inc. (TMS), and FSCS Corporation... shareholder of noncarrier holding companies FSCS and TMS. Cabana is owned directly by FSCS and Evergreen...

  2. 50 CFR 600.525 - Applicability of subpart F to Canadian Albacore Fishing Vessels off the West Coast.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Albacore Fishing Vessels off the West Coast. 600.525 Section 600.525 Wildlife and Fisheries FISHERY...-STEVENS ACT PROVISIONS Foreign Fishing § 600.525 Applicability of subpart F to Canadian Albacore Fishing Vessels off the West Coast. Fishing by vessels of Canada under the 1981 Treaty Between the Government...

  3. Industrial Relations and Firm Behavior: Informal Labor Practices in the West Coast Longshore Industry.

    ERIC Educational Resources Information Center

    Finlay, William

    1987-01-01

    Considers industrial relations policies and practices of stevedore firms in the West Coast longshore industry in terms of the social worker, worker-resource, and institutional theories. Subsidiary firms were more lenient in contract interpretation and more competitive in recruitment, supporting the worker-resource theory. Includes 2 tables and 33…

  4. 78 FR 54547 - Fisheries Off West Coast States; Highly Migratory Fisheries; California Drift Gillnet Fishery...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-04

    ... emergency rules (62 FR 44421; August 21, 1997) specify the following three criteria that define what an...; Issuance of Permit; Fisheries Off West Coast States; Highly Migratory Fisheries; California Drift Gillnet Fishery; Sperm Whale Interaction Restriction; Final Rule and Notice #0;#0;Federal Register / Vol. 78 ,...

  5. 77 FR 50952 - Fisheries Off West Coast States; Coastal Pelagic Species Fisheries; Closure

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-23

    ... National Oceanic and Atmospheric Administration 50 CFR Part 660 RIN 0648-XC166 Fisheries Off West Coast States; Coastal Pelagic Species Fisheries; Closure AGENCY: National Marine Fisheries Service (NMFS... live bait fishery or incidental to other fisheries; the incidental harvest of Pacific sardine...

  6. 75 FR 42610 - Fisheries Off West Coast States; Coastal Pelagic Species Fisheries; Closure

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-22

    ... National Oceanic and Atmospheric Administration 50 CFR Part 660 RIN 0648-XX54 Fisheries Off West Coast States; Coastal Pelagic Species Fisheries; Closure AGENCY: National Marine Fisheries Service (NMFS... live bait fishery or incidental to other fisheries; the incidental harvest of Pacific sardine...

  7. 76 FR 58720 - Fisheries Off West Coast States; Coastal Pelagic Species Fisheries; Closure

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-22

    ... National Oceanic and Atmospheric Administration 50 CFR Part 660 RIN 0648-XA709 Fisheries Off West Coast States; Coastal Pelagic Species Fisheries; Closure AGENCY: National Marine Fisheries Service (NMFS... bait fishery or incidental to other fisheries; the incidental harvest of Pacific sardine is limited...

  8. 75 FR 59156 - Fisheries Off West Coast States; Coastal Pelagic Species Fisheries; Closure

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-27

    ... National Oceanic and Atmospheric Administration 50 CFR Part 660 RIN 0648-XY79 Fisheries Off West Coast States; Coastal Pelagic Species Fisheries; Closure AGENCY: National Marine Fisheries Service (NMFS... bait fishery or incidental to other fisheries; the incidental harvest of Pacific sardine is limited...

  9. 76 FR 40836 - Fisheries Off West Coast States; Coastal Pelagic Species Fisheries; Closure

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-12

    ... National Oceanic and Atmospheric Administration 50 CFR Part 660 RIN 0648-XA554 Fisheries Off West Coast States; Coastal Pelagic Species Fisheries; Closure AGENCY: National Marine Fisheries Service (NMFS... live bait fishery or incidental to other fisheries; the incidental harvest of Pacific sardine...

  10. A PROBABILISTIC SURVEY OF FISH TISSUE CONTAMINATION FROM THE CONTINENTAL SHELF OF THE US WEST COAST

    EPA Science Inventory

    A probabilistic survey of environmental condition of the continental shelf of the US West Coast was conducted in 2003 by the US EPA National Coastal Assessment (NCA), with collaboration by the NOAA National Marine Fisheries Service. Metals and organic contaminants were analyzed ...

  11. New Cultural Economies of Marginality: Revisiting the West Coast, South Island, New Zealand

    ERIC Educational Resources Information Center

    Conradson, David; Pawson, Eric

    2009-01-01

    Marginal regions have been the subject of political concern and remedial action in western states for several decades now. The West Coast of the South Island of New Zealand is an interesting case study in this regard, for recent economic growth has confounded earlier expectations of post-restructuring decline, while also contradicting several of…

  12. 76 FR 65155 - Fisheries Off West Coast States; Highly Migratory Species Fisheries; Swordfish Retention Limits

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-20

    ....S. West Coast-based deep-set tuna longline (DSLL) fishery. The DSLL fishery is managed under the... accompanying appendices are available on the Pacific Fishery Management Council's Web site at http://www... February 4, 2004 (69 FR 18444). The majority of HMS FMP implementing regulations became effective on...

  13. New record of Norileca indica from the west coast of India.

    PubMed

    Rameshkumar, Ganapathy; Ramesh, Mathan; Ravichandran, Samuthirapandian; Trilles, Jean-Paul; Subbiah, Shunmugam

    2015-12-01

    Two hundred and twenty samples of Rastrelliger kanagurta from the Cochin Fisheries Harbour were collected during the month of August 2013. Forty-one specimens (32 females and 9 males) were parasitized by the cymothoid isopod Norileca indica. N. indica is recorded for the first time from the west coast of India.

  14. 75 FR 11068 - Fisheries Off West Coast States; Coastal Pelagic Species Fisheries; Annual Specifications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-10

    ... conserve and manage Pacific sardine off the West Coast. DATES: Effective March 10, 2010 through December 31..., 1999 (64 FR 69888), divides management unit species into two categories: actively managed and monitored... the Council's Scientific and Statistical Committee (SSC). At that time, the biomass, the overall...

  15. Monarch butterflies cross the Appalachians from the west to recolonize the east coast of North America.

    PubMed

    Miller, Nathan G; Wassenaar, Leonard I; Hobson, Keith A; Norris, D Ryan

    2011-02-23

    Each spring, millions of monarch butterflies (Danaus plexippus) migrate from overwintering sites in Mexico to recolonize eastern North America. However, few monarchs are found along the east coast of the USA until mid-summer. Brower (Brower, L. P. 1996 J. Exp. Biol. 199, 93-103.) proposed that east coast recolonization is accomplished by individuals migrating from the west over the Appalachians, but to date no evidence exists to support this hypothesis. We used hydrogen (δD) and carbon (δ(13)C) stable isotope measurements to estimate natal origins of 90 monarchs sampled from 17 sites along the eastern United States coast. We found the majority of monarchs (88%) originated in the mid-west and Great Lakes regions, providing, to our knowledge, the first direct evidence that second generation monarchs born in June complete a (trans-) longitudinal migration across the Appalachian mountains. The remaining individuals (12%) originated from parents that migrated directly from the Gulf coast during early spring. Our results provide evidence of a west to east longitudinal migration and provide additional rationale for conserving east coast populations by identifying breeding sources. PMID:20630891

  16. Monarch butterflies cross the Appalachians from the west to recolonize the east coast of North America

    PubMed Central

    Miller, Nathan G.; Wassenaar, Leonard I.; Hobson, Keith A.; Norris, D. Ryan

    2011-01-01

    Each spring, millions of monarch butterflies (Danaus plexippus) migrate from overwintering sites in Mexico to recolonize eastern North America. However, few monarchs are found along the east coast of the USA until mid-summer. Brower (Brower, L. P. 1996 J. Exp. Biol. 199, 93–103.) proposed that east coast recolonization is accomplished by individuals migrating from the west over the Appalachians, but to date no evidence exists to support this hypothesis. We used hydrogen (δD) and carbon (δ13C) stable isotope measurements to estimate natal origins of 90 monarchs sampled from 17 sites along the eastern United States coast. We found the majority of monarchs (88%) originated in the mid-west and Great Lakes regions, providing, to our knowledge, the first direct evidence that second generation monarchs born in June complete a (trans-) longitudinal migration across the Appalachian mountains. The remaining individuals (12%) originated from parents that migrated directly from the Gulf coast during early spring. Our results provide evidence of a west to east longitudinal migration and provide additional rationale for conserving east coast populations by identifying breeding sources. PMID:20630891

  17. 75 FR 38030 - Magnuson-Stevens Act Provisions; Fisheries Off West Coast States; Pacific Coast Groundfish...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-01

    ....gpoaccess.gov/fr/index.html . Background information and documents are available at the Pacific Fishery... for the Pacific Coast groundfish fishery (73 FR 80516). A final rule was published on March 6, 2009 (74 FR 9874), which codified the specifications and management measures in the CFR (50 CFR part...

  18. 75 FR 33196 - Fisheries off West Coast States; Pacific Coast Groundfish Fishery; Suspension of the Primary...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-11

    ... States; Pacific Coast Groundfish Fishery; Suspension of the Primary Pacific Whiting Season for the Shore... announces the suspension of the Pacific whiting (whiting) fishery primary season for the shore-based sector... reinstated until 0001 hours June 15, 2010, at which time the primary season for the shore-based sector...

  19. 76 FR 67092 - Magnuson-Stevens Act Provisions; Fisheries Off West Coast States; Pacific Coast Groundfish...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-31

    ... site at http://www.gpoaccess.gov/fr/index.html . Background information and documents are available at... measures for the Pacific Coast groundfish fishery (75 FR 67810). The final rule to implement the 2011-2012... May 11, 2011 (76 FR 27508). This final rule was subsequently amended by inseason actions on June...

  20. 76 FR 38313 - Magnuson-Stevens Act Provisions; Fisheries Off West Coast States; Pacific Coast Groundfish...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-30

    ... the Office of the Federal Register's Web site at http://www.gpoaccess.gov/fr/index.html . Background... specifications and management measures for the Pacific Coast groundfish fishery (75 FR 67810). The final rule to... Fishery was published on May 11, 2011 (76 FR 27508). These specifications and management measures...

  1. 75 FR 8820 - Magnuson-Stevens Act Provisions; Fisheries Off West Coast States; Pacific Coast Groundfish...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-26

    ... Federal Register's Web site at http://www.gpoaccess.gov/fr/index.html . Background information and... December 31, 2008, (73 FR 80516). The final rule to implement the 2009-2010 specifications and management measures for the Pacific Coast Groundfish Fishery was published on March 6, 2009 (74 FR 9874). This...

  2. 75 FR 51684 - Magnuson-Stevens Act Provisions; Fisheries Off West Coast States; Pacific Coast Groundfish...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-23

    ....gpoaccess.gov/fr/index.html . Background information and documents are available at the Pacific Fishery... for the Pacific Coast groundfish fishery (73 FR 80516). The final rule to implement the 2009-2010... (74 FR 9874). This final rule was subsequently amended by inseason actions on April 27, 2009 (74...

  3. 75 FR 75417 - Magnuson-Stevens Act Provisions; Fisheries Off West Coast States; Pacific Coast Groundfish...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-03

    ... groundfish fishery (73 FR 80516). The final rule to implement the 2009-2010 specifications and management measures for the Pacific Coast Groundfish Fishery was published on March 6, 2009 (74 FR 9874). This final... Internet at the Office of the Federal Register's Web site at...

  4. 77 FR 29955 - Fisheries Off West Coast States; Pacific Coast Groundfish Fishery Management Plan; Trawl...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-21

    ... critical habitat: Sei whales (Balaenoptera borealis); North Pacific Right whales (Eubalaena japonica); Blue... rationalization program for the Pacific coast groundfish fishery's trawl fleet (see 75 FR 78344; Dec. 15, 2010... ANPR on April 4, 2012 (77 FR 20337) that, among other things, announced the court's order, the...

  5. 78 FR 72 - Fisheries Off West Coast States; Pacific Coast Groundfish Fishery Management Plan; Trawl...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-02

    ... coast groundfish fishery's trawl fleet (see 75 FR 78344; Dec. 15, 2010). The program was adopted in 2010... follow. NMFS published the ANPR on April 4, 2012 (77 FR 20337), which, among other things, announced the... 21, 2012 (77 FR 29955), with the final rule published on August 1, 2012 (77 FR 45508). RAW 1...

  6. 76 FR 34910 - Magnuson-Stevens Act Provisions; Fisheries Off West Coast States; Pacific Coast Groundfish...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-15

    ... Distinct Population Segment (DPS) of green sturgeon was listed as threatened under the ESA (71 FR 17757... the ESA (75 FR 13012). NMFS has reinitiated consultation on the fishery, including impacts on green... management measures for that fishery off the coasts of Washington, Oregon, and California (76 FR 27508)....

  7. 76 FR 11381 - Magnuson-Stevens Act Provisions; Fisheries Off West Coast States; Pacific Coast Groundfish...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-02

    ... http://www.gpoaccess.gov/fr/index.html . Background information and documents are available at the... management measures for the Pacific Coast groundfish fishery (73 FR 80516). The final rule to implement the... on March 6, 2009 (74 FR 9874). The final rule was subsequently amended by inseason actions on...

  8. 75 FR 41383 - Magnuson-Stevens Act Provisions; Fisheries off West Coast States; Pacific Coast Groundfish...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-16

    ....gpoaccess.gov/fr/index.html . Background information and documents are available at the Pacific Fishery... for the Pacific Coast groundfish fishery (73 FR 80516). The final rule to implement the 2009-2010... (74 FR 9874). This final rule was subsequently amended by inseason actions on April 27, 2009 (74...

  9. 76 FR 28897 - Magnuson-Stevens Act Provisions; Fisheries Off West Coast States; Pacific Coast Groundfish...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-19

    ... via the Internet at the Office of the Federal Register's Web site at http://www.gpoaccess.gov/fr/index... for the Pacific Coast groundfish fishery (75 FR 67810). A final rule was published on May 11, 2011 (76 FR 27508) that responded to public comments and codified the specifications and management...

  10. 75 FR 39178 - Magnuson-Stevens Act Provisions; Fisheries Off West Coast States; Pacific Coast Groundfish...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-08

    ....gpoaccess.gov/fr/index.html . Background information and documents are available at the Pacific Fishery... for the Pacific Coast groundfish fishery (73 FR 80516), including, among other species, darkblotched rockfish, cowcod, and yelloweye rockfish. A final rule was published on March 6, 2009 (74 FR 9874),...

  11. 76 FR 79122 - Magnuson-Stevens Act Provisions; Fisheries Off West Coast States; Pacific Coast Groundfish...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-21

    ... management measures for most species of the Pacific Coast groundfish fishery (75 FR 67810). The final rule to... Groundfish Fishery was published on May 11, 2011 (76 FR 27508). This final rule was subsequently amended by inseason actions on June 30, 2011 (76 FR 38313) and October 31, 2011 (76 FR 67092). Additional changes...

  12. 75 FR 61102 - Magnuson-Stevens Act Provisions; Fisheries Off West Coast States; Pacific Coast Groundfish...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-04

    ... specifications and management measures for the Pacific Coast groundfish fishery (73 FR 80516). The final rule to... Register's Web site at http://www.gpoaccess.gov/fr/index.html . Background information and documents are... published on March 6, 2009 (74 FR 9874). This final rule was subsequently amended by inseason actions...

  13. 75 FR 23620 - Magnuson-Stevens Act Provisions; Fisheries Off West Coast States; Pacific Coast Groundfish...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-04

    ... Coast groundfish fishery (73 FR 80516). A final rule was published on March 6, 2009 (74 FR 9874), which... via the Internet at the Office of the Federal Register's Web site at http://www.gpoaccess.gov/fr/index... allocation and management of the 2010 tribal Pacific whiting fishery (75 FR 11829). The comment period...

  14. 78 FR 43125 - Fisheries off West Coast States; Pacific Coast Groundfish Fishery Management Plan; Commercial...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-19

    ... the Pacific coast groundfish fishery's trawl fleet (see 75 FR 78344; Dec. 15, 2010). The program was... participants in the Shorebased IFQ sector was approved under the original provisions of the program (see 75 FR... species with the exception of widow rockfish (see 77 FR 45508 and 78 FR 18879). By implementing...

  15. 76 FR 42588 - Fisheries Off West Coast States; Pacific Coast Groundfish Fishery Management Plan; Amendments 20...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-19

    ... INFORMATION: On December 30, 2010, NMFS published a rule (75 FR 82296) that, among other actions, revised the... measures (May 11, 2011, 76 FR 27508), and are not related to the measures at issue in this notice. The... States; Pacific Coast Groundfish Fishery Management Plan; Amendments 20 and 21; Trawl...

  16. 76 FR 50449 - Fisheries off West Coast States; Pacific Coast Groundfish Fishery Management Plan; Trawl...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-15

    ... Improvement and Enhancement; Amendment 21-1 AGENCY: National Marine Fisheries Service (NMFS), National Oceanic... (Council) has submitted Amendment 21-1 to the Pacific Coast Groundfish Fishery Management Plan (FMP) for review by the Secretary of Commerce (Secretary). Amendment 21-1 would further revise the FMP to...

  17. Critical Postcolonial Dance Pedagogy: The Relevance of West African Dance Education in the United States

    ERIC Educational Resources Information Center

    Cruz Banks, Ojeya

    2010-01-01

    This dance ethnography examines work conducted by the Dambe Project--a nonprofit organization that specializes in African performing arts education and mentorship. The study focuses on the implications of the organization's dance pedagogy in light of its postcolonial context and the importance of West African dance education in the United States.…

  18. Cold War and Colonial Conflicts in British West African Adult Education, 1947-1953.

    ERIC Educational Resources Information Center

    Fieldhouse, Roger

    1984-01-01

    Adult education was introduced by the British into West Africa after World War II. However, the Oxford intellectuals put in charge of the adult education program offered an African-centered education that frequently offered more support to the progressive views of the African independence movements than to the colonialists' conservative policies.…

  19. 75 FR 67032 - Fisheries Off West Coast States; Pacific Coast Groundfish Fishery Management Plan; Amendments 20...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-01

    ... INFORMATION: Background On October 1, 2010, NMFS published a final rule (75 FR 32994, 100212086-0354-04) that..., 2010, initial issuance final rule (75 FR 32994). The correction to the trip limit tables in the limited... National Oceanic and Atmospheric Administration 50 CFR Part 660 RIN 0648-AY68 Fisheries Off West...

  20. A cyclogenesis index for tropical Atlantic off the African coasts

    NASA Astrophysics Data System (ADS)

    Sall, Saïdou Moustapha; Sauvageot, Henri; Gaye, Amadou Thierno; Viltard, Alain; de Felice, Pierre

    2006-02-01

    The westward moving Soudano-Sahelian mesoscale convective systems (MCS) frequently reach and cross the Atlantic Coast. At the end of their continental route, most MCS weaken and vanish over the ocean, near the coast, while others strengthen. The latter play an important part in the genesis of some Atlantic tropical cyclones. In the present paper, following the work of Gray (1977, 1979) [Gray, W.M., 1977. Tropical cyclone genesis in the western North Pacific. J. Meteorol. Soc. Jpn. 55, 465-482; Gray, W.M., 1979. Hurricanes: their formation, structure and likely role in the tropical circulation. Meteorology over the Tropical Oceans, D.B. Shaw, (Ed.), Roy. Meteorol. Soc., 155-218] and Gray et al. (1994, 1999) [Gray, W.M., Landsea, C.W., Mielke Jr., P.W., Berry, K.J., 1994. Predicting Atlantic seasonal tropical cyclone activity by 1 June. Weather Forecast. 9, 103-115; Gray, W.M., Landsea, C.W., Mielke Jr., P.W., Berry, K.J., 1999. Forecast of Atlantic seasonal hurricane activity for 1999. Dept. of Atmos. Sci. Report, Colo. State Univ., Ft. Collins, CO, released on 4 June, 1999], an index liable to be associated with the coast-crossing MCS cyclonic evolution is built. The data used in this work are observations by the Dakar-Yoff radar, reanalyses of NCEP/NCAR (National Centers for Environmental Prediction/National Center for Atmospheric Research), outgoing long wave radiation at the top of the atmosphere, and the resources of the National Hurricane Center data base. Several terms describing the variation of individual meteorological parameters are first analysed and then combined into an index of cyclogenesis or ICY. Combination of vertical vorticity at 925 hPa and potential vorticity at 700 hPa is notably found to be a good factor to discriminate between strengthening and weakening MCS over the near Atlantic. A good correlation between the ICY maximum and the beginning of the MCS cyclogenesis is observed. This index enables discrimination of the simultaneous presence

  1. Remote sensing of wetland conditions in West Coast salt marshes

    NASA Astrophysics Data System (ADS)

    Ustin, Susan L.; Lay, Mui C.; Li, Lin

    2004-11-01

    The objective of the PEEIR (Pacific Estuarine Ecosystem Indicator Research Consortium) program is to develop new indicators for assessing wetland health or condition. As part of PEEIR program we are investigating the use of imaging spectrometry to map and characterize marsh vegetation of several estuarine systems in California. We obtained airborne Advanced Visible Infrared Imaging Spectrometer (AVIRIS) data, an instrument which measures a detailed reflectance spectrum (400-2500nm) for each pixel, over paired tidal marshes, having either a history of exposure to pollution or no known exposure. AVIRIS image data was analyzed based on comparison to field measurements and reflectance changes measured in hydroponic experiments. We report leaf and canopy reflectance measurements of several common plant species of Pacific coast salt marshes exposed to different concentrations of heavy metals (Cd, V) and crude oil contaminants. Species exhibited differential sensitivities to specific contaminants, however in general, Salicornia virginica, the most salt tolerant species and the dominant species in these wetlands (70-90% cover) was most sensitive to metal and petroleum contaminants. Field measurements of canopy reflectance, biomass and vegetation structure were acquired across GPS-located transects at each field site. The AVIRIS data were calibrated to surface reflectance using the FLAASH radiative transfer code and geometrically registered to coordinates using the 1m USGS digital orthophoto quads. AVIRIS results show spatial patterns of plant stress indicators (e.g., reduced chlorophyll and water contents) are consistent with known patterns of contamination in these tidal wetlands.

  2. Litter in submarine canyons off the west coast of Portugal

    NASA Astrophysics Data System (ADS)

    Mordecai, Gideon; Tyler, Paul A.; Masson, Douglas G.; Huvenne, Veerle A. I.

    2011-12-01

    Marine litter is of global concern and is present in all the world's oceans, including deep benthic habitats where the extent of the problem is still largely unknown. Litter abundance and composition were investigated using video footage and still images from 16 Remotely Operated Vehicle (ROV) dives in Lisbon, Setúbal, Cascais and Nazaré Canyons located west of Portugal. Litter was most abundant at sites closest to the coastline and population centres, suggesting the majority of the litter was land sourced. Plastic was the dominant type of debris, followed by fishing gear. Standardised mean abundance was 1100 litter items km -2, but was as high as 6600 litter items km -2 in canyons close to Lisbon. Although all anthropogenic material may be harmful to biota, debris was also used as a habitat by some macro-invertebrates. Litter composition and abundance observed in the canyons of the Portuguese margin were comparable to those seen in other deep sea areas around the world. Accumulation of litter in the deep sea is a consequence of human activities both on land and at sea. This needs to be taken into account in future policy decisions regarding marine pollution.

  3. Evaluation of West African Monsoon Processes and Feedbacks: Second West African Monsoon Modeling and Evaluation Project Experiment (WAMME II)

    NASA Astrophysics Data System (ADS)

    Xue, Y.; Lau, W. K.; Boone, A. A.; Seidou Sanda, I.; Thiaw, W. M.; Druyan, L.; Team, W.

    2013-12-01

    Despite recent progress in understanding of the West African monsoon (WAM), there are still many unanswered questions regarding to the impact of external forcings: oceans, land, and aerosols, on WAM variability, especially their roles in the Sahel drought. The West African Monsoon Modeling and Evaluation (WAMME) is a project comprised of both general circulation models (GCMs) and regional climate models (RCMs) with the objective to collectively provide best estimation of the relative importance of all those external forcing on WAM on seasonal to multi-decadal time scales. WAMME research activities are closely coordinated with those of AMMA, involving many African institutions. Observational evidence has shown strong decadal climate variabilities in the Sahel from the 1950s to the 2000s, not only in precipitation, but also in SST, vegetation cover, land use and land cover changes (LULCC), and aerosols. In WAMME-2, multi-model intercomparison experiments are designed to test how seasonal and decadal variabilities of WAM precipitation are associated with these forcings, and assess their relative contributions in producing/amplifying the WAM seasonal and decadal climate variability. The sensitivity of the WAM variability to those external forcings is also examined. The WAMME-2 strategy is to apply observational data-based anomaly forcing of SST, land surface and aerosols, i.e., "idealized but realistic" forcing, in GCM and RCM simulations with the specific purpose of estimating the relative impacts of each forcing and feedback mechanisms. In the SST experiment, in addition to the global SST effect, each ocean's role is also evaluated. The preliminary results from most GCMs consistently indicate that SST has a maximum impact on the WAM decadal variability compared with other forcings, and that the effect of the Pacific Ocean is most dominant. The models, however, differ in producing other oceans' contribution. Moreover, the models with specified maximum SST forcing are

  4. Mothers and Sons: Androgynous Relationships in African-West Indian and African-American Novels of Youth.

    ERIC Educational Resources Information Center

    LeSeur, Geta

    1992-01-01

    Four African-American and West Indian novels of childhood illustrate relationships and bonding between mothers and sons: (1) "Go Tell It on the Mountain" (James Baldwin); (2) "Not without Laughter" (Langston Hughes); (3) "Amongst Thistles and Thorns" (Austin Clarke); and (4) "In the Castle of My Skin" (George Lanning). (SLD)

  5. Application of Nimbus-6 microwave data to problems in precipitation prediction for the Pacific west coast

    NASA Technical Reports Server (NTRS)

    Viezee, W.; Shigeishi, H.; Chang, A. T. C.

    1979-01-01

    The preliminary results of a research study that emphasizes the analysis and interpretation of data related to total precipitable water and nonprecipitating cloud liquid water obtained from NIMBUS-6 SCAMS are reported. Sixteen cyclonic storm situations in the northeastern Pacific Ocean that resulted in significant rainfall along the west coast of the United States during the winter season October 1975 through February 1976 are analyzed in terms of their distributions and amounts of total water vapor and liquid water, as obtained from SCAMS data. The water-substance analyses for each storm case are related to the distribution and amount of coastal precipitation observed during the subsequent time period when the storm system crosses the coastline. Concomitant precipitation predictions from the LFM are also incorporated. Techniques by which satellite microwave data over the ocean can be used to improve precipitation prediction for the Pacific West Coast are emphasized.

  6. Analysis of Hanford-based Options for Sustainable DOE Facilities on the West Coast

    SciTech Connect

    Warwick, William M.

    2012-06-30

    Large-scale conventional energy projects result in lower costs of energy (COE). This is true for most renewable energy projects as well. The Office of Science is interested in its facilities meeting the renewable energy mandates set by Congress and the Administration. Those facilities on the west coast include a cluster in the Bay Area of California and at Hanford in central Washington State. Land constraints at the California facilities do not permit large scale projects. The Hanford Reservation has land and solar insolation available for a large scale solar project as well as access to a regional transmission system that can provide power to facilities in California. The premise of this study is that a large-scale solar project at Hanford may be able to provide renewable energy sufficient to meet the needs of select Office of Science facilities on the west coast at a COE that is competitive with costs in California despite the lower solar insolation values at Hanford. The study concludes that although the cost of solar projects continues to decline, estimated costs for a large-scale project at Hanford are still not competitive with avoided power costs for Office of Science facilities on the west coast. Further, although it is possible to transmit power from a solar project at Hanford to California facilities, the costs of doing so add additional costs. Consequently, development of a large- scale solar project at Hanford to meet the renewable goals of Office of Science facilities on the west coast is currently uneconomic. This may change as solar costs decrease and California-based facilities face increasing costs for conventional and renewable energy produced in the state. PNNL should monitor those cost trends.

  7. Atmospheric rivers as drought busters on the U.S. west coast

    USGS Publications Warehouse

    Dettinger, Michael D.

    2013-01-01

    Atmospheric rivers (ARs) have, in recent years, been recognized as the cause of the large majority of major floods in rivers all along the U.S. West Coast and as the source of 30%–50% of all precipitation in the same region. The present study surveys the frequency with which ARs have played a critical role as a common cause of the end of droughts on the West Coast. This question was based on the observation that, in most cases, droughts end abruptly as a result of the arrival of an especially wet month or, more exactly, a few very large storms. This observation is documented using both Palmer Drought Severity Index and 6-month Standardized Precipitation Index measures of drought occurrence for climate divisions across the conterminous United States from 1895 to 2010. When the individual storm sequences that contributed most to the wet months that broke historical West Coast droughts from 1950 to 2010 were evaluated, 33%–74% of droughts were broken by the arrival of landfalling AR storms. In the Pacific Northwest, 60%–74% of all persistent drought endings have been brought about by the arrival of AR storms. In California, about 33%–40% of all persistent drought endings have been brought about by landfalling AR storms, with more localized low pressure systems responsible for many of the remaining drought breaks.

  8. Backtrack modeling to locate the origin of tar balls depositing along the west coast of India.

    PubMed

    Suneel, V; Ciappa, A; Vethamony, P

    2016-11-01

    Tar ball (TB) deposition along the West Coast of India (WCI) is a common phenomenon during the southwest monsoon season, particularly along the coast of Goa and Gujarat, and it is a major concern to the stake holders. Our earlier studies showed that the source oil for the TBs deposited on the Goa coast in August 2010 is the tanker wash, and the source for subsequent TBs deposited on the Gujarat coast during July 2012 and June 2013 and Goa coast in May 2013 is from Bombay High (BH) oil fields. In the present study, the TBs that were deposited during May 2013 and May 2014 on the Goa coast were backtracked through a trajectory model, primarily to simulate their pathways and identify the reason for the occurrence of TBs only in May, and eventually to identify the origin and the source. The backtracking results re-confirmed that the TBs deposited in 2010 were originated from the tanker routes and that of both 2013 and 2014 TBs from the BH oil fields. The climatology of wind and surface circulation showed that the TBs deposited on the Goa coast during May/June only are from the oil fields and those during August from the tanker route. The results of backtracking simulations showed that the residence time of the oil residues/TBs is approximately 22days for August 2010 TBs, ≈30days for May 2013 TBs and 65days for May 2014 TBs. The residence time (in water) of TBs that deposit (on the coast) in the month of May could be as much as 7months, and could be around one month if deposit in August, primarily because of winds and hydrodynamic conditions of the Arabian Sea. PMID:27328397

  9. Backtrack modeling to locate the origin of tar balls depositing along the west coast of India.

    PubMed

    Suneel, V; Ciappa, A; Vethamony, P

    2016-11-01

    Tar ball (TB) deposition along the West Coast of India (WCI) is a common phenomenon during the southwest monsoon season, particularly along the coast of Goa and Gujarat, and it is a major concern to the stake holders. Our earlier studies showed that the source oil for the TBs deposited on the Goa coast in August 2010 is the tanker wash, and the source for subsequent TBs deposited on the Gujarat coast during July 2012 and June 2013 and Goa coast in May 2013 is from Bombay High (BH) oil fields. In the present study, the TBs that were deposited during May 2013 and May 2014 on the Goa coast were backtracked through a trajectory model, primarily to simulate their pathways and identify the reason for the occurrence of TBs only in May, and eventually to identify the origin and the source. The backtracking results re-confirmed that the TBs deposited in 2010 were originated from the tanker routes and that of both 2013 and 2014 TBs from the BH oil fields. The climatology of wind and surface circulation showed that the TBs deposited on the Goa coast during May/June only are from the oil fields and those during August from the tanker route. The results of backtracking simulations showed that the residence time of the oil residues/TBs is approximately 22days for August 2010 TBs, ≈30days for May 2013 TBs and 65days for May 2014 TBs. The residence time (in water) of TBs that deposit (on the coast) in the month of May could be as much as 7months, and could be around one month if deposit in August, primarily because of winds and hydrodynamic conditions of the Arabian Sea.

  10. The West African monsoon: Contribution of the AMMA multidisciplinary programme to the study of a regional climate system.

    NASA Astrophysics Data System (ADS)

    Lebel, T.; Janicot, S.; Redelsperger, J. L.; Parker, D. J.; Thorncroft, C. D.

    2015-12-01

    The AMMA international project aims at improving our knowledge and understanding of the West African monsoon and its variability with an emphasis on daily-to-interannual timescales. AMMA is motivated by an interest in fundamental scientific issues and by the societal need for improved prediction of the WAM and its impacts on water resources, health and food security for West African nations. The West African monsoon (WAM) has a distinctive annual cycle in rainfall that remains a challenge to understand and predict. The location of peak rainfall, which resides in the Northern Hemisphere throughout the year, moves from the ocean to the land in boreal spring. Around the end of June there is a rapid shift in the location of peak rainfall between the coast and around 10°N where it remains until about the end of August. In September the peak rainfall returns equatorward at a relatively steady pace and is located over the ocean again by November. The fact that the peak rainfall migrates irregularly compared to the peak solar heating is due to the interactions that occur between the land, the atmosphere and the ocean. To gain a better understanding of this complex climate system, a large international research programme was launched in 2002, the biggest of its kind into environment and climate ever attempted in Africa. AMMA has involved a comprehensive field experiment bringing together ocean, land and atmospheric measurements, on timescales ranging from hourly and daily variability up to the changes in seasonal activity over a number of years. This presentation will focus on the description of the field programme and its accomplishments, and address some key questions that have been recently identified to form the core of AMMA-Phase 2.

  11. The West African monsoon: Contribution of the AMMA multidisciplinary programme to the study of a regional climate system.

    NASA Astrophysics Data System (ADS)

    Lebel, T.; Janicot, S.; Redelsperger, J. L.; Parker, D. J.; Thorncroft, C. D.

    2014-12-01

    The AMMA international project aims at improving our knowledge and understanding of the West African monsoon and its variability with an emphasis on daily-to-interannual timescales. AMMA is motivated by an interest in fundamental scientific issues and by the societal need for improved prediction of the WAM and its impacts on water resources, health and food security for West African nations. The West African monsoon (WAM) has a distinctive annual cycle in rainfall that remains a challenge to understand and predict. The location of peak rainfall, which resides in the Northern Hemisphere throughout the year, moves from the ocean to the land in boreal spring. Around the end of June there is a rapid shift in the location of peak rainfall between the coast and around 10°N where it remains until about the end of August. In September the peak rainfall returns equatorward at a relatively steady pace and is located over the ocean again by November. The fact that the peak rainfall migrates irregularly compared to the peak solar heating is due to the interactions that occur between the land, the atmosphere and the ocean. To gain a better understanding of this complex climate system, a large international research programme was launched in 2002, the biggest of its kind into environment and climate ever attempted in Africa. AMMA has involved a comprehensive field experiment bringing together ocean, land and atmospheric measurements, on timescales ranging from hourly and daily variability up to the changes in seasonal activity over a number of years. This presentation will focus on the description of the field programme and its accomplishments, and address some key questions that have been recently identified to form the core of AMMA-Phase 2.

  12. The 2010 Chilean Tsunami Off the West Coast of Canada and the Northwest Coast of the United States

    NASA Astrophysics Data System (ADS)

    Rabinovich, Alexander B.; Thomson, Richard E.; Fine, Isaac V.

    2013-09-01

    The major ( M w = 8.8) Chilean earthquake of 27 February 2010 generated a trans-oceanic tsunami that was observed throughout the Pacific Ocean. Waves associated with this event had features similar to those of the 1960 tsunami generated in the same region by the Great ( M w = 9.5) 1960 Chilean Earthquake. Both tsunamis were clearly observed on the coast of British Columbia. The 1960 tsunami was measured by 17 analog pen-and-paper tide gauges, while the 2010 tsunami was measured by 11 modern digital coastal tide gauges, four NEPTUNE-Canada bottom pressure recorders located offshore from southern Vancouver Island, and two nearby open-ocean DART stations. The 2010 records were augmented by data from seven NOAA tide gauges on the coast of Washington State. This study examines the principal characteristics of the waves from the 2010 event (height, period, duration, and arrival and travel times) and compares these properties for the west coast of Canada with corresponding properties of the 1960 tsunami. Results show that the 2010 waves were approximately 3.5 times smaller than the 1960 waves and reached the British Columbia coast 1 h earlier. The maximum 2010 wave heights were observed at Port Alberni (98.4 cm) and Winter Harbour (68.3 cm); the observed periods ranged from 12 min at Port Hardy to 110-120 min at Prince Rupert and Port Alberni and 150 min at Bamfield. The open-ocean records had maximum wave heights of 6-11 cm and typical periods of 7 and 15 min. Coastal and open-ocean tsunami records revealed persistent oscillations that "rang" for 3-4 days. Tsunami energy occupied a broad band of periods from 3 to 300 min. Estimation of the inverse celerity vectors from cross-correlation analysis of the deep-sea tsunami records shows that the tsunami waves underwent refraction as they approached the coast of Vancouver Island with the direction of the incoming waves changing from an initial direction of 340° True to a direction of 15° True for the second train of waves

  13. Recruitment dynamics of two ecosystem engineers could drive shellfish populations in U.S. west coast estuaries

    EPA Science Inventory

    Two species of burrowing shrimp, Neotrypaea californiensis and Upogebia pugettensis are important members of intertidal mudflat communities in US West coast estuaries. Both species act as ecosystem engineers and influence the presence of other structured habitats and suspension ...

  14. Effects of Parity on Blood Pressure among West African Dogon Women

    PubMed Central

    Taylor, Jacquelyn Y.; Sampson, Deborah A.; Anderson, Cindy M.; Caldwell, Dennis; Taylor, Andre D.

    2012-01-01

    Objective This study examined the effect of parity on blood pressure (BP) readings and BMI among rural West African Dogon women. Design Correlational research design. Setting Sangha, West Africa Participants 133 West African Dogon Women Methods Demographic survey including age, number of children, history of hypertension, and village affiliation. BP readings were taken in accordance with JNC-7 guidelines. BMI was calculated from height and weight. Results Women with BP readings diagnostic of hypertension were typically older (M = 55.72 years) than those who were normotensive (M = 42.40). However, BMI, on average, was within normal range for both groups (22.81 and 22.15, respectively). A statistically significant difference was found between number of children and systolic BP (SBP), P = .015, with those having 5 or more children with higher SBP than those with one to three children. A statistically significant difference, P = .001, was found between hypertension and normotensive diagnostic groups. Conclusions This study shows that increased parity of five or more children may contribute to West African Dogon women’s risk factors for hypertension in terms of increased SBP. Because BMI was within normal range for both groups of women, it was not shown to be an independent risk factor for hypertension in this sample. Further studies, with larger samples followed throughout their childbearing years (before, during, and after each pregnancy), are needed before more definitive conclusions can be made regarding the effects of parity on BMI and BP among rural West African Dogon women. PMID:22870582

  15. Population Structure of Clinical Pseudomonas aeruginosa from West and Central African Countries

    PubMed Central

    Cholley, Pascal; Ka, Roughyatou; Guyeux, Christophe; Thouverez, Michelle; Guessennd, Nathalie; Ghebremedhin, Beniam; Frank, Thierry; Bertrand, Xavier; Hocquet, Didier

    2014-01-01

    Background Pseudomonas aeruginosa (PA) has a non-clonal, epidemic population with a few widely distributed and frequently encountered sequence types (STs) called ‘high-risk clusters’. Clinical P. aeruginosa (clinPA) has been studied in all inhabited continents excepted in Africa, where a very few isolates have been analyzed. Here, we characterized a collection of clinPA isolates from four countries of West and Central Africa. Methodology 184 non-redundant isolates of clinPA from hospitals of Senegal, Ivory Coast, Nigeria, and Central African Republic were genotyped by MLST. We assessed their resistance level to antibiotics by agar diffusion and identified the extended-spectrum β-lactamases (ESBLs) and metallo-β-lactamases (MBLs) by sequencing. The population structure of the species was determined by a nucleotide-based analysis of the entire PA MLST database and further localized on the phylogenetic tree (i) the sequence types (STs) of the present collection, (ii) the STs by continents, (iii) ESBL- and MBL-producing STs from the MLST database. Principal Findings We found 80 distinct STs, of which 24 had no relationship with any known STs. ‘High-risk’ international clonal complexes (CC155, CC244, CC235) were frequently found in West and Central Africa. The five VIM-2-producing isolates belonged to CC233 and CC244. GES-1 and GES-9 enzymes were produced by one CC235 and one ST1469 isolate, respectively. We showed the spread of ‘high-risk’ international clonal complexes, often described as multidrug-resistant on other continents, with a fully susceptible phenotype. The MBL- and ESBL-producing STs were scattered throughout the phylogenetic tree and our data suggest a poor association between a continent and a specific phylogroup. Conclusions ESBL- and MBL-encoding genes are borne by both successful international clonal complexes and distinct local STs in clinPA of West and Central Africa. Furthermore, our data suggest that the spread of a ST could be

  16. Chlorinated pesticide residues in sediments from the Arabian Sea along the central west coast of India

    SciTech Connect

    Sarkar, A.; Gupta, R.S.

    1987-12-01

    The problem of environmental contamination by persistent chlorinated pesticides still evokes major concern due to the presence of their residues in the environment and in human tissues. In developing countries like India organochlorine insecticides, especially DDT are extensively being used in agriculture and vector control programs. Few data are available on their levels of concentration from the seas around India. Persistent pesticides residues can be expected to accumulate in marine sediments. However, very little data on this are available along the Indian coast. An attempt has been made in the present communication to identify and quantify some of the chlorinated pesticides residues in the marine sediments collected from different region along the central west coast of India. This is a part of our ongoing project to monitor and map pollutants within the exclusive economic zone of India.

  17. ShakeAlert—An earthquake early warning system for the United States west coast

    USGS Publications Warehouse

    Burkett, Erin R.; Given, Douglas D.; Jones, Lucile M.

    2014-08-29

    Earthquake early warning systems use earthquake science and the technology of monitoring systems to alert devices and people when shaking waves generated by an earthquake are expected to arrive at their location. The seconds to minutes of advance warning can allow people and systems to take actions to protect life and property from destructive shaking. The U.S. Geological Survey (USGS), in collaboration with several partners, has been working to develop an early warning system for the United States. ShakeAlert, a system currently under development, is designed to cover the West Coast States of California, Oregon, and Washington.

  18. Changes in erosional and depositional processes with time and management of Goa Coast, central west coast of India

    NASA Astrophysics Data System (ADS)

    Nayak, Ganapati; D'Souza, Joseph

    2010-05-01

    Coastal and estuarine environments, world over are facing immense impact due to both natural and anthropogenic processes. The natural processes include climatic changes, rise in sea level, cyclone, flood, tsunamis, coastal erosion, salinity ingress and siltation. Likewise, anthropogenic pressures include population expansion, ocean traffic, dredging, resource exploitation, pollution, unplanned urbanization and intensive industrialization. Due to these impacts the fragile coastal ecosystem and its entities, like sub ecosystems, resources, morphological units are undergoing unprecedented degradation, rendering these coastal regions vulnerable, impinging risk to human population, livestock, properties, as also, devastation of resourceful lands. This accelerates economic fatalities and irreversible obliteration to the ecosystems. Evidences on the global concern towards this issue have been well established. The countries world over, including India, pledged consensus towards the protection of the fragile coastal ecosystems through UNCED, Agenda-21. India, on 19th February 1991, has designated specified corridors along the landward side of the coastline as "Coastal Regulatory Zones" (CRZ), through appropriate policy and law. In context with the CRZ notification, scientific database at local and site-specific areas, developed. Synergy of ecosystems, landscape and resources with demographic, tourism data, vis-à-vis, economic corridors/sectors aided the paradigms and criterion for local and site specific prescriptions for Goa Coast. The Goa coast is a part of central west coast of India and is characterized by pocket beaches flanked by rocky cliffs, estuaries, bays, and at some places mangroves. Beaches in southern Goa are long and linear in nature with sand dunes. The Mandovi and Zuari estuarine system in Goa is the largest in this part of the coast. Mud flats, swampy marshes and wetlands are found mainly along estuaries and creeks. The beaches of Goa are stable beaches

  19. Shaping Futures and Feminisms: Qur'anic Schools in West African Francophone Fiction

    ERIC Educational Resources Information Center

    Edwin, Shirin

    2011-01-01

    This article examines the representation of female education in Qur'anic schools in a selection of West African francophone novels. I argue that in being the earliest form of education for most Muslim women and also a neglected topic of scholarly interest, the Qur'anic school shapes their feminisms in more significant ways than has been…

  20. Comparative Analyses of Physics Candidates Scores in West African and National Examinations Councils

    ERIC Educational Resources Information Center

    Utibe, Uduak James; Agah, John Joseph

    2015-01-01

    The study is a comparative analysis of physics candidates' scores in West African and National Examinations Councils. It also investigates influence of gender. Results of 480 candidates were randomly selected form three randomly selected Senior Science Colleges using the WASSCE and NECOSSCE computer printout sent to the schools, transformed using…

  1. Diamond provenance studies from 40Ar/ 39Ar dating of clinopyroxene inclusions: An example from the west coast of Namibia

    NASA Astrophysics Data System (ADS)

    Phillips, D.; Harris, J. W.

    2009-11-01

    The west coast of Namibia is host to substantive detrital diamond deposits located in onshore and offshore beach gravels, desert deflation deposits and lower Orange river terraces. The origin of the Namibian diamonds is controversial, with some studies favouring derivation from distal Cretaceous/Jurassic kimberlites on the Kaapvaal craton, and others arguing that most diamonds originated from proximal Dwyka glacial deposits (~ 300 Ma), which incorporated diamonds from older (≥ 500 Ma), pre-Karoo kimberlites. Previous studies have demonstrated that clinopyroxene inclusions extracted from their host diamonds give 40Ar/ 39Ar ages approaching the time of source kimberlite eruption. This behaviour is attributed to diffusion of argon to lattice defect sites and the diamond/inclusion interface region during mantle residence, with subsequent loss of the latter component on cleaving of the diamond to release the inclusion(s). In this study, we measured 40Ar/ 39Ar ages of extracted clinopyroxene inclusions from Namibian detrital diamonds, in order to determine potential kimberlite sources, craton erosion histories and palaeo-drainage evolution in southern Africa. 40Ar/ 39Ar step-heating data were obtained for eclogitic and peridotitic clinopyroxene inclusions from 50 Namibian diamonds. Low temperature steps produced older apparent ages than high temperature (fusion) steps, consistent with partial retention of pre-eruption argon in defect sites. With one exception, fusion steps yielded younger ages, ranging from 62 ± 30 Ma to 1441 ± 700 Ma. The majority (80%) of inclusions have fusion ages < 300 Ma, indicating that most Namibian detrital diamonds originated from post-Dwyka (< 300 Ma) kimberlites. Six inclusion aliquots (13%) produced ages unique to Cretaceous Group I kimberlites, confirming erosion of diamonds from these sources. The proportion of diamonds sourced from Group II kimberlites is uncertain, although forward modelling suggests roughly equal quantities from

  2. On the importance of Sri Lanka for sea-level variability along the west coast of India

    NASA Astrophysics Data System (ADS)

    Suresh, I.; Vialard, J.; Izumo, T.; Lengaigne, M.; Han, W.; McCreary, J. P., Jr.; Pillathu Moolayil, M.

    2015-12-01

    Earlier studies have illustrated the strong influence of remote forcing from the equator and the Bay of Bengal on the sea-level variability off the west coast of India, especially at the seasonal timescale. More recently, Suresh et al. [2013] demonstrated with a simple, linear, continuously-stratified (LCS) model that the equatorial zonal winds contribute to more than 60% of intraseasonal sea-level variability along the Indian west coast. In the present study, we quantify the contributions from various processes to the sea-level variability along the west coast of India at different timescales with the help of a LCS model through both idealized and realistic sensitivity experiments. We demonstrate that remote forcing dominates the sea-level variability along the west coast of India at intraseasonal to interannual timescales. Sri Lanka and the southern tip of India play an important role on Indian west coast sea-level variability at all timescales for two reasons: First, the geometry of the coast favors a strong alongshore wind-stress forcing of coastal Kelvin waves across timescales there. Second, Sri Lanka interacts with low-order meridional mode equatorial Rossby waves forced by equatorial winds or southern Bay of Bengal wind- stress curl. This interaction of coastal waveguide with equatorial waveguide creates a new pathway for the equatorial signals to arrive at the west coast of India, alternative to the "classical" coastal waveguide around the rim of the Bay of Bengal. Reference: Suresh, I., J. Vialard, M. Lengaigne, W. Han, J. McCreary, F. Durand, and P. M. Muraleedharan (2013), Origins of wind-driven intraseasonal sea level variations in the North Indian Ocean coastal waveguide, Geophys. Res. Lett., 40, 5740-5744, doi:10.1002/2013GL058312.

  3. Morphometric and molecular analysis of mackerel (Rastrelliger spp) from the west coast of Peninsular Malaysia.

    PubMed

    Darlina, M N; Masazurah, A R; Jayasankar, P; Jamsari, A F J; Siti, A M N

    2011-01-01

    Mackerel (Scombridae; Rastrelliger) are small commercially important pelagic fish found in tropical regions. They serve as a cheap source of animal protein and are commonly used as live bait. By using a truss morphometrics protocol and RAPD analysis, we examined morphological and genetic variation among 77 individual mackerel that were caught using long lines and gillnets at 11 locations along the west coast of Peninsular Malaysia. Nineteen morphometric traits were evaluated and genetic information was estimated using five 10-base RAPD random primers. Total DNA was extracted from muscle tissue. Morphometric discriminant function analysis revealed that two morphologically distinct groups of Rastrelliger kanagurta and a single group of R. brachysoma can be found along the west coast of Peninsular Malaysia. We also found that the head-related characters and those from the anterior part of the body of Rastrelliger spp significantly contribute to stock assessment of this population. RAPD analysis showed a trend similar to that of the morphometric analysis, suggesting a genetic component to the observed phenotypic differentiation. These data will be useful for developing conservation strategies for these species. PMID:21968625

  4. The ecology of the seagrass meadows of the west coast of Florida: A community profile

    SciTech Connect

    Zieman, J.C.; Zieman, R.T. . Dept. of Environmental Sciences)

    1989-09-01

    This report summarizes information on the ecology of seagrass meadows on the west coast of Florida, from south of Tampa Bay to Pensacola. This area contains more than 3500 ha of seagrass beds, dominated by three species, Thalasia testudinum (turtle grass), Syringodium filiforme (manatee grass), and Halodule wrightii (shoal grass). Beds occur both on the shallow, zero-energy Continental Shelf and in inshore bays and estuaries. Species ecology, distribution, biomass, and productivity of these dominant seagrass species are discussed. Seagrass beds support a very diverse and abundant algal flora and fauna, and these organisms, and seagrass detritus form the base of a productive food chain. Seagrass beds are important nursery areas providing both cover and food, for a number of commercial and sports fishery species. Along the west Florida coast, estuarine grass beds are noticeably more stressed and impacted by human activities than the more pristine nearshore beds. Urban development and dredging and filling are the major threates to seagrass beds in this region. 500 refs., 28 figs., 14 tabs.

  5. Interannual to multidecadal climate forcings on groundwater resources of the U.S. West Coast

    USGS Publications Warehouse

    Velasco, Elzie M; Gurdak, Jason J.; Dickinson, Jesse; Ferre, T.P.A; Corona, Claudia

    2016-01-01

    Study regionThe U.S. West Coast, including the Pacific Northwest and California Coastal Basins aquifer systems.Study focusGroundwater response to interannual to multidecadal climate variability has important implications for security within the water–energy–food nexus. Here we use Singular Spectrum Analysis to quantify the teleconnections between AMO, PDO, ENSO, and PNA and precipitation and groundwater level fluctuations. The computer program DAMP was used to provide insight on the influence of soil texture, depth to water, and mean and period of a surface infiltration flux on the damping of climate signals in the vadose zone.New hydrological insights for the regionWe find that PDO, ENSO, and PNA have significant influence on precipitation and groundwater fluctuations across a north-south gradient of the West Coast, but the lower frequency climate modes (PDO) have a greater influence on hydrologic patterns than higher frequency climate modes (ENSO and PNA). Low frequency signals tend to be preserved better in groundwater fluctuations than high frequency signals, which is a function of the degree of damping of surface variable fluxes related to soil texture, depth to water, mean and period of the infiltration flux. The teleconnection patterns that exist in surface hydrologic processes are not necessarily the same as those preserved in subsurface processes, which are affected by damping of some climate variability signals within infiltrating water.

  6. A coastal hazards data base for the U.S. West Coast

    SciTech Connect

    Gornitz, V.M. |; Beaty, T.W.; Daniels, R.C.

    1997-12-01

    This document describes the contents of a digital data base that may be used to identify coastlines along the US West Coast that are at risk to sea-level rise. This data base integrates point, line, and polygon data for the US West Coast into 0.25{degree} latitude by 0.25{degree} longitude grid cells and into 1:2,000,000 digitized line segments that can be used by raster or vector geographic information systems (GIS) as well as by non-GIS data bases. Each coastal grid cell and line segment contains data variables from the following seven data sets: elevation, geology, geomorphology, sea-level trends, shoreline displacement (erosion/accretion), tidal ranges, and wave heights. One variable from each data set was classified according to its susceptibility to sea-level rise and/or erosion to form 7 relative risk variables. These risk variables range in value from 1 to 5 and may be used to calculate a Coastal Vulnerability Index (CVI). Algorithms used to calculate several CVIs are listed within this text.

  7. A report on radioactivity measurements of fish samples from the West Coast of Canada

    PubMed Central

    Chen, Jing; Cooke, Michael W.; Mercier, Jean-Francois; Ahier, Brian; Trudel, Marc; Workman, Greg; Wyeth, Malcolm; Brown, Robin

    2015-01-01

    Even though many studies have shown that radioactive caesium levels in fish caught outside of Japan were below experimental detection limits of a few Bq kg−1, significant public concern has been expressed about the safety of consuming seafood from the Pacific Ocean following the Fukushima-Daiichi nuclear accident. To address the public concerns, samples of commonly consumed salmon and groundfish harvested from the Canadian west coast in 2013 were analysed for radioactive caesium. None of the fish samples analysed in this study contained any detectable levels of 134Cs and 137Cs under given experimental setting with the average detection limit of ∼2 Bq kg−1. Using a conservative worst-case scenario where all fish samples would contain 137Cs exactly at the detection limit level and 134Cs at half of the detection limit level (to account for much shorter half-life of 134Cs), the resulting radiation dose for people from consumption of this fish would be a very small fraction of the annual dose from exposure to natural background radiation in Canada. Therefore, fish, such as salmon and groundfish, from the Canadian west coast are of no radiological health concern. PMID:24795385

  8. A report on radioactivity measurements of fish samples from the west coast of Canada.

    PubMed

    Chen, Jing; Cooke, Michael W; Mercier, Jean-Francois; Ahier, Brian; Trudel, Marc; Workman, Greg; Wyeth, Malcolm; Brown, Robin

    2015-02-01

    Even though many studies have shown that radioactive caesium levels in fish caught outside of Japan were below experimental detection limits of a few Bq kg(-1), significant public concern has been expressed about the safety of consuming seafood from the Pacific Ocean following the Fukushima-Daiichi nuclear accident. To address the public concerns, samples of commonly consumed salmon and groundfish harvested from the Canadian west coast in 2013 were analysed for radioactive caesium. None of the fish samples analysed in this study contained any detectable levels of (134)Cs and (137)Cs under given experimental setting with the average detection limit of ∼2 Bq kg(-1). Using a conservative worst-case scenario where all fish samples would contain (137)Cs exactly at the detection limit level and (134)Cs at half of the detection limit level (to account for much shorter half-life of (134)Cs), the resulting radiation dose for people from consumption of this fish would be a very small fraction of the annual dose from exposure to natural background radiation in Canada. Therefore, fish, such as salmon and groundfish, from the Canadian west coast are of no radiological health concern.

  9. Coherence of river and ocean conditions along the US West Coast during storms

    USGS Publications Warehouse

    Kniskern, T.A.; Warrick, J.A.; Farnsworth, K.L.; Wheatcroft, R.A.; Goni, M.A.

    2011-01-01

    The majority of water and sediment discharge from the small, mountainous watersheds of the US West Coast occurs during and immediately following winter storms. The physical conditions (waves, currents, and winds) within and acting upon the proximal coastal ocean during these winter storms strongly influence dispersal patterns. We examined this river-ocean temporal coherence for four coastal river-shelf systems of the US West Coast (Umpqua, Eel, Salinas, and Santa Clara) to evaluate whether specific ocean conditions occur during floods that may influence coastal dispersal of sediment. Eleven years of corresponding river discharge, wind, and wave data were obtained for each river-shelf system from USGS and NOAA historical records, and each record was evaluated for seasonal and event-based patterns. Because near-bed shear stresses due to waves influence sediment resuspension and transport, we used spectral wave data to compute and evaluate wave-generated bottom-orbital velocities. The highest values of wave energy and discharge for all four systems were consistently observed between October 15 and March 15, and there were strong latitudinal patterns observed in these data with lower discharge and wave energies in the southernmost systems. During floods we observed patterns of river-ocean coherence that differed from the overall seasonal patterns. For example, downwelling winds generally prevailed during floods in the northern two systems (Umpqua and Eel), whereas winds in the southern systems (Salinas and Santa Clara) were generally downwelling before peak discharge and upwelling after peak discharge. Winds not associated with floods were generally upwelling on all four river-shelf systems. Although there are seasonal variations in river-ocean coherence, waves generally led floods in the three northern systems, while they lagged floods in the Santa Clara. Combined, these observations suggest that there are consistent river-ocean coherence patterns along the US West

  10. Source location impact on relative tsunami strength along the U.S. West Coast

    NASA Astrophysics Data System (ADS)

    Rasmussen, L.; Bromirski, P. D.; Miller, A. J.; Arcas, D.; Flick, R. E.; Hendershott, M. C.

    2015-07-01

    Tsunami propagation simulations are used to identify which tsunami source locations would produce the highest amplitude waves on approach to key population centers along the U.S. West Coast. The reasons for preferential influence of certain remote excitation sites are explored by examining model time sequences of tsunami wave patterns emanating from the source. Distant bathymetric features in the West and Central Pacific can redirect tsunami energy into narrow paths with anomalously large wave height that have disproportionate impact on small areas of coastline. The source region generating the waves can be as little as 100 km along a subduction zone, resulting in distinct source-target pairs with sharply amplified wave energy at the target. Tsunami spectral ratios examined for transects near the source, after crossing the West Pacific, and on approach to the coast illustrate how prominent bathymetric features alter wave spectral distributions, and relate to both the timing and magnitude of waves approaching shore. To contextualize the potential impact of tsunamis from high-amplitude source-target pairs, the source characteristics of major historical earthquakes and tsunamis in 1960, 1964, and 2011 are used to generate comparable events originating at the highest-amplitude source locations for each coastal target. This creates a type of "worst-case scenario," a replicate of each region's historically largest earthquake positioned at the fault segment that would produce the most incoming tsunami energy at each target port. An amplification factor provides a measure of how the incoming wave height from the worst-case source compares to the historical event.

  11. Learning Across Disciplines: An Approach to West African Music.

    ERIC Educational Resources Information Center

    Morin, Francine

    2003-01-01

    Describes how to teach about world music, specifically music of West Africa, using an interdisciplinary inquiry approach. Explains that questions are generated and the teacher develops the learning experience. Provides examples at the fourth grade level as well as information on resources and musical examples. (CMK)

  12. West-African trypanosomiasis in a returned traveller from Ghana: an unusual cause of progressive neurological decline.

    PubMed

    Elliott, Ivo; Patel, Trupti; Shah, Jagrit; Venkatesan, Pradhib

    2014-08-14

    West-African trypanosomiasis caused by Trypanosoma brucei gambiense is a rare imported infection presenting with somnolence, lymphadenopathy and wide-ranging neurological symptoms. A 67-year-old Caucasian man presented with a 10-month history of cognitive deterioration, ataxic gait, somnolence and urinary incontinence. His symptoms had progressed more rapidly over the course of a month prior to admission. Serological testing confirmed a diagnosis of West-African trypanosomiasis. The patient was successfully treated with eflornithine and made a good recovery. West-African trypanosomiasis should be considered in the differential diagnosis of unexplained cognitive decline in those with a relevant travel history. If left untreated, the condition is universally fatal.

  13. Orographic shaping of US West Coast wind profiles during the upwelling season

    NASA Astrophysics Data System (ADS)

    Renault, Lionel; Hall, Alex; McWilliams, James C.

    2016-01-01

    Spatial and temporal variability of nearshore winds in eastern boundary current systems is affected by orography, coastline shape, and air-sea interaction. These lead to a weakening of the wind close to the coast: the so-called wind drop-off. In this study, regional atmospheric simulations over the US West Coast are used to demonstrate monthly characteristics of the wind drop-off and assess the mechanisms controlling it. Using a long-term simulation, we show the wind drop-off has spatial and seasonal variability in both its offshore extent and intensity. The offshore extent varies from around 10 to 80 km from the coast and the wind reduction from 10 to 80 %. We show that when the mountain orography is combined with the coastline shape of a cape, it has the biggest influence on wind drop-off. The primary associated processes are the orographically-induced vortex stretching and the surface drag related to turbulent momentum flux divergence that has an enhanced drag coefficient over land. Orographically-induced tilting/twisting can also be locally significant in the vicinity of capes. The land-sea drag difference acts as a barrier to encroachment of the wind onto the land through turbulent momentum flux divergence. It turns the wind parallel to the shore and slightly reduces it close to the coast. Another minor factor is the sharp coastal sea surface temperature front associated with upwelling. This can weaken the surface wind in the coastal strip by shallowing the marine boundary layer and decoupling it from the overlying troposphere.

  14. Exploring HIV knowledge, risk and protective factors among west African forced migrants in New York City.

    PubMed

    Akinsulure-Smith, Adeyinka M

    2014-06-01

    Because of ongoing political and social instability throughout the continent, many Africans have become forced migrants. Unlike immigrants who choose to migrate, forced migrants flee their countries in search of safety and often endure multiple traumatic events during their migration. They are often unprepared for new risks in their adopted country. There is a high incidence of newly-diagnosed HIV cases among West African immigrants in the New York City metropolitan area, but little research to date to understand why this might occur. In order to gain insight, the current pilot study explored HIV knowledge, risk and protective behaviors among 52 West African-born forced migrants in New York City. HIV risk behavior came primarily from unprotected heterosexual activities. While most participants were very knowledgeable about HIV transmission and risk factors, almost half reported that they had not used condoms during sexual activities in the past 6 months. Women were more knowledgeable about HIV transmission, yet reported significantly more STDs than men. Many participants did not know about HIV/AIDS treatments and could not identify HIV/AIDS services and resources within their immigrant communities. Factors influencing HIV risk and protective behaviors among this population are identified and discussed. Suggestions for future research and strategies to reduce risky behaviors while enhancing protective ones among forced West African migrants are highlighted.

  15. Recent climatological trend of the Saharan heat low and its impact on the West African climate

    NASA Astrophysics Data System (ADS)

    Lavaysse, Christophe; Flamant, Cyrille; Evan, Amato; Janicot, Serge; Gaetani, Marco

    2015-10-01

    The Saharan heat low (SHL) plays a pivotal role in the West African monsoon system in spring and summer. The recent trend in SHL activity has been analysed using two sets of numerical weather prediction (NWP) model reanalyses and Atmospheric Models Intercomparison Project simulations from 15 climate models performed in the framework of the 5th Coupled Models Intercomparison Project (CMIP5) exercise. A local increase of temperature in the Sahara during the 90s is found in the two sets of NWP models temperature. This increase is stronger within the SHL region than over the surrounding areas. Using different temporal filters (under 25 days, 25-100 days and above 300 days), we show that this is accompanied by a slight but widespread increase of temperature, and a change in the filtered signal under 25 days during the transition period of the 90s. We also show that SHL pulsations occurring at different time scales impact the West Africa climate on a variety of spatial scales, from the regional scale (for the high band pass) to the synoptic scale (for the low band pass signal). Despite a large variability in the temporal trends for 15 climate models from the CMIP5 project, the warming trend in the 90s is observed in the models ensemble mean. Nevertheless, large discrepancies are found between the NWP models reanalyses and the climate model simulations regarding the spatial and temporal evolutions of the SHL as well as its impact on West African climate at the different time scales. These comparisons also reveal that climate models represent the West African monsoon interactions with SHL pulsations quite differently. We provide recommendations to use some of them depending on the time scales of the processes at play (synoptic, seasonal, interannual) and based on key SHL metrics (location, mean intensity, global trend, interaction with the West African monsoon dynamics).

  16. Viruses other than arenaviruses from West African wild mammals

    PubMed Central

    Kemp, Graham E.

    1975-01-01

    At least thirty-seven different viruses have been isolated from wild mammals in West Africa since 1962. Some of these, including Lassa virus, are already known to cause serious human morbidity and mortality. Crimean haemorrhagic fever-Congo virus, Dugbe virus, Mokola virus, and a smallpox-like agent from a gerbil in Dahomey are briefly discussed. An account of social and ecologic factors affecting man, domestic animals, and their interaction with wild mammals is given. PMID:1085217

  17. A springtime comparison of tropospheric ozone and transport pathways on the east and west coasts of the United States

    NASA Astrophysics Data System (ADS)

    Cooper, O. R.; Stohl, A.; Eckhardt, S.; Parrish, D. D.; Oltmans, S. J.; Johnson, B. J.; NéDéLec, P.; Schmidlin, F. J.; Newchurch, M. J.; Kondo, Y.; Kita, K.

    2005-03-01

    We have conducted a study to determine the influence of Asian pollution plumes on free tropospheric ozone above the west coast of the United States during spring. We also explored the additional impact of North American emissions on east coast free tropospheric ozone. Long-term ozone monitoring sites in the United States are few, but we obtained ozonesonde profiles from Trinidad Head on the west coast, Huntsville, Alabama, in the southeast, and Wallops Island, Virginia, on the east coast. Additional east coast ozone profiles were measured by the MOZAIC commercial aircraft at Boston, New York City, and Philadelphia. Kilometer-averaged ozone was compared between Trinidad Head and the three east coast sites (MOZAIC, Wallops Island, and Huntsville). Only in the 0-1 km layer did the MOZAIC site have a statistically significant greater amount of ozone than Trinidad Head. Likewise only the 0-1 and 1-2 km layers had greater ozone at Wallops Island and Huntsville in comparison to Trinidad Head. While Wallops Island did show greater ozone than Trinidad Head at 6-9 km, this excess ozone was attributed to a dry air mass sampling bias. A particle dispersion model was used to determine the surface source regions for each case, and the amount of anthropogenic NOx tracer that would have been emitted into each air mass. Transport times were limited to 20 days to focus on the impact of direct transport of pollution plumes from the atmospheric boundary layer. As expected, the amount of NOx tracer emitted into the east coast profiles was much greater in the lower and mid troposphere than at the west coast. At various altitudes at both coasts there existed a significant positive correlation between ozone and the NOx tracer, but the explained variance was generally less than 30%. On the east coast, Wallops Island had the weakest relationship between ozone and the NOx tracer, while Huntsville had the strongest. During spring, differences in photochemistry and transport pathways in the

  18. Above ground biomass estimation from lidar and hyperspectral airbone data in West African moist forests.

    NASA Astrophysics Data System (ADS)

    Vaglio Laurin, Gaia; Chen, Qi; Lindsell, Jeremy; Coomes, David; Cazzolla-Gatti, Roberto; Grieco, Elisa; Valentini, Riccardo

    2013-04-01

    The development of sound methods for the estimation of forest parameters such as Above Ground Biomass (AGB) and the need of data for different world regions and ecosystems, are widely recognized issues due to their relevance for both carbon cycle modeling and conservation and policy initiatives, such as the UN REDD+ program (Gibbs et al., 2007). The moist forests of the Upper Guinean Belt are poorly studied ecosystems (Vaglio Laurin et al. 2013) but their role is important due to the drier condition expected along the West African coasts according to future climate change scenarios (Gonzales, 2001). Remote sensing has proven to be an effective tool for AGB retrieval when coupled with field data. Lidar, with its ability to penetrate the canopy provides 3D information and best results. Nevertheless very limited research has been conducted in Africa tropical forests with lidar and none to our knowledge in West Africa. Hyperspectral sensors also offer promising data, being able to evidence very fine radiometric differences in vegetation reflectance. Their usefulness in estimating forest parameters is still under evaluation with contrasting findings (Andersen et al. 2008, Latifi et al. 2012), and additional studies are especially relevant in view of forthcoming satellite hyperspectral missions. In the framework of the EU ERC Africa GHG grant #247349, an airborne campaign collecting lidar and hyperspectral data has been conducted in March 2012 over forests reserves in Sierra Leone and Ghana, characterized by different logging histories and rainfall patterns, and including Gola Rainforest National Park, Ankasa National Park, Bia and Boin Forest Reserves. An Optech Gemini sensor collected the lidar dataset, while an AISA Eagle sensor collected hyperspectral data over 244 VIS-NIR bands. The lidar dataset, with a point density >10 ppm was processed using the TIFFS software (Toolbox for LiDAR Data Filtering and Forest Studies)(Chen 2007). The hyperspectral dataset, geo

  19. Plesionika sanctaecatalinae Wicksten, 1983 (Crustacea Decapoda Caridea Pandalidae) from off the west coast of Pacific Mexico.

    PubMed

    Hendrickx, Michel E

    2016-01-01

    A large series of specimens of Plesionika sanctaecatalinae was obtained during sampling operations off the west coast of the Baja California Peninsula in 2012 and 2014 (TALUD cruises). This material was examined and compared to the original description, the holotype and two paratypes. Although the fresh material fit well with the type material examined, some discrepancies were noted in the illustrations of the original description, particularly regarding scaphocerite and the telson, and new illustrations are provided. The series of sample available from the TALUD cruises allow to increase considerably the number of localities known for this species in the California Current area. A series of unpublished records corresponding to material examined in the original description but not listed in details, allows for further increase of the number of reported localities where P. sanctaecatalinae has been collected. Its vertical distribution in the water column, however, remains unclear due to the fact that no discrete samples are available for this species. PMID:27395100

  20. Site specific probabilistic seismic hazard analysis at Dubai Creek on the west coast of UAE

    NASA Astrophysics Data System (ADS)

    Shama, Ayman A.

    2011-03-01

    A probabilistic seismic hazard analysis (PSHA) was conducted to establish the hazard spectra for a site located at Dubai Creek on the west coast of the United Arab Emirates (UAE). The PSHA considered all the seismogenic sources that affect the site, including plate boundaries such as the Makran subduction zone, the Zagros fold-thrust region and the transition fault system between them; and local crustal faults in UAE. PSHA indicated that local faults dominate the hazard. The peak ground acceleration (PGA) for the 475-year return period spectrum is 0.17 g and 0.33 g for the 2,475-year return period spectrum. The hazard spectra are then employed to establish rock ground motions using the spectral matching technique.

  1. HPLC profiling of antimicrobial and antioxidant phyco sugars isolated from the South West coast of India.

    PubMed

    Kailas, Abhilash Parameswaran; Nair, Sukumaran Muraleedharan

    2016-10-20

    Phyco sugars isolated from the South West coast of India are commercially and therapeutically interesting due to their various biological activities. These sugars were isolated from six (three red and three green) seaweed species using water at 100°C followed by precipitation using ethanol. The physical, chemical and biological characteristics were explored with specific highlights onto the specific rotation, HPLC-RI sugar speciation, antioxidant and antimicrobial activities. The biological properties were evaluated based on multiple methods and standards, such that the actual nature of the sugar is understood. G. corticata var. cylindrica (31.66%) had the highest sugar content. All the sugars had levo rotatory specific rotation and interesting chemical characteristics. Sugars isolated had competitive biological activities and had the presence of seven monosaccharides and one disaccharide. The results highlighted the socio-economic importance of seaweeds which could be developed as a potential source of bioactive compounds in the upcoming future. PMID:27474603

  2. MLR and ANN models of significant wave height on the west coast of India

    NASA Astrophysics Data System (ADS)

    Asma, Senay; Sezer, Ahmet; Ozdemir, Ozer

    2012-12-01

    Multiple linear regression (MLR) and artificial neural network (ANN) models are used in the present work to describe the significant wave height off Goa, located in the west Indian coast. A comparison study was carried out with the purpose of verifying when the artificial neural network and multiple linear regression models are appropriate for prediction of the significant wave height. Discussions of advantages and disadvantages are given in different point of view for both the methods. Several meteorological factors are used during the analysis and the ones affecting more to the model are kept. We concluded that non-linear models with wind speed and wind gust at a previous time step and air pressure, water temperature and air temperature at the same time step yield to better significant wave height models.

  3. Mineralogical, crystallographic and morphological characteristics of natural kaolins from the Ivory Coast (West Africa)

    NASA Astrophysics Data System (ADS)

    Sei, J.; Morato, F.; Kra, G.; Staunton, S.; Quiquampoix, H.; Jumas, J. C.; Olivier-Fourcade, J.

    2006-10-01

    Thirteen clay samples from four deposits in the Ivory Coast (West Africa) were studied using X-ray diffraction, thermogravimetric analysis and chemical analysis. Mineralogical, crystallographic and morphological characteristics of these samples are given. Kaolinite is the principal mineral but other minerals are present in small quantities: illite, quartz, anatase and iron oxides (oxides and oxyhydroxides). The crystallographic, morphological and surface characteristics are influenced by the presence of these impurities. In particular, the presence of iron oxides was associated with reduced structural ordering and thermal stability of kaolinite and increased specific surface area. These clays could be used in the ceramics industry to make tiles and bricks, and also in agronomy as supports for chemical fertilizers or for environmental protection by immobilising potentially toxic waste products.

  4. Plesionika sanctaecatalinae Wicksten, 1983 (Crustacea Decapoda Caridea Pandalidae) from off the west coast of Pacific Mexico.

    PubMed

    Hendrickx, Michel E

    2016-05-17

    A large series of specimens of Plesionika sanctaecatalinae was obtained during sampling operations off the west coast of the Baja California Peninsula in 2012 and 2014 (TALUD cruises). This material was examined and compared to the original description, the holotype and two paratypes. Although the fresh material fit well with the type material examined, some discrepancies were noted in the illustrations of the original description, particularly regarding scaphocerite and the telson, and new illustrations are provided. The series of sample available from the TALUD cruises allow to increase considerably the number of localities known for this species in the California Current area. A series of unpublished records corresponding to material examined in the original description but not listed in details, allows for further increase of the number of reported localities where P. sanctaecatalinae has been collected. Its vertical distribution in the water column, however, remains unclear due to the fact that no discrete samples are available for this species.

  5. NOAA/West coast and Alaska Tsunami warning center Atlantic Ocean response criteria

    USGS Publications Warehouse

    Whitmore, P.; Refidaff, C.; Caropolo, M.; Huerfano-Moreno, V.; Knight, W.; Sammler, W.; Sandrik, A.

    2009-01-01

    West Coast/Alaska Tsunami Warning Center (WCATWC) response criteria for earthquakesoccurring in the Atlantic and Caribbean basins are presented. Initial warning center decisions are based on an earthquake's location, magnitude, depth, distance from coastal locations, and precomputed threat estimates based on tsunami models computed from similar events. The new criteria will help limit the geographical extent of warnings and advisories to threatened regions, and complement the new operational tsunami product suite. Criteria are set for tsunamis generated by earthquakes, which are by far the main cause of tsunami generation (either directly through sea floor displacement or indirectly by triggering of sub-sea landslides).The new criteria require development of a threat data base which sets warning or advisory zones based on location, magnitude, and pre-computed tsunami models. The models determine coastal tsunami amplitudes based on likely tsunami source parameters for a given event. Based on the computed amplitude, warning and advisory zones are pre-set.

  6. The West African Ebola outbreak: finishing the job, preparing for future.

    PubMed

    Parsons, Clare; Naeem Ahmad, Umar

    2015-08-01

    As the West African Ebola Outbreak moves towards the final stages, we must consider the importance of remaining work and take heed of lessons learned in preparation for future outbreaks. Several issues pertinent to preparedness must be considered, including the remaining animal reservoir and potential for sexual transmission. Testing must be accessible and contact tracing robust to trace the last patient. Improved infection control procedures alongside education and training require guaranteed supply chains and ongoing funding. Effort must be sustained to prevent an even greater catastrophe than the one inflicted on West Africa today. PMID:26160255

  7. Deep crustal structure of the North-West African margin from combined wide-angle and reflection seismic data (MIRROR seismic survey)

    NASA Astrophysics Data System (ADS)

    Biari, Y.; Klingelhoefer, F.; Sahabi, M.; Aslanian, D.; Schnurle, P.; Berglar, K.; Moulin, M.; Mehdi, K.; Graindorge, D.; Evain, M.; Benabdellouahed, M.; Reichert, C.

    2015-08-01

    The structure of the Moroccan and Nova Scotia conjugate rifted margins is of key importance for understanding the Mesozoic break-up and evolution of the northern central Atlantic Ocean basin. Seven combined multichannel reflection (MCS) and wide-angle seismic (OBS) data profiles were acquired along the Atlantic Moroccan margin between the latitudes of 31.5° and 33° N during the MIRROR seismic survey in 2011, in order to image the transition from continental to oceanic crust, to study the variation in crustal structure, and to characterize the crust under the West African Coast Magnetic Anomaly (WACMA). The data were modeled using a forward modeling approach. The final models image crustal thinning from 36 km thickness below the continent to approximately 8 km in the oceanic domain. A 100 km wide zone characterized by rough basement topography and high seismic velocities up to 7.4 km/s in the lower crust is observed westward of the West African Coast Magnetic Anomaly. No basin underlain by continental crust has been imaged in this region, as has been identified north of our study area. Comparison to the conjugate Nova Scotian margin shows a similar continental crustal thickness and layer geometry, and the existence of exhumed and serpentinized upper mantle material on the Canadian side only. The oceanic crustal thickness is lower on the Canadian margin.

  8. Evidence of Henipavirus Infection in West African Fruit Bats

    PubMed Central

    Hayman, David T. S.; Suu-Ire, Richard; Breed, Andrew C.; McEachern, Jennifer A.; Wang, Linfa; Wood, James L. N.; Cunningham, Andrew A.

    2008-01-01

    Henipaviruses are emerging RNA viruses of fruit bat origin that can cause fatal encephalitis in man. Ghanaian fruit bats (megachiroptera) were tested for antibodies to henipaviruses. Using a Luminex multiplexed microsphere assay, antibodies were detected in sera of Eidolon helvum to both Nipah (39%, 95% confidence interval: 27–51%) and Hendra (22%, 95% CI: 11–33%) viruses. Virus neutralization tests further confirmed seropositivity for 30% (7/23) of Luminex positive serum samples. Our results indicate that henipavirus is present within West Africa. PMID:18648649

  9. West African Ebola epidemic: lessons and a call to action

    PubMed Central

    Ameme, Donne Kofi

    2015-01-01

    The current Ebola epidemic in West Africa is unprecedented in terms of magnitude and spread. A year after the index case had been identified in a remote village in Guinea, over 17,000 cases and 6,000 deaths were reported in Africa and beyond. Many interventions have been implemented but the outbreak rages on. This paper examines key gaps in the interventions and calls for evidence-based actions to reverse the trend and prevent future epidemics of this proportion. PMID:26740834

  10. New residence times of the Holocene reworked shells on the west coast of Bohai Bay, China

    NASA Astrophysics Data System (ADS)

    Shang, Zhiwen; Wang, Fu; Li, Jianfen; Marshall, William A.; Chen, Yongsheng; Jiang, Xingyu; Tian, Lizhu; Wang, Hong

    2016-01-01

    Shelly cheniers and shell-rich beds found intercalated in near-shore marine muds and sandy sediments can be used to indicate the location of ancient shorelines, and help to estimate the height of sea level. However, dating the deposition of material within cheniers and shell-rich beds is not straightforward because much of this material is transported and re-worked, creating an unknown temporal off-set, i.e., the residence time, between the death of a shell and its subsequent entombment. To quantify the residence time during the Holocene on a section of the northern Chinese coastline a total 47 shelly subsamples were taken from 17 discrete layers identified on the west coast of Bohai Bay. This material was AMS 14C dated and the calibrated ages were systematically compared. The subsamples were categorized by type as articulated and disarticulated bivalves, gastropod shells, and undifferentiated shell-hash. It was found that within most individual layers the calibrated ages of the subsamples got younger relative to the amount of apparent post-mortem re-working the material had been subject to. For examples, the 14C ages of the bivalve samples trended younger in this order: shell-hash → split shells → articulated shells. We propose that the younger subsample age determined within an individual layer will be the closest to the actual depositional age of the material dated. Using this approach at four Holocene sites we find residence times which range from 100 to 1260 cal yrs, with two average values of 600 cal yrs for the original 14C dates older than 1 ka cal BP and 100 cal yrs for the original 14C dates younger than 1 ka cal BP, respectively. Using this semi-empirical estimation of the shell residence times we have refined the existing chronology of the Holocene chenier ridges on the west coast of Bohai Bay.

  11. The message, meteorology and myths of the historic West Coast winter flooding of 1861 - 62

    NASA Astrophysics Data System (ADS)

    Schick, L. J.

    2012-12-01

    The greatest known recorded flooding, ever to impact the West Coast of the United States, occurred during the winter of 1861-1862. In fact, the extraordinary flood flows on five major rivers, remain the record peaks to this day. The flooding was caused by a series of Pacific mid-latitude cyclones and several strong atmospheric rivers. The extreme rainy pattern initially strikes Oregon. The high water causes the flood of record on the Willamette River, with extensive devastation, wiping out several major towns along the river. Communications, food and supplies were cut off for much of the winter in Oregon.The intense wet weather, then redevelops, moves south and stalls - pummeling Northern California with major flooding. The runoff fills California's Central Valley with a huge inland lake. Sacramento is submerged, turned into what was described as a "frontier Venice". Flood damages eliminate a large part of the state's tax base.Finally the stormy pattern shifts into Southern California, producing major flooding. Most of lowland Los Angeles, Orange and San Diego Counties are flooded under several feet of water for weeks.The author researched limited weather data, historical accounts, maps and ship reports to reconstruct this series of storms and their effects along the West Coast. The extent and evolution of this series of flood events is unprecedented. Myths regarding the causes of this flooding are common, but its sheer magnitude is undisputable. This presentation will also demonstrate the nature and impacts of these consecutive major flood events, while revealing the lessons to be learned in light of advances in modern forecasting techniques.

  12. Climatic and Anthropogenic Controls on Correlated Discharge from US West Coast Rivers (Invited)

    NASA Astrophysics Data System (ADS)

    Farnsworth, K. L.; Kniskern, T. A.

    2013-12-01

    Most river basins along the US West Coast are generally small, less than 15,000 km2, and tend to flood quickly following rain events. The storm systems that deliver rain to the coastal mountain ranges are considerably larger than the river basins such that multiple basins receive precipitation within hours of each other. Subsequently, these proximal rivers often disperse freshwater and sediment to the coastal ocean at relatively the same time. Many conceptual and numerical models of coastal processes may underestimate the delivery, dispersal and burial of sediment on the continental shelves as they often assume point source delivery of water and sediment from a single river. The reality seems to speak to the fact that a collection of smaller river basins may be synchronously delivering sediment all along a stretch of coastline. Hydrologic records from 62 coastal watersheds stretching along the US west coast from the Canadian to the Mexican border were acquired from the USGS river gauging network, this included over 100 gauging stations with records varying in length. This data mining effort allowed for a detailed analysis of the timing of flood peaks to the actual coastlines, rather than just correlation between gauging stations. Distinct coastal groupings were found that have rivers that deliver freshwater and sediment to the continental shelves at the same time, indicating plume mixing and different oceanic hydrodynamic regimes than would be indicated by traditional coastal sediment transport models. Also seen were larger scale climatic controls on the watershed relationships and alteration of the flood signals due to anthropogenic changes within the watershed. Extensive flood control networks, differences in population centers and floodplain modification within these basins all contributed to unexpected deviations from the correlation patterns.

  13. Port Eliza cave: North American West Coast interstadial environment and implications for human migrations

    NASA Astrophysics Data System (ADS)

    Ward, B. C.; Wilson, M. C.; Nagorsen, D. W.; Nelson, D. E.; Driver, J. C.; Wigen, R. J.

    2003-06-01

    The timing of Late Pleistocene glacial advance, retreat, relative sea level and environmental viability between 25 and 12.5 ka ( 14C yrs BP) remain a key issue in the feasibility of a coastal migration route for the first North Americans. This is discussed on the basis of stratigraphic, radiometric and faunal data for Port Eliza cave, a raised sea cave, on the west coast of Vancouver Island, British Columbia. Ice cover is indicated by the occurrence of 2 m of laminated clay, representing deposition in a subglacial lake. From immediately below this clay a diverse vertebrate fauna of marmot, vole, marten, cervid and various species of birds and fish was recovered, yielding ages of 18-16 ka. These dates and others from the region show that ice cover on the outer coast was brief, from ca 15.5-14 ka. The fish species indicate that relative sea level was close to the cave and that salmon runs were likely present. The terrestrial vertebrate fauna is consistent with a cool, open parkland environment with maximum summer temperatures cooler than present; these conditions lasted until at least 16 ka. With a diverse fauna and favorable climate, humans could have survived here on a mixed marine-terrestrial diet, confirming the viability of the coastal migration hypothesis for this portion of the route.

  14. NOAA/West Coast and Alaska Tsunami Warning Center Pacific Ocean response criteria

    USGS Publications Warehouse

    Whitmore, P.; Benz, H.; Bolton, M.; Crawford, G.; Dengler, L.; Fryer, G.; Goltz, J.; Hansen, R.; Kryzanowski, K.; Malone, S.; Oppenheimer, D.; Petty, E.; Rogers, G.; Wilson, Jim

    2008-01-01

    New West Coast/Alaska Tsunami Warning Center (WCATWC) response criteria for earthquakes occurring in the Pacific basin are presented. Initial warning decisions are based on earthquake location, magnitude, depth, and - dependent on magnitude - either distance from source or precomputed threat estimates generated from tsunami models. The new criteria will help limit the geographical extent of warnings and advisories to threatened regions, and complement the new operational tsunami product suite. Changes to the previous criteria include: adding hypocentral depth dependence, reducing geographical warning extent for the lower magnitude ranges, setting special criteria for areas not well-connected to the open ocean, basing warning extent on pre-computed threat levels versus tsunami travel time for very large events, including the new advisory product, using the advisory product for far-offshore events in the lower magnitude ranges, and specifying distances from the coast for on-shore events which may be tsunamigenic. This report sets a baseline for response criteria used by the WCATWC considering its processing and observational data capabilities as well as its organizational requirements. Criteria are set for tsunamis generated by earthquakes, which are by far the main cause of tsunami generation (either directly through sea floor displacement or indirectly by triggering of slumps). As further research and development provides better tsunami source definition, observational data streams, and improved analysis tools, the criteria will continue to adjust. Future lines of research and development capable of providing operational tsunami warning centers with better tools are discussed.

  15. Macrofauna associated with temporary Sabellaria alveolata reefs on the west coast of Cotentin (France).

    PubMed

    Schlund, Erika; Basuyaux, Olivier; Lecornu, Billie; Pezy, Jean-Philippe; Baffreau, Alexandrine; Dauvin, Jean-Claude

    2016-01-01

    The polychaete Sabellaria alveolata (Linnaeus, 1767) is an important ecosystem engineer building reef structures which add to the topographic complexity in colonized areas. In Europe, the most extensive reef formation is located in the Bay of Mont-Saint-Michel (France). Since 2006, Sabellaria bio-constructions have developed on hard substrates along the west coast of the Cotentin Peninsula between Champeaux and Saint-Germain-sur-Ay on the northern part of the Bay of Mont-Saint-Michel. In this sector, two distinct types of bio-construction can be distinguished: platforms and reefs. The aim of this study is to analyse the patterns of the associated macrofauna on these platforms and reefs, as well as outside, and test for a correlation between the presence of Sabellaria bio-constructions and the richness of the benthic macrofauna. Univariate analyses are used to compare the macrofauna on four sites (Champeaux, Lingreville, Blainville-sur-Mer and Saint-Germain-sur-Ay). The results show a higher taxonomic richness on the platform-type than on the reef-type structures, and also a higher taxonomic richness outside the bio-construction areas. This suggests that, on the examined sites, the presence of S. alveolata bio-constructions does not contribute to higher levels of benthic macrofaunal richness on hard substrates. Temporary bio-constructions along this coast exhibit reefs of interest at some sites as well as in very small zones which merit special attention. PMID:27536543

  16. Macrofauna associated with temporary Sabellaria alveolata reefs on the west coast of Cotentin (France).

    PubMed

    Schlund, Erika; Basuyaux, Olivier; Lecornu, Billie; Pezy, Jean-Philippe; Baffreau, Alexandrine; Dauvin, Jean-Claude

    2016-01-01

    The polychaete Sabellaria alveolata (Linnaeus, 1767) is an important ecosystem engineer building reef structures which add to the topographic complexity in colonized areas. In Europe, the most extensive reef formation is located in the Bay of Mont-Saint-Michel (France). Since 2006, Sabellaria bio-constructions have developed on hard substrates along the west coast of the Cotentin Peninsula between Champeaux and Saint-Germain-sur-Ay on the northern part of the Bay of Mont-Saint-Michel. In this sector, two distinct types of bio-construction can be distinguished: platforms and reefs. The aim of this study is to analyse the patterns of the associated macrofauna on these platforms and reefs, as well as outside, and test for a correlation between the presence of Sabellaria bio-constructions and the richness of the benthic macrofauna. Univariate analyses are used to compare the macrofauna on four sites (Champeaux, Lingreville, Blainville-sur-Mer and Saint-Germain-sur-Ay). The results show a higher taxonomic richness on the platform-type than on the reef-type structures, and also a higher taxonomic richness outside the bio-construction areas. This suggests that, on the examined sites, the presence of S. alveolata bio-constructions does not contribute to higher levels of benthic macrofaunal richness on hard substrates. Temporary bio-constructions along this coast exhibit reefs of interest at some sites as well as in very small zones which merit special attention.

  17. Chemical and Biological Impacts of Ocean Acidification Along the West Coast of North America

    NASA Astrophysics Data System (ADS)

    Feely, R. A.; Alin, S. R.; Carter, B.; Bednarsek, N.

    2015-12-01

    The continental shelf region off the Washington-Oregon-California coast is seasonally exposed to water with a low aragonite saturation state by coastal upwelling of CO2-rich waters. To date, the spatial and temporal distribution of anthropogenic CO2 (Canth) contribution to the CO2-rich waters is largely unknown. Here we use an adaptation of the linear regression approach described in Feely et al. (2008) to utilize the GO-SHIP Repeat Hydrography data set from the northeast Pacific to establish an annually updated relationship between Canth and potential density. This relationship was then used with the NOAA Ocean Acidification Program West Coast cruise data sets from 2007, 2011, 2012 and 2013 to determine the spatial variations of Canth in the upwelled water. Our results show large spatial differences in Canth in surface waters along the coast with the lowest values (40-45 μmol kg-1) in strong upwelling regions of off northern California and southern Oregon and higher values (50-70 μmol kg-1) to the north and south of this region. Canth contributes an average of about 70 % of the increased amount of dissolved inorganic carbon in the upwelled waters at the surface relative to what would be expected from physical circulation and exchange with a preindustrial atmosphere alone. In contrast, Canth contributes an average of about 31%, and 16% of the increased amount of dissolved inorganic carbon at 50 m depth, and at 100 m depth respectively. The remaining contributions are either due to respiration processes in the water that was upwelled and transported to coastal regions or respiration processes that occurs locally during the course of the upwelling season. The uptake of Canth has caused the aragonite saturation horizon to shoal by approximately 30-50 m since preindustrial period so that the undersaturated waters are well within the regions of the continental shelf that affect the biological communities.

  18. 50 CFR 600.525 - Applicability of subpart F to Canadian Albacore Fishing Vessels off the West Coast.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 8 2010-10-01 2010-10-01 false Applicability of subpart F to Canadian Albacore Fishing Vessels off the West Coast. 600.525 Section 600.525 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE...

  19. 50 CFR Table 3 to Part 660, Subpart C - Vessel Capacity Ratings for West Coast Groundfish Limited Entry Permits

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 13 2014-10-01 2014-10-01 false Vessel Capacity Ratings for West Coast Groundfish Limited Entry Permits 3 Table 3 to Part 660, Subpart C Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE...

  20. Eight years of regional scale, benthic assessments of the U.S. West Coast: Lessons learned and future directions

    EPA Science Inventory

    The EPA National Coastal Assessment (NCA) conducted regional scale assessments of benthic condition for the US West Coast from Washington to California, several regions of Alaska, Hawaii, and the Trust Territories of Guam and American Samoa. Over an 8-year period, studies focuse...

  1. The food of Near East, North West and Western African regions.

    PubMed

    Burlingame, Barbara

    2003-01-01

    Among the countries that can be classified as Near East Africa, North West Africa, and Western Africa, there is a great diversity of foods and dietary patterns. Prevalence of undernourishment as defined by FAO using dietary energy supply data, varies dramatically among these countries, with Tunisia in the lowest prevalence category (<2.5%), and Sierra Leone in the highest prevalence category (>35%). Throughout the 1960's, the dietary energy supply of North West African and Western African countries was similar. However, since the 1970s a great and consistent improvement has been seen in North and North West African countries. Both the proportion and number of undernourished in North Africa is now very similar to that of North America. Oil use, energy from fat, and protein from plant versus animal sources account for a large part of the food pattern differences between countries in these regions. Using Tunisia and Sierra Leone as examples again, dietary diversity as measured by the percentage of energy from foods other than starchy staples, is about 50% in the former, while in the latter, it is only 36%. Fatty fruits such as olives, cocoa and palm fruit have a special role in both the diet and the economies of the region. PMID:14505995

  2. The food of Near East, North West and Western African regions.

    PubMed

    Burlingame, Barbara

    2003-01-01

    Among the countries that can be classified as Near East Africa, North West Africa, and Western Africa, there is a great diversity of foods and dietary patterns. Prevalence of undernourishment as defined by FAO using dietary energy supply data, varies dramatically among these countries, with Tunisia in the lowest prevalence category (<2.5%), and Sierra Leone in the highest prevalence category (>35%). Throughout the 1960's, the dietary energy supply of North West African and Western African countries was similar. However, since the 1970s a great and consistent improvement has been seen in North and North West African countries. Both the proportion and number of undernourished in North Africa is now very similar to that of North America. Oil use, energy from fat, and protein from plant versus animal sources account for a large part of the food pattern differences between countries in these regions. Using Tunisia and Sierra Leone as examples again, dietary diversity as measured by the percentage of energy from foods other than starchy staples, is about 50% in the former, while in the latter, it is only 36%. Fatty fruits such as olives, cocoa and palm fruit have a special role in both the diet and the economies of the region.

  3. Concentrations of Cu and Pb in the offshore and intertidal sediments of the west coast of Peninsular Malaysia.

    PubMed

    Yap, C K; Ismail, A; Tan, S G; Omar, H

    2002-12-01

    Malaysia is now a developing country and on her way towards being an industrialised one by the year 2020. Most of her industries and urban areas are located on the west coast of Peninsular Malaysia. In addition, the offshore area of the west coast is now one of the busiest shipping lanes in the world. These two phenomena make the intertidal and offshore areas of the west coast of Peninsular Malaysia interesting for scientific studies. Therefore, this study focused on both the offshore and intertidal sediments of the west coast of Peninsular Malaysia. Sampling for sediment samples were done from the northern to the southern ends of the peninsula and these sediment samples were analysed for Cu and Pb. It was found that total Cu concentrations ranged from 0.25 to 13.8 and 0.40 to 315 microg/g dry weight (dw) for offshore and intertidal sediments, respectively. For Pb, it ranged from 3.59 to 25.4 and 0.96 to 69.8 microg/g dw for the offshore and intertidal sediments, respectively. The ranges of Cu and Pb found from the west coast of Peninsular Malaysia were low in comparison to regional data. However, some intertidal areas were identified as receiving anthropogenic Cu and Pb. Geochemical studies revealed that the 'nonresistant' fraction for Pb contributed about 70.0% to 75.0% and 54.0% of the total Pb concentration in the offshore and intertidal sediments, respectively. As for Cu, the 'nonresistant' fraction contributed about 46.2% to 60.4% and 46.3% of the total Cu concentration in the offshore and intertidal sediments, respectively. The 'nonresistant' fraction contained mostly of anthropogenic metals besides natural origins. These 'nonresistant' percentages indicated that both the offshore and intertidal areas could have received anthropogenic-derived metals, which could be influenced by physico-chemical properties of the sediments. Although the present data indicated that contamination due to Cu and Pb in the west coast of Peninsular Malaysia especially in the

  4. Investigating the zoonotic origin of the West African Ebola epidemic.

    PubMed

    Marí Saéz, Almudena; Weiss, Sabrina; Nowak, Kathrin; Lapeyre, Vincent; Zimmermann, Fee; Düx, Ariane; Kühl, Hjalmar S; Kaba, Moussa; Regnaut, Sebastien; Merkel, Kevin; Sachse, Andreas; Thiesen, Ulla; Villányi, Lili; Boesch, Christophe; Dabrowski, Piotr W; Radonić, Aleksandar; Nitsche, Andreas; Leendertz, Siv Aina J; Petterson, Stefan; Becker, Stephan; Krähling, Verena; Couacy-Hymann, Emmanuel; Akoua-Koffi, Chantal; Weber, Natalie; Schaade, Lars; Fahr, Jakob; Borchert, Matthias; Gogarten, Jan F; Calvignac-Spencer, Sébastien; Leendertz, Fabian H

    2014-12-30

    The severe Ebola virus disease epidemic occurring in West Africa stems from a single zoonotic transmission event to a 2-year-old boy in Meliandou, Guinea. We investigated the zoonotic origins of the epidemic using wildlife surveys, interviews, and molecular analyses of bat and environmental samples. We found no evidence for a concurrent outbreak in larger wildlife. Exposure to fruit bats is common in the region, but the index case may have been infected by playing in a hollow tree housing a colony of insectivorous free-tailed bats (Mops condylurus). Bats in this family have previously been discussed as potential sources for Ebola virus outbreaks, and experimental data have shown that this species can survive experimental infection. These analyses expand the range of possible Ebola virus sources to include insectivorous bats and reiterate the importance of broader sampling efforts for understanding Ebola virus ecology.

  5. Investigating the zoonotic origin of the West African Ebola epidemic

    PubMed Central

    Marí Saéz, Almudena; Weiss, Sabrina; Nowak, Kathrin; Lapeyre, Vincent; Zimmermann, Fee; Düx, Ariane; Kühl, Hjalmar S; Kaba, Moussa; Regnaut, Sebastien; Merkel, Kevin; Sachse, Andreas; Thiesen, Ulla; Villányi, Lili; Boesch, Christophe; Dabrowski, Piotr W; Radonić, Aleksandar; Nitsche, Andreas; Leendertz, Siv Aina J; Petterson, Stefan; Becker, Stephan; Krähling, Verena; Couacy-Hymann, Emmanuel; Akoua-Koffi, Chantal; Weber, Natalie; Schaade, Lars; Fahr, Jakob; Borchert, Matthias; Gogarten, Jan F; Calvignac-Spencer, Sébastien; Leendertz, Fabian H

    2015-01-01

    The severe Ebola virus disease epidemic occurring in West Africa stems from a single zoonotic transmission event to a 2-year-old boy in Meliandou, Guinea. We investigated the zoonotic origins of the epidemic using wildlife surveys, interviews, and molecular analyses of bat and environmental samples. We found no evidence for a concurrent outbreak in larger wildlife. Exposure to fruit bats is common in the region, but the index case may have been infected by playing in a hollow tree housing a colony of insectivorous free-tailed bats (Mops condylurus). Bats in this family have previously been discussed as potential sources for Ebola virus outbreaks, and experimental data have shown that this species can survive experimental infection. These analyses expand the range of possible Ebola virus sources to include insectivorous bats and reiterate the importance of broader sampling efforts for understanding Ebola virus ecology. PMID:25550396

  6. Revisiting the role of global SST anomalies and their effects on West African monsoon variability

    NASA Astrophysics Data System (ADS)

    Pomposi, Catherine; Kushnir, Yochanan; Giannini, Alessandra

    2016-04-01

    The West African Monsoon is a significant component of the global monsoon system, delivering the majority of annual precipitation for the Sahel and varying on timescales from seasons to decades and beyond. Much of the internal variability of this system is driven by sea surface temperature (SST) anomalies and their resulting atmospheric teleconnections linking oceanic changes to land-based precipitation. Previous idealized studies have identified the role of particular ocean basins in driving monsoon variations on a number of key timescales, including the Atlantic basin as the main driver behind decadal-scale changes and the Pacific basin for interannual variability. However, understanding of how the monsoon responds to global SSTs remains incomplete because the system can be affected by moisture availability locally as well as tropical atmospheric stability, both of which are influenced by ocean temperatures. Furthermore, the complexity of how the global ocean basins change in relation to one another (what we refer to as superposition of anomalies) can result in Sahel precipitation anomalies that are contrary to what one might posit when considering the state of a single basin alone (e.g. the 2015 El Niño event and a relatively wet Sahel). The aim of this work is to revisit the role of global SSTs in driving Sahel rainfall variability over the recent past using a blending of observations and new model output. We seek to disentangle the state of various basins in combination with each other in driving normal or anomalously dry or wet years, resolving the ways that remote and local ocean forcings affect the movement of convection from the Guinea coast inland and northward into the Sahel, and include the study of circulation and stability components of the atmosphere. Preliminary diagnostic work suggests that varying SST conditions across ocean basins could imprint distinctly different precipitation responses in the Sahel. For example, precipitation anomalies are

  7. Impact of the Madden Julian Oscillation on the summer West African monsoon in AMIP simulations

    NASA Astrophysics Data System (ADS)

    Niang, Coumba; Mohino, Elsa; Gaye, Amadou T.; Omotosho, J. Bayo

    2016-06-01

    At intraseasonal timescales, convection over West Africa is modulated by the Madden Julian Oscillation (MJO). In this work we investigate the simulation of such relationship by 11 state-of-the-art atmospheric general circulation models runs with prescribed observed sea surface temperatures. In general, the Atmospheric Model Intercomparison Project simulations show good skill in capturing the main characteristics of the summer MJO as well as its influence on convection and rainfall over West Africa. Most models simulate an eastward spatiotemporal propagation of enhanced and suppressed convection similar to the observed MJO, although their signal over West Africa is weaker in some models. In addition, the ensemble average of models' composites gives a better performance in reproducing the main features and timing of the MJO and its impact over West Africa. The influence on rainfall is well captured in both Sahel and Guinea regions thereby adequately producing the transition between positive and negative rainfall anomalies through the different phases as in the observations. Furthermore, the results show that a strong active convection phase is clearly associated with a stronger African Easterly Jet (AEJ) but the weak convective phase is associated with a much weaker AEJ. Our analysis of the equatorial waves suggests that the main impact over West Africa is established by the propagation of low-frequency waves within the MJO and Rossby spectral peaks. Results from the simulations confirm that it may be possible to predict anomalous convection over West Africa with a time lead of 15-20 day.

  8. Milk production of West African Dwarf goats in the Gambia.

    PubMed

    Jaitner, J; Njie, M; Corr, N; Dempfle, L

    2006-04-01

    Goats are important in the low-input systems of West Africa and their main importance lies in their role for income and saving. In addition, it is known that milk offtake for home consumption is also important. In order to obtain information about the real importance of milk offtake, a recording scheme was operated in 27 villages in the Central River Division of The Gambia from July 1998 until January 2000. Detailed information was obtained from about 1500 kiddings. In the recording scheme, any sheep being milked as well as the goats of the International Trypanotolerance Centre nucleus flock were also recorded. In the villages, 36% of all lactations were used for milk offtake, but the fraction milked was lower for the first two lactations. The average length of lactation was 127 days and the average daily milk offtake was 0.18 L. Goats are milked once a day and the residual milk is left for the kids. Milking starts about one week after parturition and stops when the goat becomes pregnant or the kid(s) die or the goat is drying off. The repeatability of the 90-day milk offtake was 0.24 +/- 0.09. Sixty-five percent of goat owner were women and a large fraction of goat owners also owned cattle. Goat milk was used exclusively for home consumption. It is concluded that in breeding and extension work more attention should be given to aspects of milk production.

  9. Outcome of Radioiodine Therapy in a West African Population.

    PubMed

    Onimode, Yetunde A; Ankrah, Alfred; Adedapo, Kayode S

    2016-01-01

    Hyperthyroidism continues to be a pressing public health concern in West Africa. Its prevalence in Africa has been quoted as 1.2%-9.9%, with Graves' disease as its most common cause. Radioiodine-131 (RAI) therapy of hyperthyroidism recently commenced in two government hospitals in Ghana and Nigeria. This is a retrospective analysis of consecutive patients treated with RAI for primary hyperthyroidism at the National Centre for Radiotherapy and Nuclear Medicine (NCRNM) from 2008-2013, and in the University College Hospital (UCH) from 2006-2013. Cure was defined as euthyroidism or hypothyroidism occurring at 6 months post-RAI. Data were analysed using SPSS version 21 and Epi Info version, categorical data were evaluated with the Chi-square test and Fisher's exact test. 94 patients were studied, aged 20-74 years; 78 were females, and 16 were males. 38 were Ghanaian and 56 Nigerian. The presence of thyroid-associated ophthalmopathy (TAO) made cure less likely (χ(2) P = 0.006, odds ratio = 0.118; 95% confidence interval, 0.027-0.518). Other factors assessed proved to be insignificant. Our findings suggest that hyperthyroid patients with TAO will benefit from a higher RAI dose than their counterparts without TAO. PMID:26912975

  10. Leading and Trailing Anvil Clouds of West African Squall Lines

    NASA Technical Reports Server (NTRS)

    Centrone, Jasmine; Houze, Robert A.

    2011-01-01

    The anvil clouds of tropical squall-line systems over West Africa have been examined using cloud radar data and divided into those that appear ahead of the leading convective line and those on the trailing side of the system. The leading anvils are generally higher in altitude than the trailing anvil, likely because the hydrometeors in the leading anvil are directly connected to the convective updraft, while the trailing anvil generally extends out of the lower-topped stratiform precipitation region. When the anvils are subdivided into thick, medium, and thin portions, the thick leading anvil is seen to have systematically higher reflectivity than the thick trailing anvil, suggesting that the leading anvil contains numerous larger ice particles owing to its direct connection to the convective region. As the leading anvil ages and thins, it retains its top. The leading anvil appears to add hydrometeors at the highest altitudes, while the trailing anvil is able to moisten a deep layer of the atmosphere.

  11. Bayesian species delimitation in West African forest geckos (Hemidactylus fasciatus)

    PubMed Central

    Leaché, Adam D.; Fujita, Matthew K.

    2010-01-01

    Genealogical data are an important source of evidence for delimiting species, yet few statistical methods are available for calculating the probabilities associated with different species delimitations. Bayesian species delimitation uses reversible-jump Markov chain Monte Carlo (rjMCMC) in conjunction with a user-specified guide tree to estimate the posterior distribution for species delimitation models containing different numbers of species. We apply Bayesian species delimitation to investigate the speciation history of forest geckos (Hemidactylus fasciatus) from tropical West Africa using five nuclear loci (and mtDNA) for 51 specimens representing 10 populations. We find that species diversity in H. fasciatus is currently underestimated, and describe three new species to reflect the most conservative estimate for the number of species in this complex. We examine the impact of the guide tree, and the prior distributions on ancestral population sizes (θ) and root age (τ0), on the posterior probabilities for species delimitation. Mis-specification of the guide tree or the prior distribution for θ can result in strong support for models containing more species. We describe a new statistic for summarizing the posterior distribution of species delimitation models, called speciation probabilities, which summarize the posterior support for each speciation event on the starting guide tree. PMID:20519219

  12. Regional Climate Modeling of West African Summer Monsoon Climate: Impact of Historical Boundary Forcing

    NASA Astrophysics Data System (ADS)

    Kebe, I.

    2015-12-01

    In this paper, we analyze and intercompare the performance of an ensemble of three Regional Climate Models (RCMs) driven by three set of Global Climate Models (GCMs), in reproducing seasonal mean climatologies with their annual cycle and the key features of West African summer monsoon over 20 years period (1985-2004) during the present day. The results show that errors in lateral boundary conditions from the GCM members, have an unexpected way on the skill of the RCMs in reproducing regional climate features such as the West African Monsoon features and the annual cycle of precipitation and temperature in terms of outperforming the GCM simulation. It also shows the occurrence of the West African Monsoon jump, the intensification and northward shift of the Saharan Heat Low (SHL) as expressed in some RCMs than the GCMs. Most RCMs also capture the mean annual cycle of precipitation and temperature, including, single and double-peaked during the summer months, in terms of events and amplitude. In a series of RCMs and GCMs experiments between the Sahara region and equatorial Africa, the presence of strong positive meridional temperature gradients at the surface and a strong meridional gradients in the potential temperatures near the surface are obvious, indicating the region of strong vertical shear development enough to establish easterly flow such as the African easterly jet. In addition, the isentropic potential vorticity (IPV) gradient decreases northward in the lower troposphere across northern Africa, with the maximum reversal on the 315-K surface. The region with negative IPV gradient favors the potential instability which has been associated with the growth of easterly waves.

  13. The habitat of petroleum in the Brazilian marginal and west African basins: A biological marker investigation

    SciTech Connect

    Mello, M.R.; Soldan, A.L. ); Maxwell, J.R. ); Figueira, J. )

    1990-05-01

    A geochemical and biological marker investigation of a variety of oils from offshore Brazil and west Africa, ranging in age from Lower Cretaceous to Tertiary, has been done, with the following aims: (1) assessing the depositional environment of source rocks, (2) correlating the reservoired oils, (3) comparing the Brazilian oils with their west African counterparts. The approach was based in stable isotope data; bulk, elemental, and hydrous pyrolysis results; and molecular studies involving quantitative geological marker investigations of alkanes using GC-MS and GC-MS-MS. The results reveal similarities between groups of oils from each side of the Atlantic and suggest an origin from source rocks deposited in five types of depositional environment: lacustrine fresh water, lacustrine saline water, marine evaporitic/carbonate, restricted marine anoxic, and marine deltaic. In west Africa, the Upper Cretaceous marine anoxic succession (Cenomanian-Santonian) appears to be a major oil producer, but in Brazil it is generally immature. The Brazilian offshore oils have arisen mainly from the pre-salt sequence, whereas the African oils show a balance between origins from the pre-salt and marine sequences. The integration of the geochemical and geological data indicate that new frontiers of hydrocarbon exploration in the west African basins must consider the Tertiary reservoirs in the offshore area of Niger Delta, the reservoirs of the rift sequences in the shallow-water areas of south Gabon, Congo, and Cuanza basins, and the reservoirs from the drift sequences (post-salt) in the deep-water areas of Gabon, Congo Cabinda, and Cuanza basins.

  14. Five centuries of U.S. West Coast drought: Occurrence, spatial distribution, and associated atmospheric circulation patterns

    NASA Astrophysics Data System (ADS)

    Wise, Erika K.

    2016-05-01

    The U.S. West Coast drought commencing in 2012 developed in association with a large, persistent high-pressure ridge linked to internal atmospheric variability. This study places the occurrence, spatial patterns, and associated circulation features of West Coast drought into a paleoclimate context through a synoptic dendroclimatology approach linking atmospheric circulation to surface hydroclimate patterns. Spatial reconstructions of upper atmosphere pressure patterns and cool-season drought show that West Coast-wide drought, although relatively rare compared to north-south dipole drought, has occurred periodically since 1500 Common Era and is consistently associated with a strong ridge centered along the Pacific Northwest coast. Atmospheric blocking is also linked to north-dry dipole droughts, while south-dry and wider Western droughts indicate La Niña-type patterns. The transition latitude between the northern and southern sides of the western precipitation dipole, important for California hydroclimate patterns, has had frequent year-to-year fluctuations but remained centered on 40°N over the past five centuries.

  15. Seasonality of the plankton community at an east and west coast monitoring site in Scottish waters

    NASA Astrophysics Data System (ADS)

    Bresnan, Eileen; Cook, Kathryn B.; Hughes, Sarah L.; Hay, Steve J.; Smith, Kerry; Walsham, Pamela; Webster, Lynda

    2015-11-01

    This study presents the first comparative description of the physics, nutrients and plankton communities at two Scottish monitoring sites between 2003 and 2012; Stonehaven on the east coast of Scotland and Loch Ewe on the west coast. This description provides baseline information about the diversity of the plankton community in Scottish waters to support assessment of the plankton community for the EU Marine Strategy Framework Directive. Spring time temperatures at Loch Ewe were approximately 2 °C higher and the median secchi depth was almost 1 m greater than at Stonehaven during this period. Freshwater inflow from the river Ewe may promote water column stability at Loch Ewe. These factors may account for the earlier spring bloom observed at the Loch Ewe monitoring site. The seasonality of chlorophyll 'a' at Loch Ewe was typical of stratified waters in temperate regions with a strong spring/autumn peak attributed to increased numbers of diatoms whilst dinoflagellates dominated during the summer. At Stonehaven highest concentrations of chlorophyll were recorded between May and June and the autumn diatom bloom was considerably less than in Loch Ewe. A higher biomass of zooplankton grazers was found at Loch Ewe than at Stonehaven. Pseudocalanus was the dominant copepod at both sites, particularly during the spring period. Zooplankton carnivores were also more abundant at Loch Ewe than at Stonehaven and were dominated by cnidarians. Considerable interannual variability was observed in cnidarian abundance and diversity at both sites. Variation in the abundance of Ceratium, Calanus finmarchicus and Calanus helgolandicus at both sites followed similar trends in other time series suggesting that the plankton communities at Stonehaven and Loch Ewe are responding to large scale environmental influences.

  16. Reported traumatic injuries among West Coast Dungeness crab fishermen, 2002–2014

    PubMed Central

    Case, Samantha; Bovbjerg, Viktor; Lucas, Devin; Syron, Laura; Kincl, Laurel

    2015-01-01

    Background Commercial fishing is a high-risk occupation. The West Coast Dungeness crab fishery has a high fatality rate; however, nonfatal injuries have not been previously studied. The purpose of this report was to describe the characteristics of fatal and nonfatal traumatic occupational injuries and associated hazards in this fleet during 2002–2014. Materials and methods Data on fatal injuries were obtained from a surveillance system managed by the National Institute for Occupational Safety and Health. Data on nonfatal injuries were manually abstracted from Coast Guard investigation reports and entered into a study database. Descriptive statistics were used to characterise demographics, injury characteristics, and work processes performed. Results Twenty-eight fatal and 45 nonfatal injuries were reported between 2002 and 2014 in the Dungeness crab fleet. Most fatalities were due to vessel disasters, and many nonfatal injuries occurred on-deck when fishermen were working with gear, particularly when hauling the gear (47%). The most frequently reported injuries affected the upper extremities (48%), and fractures were the most commonly reported injury type (40%). The overall fatality rate during this time period was 209 per 100,000 full-time equivalent workers and the rate of nonfatal injury was 3.4 per 1,000 full-time equivalent workers. Conclusions Dungeness crab fishermen are at relatively high risk for fatal injuries. Nonfatal injuries were limited to reported information, which hampers efforts to accurately estimate nonfatal injury risk and understand fishing hazards. Further research is needed to identify work tasks and other hazards that cause nonfatal injuries in this fleet. Engaging fishermen directly may help develop approaches for injury prevention. PMID:26726891

  17. The morphology and migration of transverse bars off the west-central Florida coast

    USGS Publications Warehouse

    Gelfenbaum, G.; Brooks, G.R.

    2003-01-01

    A series of migrating shore-normal sandbars with wavelengths of 75-120 m and heights up to 2 m have been identified off the northern tip of Anna Maria Island, a barrier island on the west-central Florida coast. Similar features have been described elsewhere since the 1930s and termed 'transverse bars'. The transverse bars identified off Anna Maria Island are found for about 3 km along the coast and extend 4 km offshore, well outside the normal surf-zone width. No cusps or any other associated beach expression is evident despite the fact that the bars come to within about 75 m of the beach. Sediments on the crests of the bars are a well-sorted fine quartz sand, whereas sediments in the troughs are a poorly sorted coarse carbonate shell hash. Historical aerial photographs and repeated high-resolution bathymetric surveys provide a means of quantifying the migration of the transverse bars. Analyses of orthorectified aerial photographs from the early 1940s through the mid 1990s clearly show movement or migration taking place in the bar field. In the 40-yr period from 1951 to 1991, the southern edge of the bar field moved 200-350 m to the south, with an average long-term migration rate of 8 m/yr. Repeated bathymetric surveys over an 8-month period give an average short-term migration rate of 21 m/yr to the south. Wave and current measurements suggest that southerly winds associated with the passage of cold fronts drive near-bed currents to the south that are strong enough to initiate sediment transport and cause the southerly migration of the transverse bars.

  18. On the stationarity of Floods in west African rivers

    NASA Astrophysics Data System (ADS)

    NKA, B. N.; Oudin, L.; Karambiri, H.; Ribstein, P.; Paturel, J. E.

    2014-12-01

    West Africa undergoes a big change since the years 1970-1990, characterized by very low precipitation amounts, leading to low stream flows in river basins, except in the Sahelian region where the impact of human activities where pointed out to justify the substantial increase of floods in some catchments. More recently, studies showed an increase in the frequency of intense rainfall events, and according to observations made over the region, increase of flood events is also noticeable during the rainy season. Therefore, the assumption of stationarity on flood events is questionable and the reliability of flood evolution and climatic patterns is justified. In this work, we analyzed the trends of floods events for several catchments in the Sahelian and Sudanian regions of Burkina Faso. We used thirteen tributaries of large river basins (Niger, Nakambe, Mouhoun, Comoé) for which daily rainfall and flow data were collected from national hydrological and meteorological services of the country. We used Mann-Kendall and Pettitt tests to detect trends and break points in the annual time series of 8 rainfall indices and the annual maximum discharge records. We compare the trends of precipitation indices and flood size records to analyze the possible causality link between floods size and rainfall pattern. We also analyze the stationary of the frequency of flood exceeding the ten year return period level. The samples were extracted by a Peak over threshold method and the quantification of change in flood frequency was assessed by using a test developed by Lang M. (1995). The results exhibit two principal behaviors. Generally speaking, no trend is detected on catchments annual maximum discharge, but positive break points are pointed out in a group of three right bank tributaries of the Niger river that are located in the sahelian region between 300mm to 650mm. These same catchments show as well an increase of the yearly number of flood greater than the ten year flood since

  19. Analysis and Prediction of West African Moist Events during the Boreal Spring of 2009

    NASA Astrophysics Data System (ADS)

    Mera, Roberto Javier

    Weather and climate in Sahelian West Africa are dominated by two major wind systems, the southwesterly West African Monsoon (WAM) and the northeasterly (Harmattan) trade winds. In addition to the agricultural benefit of the WAM, the public health sector is affected given the relationship between the onset of moisture and end of meningitis outbreaks. Knowledge and prediction of moisture distribution during the boreal spring is vital to the mitigation of meningitis by providing guidance for vaccine dissemination. The goal of the present study is to (a) develop a climatology and conceptual model of the moisture regime during the boreal spring, (b) investigate the role of extra-tropical and Convectively-coupled Equatorial Waves (CCEWs) on the modulation of westward moving synoptic waves and (c) determine the efficacy of a regional model as a tool for predicting moisture variability. Medical reports during 2009, along with continuous meteorological observations at Kano, Nigeria, showed that the advent of high humidity correlated with cessation of the disease. Further analysis of the 2009 boreal spring elucidated the presence of short-term moist events that modulated surface moisture on temporal scales relevant to the health sector. The May moist event (MME) provided insight into interplays among climate anomalies, extra-tropical systems, equatorially trapped waves and westward-propagating synoptic disturbances. The synoptic disturbance initiated 7 May and traveled westward to the coast by 12 May. There was a marked, semi-stationary moist anomaly in the precipitable water field (kg m-2) east of 10°E through late April and early May, that moved westward at the time of the MME. Further inspection revealed a mid-latitude system may have played a role in increasing the latitudinal amplitude of the MME. CCEWs were also found to have an impact on the MME. A coherent Kelvin wave propagated through the region, providing increased monsoonal flow and heightened convection. A

  20. The puzzle of high heads beneath the West Cumbrian coast, UK: a possible solution

    NASA Astrophysics Data System (ADS)

    Black, John H.; Barker, John A.

    2016-03-01

    A region of high heads within the Borrowdale Volcanic Group (BVG; a fractured crystalline rock) beneath the coastal plain of West Cumbria, England (UK), is identified as a possible relic left over by the Late Devensian ice sheet. It was found during investigations in the 1990s. Contemporary modelling work failed to produce a satisfactory explanation of the high heads compatible with the `cold recharge' isotopic signature of the groundwater. This study has reassessed the original hydraulic testing results. By plotting density-adjusted heads versus their depth below the water table in the immediate vicinity of the borehole in which they were measured, a depth profile resembling a `wave' was revealed with a peak value located at 1,100 m depth. The possibility that this wave represents relic heads from the last major ice sheet has been assessed using one-dimensional mathematical analysis based on a poroelastic approach. It is found that a wet-based ice sheet above the West Cumbrian coast was probably thick enough and sufficiently long-lasting to leave such relic heads providing that the hydraulic diffusivity of the BVG is in the order of 10-6 m s-1. Initial assessment 20 years ago of the long-interval slug tests suggested that such low values are not likely. More recent interpretation argues for such low values of hydraulic diffusivity. It is concluded that ice sheet recharge is the most likely cause of the raised heads, that the BVG contains significant patches of very low conductivity rock, and that long-interval single-hole tests should be avoided in fractured crystalline rock.

  1. Identification of naturally occurring hybrids between two overexploited sciaenid species along the South African coast.

    PubMed

    Mirimin, L; Kerwath, S E; Macey, B M; Bester-van der Merwe, A E; Lamberth, S J; Bloomer, P; Roodt-Wilding, R

    2014-07-01

    Hybridisation between fish species can play a significant role in evolutionary processes and can influence management and conservation planning, however, this phenomenon has been widely understudied, especially in marine organisms. The distribution limits of two sciaenid species (silver kob, Argyrosomus inodorus, and dusky kob, A. japonicus) partly overlap along the South African coast, where both species have undergone severe depletion due to overfishing. Following the identification of a number of possible cases of species misidentification or hybridisation (21 out of 422 individuals), nuclear and mitochondrial DNA data (12microsatellite loci and 562bp of the COI gene) were analysed to investigate the genetic composition of these individuals. Results indicated a field-based species misidentification rate of approximately 2.8% and a rate of natural hybridisation of 0.7%. Interestingly, all hybrid fish resulted from first-generation (F1) hybridisation events, which occurred exclusively between silver kob females and dusky kob males. Whether hybridisation is the result of natural events (such as secondary contact following a shift in distribution range), or anthropogenic activities (size-selective pressure due to overfishing), these findings have important implications for critical recovery and future management of these species in the wild. PMID:24582737

  2. Identification of naturally occurring hybrids between two overexploited sciaenid species along the South African coast.

    PubMed

    Mirimin, L; Kerwath, S E; Macey, B M; Bester-van der Merwe, A E; Lamberth, S J; Bloomer, P; Roodt-Wilding, R

    2014-07-01

    Hybridisation between fish species can play a significant role in evolutionary processes and can influence management and conservation planning, however, this phenomenon has been widely understudied, especially in marine organisms. The distribution limits of two sciaenid species (silver kob, Argyrosomus inodorus, and dusky kob, A. japonicus) partly overlap along the South African coast, where both species have undergone severe depletion due to overfishing. Following the identification of a number of possible cases of species misidentification or hybridisation (21 out of 422 individuals), nuclear and mitochondrial DNA data (12microsatellite loci and 562bp of the COI gene) were analysed to investigate the genetic composition of these individuals. Results indicated a field-based species misidentification rate of approximately 2.8% and a rate of natural hybridisation of 0.7%. Interestingly, all hybrid fish resulted from first-generation (F1) hybridisation events, which occurred exclusively between silver kob females and dusky kob males. Whether hybridisation is the result of natural events (such as secondary contact following a shift in distribution range), or anthropogenic activities (size-selective pressure due to overfishing), these findings have important implications for critical recovery and future management of these species in the wild.

  3. Dry intrusions in the West African monsoon mid-troposphere during the AMMA experiment

    NASA Astrophysics Data System (ADS)

    Deme, A.; Roca, R.

    2009-04-01

    Mid-troposphere dry air patches (RH < 10%) have been recently detected over the African monsoon region and in particular over Sahel. At 500 hPa, these dry air features are thought to play a complex role onto convection: inhibition isolated convective cells but favouring already organized convection by feeding rear-inflow currents with dry air. The inhibiting action of the dry air onto convection comes from the temperature inversion induced by radiation at the bottom of the dry layer and/or by entrainment of dry air in ascending parcel that decreases its buoyancy. The organizing effect is associated to mesoscale currents within and around long lasting squall lines. This mid-tropospheric dry air has been shown to originate from the mid-latitudes upper level jets, therefore coined extra-tropical dry intrusions.Among all the forcings that control the dynamics of the West African monsoon, the role of a dry mid-troposphere needs to be clarified. The present study is dedicated to this objective and it is focused on extra-tropical dry air intrusions in the West African mid-troposphere during the AMMA campaign. The low level dynamics is documented (African Easterly Jet, African Easterly Wave) thanks to the NCEP operational analysis. It is completed by the radiosondes especially for the temperature and water vapor distribution. Back-trajectory are computed in order to highlight the origin of the tropospheric air mass. Finally Meteosat Second Generation derived water vapor and cloud and rainfall parameters are used to characterize the convective activity and its moist environment. Dry intrusions in the African mid troposphere during the summer 2006 have been shown to be associated with two major modes of occurrences: a 40-50 days mode and a 10-20 days mode. The long mode exhibits negative anomaly of the rainfall and a very large scale structure covering the whole West Africa region when occurring while the short mode is more restricted to the Sahelian longitude. Similarly

  4. Association studies in QTL regions linked to bovine trypanotolerance in a West African crossbred population.

    PubMed

    Dayo, G K; Gautier, M; Berthier, D; Poivey, J P; Sidibe, I; Bengaly, Z; Eggen, A; Boichard, D; Thevenon, S

    2012-04-01

    African animal trypanosomosis is a parasitic blood disease transmitted by tsetse flies and is widespread in sub-Saharan Africa. West African taurine breeds have the ability, known as trypanotolerance, to limit parasitaemia and anaemia and remain productive in enzootic areas. Several quantitative trait loci (QTL) underlying traits related to trypanotolerance have been identified in an experimentally infected F(2) population resulting from a cross between taurine and zebu cattle. Although this information is highly valuable, the QTL remain to be confirmed in populations subjected to natural conditions of infection, and the corresponding regions need to be refined. In our study, 360 West African cattle were phenotyped for the packed cell volume control under natural conditions of infection in south-western Burkina Faso. Phenotypes were assessed by analysing data from previous cattle monitored over 2 years in an area enzootic for trypanosomosis. We further genotyped for 64 microsatellite markers mapping within four previously reported QTL on BTA02, BTA04, BTA07 and BTA13. These data enabled us to estimate the heritability of the phenotype using the kinship matrix between individuals computed from genotyping data. Thus, depending on the estimators considered and the method used, the heritability of anaemia control ranged from 0.09 to 0.22. Finally, an analysis of association identified an allele of the MNB42 marker on BTA04 as being strongly associated with anaemia control, and a candidate gene, INHBA, as being close to that marker. PMID:22404348

  5. The Genetic Contribution of West-African Ancestry to Protection against Central Obesity in African-American Men but Not Women: Results from the ARIC and MESA Studies

    PubMed Central

    Klimentidis, Yann C.; Arora, Amit; Zhou, Jin; Kittles, Rick; Allison, David B.

    2016-01-01

    Over 80% of African-American (AA) women are overweight or obese. A large racial disparity between AA and European-Americans (EA) in obesity rates exists among women, but curiously not among men. Although socio-economic and/or cultural factors may partly account for this race-by-sex interaction, the potential involvement of genetic factors has not yet been investigated. Among 2814 self-identified AA in the Atherosclerosis Risk in Communities study, we estimated each individual's degree of West-African genetic ancestry using 3437 ancestry informative markers. We then tested whether sex modifies the association between West-African genetic ancestry and body mass index (BMI), waist-circumference (WC), and waist-to-hip ratio (WHR), adjusting for income and education levels, and examined associations of ancestry with the phenotypes separately in males and females. We replicated our findings in the Multi-Ethnic Study of Atherosclerosis (n = 1611 AA). In both studies, we find that West-African ancestry is negatively associated with obesity, especially central obesity, among AA men, but not among AA women (pinteraction = 4.14 × 10−5 in pooled analysis of WHR). In conclusion, our results suggest that the combination of male gender and West-African genetic ancestry is associated with protection against central adiposity, and suggest that the large racial disparity that exists among women, but not men, may be at least partly attributed to genetic factors. PMID:27313598

  6. A whole genome Bayesian scan for adaptive genetic divergence in West African cattle

    PubMed Central

    2009-01-01

    Background The recent settlement of cattle in West Africa after several waves of migration from remote centres of domestication has imposed dramatic changes in their environmental conditions, in particular through exposure to new pathogens. West African cattle populations thus represent an appealing model to unravel the genome response to adaptation to tropical conditions. The purpose of this study was to identify footprints of adaptive selection at the whole genome level in a newly collected data set comprising 36,320 SNPs genotyped in 9 West African cattle populations. Results After a detailed analysis of population structure, we performed a scan for SNP differentiation via a previously proposed Bayesian procedure including extensions to improve the detection of loci under selection. Based on these results we identified 53 genomic regions and 42 strong candidate genes. Their physiological functions were mainly related to immune response (MHC region which was found under strong balancing selection, CD79A, CXCR4, DLK1, RFX3, SEMA4A, TICAM1 and TRIM21), nervous system (NEUROD6, OLFM2, MAGI1, SEMA4A and HTR4) and skin and hair properties (EDNRB, TRSP1 and KRTAP8-1). Conclusion The main possible underlying selective pressures may be related to climatic conditions but also to the host response to pathogens such as Trypanosoma(sp). Overall, these results might open the way towards the identification of important variants involved in adaptation to tropical conditions and in particular to resistance to tropical infectious diseases. PMID:19930592

  7. Rain- vapour isotopic interaction over the south-west coast of India

    NASA Astrophysics Data System (ADS)

    Palliyil Ravisankar, Lekshmy; Madhavan, Midhun; Rengaswamy, Ramesh

    2015-04-01

    Boundary layer water vapor isotopic composition (δv) is an important factor that controls the isotopic composition of evaporation flux and modulating the δ18O of tree ring cellulose through plant physiological cycle. But due to the difficult sampling procedure for water vapor, δv has rarely been quantified. Since many simple isotopic models require δvas an input, mostly we assume that the water vapor is in isotopic equilibrium with δof monthly rain (δr). Here we present simultaneous observations of water vapour (~ 300 samples) and rainfall (~200 samples) isotopic ratios from two stations in the south-west coast of India (both the stations are located in the west of Western Ghats), sampled during April- October, 2012. Daily rain water and water vapour (cryogenic trapping method) were collected according to the IAEA protocol and the isotopic analyses (D and 18O) were done using a Thermo Fisher Delta V+ Isotope Ratio Mass Spectrometer. We observe that, water vapour and rain are close to the equilibrium values during pre monsoon (April-May, ɛ = δr - δv= 8.9 ± 1.4 ), summer monsoon (June-September, ɛ = 9.0 ± 1.8 ) and North- East (NE) monsoon (October, ɛ = 7.9 ± 2.9 ) seasons. However, some individual rain events show more deviations from the equilibrium values. NE monsoon rainfall and water vapour are isotopically more depleted in 18O compared to the pre monsoon and summer monsoon seasons, in which the depletion is more in rain (~4 ) compared to water vapour (~2 ). This is because of the 18O enrichment of ground level vapour due to local evapo- transpiration (stations are at the leeward side of the Ghats), while rainfall is directly formed from the NE monsoon clouds which is more depleted in 18O. These results will be useful for the interpretation of δ18O of tree rings from south west.

  8. Airborne mercury pollution from a large oil spill accident on the west coast of Korea.

    PubMed

    Pandey, Sudhir Kumar; Kim, Ki-Hyun; Yim, Un-Hyuk; Jung, Myung-Chae; Kang, Chang-Hee

    2009-05-15

    Atmospheric mercury pollution was recognized after a large oil spill on the west coast of Korea on 7 December 2007. In this study, the concentrations of gaseous elemental mercury (GEM: Hg(0)) in air were measured both shortly after the oil spill ( approximately 100h) and 1month after the accident near the accident site. When the Hg concentration levels were compared between two seashore sites and two parallel sites offshore, the values tend to decrease further offshore. The unusual rise in Hg concentration levels observed on the seashore area shortly after the accident (mean of 16.4+/-9.85ngm(-3)) dropped dramatically after 1month with active cleanup activities (2.99+/-1.40ngm(-3)). Because of the connection between crude oil and Hg (one of the major impurities), the unusual rise in the atmospheric Hg after the oil spill can be explained by the active evasion of Hg from the spilled crude oil. Although Hg levels determined a few days after the accident did not exceed the reference exposure limits (REL) proposed by several agencies, the early build-up of elemental mercury level due to the oil spill might have exerted certain impacts on the surrounding environments.

  9. Seasonal biomass and energy content in seagrass communities on the west coast of Florida

    SciTech Connect

    Dawes, C.J.; Hall, M.O.; Riechert, R.K.

    1985-01-01

    Seasonal collections were made over a 16 month period in seven seagrass communities on the west coast of Florida. The seagrass component accounted for at least 45% of the total biomass and Thalassia testudinum was the dominant species. The 15 month mean of total biomass at six sites that were dominated year around by T. testudinum from Tampa Bay to Cedar Key, Florida was 385 g dry weight m/sup 2/ or 1.42 tons dry weight/acre. The drift and attached seaweed components showed seasonal fluctuations in terms of species and biomass. Of the six open water sites, only one site, characterized by depressed salinity, showed significant differences in seasonal biomass for T. testudinum using a nested ANOVA and Student-Newman-Keul's test for variance. Available kilocalories ranged from a 16 month low of 344 to a high of 1837 kcal/m/sup 2/ with the highest biomass and caloric values occurring in the late spring and summer.

  10. Upwelling along the Swedish west coast during the 20th century

    NASA Astrophysics Data System (ADS)

    Björk, Göran; Nordberg, Kjell

    2003-07-01

    A time series of geostrophic winds from 1892 until present is used to force a simple upwelling model. The model is tuned against a long time series (1930-1989) of daily hydrographic observations at Bornö station inside Gullmar fjord at the Swedish west coast. It is shown that a large part of the short-term variability at Bornö is controlled by upwelling events that can be predicted from the model. Statistical properties of upwelling events for the entire forcing period are presented as well as time series of upwelling and downwelling. Distinctive feature of the upwelling in the time series are: a declining trend between the late 1890s and 1920, an increasing trend between 1920 and 1940s and another declining trend between 1950s and 1990. After 1990 no trend is obvious. Another feature is that upwelling during summer (May-September) is much less intense after 1963. The up/downwelling is related in a qualitative way to the North Atlantic oscillation index during January-April but there is no correlation during summer. Some possible effects on the coastal marine environment due to long-term changes of the upwelling intensity are discussed.

  11. Velocities of Thwaites Glacier and smaller glaciers along the Marie Byrd Land coast, West Antarctica

    USGS Publications Warehouse

    Rosanova, C.E.; Lucchitta, B.K.; Ferrigno, J.G.

    1998-01-01

    Average velocities for time intervals ranging from <1 to 15 years were measured by tracking ice-surface patterns on sequential Landsat and European Remote-sensing Satellite synthetic aperture radar images. Velocities of Thwaites Glacier range from 2.2 km a-1 above the grounding line to 3.4 km a-1 at the limit of measurements on Thwaites Glacier ice tongue. The glacier increases in velocity by about 1 km a-1 where it crosses the grounding line. Over the period 1984-93, Thwaites Glacier ice tongue accelerated by about 0.6 km a-1. Velocities of the floating part of several minor glaciers and some ice shelves are also determined: Land Glacier, 1.7-1.9 km a-1; DeVicq Glacier, 0.7-1.1 km a-1; Dotson Ice Shelf, 0.2-0.5 km a-1; Getz Ice Shelf, 0.2-0.8 km a-1; and Sulzberger Ice Shelf, 0.01-0.02 km a-1. The high velocities along the Marie Byrd Land coast are consistent with the high precipitation rates over West Antarctica and, for some of the glaciers, the lack of buttressing ice shelves.

  12. Food intake of young cod and flounder in a shallow bay on the Swedish west coast

    NASA Astrophysics Data System (ADS)

    Pihl, L.

    The importance of shallow soft bottom areas as nursery grounds for I-ground cod, Gadus morhua, and I- to IV-group flounder, Platichthys flesus, was investigated in a 20 000 m 2 bay, 0 to 1 m deep, on the Swedish west coast. To estimate the amount of visiting fish and their food intake the bay was enclosed with a net once a month from July to November 1979 and from April to November 1980. At each occasion about 60 cods and 8 to 50 flounders were caught. The total biomass of the cod and flounder was 1 to 14 kg and 2 to 13 kg wet weight, respectively. The cod preyed on mobile epifauna such as Carcinus maenas, Crangon crangon and Pomatoschistus spp., whereas the flounder was eating infauna mainly Mya arenaria, Cardium spp. and Nereis spp. The food intake within the area was calculated to approximate 35 and 10 kg wet weight from April to November for cod and flounder, respectively.

  13. Diatom community dynamics in a tropical, monsoon-influenced environment: West coast of India

    NASA Astrophysics Data System (ADS)

    D'Costa, Priya M.; Anil, Arga Chandrashekar

    2010-07-01

    Diatom communities are influenced by environmental perturbations, such as the monsoon system that impact the niche opportunities of species. To discern the influence of the monsoon system on diatom community structure, we sampled during two consecutive post-monsoons (2001 and 2002) and the intervening pre-monsoon at Mumbai and Jawaharlal Nehru ports along the central west coast of India. Characteristic temporal shifts in diatom community structure were observed across the sampling periods; these were mainly driven by temperature, salinity and dissolved oxygen saturation. The nutrient-poor pre-monsoon period supported low abundance yet high species richness and diversity of diatoms. Coscinodiscus, Cyclotella, Thalassiosira, Triceratium, Pleurosigma, Skeletonema and Surirella were the most dominant genera. Both the post-monsoon periods, following dissimilar monsoon events, were dominated by Skeletonema costatum, but differed in some of the residual species . Thalassiosira and Thalassionema spp. dominated mostly during post-monsoon I whereas Triceratium and Pleurosigma spp. dominated during post-monsoon II. To understand the underlying ecological mechanisms involved in such dynamics, we focus on the dominant diatom species in post-monsoon periods, S. costatum, that contributes up to 60% to total diatom cell numbers. This research is relevant in light of the fluctuating monsoon regimes over the Asian continent, the confounding effects of anthropogenic eutrophication and the resulting cascading effects on trophic web dynamics.

  14. Bioaccumulation characteristics of perfluoroalkyl acids (PFAAs) in coastal organisms from the west coast of South Korea.

    PubMed

    Hong, Seongjin; Khim, Jong Seong; Wang, Tieyu; Naile, Jonathan E; Park, Jinsoon; Kwon, Bong-Oh; Song, Sung Joon; Ryu, Jongseong; Codling, Garry; Jones, Paul D; Lu, Yonglong; Giesy, John P

    2015-06-01

    Year-round monitoring for perfluoroalkyl acids (PFAAs) along the west coast of South Korea targeting long-term changes in water and coastal organisms has been conducted since 2008. In this study, we present the most recent 5-years of accumulated data and scrutinize the relationship between concentrations in water and biota highlighting bioaccumulation characteristics. Twelve individual PFAAs in samples of water (n=43) and biota (n=59) were quantified by use of HPLC-MS/MS after solid phase extraction. In recent years, concentrations of PFAAs in water have been generally decreasing, but profiles of relative concentrations of individual PFAAs vary among location and year. Bioaccumulation of PFAAs in various organisms including fishes, bivalves, crabs, gastropods, shrimps, starfish, and polychaetes varied among species. However, overall bioaccumulation of PFAAs was dependent on corresponding concentrations of PFAAs in water within an area. In organ-specific distributions of PFAAs, greater concentrations of PFAAs were found in intestine of fish (green eel goby). This result suggests that PFAAs are mainly accumulated via dietary exposure, while greater concentrations were found in gill and intestine of bivalve (oyster) which suggests both waterborne and dietary exposures to these organisms. Concentrations of PFAAs in biota did not decrease over time (2008-2010), indicating that continuing bioaccumulation followed by slow degradation or excretion of PFAAs accumulated in biota. Overall, spatio-temporal distributions of PFAAs in water and bioaccumulation characteristics seemed to be associated with recent restrictions of PFOS-based products and uses of PFBS-based substitutes.

  15. On the relationship between sea surface temperatures, circulation parameters and temperatures over west coast of India.

    PubMed

    Revadekar, J V; Varikoden, Hamza; Murumkar, P K; Ahmed, S A

    2016-05-01

    The oceans and the atmosphere are tightly linked and they together form the most dynamic component of the climate system. Topography and proximity to the surrounding seas of the region determine the temperature of the area. West Coast (WC) of India is a high elevated region surrounded by large oceanic area, therefore, an attempt is made in this study to examine the trends and variability in temperature over WC in relation to oceanic phenomena. Temperature over the WC shows considerable year-to-year variation with anomalous cool years in recent warm epoch. Therefore, sea surface temperature (SST) and associated winds have been analyzed to understand possible mechanism behind the variation in temperatures over the WC. During the winter, north-easterlies prevail over the WC which blows from land to ocean. Variations in SSTs alter the strength of these winds to cause anomalies in temperature over the WC. Indian Ocean Dipole (IOD) appears to have a dominant role in climate of the WC, whereas SSTs over the equatorial Pacific do not show any impact on temperatures over the WC. Study indicates that the strengthening of north-easterlies due to negative phase of Indian Ocean Dipole causes cooling over the WC of India. PMID:26874773

  16. Magnitude scaling relationship from the first P-wave arrivals on Canada's west coast

    NASA Astrophysics Data System (ADS)

    Eshaghi, A.; Tiampo, K. F.

    2011-12-01

    The empirical magnitude scaling relationship from ground-motion period parameter τc is derived using vertical waveforms recorded in the Cascadia Subduction Zone (CSZ) along Canada's west coast. A high-pass filtered displacement amplitude parameter, Pd, is calculated from the initial 3 s of the P waveforms and the empirical relationship between Pd and peak ground velocity, PGV, is derived using the same data set. We selected earthquakes of M >3.0 recorded during 1996-2009 by the seismic network stations in the region operated by National Resources Canada (NRCan). In total, 90 events were selected and the vertical components of the earthquakes signals were converted to ground velocity and displacement. The displacements were filtered with a one-way Butterworth high-pass filter with a cut-off frequency of 0.075 Hz. Pd and τc are computed from the vertical seismogram components. While the average magnitude error was approximately 0.70 magnitude units when using the individual record, the error dropped to approximately 0.5 magnitude units when using the average τc for each event. In case of PGV, the average error is approximately 0.3. These relationships may be used for initial steps in establishing an earthquake early warning system for the CSZ.

  17. Taxonomic diversity and structure of benthic macroinvertebrates in Aby Lagoon (Ivory Coast, West Africa).

    PubMed

    Kouadio, K N; Diomandé, D; Ouattara, A; Koné, Y J M; Gourène, G

    2008-09-15

    The benthic macroinvertebrates of Aby lagoon (West Africa: Ivory coast) was studied during four seasons (high dry season, high rainy season, low dry season and low rainy season, respectively) from June 2006 to March 2007. The distribution of the benthic macroinvertebrates species was recorded at 13 stations on the whole of the lagoon. A total of 62 taxa of benthic macroinvertebrates belonging to 28 families and 10 orders were listed. The molluscs and crustaceans dominate qualitatively by adding up 51 and 24%, respectively of the total number of organisms. Five taxa (Corbula trigona (20%), Pachymelania aurita (12%), Clibernhardius cooki (7%), Oligochaeta (7%) and Crassostrea gasar (6%) accounted for 52% of total abundance. Classification analysis used to perform the characterisation of the lagoon on the basis of benthic macroinvertebrates showed the existence of four main clusters in which the seasonal pattern in benthic macroinvertebrates were very similar in the four seasons. In contrast the species richness and diversity indices were significantly different. Furthermore these indices where higher in the stations closer to the sea and surrounded by mangrove trees (southern area) compared to the inland ones.

  18. New Tooth Enamel Isotopic Data from the West Coast of South Africa and a Comparison of Terrestrial and Marine Records of Plio-Pleistocene Climate Change

    NASA Astrophysics Data System (ADS)

    Lehmann, S. B.; Levin, N. E.; Stynder, D. D.; Bishop, L. C.; Forrest, F.; Braun, D. R.

    2012-12-01

    The Plio-Pleistocene transition marks a change in the Earth's climate from relative global warmth to colder temperatures with the initiation of glacial-interglacial cycles. Proxy records from marine cores off SW Africa archive changes in ocean upwelling and terrestrial vegetation that suggest increased aridity across the Plio-Pleistocene transition. Today, the SW African coast has a Winter Rainfall Zone (WRZ) and is dominated by C3 vegetation, which results from the regional high-pressure system and upwelling in the Benguela Current. While marine records provide an integrated perspective on regional responses to global climate change, terrestrial paleoclimate records are needed to assess the effects of these changes in a heterogeneous environment like southern Africa. Archeological and paleontological sites can provide useful proxies of paleoclimate, but many southern African sites are poorly dated or postdate the Plio-Pleistocene transition. Langebaanweg (LBW, ~5 Ma) and Elandsfontein (EFT, ~1.0-0.6 Ma) are sites on the SW coast of South Africa that are rich in fossil mammals and represent landscapes where surface water was more prevalent than it is in today's dry coastal environment. Fossil teeth of large herbivores (e.g. hippopotamids, giraffids, bovids, rhinocerotids, suids and equids) are preserved at both sites and enable isotopic studies of vegetation and climate across the Plio-Pleistocene transition. In this study, carbon and oxygen isotopic data are reported for 100 fossil teeth (11 herbivore taxa) at EFT and are compared to published isotopic data from early Pliocene teeth from LBW for many of the same genera. δ13C values of the EFT tooth enamel range from 13 to 8‰ (VPDB) and δ18O values range from -2 to +3‰ (VPDB). Among the EFT data, there are consistent differences in the distribution of both δ13C and δ18O values among the sampled taxa. When the EFT and LBW isotopic results are compared, δ13C values from the two sites are similar within each

  19. 75 FR 11515 - Fisheries Off West Coast States and in the Western Pacific; Pacific Coast Groundfish Fishery...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-11

    ... Western Pacific; Pacific Coast Groundfish Fishery; Application for an Exempted Fishing Permit AGENCY... to retain prohibited species until offloading. EFPs are also needed to allow first receivers to... species catch until offloading. These activities are otherwise prohibited by regulations at 50 CFR...

  20. Spatio-temporal evolution of the West African monsoon during the last deglaciation

    NASA Astrophysics Data System (ADS)

    Weldeab, Syee; Frank, Martin; Stichel, Torben; Haley, Brian; Sangen, Mark

    2011-07-01

    On the basis of a multi-proxy data set from the Gulf of Guinea (eastern equatorial Atlantic) we reconstruct the spatio-temporal evolution of the West African monsoon (WAM) and present evidence for a decoupling between latitudinal shifts of the rain belt and WAM intensification. The onset of deglacial monsoon invigoration at ˜16,600 years before present lagged northward migration of a weak rainfall zone by ˜2800 years. Conversely, during the Younger Dryas (YD) time interval, WAM precipitation was severely reduced but we find no evidence for a large-scale retreat of the rainfall front. This observation is not in agreement with the hypothesis of a large-scale shift of the intertropical convergence zone south of the tropical WAM region during the YD. Our results can be better reconciled with the newly emerging concept of a strong influence of Tropical Easterly and African Easterly Jets on modern WAM.

  1. Spreading patterns of the invasive Caulerpa cylindracea Sonder along the west Istrian Coast (northern Adriatic Sea, Croatia).

    PubMed

    Iveša, Ljiljana; Djakovac, Tamara; Devescovi, Massimo

    2015-06-01

    The northern Adriatic Sea represents the northernmost and thus the coldest biogeographic sector of the Mediterranean Sea. In 2004, the invasive green alga Caulerpa cylindracea was recorded for the first time in the northern Adriatic at a site of the west Istrian Coast. Until 2010, additional C. cylindracea mats have only formed up to 7 km northward from the first colonisation site. Subsequently, the alga was also recorded at sites widespread along the entire coast. Both the first 2004 colonisation event and the 2011-2014 colonisation of distant sites occurred during periods of winter seawater temperatures higher than 9 °C. In general, algal spreading was markedly slow. Approximately 10 years after the first record, C. cylindracea has affected less than 1% of the entire west Istrian coastline. The colonisation predominantly occurred in ports and urbanised bays (seaside resorts) suggesting that anthropogenic activities might enhance algal diffusion.

  2. Spreading patterns of the invasive Caulerpa cylindracea Sonder along the west Istrian Coast (northern Adriatic Sea, Croatia).

    PubMed

    Iveša, Ljiljana; Djakovac, Tamara; Devescovi, Massimo

    2015-06-01

    The northern Adriatic Sea represents the northernmost and thus the coldest biogeographic sector of the Mediterranean Sea. In 2004, the invasive green alga Caulerpa cylindracea was recorded for the first time in the northern Adriatic at a site of the west Istrian Coast. Until 2010, additional C. cylindracea mats have only formed up to 7 km northward from the first colonisation site. Subsequently, the alga was also recorded at sites widespread along the entire coast. Both the first 2004 colonisation event and the 2011-2014 colonisation of distant sites occurred during periods of winter seawater temperatures higher than 9 °C. In general, algal spreading was markedly slow. Approximately 10 years after the first record, C. cylindracea has affected less than 1% of the entire west Istrian coastline. The colonisation predominantly occurred in ports and urbanised bays (seaside resorts) suggesting that anthropogenic activities might enhance algal diffusion. PMID:25828676

  3. On the mathematical analysis of Ebola hemorrhagic fever: deathly infection disease in West African countries.

    PubMed

    Atangana, Abdon; Goufo, Emile Franc Doungmo

    2014-01-01

    For a given West African country, we constructed a model describing the spread of the deathly disease called Ebola hemorrhagic fever. The model was first constructed using the classical derivative and then converted to the generalized version using the beta-derivative. We studied in detail the endemic equilibrium points and provided the Eigen values associated using the Jacobian method. We furthered our investigation by solving the model numerically using an iteration method. The simulations were done in terms of time and beta. The study showed that, for small portion of infected individuals, the whole country could die out in a very short period of time in case there is not good prevention.

  4. Instrumental evidence of an unusually strong West African Monsoon in the 19th century

    NASA Astrophysics Data System (ADS)

    Gallego, David; Ordoñez, Paulina; Ribera, Pedro; Peña-Ortiz, Cristina; Garcia-Herrera, Ricardo; Vega, Inmaculada; Gomez, Francisco de Paula

    2016-04-01

    The precipitation in the Sahel -which is mainly controlled by the dynamics of the West African Monsoon-, has been in the spot of the climate community for the last three decades due to the persistence of the drought period that started in the 1970s. Unfortunately, reliable meteorological series in this area are only available since the beginning of the 20th Century, thus limiting our understanding of the significance of this period from a long term perspective. Currently, our knowledge of what happened in times previous to the 20th Century essentially relies in documentary or proxy sources. In this work, we present the first instrumental evidence of a 50 year-long period characterised by an unusually strong West African monsoon in the19th Century. Following the recent advances in the generation of climatic indices based on data from ship's logbooks, we used historical wind observations to compute a new index (the so-called ASWI) for characterising the strength of the West African Monsoon. The ASWI is based in the persistence of the southwesterly winds in the [29°W-17°W;7°N-13°N] area and it has been possible to compute it since 1790 for July and since 1839 for August and September. We show that the ASWI is a reliable measure of the monsoon's strength and the Sahelian rainfall. Our new series clearly shows the well-known drought period starting in the 1970s. During this dry period, the West African Monsoon was particularly weak and interestingly, we found that since then, the correlations with different climatic patterns such as the Pacific and Atlantic "El Niño" changed significantly in relation to those of the previous century. Remarkably, our results also show that the period 1839-1890 was characterised by an unusually strong and persistent monsoon. Notwithstanding, two of the few dry years within this period were concurrent with large volcanic eruptions in the Northern Hemisphere. This latter result supports the recently suggested relationship between major

  5. Seasonal Evolution and Variability Associated with the West African Monsoon System

    NASA Technical Reports Server (NTRS)

    Gu, Guojun; Adler, Robert F.

    2003-01-01

    In this study, we investigate the seasonal variations in surface rainfall and associated large-scale processes in the tropical eastern Atlantic and West African region. The 5-yr (1998-2002) high-quality TRMM rainfall, sea surface temperature (SST), water vapor and cloud liquid water observations are applied along with the NCEP/NCAR reanalysis wind components and a 3-yr (2000-2002) Quickscat satellite-observed surface wind product. Major mean rainfall over West Africa tends to be concentrated in two regions and is observed in two different seasons, manifesting an abrupt shift of the mean rainfall zone during June-July. (i) Near the Gulf of Guinea (about 5 degN), intense convection and rainfall are seen during April-June and roughly follow the seasonality of SST in the tropical eastern Atlantic. (ii) Along the latitudes of about 10 deg. N over the interior West African continent, a second intense rain belt begins to develop from July and remains there during the later summer season. This belt co-exists with a northwardmoved African Easterly Jet (AEJ) and its accompanying horizonal and vertical shear zones, the appearance and intensification of an upper tropospheric Tropical Easterly Jet (TEJ), and a strong low-level westerly flow. Westward-propagating wave signals [ i e . , African easterly waves (AEWs)] dominate the synoptic-scale variability during July-September, in contrast to the evident eastward-propagating wave signals during May- June. The abrupt shift of mean rainfall zone thus turns out to be a combination of two different physical processes: (i) Evident seasonal cycles in the tropical eastern Atlantic ocean which modulate convection and rainfall in the Gulf of Guinea by means of SST thermal forcing and SST-related meridional gradient; (ii) The interaction among the AEJ, TEJ, low-level westerly flow, moist convection and AEWs during July-September which modulates rainfall variability in the interior West Africa, primarily within the ITCZ rain band. Evident

  6. An assessment of West African seahorses in fisheries catch and trade.

    PubMed

    Cisneros-Montemayor, A M; West, K; Boiro, I S; Vincent, A C J

    2016-02-01

    This study provides the first assessment of a heavily traded West African seahorse species, Hippocampus algiricus, and the first information on short-snouted seahorse Hippocampus hippocampus biology in Africa. A total of 219 seahorses were sampled from fisher catch in Senegal and The Gambia, with estimated height at reproductive activity for H. algiricus (161 mm) larger than mean ± S.D. catch height (150 ± 31 mm). Catch composition, height at reproductive activity and potential biases in fishery retention are discussed with regard to the current Convention on International Trade of Endangered Species (CITES) guidelines.

  7. Preliminary assessment of habitat protection needs for West Indian manatees on the east coast of Florida and Georgia. Final report

    SciTech Connect

    Not Available

    1988-12-01

    The report assesses information on the status of endangered West Indian manatees (Trichechus manatus) on the east coast of Florida and Georgia in the southeastern United States and recommends actions to improve protection of the species and its habitat in that area. Manatees on the east coast of Florida and Georgia appear to constitute a discrete population numbering perhaps 700 to 900 animals. Based on carcass-salvage data, recent annual mortality rates of between 8% and 10% are indicated. Perhaps 3% to 4% of the population was killed as a result of collisions with boats during 1987, and this threat appears to be increasing. Collisions with boats and destruction of essential habitat are the principal threats to the population. Recommendations include: quadruple the size of the boat-speed regulatory system on the east coast of Florida; limit development in essential manatee habitats; acquire additional manatee habitat as additions to Federal and State refuges and preserves.

  8. Establishment of the green mussel, Perna viridis (Linnaeus 1758) (Mollusca: Mytilidae) on the West Coast of Florida

    USGS Publications Warehouse

    Benson, A.J.; Marelli, D.C.; Frischer, M.E.; Danforth, J.M.; Williams, J.D.

    2001-01-01

    In 1999, the green mussel, Perna viridis, was first observed in Tampa Bay, Florida. This was the first reported occurrence of this Indo-Pacific marine bivalve in North America. The mussels found in Tampa Bay were confirmed to be P. viridis based on both morphological and genetic characteristics. Since the initial discovery, surveys in Tampa Bay and on the west coast of Florida have documented the growth, recruitment, and range expansion of P. viridis. From November 1999 to July 2000, the mean shell length of a Tampa Bay population increased from 49.0 mm to 94.1 mm, an increase of 97%. Populations of P. viridis are successfully reproducing in Tampa Bay. Recruitment was observed on sampling plates in May and continued through July 2000. The full extent of mussel colonization is not clear, but mussels were found outside Tampa Bay in St. Petersburg, Florida, south to Venice. Based on these studies it is evident that P. viridis has successfully invaded Tampa Bay and the west coast of Florida. The long-term impact of P. viridis on native communities off the west coast of Florida cannot be predicted at this time.

  9. The unique resistance and resilience of the Nigerian West African Dwarf goat to gastrointestinal nematode infections

    PubMed Central

    2011-01-01

    Background West African Dwarf (WAD) goats serve an important role in the rural village economy of West Africa, especially among small-holder livestock owners. They have been shown to be trypanotolerant and to resist infections with Haemonchus contortus more effectively than any other known breed of goat. Methods In this paper we review what is known about the origins of this goat breed, explain its economic importance in rural West Africa and review the current status of our knowledge about its ability to resist parasitic infections. Conclusions We suggest that its unique capacity to show both trypanotolerance and resistance to gastrointestinal (GI) nematode infections is immunologically based and genetically endowed, and that knowledge of the underlying genes could be exploited to improve the capacity of more productive wool and milk producing, but GI nematode susceptible, breeds of goats to resist infection, without recourse to anthelmintics. Either conventional breeding allowing introgression of resistance alleles into susceptible breeds, or transgenesis could be exploited for this purpose. Appropriate legal protection of the resistance alleles of WAD goats might provide a much needed source of revenue for the countries in West Africa where the WAD goats exist and where currently living standards among rural populations are among the lowest in the world. PMID:21291550

  10. Siple Coast ice streams reorganization following the reactivation of Kamb Ice Stream tributaries, West Antarctica

    NASA Astrophysics Data System (ADS)

    Christoffersen, P.; Bougamont, M. H.; Price, S. F.; Fricker, H. A.; Tulaczyk, S. M.; Carter, S. P.

    2015-12-01

    Ice streams in Antarctica account for most of the ice volume discharged to the ocean, and their flow variability greatly influences the mass balance of the ice sheet. Today, the Siple Coast region is the only one in West Antarctica to experience a positive mass balance of 36 Gt/yr, as a consequence of the stagnation of Kamb Ice Stream 170 years ago as well as the ongoing slowdown of Whillans Ice Stream. However, this positive trend could be temporary, as reconstructions of past flow show that the Siple Coast ice streams have experienced significant flow variability over the past millennia, with episodes of stagnation typically followed by reactivation on a centennial timescale. The impact that this internally induced variability may have on the future mass balance remains unknown. Here, we use the three-dimensional ice sheet model CISM to study the flow variability of the Ross ice streams over a 250 year period, during which the basal properties controlling ice flow evolve according to the distribution of meltwater in a dynamic, regional hydrological system, coupled to a subglacial till layer. To obtain realistic initial flow conditions, we assimilate the 1997 velocity data available for this region. During the forward simulation, all ice streams undergo dynamic changes, traced to persistently weak bed conditions beneath the tributaries of the currently dormant Kamb Ice Stream. This source of regional instability propagates into the catchments of Whillans as well as Bindschadler ice streams within decades, and re-organizes the flow of all the Ross ice streams within two centuries. Ice piracy from Kamb Ice Stream prolongs the fast flow on Whillans Ice Stream, maintaining its trunk active during the first modeled century. At the same time, ice piracy into the catchment of Bindschadler ice stream reactivates the relict Siple Ice Stream, which significantly reduces the mass balance for this region. The trunk of Kamb Ice Stream reactivates last (during the second half

  11. Real-time Tsunami Warning Operations at the NOAA West Coast/Alaska Tsunami Warning Center

    NASA Astrophysics Data System (ADS)

    Whitmore, P.; Huang, P.; Crowley, H.; Ferris, J.; Hale, D.; Knight, W.; Medbery, A.; Nyland, D.; Preller, C.; Turner, B.; Urban, G.

    2007-12-01

    The West Coast/Alaska Tsunami Warning Center (WCATWC) in Palmer, Alaska and the Pacific Tsunami Warning Center (PTWC) in Ewa Beach, Hawaii, provide tsunami warning services for a large portion of the world's coasts. The WCATWC has primary responsibility for providing tsunami detection, warnings, and forecasts to Canada, Puerto Rico, Virgin Islands, and all U.S. States except Hawaii. WCATWC also acts as back-up for the PTWC, requiring the center to constantly monitor global tsunami activities by rapidly detecting and evaluating earthquakes for their tsunamigenic potential. The Centers' goals are to issue initial messages as quickly as possible to alert those near the source to potential danger (assuming there is any), and to follow that with a reasonable forecast of impact level. With these goals in mind, a Watchstander's initial action is based entirely on estimates of tsunami potential from the earthquake's source parameters. The course of action for the first message is determined primarily by the earthquake's magnitude, location, tsunami history, tsunami travel time, estimated threat based on pre-computed models, and pre-set criteria. Supplemental messages, if necessary, are based on wave observations and forecasts generated from hydrodynamic models (which are calibrated with near real-time observations). In April 2006, the WCATWC increased staff level so that the Center can be staffed 24/7 with two watchstanders. Since then, the Center's response time for events within the primary area-of-responsibility has decreased to less than 5 minutes. In order to illustrate the WCATWC's real time tsunami warning operational environment, tsunami warning operation timelines for several tsunamigenic earthquakes - including the September 12 southern Sumatra 8.4 and the January 13 Kuril Island 8.1 earthquakes - are provided. The timelines highlight the key parameters and observations that guide tsunami warning operations chronicling the event through: 1) initial alarm, 2

  12. Compiling Multibeam Sonar data for the U.S. Pacific West Coast Extended Continental Shelf Project

    NASA Astrophysics Data System (ADS)

    Lim, E.; Gardner, J. V.; Henderson, J. F.

    2011-12-01

    The United States Extended Continental Shelf (ECS) Project is a multi-agency collaboration whose goals are to determine and define a potential extension of the U.S. continental shelf beyond 200 nautical miles (nmi). Under international law as reflected in the 1982 United Nations Convention on the Law of the Sea (UNCLOS), every coastal state is entitled to a continental shelf out to 200 nmi (the Exclusive Economic Zone) from its coastal baseline or out to a maritime boundary with another coastal country. The extended continental shelf (ECS) is the area that lies beyond this 200 nm limit where a country could gain sovereign rights to the resources of the seafloor and sub-seafloor. In 2007, the U.S. ECS Task Force designated NOAA's National Geophysical Data Center (NGDC) as the Data Management lead for the U.S. ECS Project and the data stewards and archival location for all data related to this project. The process to determine the outer limits of the ECS requires the collection and analysis of data that describe the depth, shape, and geophysical characteristics of the seafloor and sub-seafloor, as well as the thickness of the underlying sediments. The specific types of data that need to be collected include bathymetric data, seismic profiles, magnetic and gravity data, and other geophysical data. NGDC maintains several global geophysical databases, including bathymetric, seismic and geological data, all critical for supporting ECS analysis. Multibeam bathymetry is a primary dataset used for ECS analysis. Since 2003, the U.S. has collected more than 1.65 million square kilometers of multibeam bathymetric data from 18 cruises. One area where new data has been collected and where the U.S. may have an extended continental shelf is off the U.S. Pacific West Coast. New and old multibeam bathymetry archived at and delivered by NGDC were individually gridded by survey for an area within 48-30 degrees north latitude and -140 and -115 west longitude at a resolution of 210

  13. 77 FR 16048 - U.S. Customs and Border Protection 2012 West Coast Trade Symposium: “Harmonizing Trade for a...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-19

    ... Symposium: ``Harmonizing Trade for a Stronger Economy'' AGENCY: U.S. Customs and Border Protection... Economy.'' This document announces that the West Coast trade symposium will be held in Long...

  14. Hybridising Medicine: Illness, Healing and the Dynamics of Reciprocal Exchange on the Upper Guinea Coast (West Africa).

    PubMed

    Havik, Philip J

    2016-04-01

    The present article seeks to fill a number of lacunae with regard to the study of the circulation and assimilation of different bodies of medical knowledge in an important cultural contact zone, that is the Upper Guinea Coast. Building upon ongoing research on trade and cultural brokerage in the area, it focuses upon shifting attitudes and practices with regard to health and healing as a result of cultural interaction and hybridisation against the background of growing intra-African and Afro-Atlantic interaction from the fifteenth to the late seventeenth century. Largely based upon travel accounts, missionary reports and documents produced by the Portuguese Inquisition, it shows how forms of medical knowledge shifted and circulated between littoral areas and their hinterland, as well as between the coast, the Atlantic and beyond. It shows that the changing patterns of trade, migration and settlement associated with Mandé influence and Afro-Atlantic exchange had a decisive impact on changing notions of illness and therapeutic trajectories. Over the centuries, cross-cultural, reciprocal borrowing contributed to the development of healing kits employed by Africans and non-African outsiders alike, which were used and brokered by local communities in different locations in the region.

  15. Hybridising Medicine: Illness, Healing and the Dynamics of Reciprocal Exchange on the Upper Guinea Coast (West Africa).

    PubMed

    Havik, Philip J

    2016-04-01

    The present article seeks to fill a number of lacunae with regard to the study of the circulation and assimilation of different bodies of medical knowledge in an important cultural contact zone, that is the Upper Guinea Coast. Building upon ongoing research on trade and cultural brokerage in the area, it focuses upon shifting attitudes and practices with regard to health and healing as a result of cultural interaction and hybridisation against the background of growing intra-African and Afro-Atlantic interaction from the fifteenth to the late seventeenth century. Largely based upon travel accounts, missionary reports and documents produced by the Portuguese Inquisition, it shows how forms of medical knowledge shifted and circulated between littoral areas and their hinterland, as well as between the coast, the Atlantic and beyond. It shows that the changing patterns of trade, migration and settlement associated with Mandé influence and Afro-Atlantic exchange had a decisive impact on changing notions of illness and therapeutic trajectories. Over the centuries, cross-cultural, reciprocal borrowing contributed to the development of healing kits employed by Africans and non-African outsiders alike, which were used and brokered by local communities in different locations in the region. PMID:26971596

  16. Hybridising Medicine: Illness, Healing and the Dynamics of Reciprocal Exchange on the Upper Guinea Coast (West Africa)

    PubMed Central

    Havik, Philip J.

    2016-01-01

    The present article seeks to fill a number of lacunae with regard to the study of the circulation and assimilation of different bodies of medical knowledge in an important cultural contact zone, that is the Upper Guinea Coast. Building upon ongoing research on trade and cultural brokerage in the area, it focuses upon shifting attitudes and practices with regard to health and healing as a result of cultural interaction and hybridisation against the background of growing intra-African and Afro-Atlantic interaction from the fifteenth to the late seventeenth century. Largely based upon travel accounts, missionary reports and documents produced by the Portuguese Inquisition, it shows how forms of medical knowledge shifted and circulated between littoral areas and their hinterland, as well as between the coast, the Atlantic and beyond. It shows that the changing patterns of trade, migration and settlement associated with Mandé influence and Afro-Atlantic exchange had a decisive impact on changing notions of illness and therapeutic trajectories. Over the centuries, cross-cultural, reciprocal borrowing contributed to the development of healing kits employed by Africans and non-African outsiders alike, which were used and brokered by local communities in different locations in the region. PMID:26971596

  17. The Contribution of Occult Precipitation to Nutrient Deposition on the West Coast of South Africa

    PubMed Central

    2015-01-01

    The Strandveld mediterranean-ecosystem of the west coast of South Africa supports floristically diverse vegetation growing on mostly nutrient-poor aeolian sands and extending from the Atlantic Ocean tens of kilometers inland. The cold Benguela current upwelling interacts with warm onshore southerly winds in summer causing coastal fogs in this region. We hypothesized that fog and other forms of occult precipitation contribute moisture and nutrients to the vegetation. We measured occult precipitation over one year along a transect running inland in the direction of the prevailing wind and compared the nutrient concentrations with those in rainwater. Occult deposition rates of P, N, K, Mg, Ca, Na, Al and Fe all decreased with distance from the ocean. Furthermore, ratios of cations to Na were similar to those of seawater, suggesting a marine origin for these. In contrast, N and P ratios in occult precipitation were higher than in seawater. We speculate that this is due to marine foam contributing to occult precipitation. Nutrient loss in leaf litter from dominant shrub species was measured to indicate nutrient demand. We estimated that occult precipitation could meet the demand of the dominant shrubby species for annual N, P, K and Ca. Of these species, those with small leaves intercepted more moisture and nutrients than those with larger leaves and could take up foliar deposits of glycine, NO3-, NH4+ and Li (as tracer for K) through leaf surfaces. We conclude that occult deposition together with rainfall deposition are potentially important nutrient and moisture sources for the Strandveld vegetation that contribute to this vegetation being floristically distinct from neighbouring nutrient-poor Fynbos vegetation. PMID:26017747

  18. Climate change alters plant biogeography in Mediterranean prairies along the West Coast, USA.

    PubMed

    Pfeifer-Meister, Laurel; Bridgham, Scott D; Reynolds, Lorien L; Goklany, Maya E; Wilson, Hannah E; Little, Chelsea J; Ferguson, Aryana; Johnson, Bart R

    2016-02-01

    Projected changes in climate are expected to have widespread effects on plant community composition and diversity in coming decades. However, multisite, multifactor climate manipulation studies that have examined whether observed responses are regionally consistent and whether multiple climate perturbations are interdependent are rare. Using such an experiment, we quantified how warming and increased precipitation intensity affect the relative dominance of plant functional groups and diversity across a broad climate gradient of Mediterranean prairies. We implemented a fully factorial climate manipulation of warming (+2.5-3.0 °C) and increased wet-season precipitation (+20%) at three sites across a 520-km latitudinal gradient in the Pacific Northwest, USA. After seeding with a nearly identical mix of native species at all sites, we measured plant community composition (i.e., cover, richness, and diversity), temperature, and soil moisture for 3 years. Warming and the resultant drying of soils altered plant community composition, decreased native diversity, and increased total cover, with warmed northern communities becoming more similar to communities further south. In particular, after two full years of warming, annual cover increased and forb cover decreased at all sites mirroring the natural biogeographic pattern. This suggests that the extant climate gradient of increasing heat and drought severity is responsible for a large part of the observed biogeographic pattern of increasing annual invasion in US West Coast prairies as one moves further south. Additional precipitation during the rainy season did little to relieve drought stress and had minimal effects on plant community composition. Our results suggest that the projected increase in drought severity (i.e., hotter, drier summers) in Pacific Northwest prairies may lead to increased invasion by annuals and a loss of forbs, similar to what has been observed in central and southern California, resulting in

  19. Physicochemical and Phytochemical Analyses of Copra and Oil of Cocos nucifera L. (West Coast Tall Variety).

    PubMed

    Ghosh, Probir Kumar; Bhattacharjee, Paramita; Mitra, Souvik; Poddar-Sarkar, Mousumi

    2014-01-01

    Coconut copra from West coast tall variety, cultivated in Kerala, India, was subjected to aqueous and solvent extractions (using n-hexane). Additionally, oil was extracted from the copra in Soxhlet assembly using petroleum ether (b.p. 60-80°C). Physicochemical and phytochemical analyses were conducted for the extracts and the oil, with commercial coconut oil as the experimental control. The physicochemical analyses showed that the aqueous extract of copra was milky-white in color with a sweet odor, while the solvent extract was pale yellow and odorless. The commercial oil had 0.08 ± 0.02% oleic acid and a TOTOX value of 7.73 ± 0.78, lower than the Soxhlet extracted oil. Among all the extracts and oils, best phytochemical properties, antioxidant activity (DPPH activity, IC50 value 0.04 ± 0.01 mg/mL), total phenol (0.96 ± 0.04 mg gallic acid eq./g dry copra), reducing power (40.49 ± 1.84 mg BHT eq./g dry copra), and anti-inflammatory activity (NO activity, IC50  value 0.77 ± 0.06 mg/mL) were obtained in the commercial coconut oil, followed by the Soxhlet extracted oil, aqueous extract, and solvent extract. Fatty acid composition analyses showed mainly medium chain fatty acids in the copra oil with lauric acid as the predominant fatty acid (51.88% and 44.84% in Soxhlet extracted and commercial oils, resp.).

  20. The contribution of occult precipitation to nutrient deposition on the west coast of South Africa.

    PubMed

    Nyaga, Justine M; Neff, Jason C; Cramer, Michael D

    2015-01-01

    The Strandveld mediterranean-ecosystem of the west coast of South Africa supports floristically diverse vegetation growing on mostly nutrient-poor aeolian sands and extending from the Atlantic Ocean tens of kilometers inland. The cold Benguela current upwelling interacts with warm onshore southerly winds in summer causing coastal fogs in this region. We hypothesized that fog and other forms of occult precipitation contribute moisture and nutrients to the vegetation. We measured occult precipitation over one year along a transect running inland in the direction of the prevailing wind and compared the nutrient concentrations with those in rainwater. Occult deposition rates of P, N, K, Mg, Ca, Na, Al and Fe all decreased with distance from the ocean. Furthermore, ratios of cations to Na were similar to those of seawater, suggesting a marine origin for these. In contrast, N and P ratios in occult precipitation were higher than in seawater. We speculate that this is due to marine foam contributing to occult precipitation. Nutrient loss in leaf litter from dominant shrub species was measured to indicate nutrient demand. We estimated that occult precipitation could meet the demand of the dominant shrubby species for annual N, P, K and Ca. Of these species, those with small leaves intercepted more moisture and nutrients than those with larger leaves and could take up foliar deposits of glycine, NO3(-), NH4(+) and Li (as tracer for K) through leaf surfaces. We conclude that occult deposition together with rainfall deposition are potentially important nutrient and moisture sources for the Strandveld vegetation that contribute to this vegetation being floristically distinct from neighbouring nutrient-poor Fynbos vegetation.

  1. Predicted Deep-Sea Coral Habitat Suitability for the U.S. West Coast

    PubMed Central

    Guinotte, John M.; Davies, Andrew J.

    2014-01-01

    Regional scale habitat suitability models provide finer scale resolution and more focused predictions of where organisms may occur. Previous modelling approaches have focused primarily on local and/or global scales, while regional scale models have been relatively few. In this study, regional scale predictive habitat models are presented for deep-sea corals for the U.S. West Coast (California, Oregon and Washington). Model results are intended to aid in future research or mapping efforts and to assess potential coral habitat suitability both within and outside existing bottom trawl closures (i.e. Essential Fish Habitat (EFH)) and identify suitable habitat within U.S. National Marine Sanctuaries (NMS). Deep-sea coral habitat suitability was modelled at 500 m×500 m spatial resolution using a range of physical, chemical and environmental variables known or thought to influence the distribution of deep-sea corals. Using a spatial partitioning cross-validation approach, maximum entropy models identified slope, temperature, salinity and depth as important predictors for most deep-sea coral taxa. Large areas of highly suitable deep-sea coral habitat were predicted both within and outside of existing bottom trawl closures and NMS boundaries. Predicted habitat suitability over regional scales are not currently able to identify coral areas with pin point accuracy and probably overpredict actual coral distribution due to model limitations and unincorporated variables (i.e. data on distribution of hard substrate) that are known to limit their distribution. Predicted habitat results should be used in conjunction with multibeam bathymetry, geological mapping and other tools to guide future research efforts to areas with the highest probability of harboring deep-sea corals. Field validation of predicted habitat is needed to quantify model accuracy, particularly in areas that have not been sampled. PMID:24759613

  2. Assessment of mangroves from Goa, west coast India using DNA barcode.

    PubMed

    Saddhe, Ankush Ashok; Jamdade, Rahul Arvind; Kumar, Kundan

    2016-01-01

    Mangroves are salt-tolerant forest ecosystems of tropical and subtropical intertidal regions. They are among most productive, diverse, biologically important ecosystem and inclined toward threatened system. Identification of mangrove species is of critical importance in conserving and utilizing biodiversity, which apparently hindered by a lack of taxonomic expertise. In recent years, DNA barcoding using plastid markers rbcL and matK has been suggested as an effective method to enrich traditional taxonomic expertise for rapid species identification and biodiversity inventories. In the present study, we performed assessment of available 14 mangrove species of Goa, west coast India based on core DNA barcode markers, rbcL and matK. PCR amplification success rate, intra- and inter-specific genetic distance variation and the correct identification percentage were taken into account to assess candidate barcode regions. PCR and sequence success rate were high in rbcL (97.7 %) and matK (95.5 %) region. The two candidate chloroplast barcoding regions (rbcL, matK) yielded barcode gaps. Our results clearly demonstrated that matK locus assigned highest correct identification rates (72.09 %) based on TaxonDNA Best Match criteria. The concatenated rbcL + matK loci were able to adequately discriminate all mangrove genera and species to some extent except those in Rhizophora, Sonneratia and Avicennia. Our study provides the first endorsement of the species resolution among mangroves using plastid genes with few exceptions. Our future work will be focused on evaluation of other barcode markers to delineate complete resolution of mangrove species and identification of putative hybrids. PMID:27652127

  3. Volatility of aerosol at Mace Head, on the west coast of Ireland

    SciTech Connect

    Jennings, S.G.; O'Dowd, C.D. )

    1990-08-20

    Volatile properties of maritime and modified maritime aerosol were measured at the remote site at Mace Head (53{degree}19{prime}N, 9{degree}54{prime}W) on the west coast of Ireland, located on the eastern edge of the North Atlantic Ocean. The volatility measurements were made with a light-scattering counter equipped with a temperature-controlled heated inlet. The work extends the temperature range from 300{degree}C to 850{degree}C for the first time for aerosol volatility studies. Representative measurements made over the period of about a year show that the submicrometer particles with radius <0.2 {mu}m are highly volatile for the maritime aerosol and show temperature fractionation features of ammonium sulfate (or ammonium bisulfate). It is estimated that 85-95% of this size fraction (by volume) is composed of these sulfates. For the higher temperatures, temperature-fractionation characteristics of sodium chloride are shown for the supermicron and also the submicron maritime particles. About 80% of the particle size interval of 0.3-1.5 {mu}m radius is composed of sodium chloride. The temperature profile curves for the modified maritime aerosol, which has made a partial traverse overland, do not display definitive features characteristic of known atmospheric constituents such as ammonium sulfate or sodium chloride, but rather properties indicative of mixtures of these species with other unknown constituents. For both airmasses, between about 5% and 30% (by volume) of the aerosol particles remain involatile at least up to a temperature of 850{degree}C.

  4. Assessment of mangroves from Goa, west coast India using DNA barcode.

    PubMed

    Saddhe, Ankush Ashok; Jamdade, Rahul Arvind; Kumar, Kundan

    2016-01-01

    Mangroves are salt-tolerant forest ecosystems of tropical and subtropical intertidal regions. They are among most productive, diverse, biologically important ecosystem and inclined toward threatened system. Identification of mangrove species is of critical importance in conserving and utilizing biodiversity, which apparently hindered by a lack of taxonomic expertise. In recent years, DNA barcoding using plastid markers rbcL and matK has been suggested as an effective method to enrich traditional taxonomic expertise for rapid species identification and biodiversity inventories. In the present study, we performed assessment of available 14 mangrove species of Goa, west coast India based on core DNA barcode markers, rbcL and matK. PCR amplification success rate, intra- and inter-specific genetic distance variation and the correct identification percentage were taken into account to assess candidate barcode regions. PCR and sequence success rate were high in rbcL (97.7 %) and matK (95.5 %) region. The two candidate chloroplast barcoding regions (rbcL, matK) yielded barcode gaps. Our results clearly demonstrated that matK locus assigned highest correct identification rates (72.09 %) based on TaxonDNA Best Match criteria. The concatenated rbcL + matK loci were able to adequately discriminate all mangrove genera and species to some extent except those in Rhizophora, Sonneratia and Avicennia. Our study provides the first endorsement of the species resolution among mangroves using plastid genes with few exceptions. Our future work will be focused on evaluation of other barcode markers to delineate complete resolution of mangrove species and identification of putative hybrids.

  5. GLORIA mosaic of West Coast US Exclusive Economic Zone, northern sector

    SciTech Connect

    Hampton, M.A.; Cacchione, D.A.; Drake, D.E.; Karl, N.H.; Kenyon, N.H.; Masson, D.G.

    1986-05-01

    The GLORIA (Geological Long-Range Inclined Asdic) side-scanning sonar system was used to compile an image-enhanced acoustic mosaic, similar to an aerial photograph, of the sea floor of the West Coast US Exclusive Economic Zone. The mosaic clearly shows the spreading centers, fracture zones, submarine fans and channels, and transform to convergent continental margins north of latitude 39/sup 0/N. The linear basement ridges originally generated at the Gorda and Juan de Fuca spreading centers are abruptly truncated by the Mendocino and Blanco fracture zones, and their subtle to distinct divergence, bending, and offset attests to past changes in spreading rate and propagation of spreading centers. The major Delgada, Astoria, and Nitinat fans are traversed by lengthy channel-levee complexes extending from major canyons on the adjacent continental slope; areally extensive sediment-wave fields occur adjacent to the right side (facing down-channel) of these complexes. Other drainage features appear on the mosaic, and the range of channel sinuosity and continuity indicates fluvial-like processes at work on the sea floor. Submarine canyons on the continental slope are irregularly distributed; their range of maturity and relation to substrate type and geologic structure are manifest as variations in length, width, and relief, by changes in trend, and by the degree of sidewall gullying. Compressional and diapiric ridges characterize the continental slope in areas of plate convergence, whereas along the transform margin south of the Mendocino fracture zone, the slope is relatively smooth and featureless, except where incised by large canyon systems.

  6. Daily characteristics of West African summer monsoon precipitation in CORDEX simulations

    NASA Astrophysics Data System (ADS)

    Klutse, Nana Ama Browne; Sylla, Mouhamadou Bamba; Diallo, Ismaila; Sarr, Abdoulaye; Dosio, Alessandro; Diedhiou, Arona; Kamga, Andre; Lamptey, Benjamin; Ali, Abdou; Gbobaniyi, Emiola O.; Owusu, Kwadwo; Lennard, Christopher; Hewitson, Bruce; Nikulin, Grigory; Panitz, Hans-Jürgen; Büchner, Matthias

    2016-01-01

    We analyze and intercompare the performance of a set of ten regional climate models (RCMs) along with the ensemble mean of their statistics in simulating daily precipitation characteristics during the West African monsoon (WAM) period (June-July-August-September). The experiments are conducted within the framework of the COordinated Regional Downscaling Experiments for the African domain. We find that the RCMs exhibit substantial differences that are associated with a wide range of estimates of higher-order statistics, such as intensity, frequency, and daily extremes mostly driven by the convective scheme employed. For instance, a number of the RCMs simulate a similar number of wet days compared to observations but greater rainfall intensity, especially in oceanic regions adjacent to the Guinea Highlands because of a larger number of heavy precipitation events. Other models exhibit a higher wet-day frequency but much lower rainfall intensity over West Africa due to the occurrence of less frequent heavy rainfall events. This indicates the existence of large uncertainties related to the simulation of daily rainfall characteristics by the RCMs. The ensemble mean of the indices substantially improves the RCMs' simulated frequency and intensity of precipitation events, moderately outperforms that of the 95th percentile, and provides mixed benefits for the dry and wet spells. Although the ensemble mean improved results cannot be generalized, such an approach produces encouraging results and can help, to some extent, to improve the robustness of the response of the WAM daily precipitation to the anthropogenic greenhouse gas warming.

  7. Geographical assessment of body measurements and qualitative traits in West African cattle.

    PubMed

    Traoré, Amadou; Koudandé, Delphin Oloronto; Fernández, Iván; Soudré, Albert; Granda, Víctor; Álvarez, Isabel; Diarra, Siaka; Diarra, Fousseyni; Kaboré, Adama; Sanou, Moumouni; Tamboura, Hamidou Hamadou; Goyache, Félix

    2015-12-01

    A total of 1015 adult cows belonging to nine West African cattle breeds were assessed for 16 body measurements and 18 qualitative traits to ascertain the existence of geographical patterns of variation. Sampling was carried out in 29 different provinces of Mali, Burkina Faso and Benin. For body measurements, taurine breeds took lower average values than the zebu breeds. Sanga cattle took intermediate values. Qualitative traits did not allow to differentiate among cattle groups (taurine, zebu or sanga) or breeds. Principal component analysis identified two factors explaining 56.4 and 9.2 % of the variance for body measurements, respectively. Two correspondence analysis dimensions computed on qualitative traits explained a small proportion of the variability (20.8 and 13.5 %, respectively). Contour plots were constructed using the eigenvalues computed for each individual and either factor or dimension identified; confidence regions calculated confirmed that body measurements clearly differentiated zebu and taurine cattle breeds while qualitative traits did not. Factor 1 was projected on a geographical map, using provinces as nodes, to assess breed-free variation for body measurements. A pattern of continuous variation from the Sahel area southwards was identified. Probably, breeding decisions promoting the crosses between zebu-like and taurine cattle are underlying this geographical pattern of variation. The implementation of selection strategies aiming at the increase of the productivity of native West African taurine cattle breeds while avoiding looses in trypanotolerant ability would be highly advisable.

  8. 155,000 years of West African monsoon and ocean thermal evolution.

    PubMed

    Weldeab, Syee; Lea, David W; Schneider, Ralph R; Andersen, Nils

    2007-06-01

    A detailed reconstruction of West African monsoon hydrology over the past 155,000 years suggests a close linkage to northern high-latitude climate oscillations. Ba/Ca ratio and oxygen isotope composition of planktonic foraminifera in a marine sediment core from the Gulf of Guinea, in the eastern equatorial Atlantic (EEA), reveal centennial-scale variations of riverine freshwater input that are synchronous with northern high-latitude stadials and interstadials of the penultimate interglacial and the last deglaciation. EEA Mg/Ca-based sea surface temperatures (SSTs) were decoupled from northern high-latitude millennial-scale fluctuation and primarily responded to changes in atmospheric greenhouse gases and low-latitude solar insolation. The onset of enhanced monsoon precipitation lags behind the changes in EEA SSTs by up to 7000 years during glacial-interglacial transitions. This study demonstrates that the stadial-interstadial and deglacial climate instability of the northern high latitudes exerts dominant control on the West African monsoon dynamics through an atmospheric linkage. PMID:17540896

  9. Dyslipidaemia related to insulin resistance and cardiovascular disease in South Asian and West African populations.

    PubMed

    Ewang-Emukowhate, Mfon; Perera, Dilinika; Wierzbicki, Anthony S D M

    2014-01-01

    The global burden of diabetes and cardiovascular disease (CVD) is increasing. Obesity is rapidly increasing worldwide and is associated with dyslipidaemia, metabolic syndrome (MetS) and type 2 diabetes (T2DM). Excess risks of T2DM and CVD are found in migrant Indian Asian and West African populations but with increasing urbanization similar changes are occurring in the original populations and are likely to predispose to a large increase in worldwide burden of CVD. Genetic and environmental factors interacting together play a role in the lipid patterns observed. Dyslipidaemia in the MetS associated with insulin resistance is characterised by an atherogenic lipid profile comprising elevated triglycerides, low high density lipoprotein cholesterol (HDL-C) and increased numbers of small dense low density lipoprotein particles. The pattern of dyslipidaemia varies across different ethnic groups with increases in triglycerides and a reduction in HDL-C being the commonest pattern in non-Caucasians. This review surveys the literature on dyslipidaemia in Indian Asian and West African populations and how it relates to CVD risk in those populations. It is important that dyslipidaemia and other conventional risk factors for CVD are adequately addressed and managed especially in high-risk populations. PMID:24953401

  10. Influence of Arctic sea-ice and greenhouse gas concentration change on the West African Monsoon.

    NASA Astrophysics Data System (ADS)

    Monerie, Paul-Arthur; Oudar, Thomas; Sanchez-Gomez, Emilia; Terray, Laurent

    2016-04-01

    The Sahelian precipitation are projected to increase in the CNRM-CM5 coupled climate model due to a strengthening of the land-Sea temperature gradient, the increase in the North Atlantic temperature and the deepening of the Heat Low. Arctic Sea-Ice loss impacts the low-level atmospheric circulation through a decrease in the northward heat transport. Some authors have linked the sea-ice loss to a poleward shift of the InterTropical Convergence Zone. Within the CMIP5 models the effect of these mechanisms are not distinguishable and it is difficult to understand the effect of the Arctic sea-ice loss on the West African Monsoon so far. We performed several sensitivity experiments with the CNRM-CM5 coupled climate models by modifying the arctic sea-ice extent and/or the greenhouse gas concentration. We then investigated separately the impact of Arctic sea-ice loss and greenhouse gas concentration increases on the West African Monsoon. The increase in greenhouse gas explains the northward shift and the strengthening of the monsoon. Its effect is stronger with a sea-ice free Arctic that leads to an increase in North Atlantic temperature and in Sahelian precipitation at the end of the rainy season (September-October). We argue that the decrease in sea-ice extent, in the context of the global warming, may moistens the Sahel during the rainy season by changing the pressure, winds and moisture fluxes at low-level.

  11. A new perspective on West African hydroclimate during the last deglaciation

    NASA Astrophysics Data System (ADS)

    Parker, Andrew O.; Schmidt, Matthew W.; Jobe, Zane R.; Slowey, Niall C.

    2016-09-01

    Widespread drought characterized the Heinrich 1 and Younger Dryas cold periods of the last deglaciation throughout much of Africa, causing large increases in dust emissions from the Sahara and Sahel. At the same time, increases in wind strength may have also contributed to dust flux, making it difficult to interpret dust records alone as reflecting changes in rainfall over the region. The Niger River has the third largest drainage basin in Africa and drains most of the Sahara and Sahel and thus preserves and propagates climatic signals. Here, we present new reconstructions of Niger Delta sea surface salinity and Niger River discharge for the last 20,000 years in order to more accurately reconstruct the onset of the Western African Monsoon system. Based on calculated δ18OSEAWATER (δ18OSW) and measured Ba/Ca ratios in planktonic foraminifera, these new records reflect changes in sub-Saharan precipitation across the Niger River Basin in West Africa and reveal that the West African Monsoon system began to intensify several thousand years after the equatorial Monsoon system in Central Africa. We also present new records of primary productivity in the Niger Delta that are related to wind-driven upwelling and show that productivity is decoupled from changes in Niger River discharge. Our results suggest that wind strength, rather than changes in monsoon moisture, was the primary driver of dust emissions from the Sahara and Sahel across the last deglaciation.

  12. Comparative Response of the West African Dwarf Goats to Experimental Infections with Red Sokoto and West African Dwarf Goat Isolates of Haemonchus contortus.

    PubMed

    Ngongeh, Lucas Atehmengo; Onyeabor, Amaechi

    2015-01-01

    Response of the West African Dwarf (WAD) goats to two different isolates of Haemonchus contortus, the Red Sokoto (RS) goat isolate (RSHc) and the WAD goat isolate (WADHc) (isolated from WAD goats), was studied by experimental infections of 4-6-month-old male WAD goat kids. Group 1 and Group 2 goats were each infected with 4500 infective larvae (L3) of RSHc and WADHc, respectively. Group 3 animals served as uninfected control. Prepatent period (PPP), faecal egg counts (FEC), worm burden (WB), body weight (BW), packed cell volume (PCV), and body condition score (BCS) were determined. WAD goats infected with RSHc isolate and the ones infected with WADHc isolate had mean PPP of 19.63 ± 0.26 and 19.50 ± 0.19, respectively. Goats infected with WADHc isolate had significantly higher FEC (P = 0.004) and WB (P = 0.001). BW were significantly higher (P = 0.004) both in the controls and in Group 2 goats infected with WADHc isolate than in Group 1 goats infected with the RSHc isolate. BCS of animals in both infected groups dropped significantly (P = 0.001). There was a significant drop in PCV (P = 0.004) of both infected groups in comparison. Both isolates of H. contortus were pathogenic to the host. PMID:26697224

  13. Comparative Response of the West African Dwarf Goats to Experimental Infections with Red Sokoto and West African Dwarf Goat Isolates of Haemonchus contortus.

    PubMed

    Ngongeh, Lucas Atehmengo; Onyeabor, Amaechi

    2015-01-01

    Response of the West African Dwarf (WAD) goats to two different isolates of Haemonchus contortus, the Red Sokoto (RS) goat isolate (RSHc) and the WAD goat isolate (WADHc) (isolated from WAD goats), was studied by experimental infections of 4-6-month-old male WAD goat kids. Group 1 and Group 2 goats were each infected with 4500 infective larvae (L3) of RSHc and WADHc, respectively. Group 3 animals served as uninfected control. Prepatent period (PPP), faecal egg counts (FEC), worm burden (WB), body weight (BW), packed cell volume (PCV), and body condition score (BCS) were determined. WAD goats infected with RSHc isolate and the ones infected with WADHc isolate had mean PPP of 19.63 ± 0.26 and 19.50 ± 0.19, respectively. Goats infected with WADHc isolate had significantly higher FEC (P = 0.004) and WB (P = 0.001). BW were significantly higher (P = 0.004) both in the controls and in Group 2 goats infected with WADHc isolate than in Group 1 goats infected with the RSHc isolate. BCS of animals in both infected groups dropped significantly (P = 0.001). There was a significant drop in PCV (P = 0.004) of both infected groups in comparison. Both isolates of H. contortus were pathogenic to the host.

  14. Comparative Response of the West African Dwarf Goats to Experimental Infections with Red Sokoto and West African Dwarf Goat Isolates of Haemonchus contortus

    PubMed Central

    Ngongeh, Lucas Atehmengo; Onyeabor, Amaechi

    2015-01-01

    Response of the West African Dwarf (WAD) goats to two different isolates of Haemonchus contortus, the Red Sokoto (RS) goat isolate (RSHc) and the WAD goat isolate (WADHc) (isolated from WAD goats), was studied by experimental infections of 4–6-month-old male WAD goat kids. Group 1 and Group 2 goats were each infected with 4500 infective larvae (L3) of RSHc and WADHc, respectively. Group 3 animals served as uninfected control. Prepatent period (PPP), faecal egg counts (FEC), worm burden (WB), body weight (BW), packed cell volume (PCV), and body condition score (BCS) were determined. WAD goats infected with RSHc isolate and the ones infected with WADHc isolate had mean PPP of 19.63 ± 0.26 and 19.50 ± 0.19, respectively. Goats infected with WADHc isolate had significantly higher FEC (P = 0.004) and WB (P = 0.001). BW were significantly higher (P = 0.004) both in the controls and in Group 2 goats infected with WADHc isolate than in Group 1 goats infected with the RSHc isolate. BCS of animals in both infected groups dropped significantly (P = 0.001). There was a significant drop in PCV (P = 0.004) of both infected groups in comparison. Both isolates of H. contortus were pathogenic to the host. PMID:26697224

  15. A modeling system for predicting the impact of severe storms on the U.S. West Coast

    NASA Astrophysics Data System (ADS)

    Barnard, P. L.; Ormondt, M. V.; O'Reilly, B.; Hoover, D.; Hapke, C. J.; Eshleman, J.; Ruggiero, P.; Elias, E.; Erikson, L. H.; Collins, B. D.; Guza, R. T.; Adams, P. N.; Thomas, J.

    2009-12-01

    Storm hazards on the U.S. West Coast are generally thought of as being less severe than the more dramatic hurricane impacts that affect the Gulf of Mexico and East Coasts. However, the magnitude, duration and economic and societal impacts of West Coast storms can still be substantial. Storms during the 1982-83 El Niño winter resulted in 36 casualties and over $1.2 billion in damage to the State of California, and current research suggests that increasing storm intensity, frequency, and wave heights will increase coastal-hazards risks on the West Coast for the foreseeable future. To begin to address the increased risk, the U.S. Geological Survey is leading the development of a modeling system for forecasting the impact of winter storms along the U.S. West Coast. A prototype has been developed for Southern California and is being tested with a hypothetical extreme winter storm scenario designed by atmospheric scientists. The modeling system has been designed to be run operationally or with prescribed scenarios, and utilizes atmospheric forcing information with a suite of state-of-the-art physical process models to provide detailed prediction of ocean currents, deep-water and near-shore wave heights, coastal wave runup, and the resulting total water levels on beaches and cliffed coastlines. Research-grade predictions of coastal flooding, inundation, erosion, and cliff failure are also provided. The modeling system utilizes an integrated, nested structure whereby regional wave and water level models are driven by boundary conditions derived from a global wave model, regional seas and swell data from an extensive wave buoy network, a global tide model from satellite altimetry, and atmospheric pressure and wind forecasts. Wave parameters and water levels from the regional models drive local, high resolution cross-shore profile models and 2D-morphological models. Data from these models, in turn, provide boundary conditions for a Bayesian cliff failure model. This paper

  16. Sst and Ghg Impacts On The West African Monsoon Climate: A Superensemble Approach

    NASA Astrophysics Data System (ADS)

    Paeth, H.; Hense, A.

    West African rainfall has been subject to large interdecadal variations during the 20th century. The most prominent feature is a negative trend in annual precipitation after 1960, causing severe drought in the Sahel region and the southern part of West Africa, with some recoverage in recent years. We examine and quantify the influence of ob- served SST changes on low-frequency variability over the subcontinent and compare it with the additional impact of increasing GHG concentrations, as revealed by a su- perensemble of SST-driven experiments. SST is largely responsible for decadal and longer-term variability over the southern part of West Africa, accounting for almost 80 % of monsoonal rainfall variance. The additional impact of the enhanced green- house effect is weak but statistically significant by the year 1980, obviously associ- ated with a positive trend in annual precipitation. This positive trend is also found in GHG-induced coupled climate model projection into the future. The CO2 signal is again weak but statistically significant and consistent with different climate models, as revealed by a superensemble of coupled experiments.

  17. Seasonal evolution of the West African heat low: a climatological perspective

    NASA Astrophysics Data System (ADS)

    Lavaysse, C.; Flamant, C.; Janicot, S.; Parker, D. J.; Lafore, J.-P.; Sultan, B.; Pelon, J.

    2009-08-01

    The West African heat low (WAHL), a region of high surface temperatures and low surface pressures, is a key element of the West African monsoon system. In this study, we propose a method to detect the WAHL in order to monitor its climatological seasonal displacement over West Africa during the period 1979-2001, using the European Centre for Medium-range Weather Forecast (ECMWF) ERA-40 reanalyses. The low-level atmospheric thickness (LLAT), a variable defined as the difference of geopotential heights at 700 and 925 hPa, is used to detect the dilatation of these levels generated by an increase of the temperature. We define grid points with 10% highest values of the LLAT as the WAHL. We show that our method reliably positions the WAHL over areas of high surface temperatures and low surface pressures, and that it is effective at detecting heat lows. In the course of the year, the climatological WAHL is shown to migrate north-westward from a position south of the Darfur mountains in the winter (November-March) to a location over the Sahara, between the Hoggar and the Atlas mountains, during the summer (June-September). The temperature tendency equation is used to investigate the processes controlling the displacement of the WAHL, and more particularly the heating at low levels. The specific period of the onset of the WAHL in its summer location over the Sahara (referred to as the Saharan heat low -SHL- onset) is also analysed during the 1984-2001 period, using complementary brightness temperature data from the European Union-funded Cloud Archive User Service (CLAUS). The climatological onset of the SHL occurs around 20 June, i.e. just before the climatological monsoon onset date. The present study suggests that the onset of the WAHL occurs approximately 5 days before the monsoon onset for the 1984-2001 period. This is confirmed independently by comparing the SHL onset date and the monsoon onset date for the 1984-2001 period. The seasonal evolution of the WAHL for the

  18. 77 FR 12503 - Magnuson-Stevens Act Provisions; Fisheries off West Coast States; Biennial Specifications and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-01

    ... specifications ] and management measures for most species of the Pacific Coast groundfish fishery (75 FR 67810... species of the Pacific Coast Groundfish Fishery was published on May 11, 2011 (76 FR 27508). This final... action, which published on December 21, 2011 (76 FR 79122). This inseason action contains a...

  19. 78 FR 49190 - Magnuson-Stevens Act Provisions; Fisheries Off West Coast States; Biennial Specifications and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-13

    ... specifications and management measures for most species of the Pacific Coast groundfish fishery (77 FR 67974... species of the Pacific Coast Groundfish Fishery was published on January 3, 2013 (78 FR 580). The Council... management measures are not expected to result in greater impacts to overfished species, except for...

  20. 77 FR 22679 - Magnuson-Stevens Act Provisions; Fisheries off West Coast States; Biennial Specifications and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-17

    ... specifications and management measures for most species of the Pacific Coast groundfish fishery (75 FR 67810... species of the Pacific Coast Groundfish Fishery was published on May 11, 2011 (76 FR 27508). This final rule was subsequently amended by several inseason actions (76 FR 39313, 76 FR 67092, 76 FR 79122, 77...

  1. 77 FR 47322 - Magnuson-Stevens Act Provisions; Fisheries Off West Coast States; Biennial Specifications and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-08

    ... at the Office of the Federal Register's Web site at http://www.gpo.gov/fdsys/search/home.action... specifications and management measures for most species of the Pacific Coast groundfish fishery (75 FR 67810... species of the Pacific Coast Groundfish Fishery was published on May 11, 2011 (76 FR 27508). This...

  2. 77 FR 63758 - Magnuson-Stevens Act Provisions; Fisheries Off West Coast States; Biennial Specifications and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-17

    ... at the Office of the Federal Register's Web site at http://www.gpo.gov/fdsys/search/home.action... specifications and management measures for most species of the Pacific Coast groundfish fishery (75 FR 67810... species of the Pacific Coast Groundfish Fishery was published on May 11, 2011 (76 FR 27508). This...

  3. 78 FR 72586 - Magnuson-Stevens Act Provisions; Fisheries off West Coast States; Biennial Specifications and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-03

    ... specifications and management measures for most species of the Pacific Coast groundfish ] fishery (77 FR 67974... species of the Pacific Coast Groundfish Fishery was published on January 3, 2013 (78 FR 580). The Council.... had a large projected underage compared to their harvest target, the Council recommended an...

  4. Higher Education as an Emerging Strategy for Actualising the Vision 2020 of the Economic Community of West African States (ECOWAS)

    ERIC Educational Resources Information Center

    Biao, Idowu

    2009-01-01

    The Economic Community of West African States (ECOWAS) has just rolled out a document spelling out five major social, economic and environmental goals it wishes to achieve by 2020. These goals are lofty indeed but they can be achieved only with reliance on not only an enlightened citizenry but on 40% of the population that should have received…

  5. Higher Education as an Emerging Strategy for Actualising the Vision 2020 of the Economic Community of West African States (ECOWAS)

    ERIC Educational Resources Information Center

    Biao, Idowu

    2011-01-01

    The Economic Community of West African States (ECOWAS) has just rolled out a document spelling out five major social, economic and environmental goals it wishes to achieve by 2020. These goals are lofty indeed but they can be achieved only with reliance on not only an enlightened citizenry but on 40% of the population that should have received…

  6. Evidence of common signatures of selection in the genomes of West African cattle and the Yoruba human population

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In 1954, Allison found that the sickle-cell anemia mutation in the beta hemoglobin gene was highly prevalent in West African people because it is protective against malaria, so carriers would thrive and leave offspring in spite of the genetic disease. This is one of the earliest evidences of an envi...

  7. The Impact of Desert Dust Aerosol Radiative Forcing on Global and West African Precipitation

    NASA Astrophysics Data System (ADS)

    Jordan, A.; Zaitchik, B. F.; Gnanadesikan, A.; Dezfuli, A. K.

    2015-12-01

    Desert dust aerosols exert a radiative forcing on the atmosphere, influencing atmospheric temperature structure and modifying radiative fluxes at the top of the atmosphere (TOA) and surface. As dust aerosols perturb radiative fluxes, the atmosphere responds by altering both energy and moisture dynamics, with potentially significant impacts on regional and global precipitation. Global Climate Model (GCM) experiments designed to characterize these processes have yielded a wide range of results, owing to both the complex nature of the system and diverse differences across models. Most model results show a general decrease in global precipitation, but regional results vary. Here, we compare simulations from GFDL's CM2Mc GCM with multiple other model experiments from the literature in order to investigate mechanisms of radiative impact and reasons for GCM differences on a global and regional scale. We focus on West Africa, a region of high interannual rainfall variability that is a source of dust and that neighbors major Sahara Desert dust sources. As such, changes in West African climate due to radiative forcing of desert dust aerosol have serious implications for desertification feedbacks. Our CM2Mc results show net cooling of the planet at TOA and surface, net warming of the atmosphere, and significant increases in precipitation over West Africa during the summer rainy season. These results differ from some previous GCM studies, prompting comparative analysis of desert dust parameters across models. This presentation will offer quantitative analysis of differences in dust aerosol parameters, aerosol optical properties, and overall particle burden across GCMs, and will characterize the contribution of model differences to the uncertainty of forcing and climate response affecting West Africa.

  8. Comparative self-concept variances of school children in two English-speaking West African nations.

    PubMed

    Alawiye, O; Alawiye, C Z; Thomas, J I

    1990-03-01

    This study examined the self-concepts of elementary school children in Grades 2, 4, 6, and 8, from two West African nations, Ghana and Gambia. Measures of self-concept in the areas of physical maturity, peer relations, academic success, and school adaptiveness were obtained from 195 Ghanaian and 156 Gambian students. The mean scores of the students were subjected to a series of three-way analyses of variance (ANOVAs). The independent variables were sex, grade level, and nationality. The overall analyses revealed grade level as the most potent variable in the self-concept development of both groups, whereas the sex variable indicated interaction with grade level only in Gambian children. The self-esteem of the children in both nations in the areas of physical maturity, peer relations, and academic success was relatively high and stable. Self-concept developmental patterns showed differences across grade levels in the four self-concept areas being tested.

  9. On the Mathematical Analysis of Ebola Hemorrhagic Fever: Deathly Infection Disease in West African Countries

    PubMed Central

    Atangana, Abdon; Goufo, Emile Franc Doungmo

    2014-01-01

    For a given West African country, we constructed a model describing the spread of the deathly disease called Ebola hemorrhagic fever. The model was first constructed using the classical derivative and then converted to the generalized version using the beta-derivative. We studied in detail the endemic equilibrium points and provided the Eigen values associated using the Jacobian method. We furthered our investigation by solving the model numerically using an iteration method. The simulations were done in terms of time and beta. The study showed that, for small portion of infected individuals, the whole country could die out in a very short period of time in case there is not good prevention. PMID:25688348

  10. Studies on the intestinal parasites in African patients in Owamboland, South West Africa.

    PubMed

    Kyrönseppä, H J; Goldsmid, J M

    1978-01-01

    The paper gives the results of a survey of intestinal parasites among 501 in-patients drawn from four mission hospitals in Owambo and Kavango in northern South West Africa. Most of the patients (90%) were examined twice by the formol-ether concentration method, while the remaining 10% had one stool specimen examined. 10 species of helminths and 3 species of potentially-pathogenic protozoa were recorded--Necator americanus, Strongyloides stercoralis, Strongyloides fuelleborni, Hymenolepis nana, Taenia saginata, Trichuris trichura, Enterobius vermicularis, Fasciola gigantica, Schistosoma mansoni and S. haematobium, and Entamoeba histolytica, Giardia lamblia and Balantidium coli. The loads of Necator americanus were recorded in a few cases. The results are compared with those of some other Central and Southern African countries. 96 blood smears were examined for filaria and 46 patients were tested for bilharzia using the bilharzial skin test. Both groups gave only negative results. PMID:635971

  11. Morphological variation in the hydromedusa genus Polyorchis on the west coast of North America

    SciTech Connect

    Rees, John T.; Larson, R. J.

    1980-11-01

    Morphological variation in the hydromedusan genus Polyorchis on the west coast of North American is analyzed in relation to gonad number, tentacle number, and radial canal diverticula number relative to the height of the bell. In specimens of Polyorchis examined, it is concluded that P. penicillatus (Eschscholtz, 1829) is highly variable morphologically over its known geographic range from Alaska to Baja California. P. montereyensis Skogsberg, 1948 is considered a synonym of P. penicillatus, while P. haplus Skogsberg. 1948, is retained as a valid species.

  12. Desertification and a shift of forest species in the West African Sahel

    USGS Publications Warehouse

    Gonzalez, P.

    2001-01-01

    Original field data show that forest species richness and tree density in the West African Sahel declined in the last half of the 20th century. Average forest species richness of areas of 4 km2 in Northwest Senegal fell from 64 ?? 2 species ca 1945 to 43 ?? 2 species in 1993, a decrease significant at p < 0.001. Densities of trees of height ???3 m declined from 10 ?? 0.3 trees ha-1 in 1954 to 7.8 ?? 0.3 trees ha-1 in 1989, also significant at p < 0.001. Standing wood biomass fell 2.1 t ha-1 in the period 1956-1993, releasing CO2 at a rate of 60 kgC person-1 yr-1. These changes have shifted vegetation zones toward areas of higher rainfall at an average rate of 500 to 600 m yr-1. Arid Sahel species have expanded in the north, tracking a concomitant retraction of mesic Sudan and Guinean species to the south. Multivariate analyses identify latitude and longitude, proxies for rainfall and temperature, as the most significant factors explaining tree and shrub distribution. The changes also decreased human carrying capacity to below actual population densities. The rural population of 45 people km-2 exceeded the 1993 carrying capacity, for firewood from shrubs, of 13 people km-2 (range 1 to 21 people km-2). As an adaptation strategy, ecological and socioeconomic factors favor the natural regeneration of local species over the massive plantation of exotic species. Natural regeneration is a traditional practice in which farmers select small field trees that they wish to raise to maturity, protect them, and prune them to promote rapid growth of the apical meristem. The results of this research provide evidence for desertification in the West African Sahel. These documented impacts of desertification foreshadow possible future effects of climate change.

  13. KZai 02 pollen record, an insight into West African monsoon fluctuations during the Last Climatic Cycle

    NASA Astrophysics Data System (ADS)

    Dalibard, M.; Popescu, S.; Maley, J.; Suc, J.

    2012-12-01

    Climate of the circum-Atlantic intertropical zone is driven by the ocean/atmosphere dynamics in response to variations of yearly insolation. These latitudes correspond to the convergence of the Hadley cells expressed on earth surface by intense trade winds and in lower troposphere by the African easterly jet making the edges of the intertropical zone relatively dry, while humidity is concentrated near the Equator. This phenomenon generates a precipitation front, known as the InterTropical Convergence Zone (ITCZ), the oscillations of which regulate the latitudinal vegetation distribution. Pollen record of core KZai 02 (Guinea Gulf) allows high resolution reconstruction of variations of past ecosystems over Central Africa during the Last Climatic Cycle. Plant taxa recorded in pollen analyses have been clustered according to their ecological requirements and African phytogeography. Fluctuations of these groups inform on precipitation intensity and their distribution during the last 130 ka. During Glacials, an open vegetation made of Cyperaceae marshes developed in the central Zaire/Congo Basin, surrounded by savannah on borders and afromontane forests on reliefs. Composition and distribution of vegetation indicate a decrease in monsoon activity and the strengthening of the precipitation front in the center of the basin. Interglacial phases are characterized by rain forest expansion over Central Africa in response to a precipitation enhancement associated with a northward shift of the rainfall front. Replacement of afromontane forest and marsh ecosystems by savannah then lowland pioneering, warm-temperate and rain forests characterized glacial/interglacial transitions. This succession suggests the increasing influence of at least two climatic parameters: the water availability and temperature and/or CO2 fluctuation. Spectral analysis applied to vegetation groups evidences the forcing of insolation, mainly driven by precession, on the West African monsoon system. Sub

  14. Tracking cashew economically important diseases in the West African region using metagenomics.

    PubMed

    Monteiro, Filipa; Romeiras, Maria M; Figueiredo, Andreia; Sebastiana, Mónica; Baldé, Aladje; Catarino, Luís; Batista, Dora

    2015-01-01

    During the last decades, agricultural land-uses in West Africa were marked by dramatic shifts in the coverage of individual crops. Nowadays, cashew (Anacardium occidentale L.) is one of the most export-oriented horticulture crops, notably in Guinea-Bissau. Relying heavily on agriculture to increase their income, developing countries have been following a strong trend of moving on from traditional farming systems toward commercial production. Emerging infectious diseases, driven either by adaptation to local conditions or inadvertent importation of plant pathogens, are able to cause tremendous cashew production losses, with economic and social impact of which, in developing countries is often underestimated. Presently, plant genomics with metagenomics as an emergent tool, presents an enormous potential to better characterize diseases by providing extensive knowledge on plant pathogens at a large scale. In this perspective, we address metagenomics as a promising genomic tool to identify cashew fungal associated diseases as well as to discriminate the causal pathogens, aiming at obtaining tools to help design effective strategies for disease control and thus promote the sustainable production of cashew in West African Region. PMID:26175748

  15. Tracking cashew economically important diseases in the West African region using metagenomics

    PubMed Central

    Monteiro, Filipa; Romeiras, Maria M.; Figueiredo, Andreia; Sebastiana, Mónica; Baldé, Aladje; Catarino, Luís; Batista, Dora

    2015-01-01

    During the last decades, agricultural land-uses in West Africa were marked by dramatic shifts in the coverage of individual crops. Nowadays, cashew (Anacardium occidentale L.) is one of the most export-oriented horticulture crops, notably in Guinea-Bissau. Relying heavily on agriculture to increase their income, developing countries have been following a strong trend of moving on from traditional farming systems toward commercial production. Emerging infectious diseases, driven either by adaptation to local conditions or inadvertent importation of plant pathogens, are able to cause tremendous cashew production losses, with economic and social impact of which, in developing countries is often underestimated. Presently, plant genomics with metagenomics as an emergent tool, presents an enormous potential to better characterize diseases by providing extensive knowledge on plant pathogens at a large scale. In this perspective, we address metagenomics as a promising genomic tool to identify cashew fungal associated diseases as well as to discriminate the causal pathogens, aiming at obtaining tools to help design effective strategies for disease control and thus promote the sustainable production of cashew in West African Region. PMID:26175748

  16. [Health consequences of the tobacco epidemic in West African French-speaking countries and current tobacco control].

    PubMed

    da Costa e Silva, Vera Luiza

    2005-01-01

    The burden of disease due to tobacco for each country will depend on the prevalence of tobacco use and the duration of the epidemic. Given that the tobacco epidemic in West African Francophone countries is relatively recent, the burden of disease due to tobacco use is currently low. However, tobacco related burden of disease in Francophone West African countries is increasing as the number of smokers continues to increase and the population has been smoking for a longer period of time. If the current trends continue, West African countries will be suffering the massive consequences of tobacco use in two or three decades. Apart from the classical health consequences of tobacco consumption such as certain types of cancer and cardiovascular diseases, there are some conditions of special importance in low income African countries such as the increased risk of tuberculosis infection and mortality amongst smokers, low birth weight for babies of smoking mothers, and tobacco consumption associated malnutrition especially amongst women. Furthermore, developing countries, with inadequate resources and other important health issues, cannot afford the costs of the chronic degenerating conditions caused by tobacco use, as these are very expensive to treat. Tobacco control in Francophone African countries is still deficient Human and financial resources which are often scarce in West African countries are dedicated to other health issues since tobacco is normally not amongst the public health priorities. Legislation in Francophone African countries is limited and not adequately enforced. A major reason for governments' inaction on tobacco is their fear of creating unemployment and loss of revenue from tobacco taxes. This fear is derived mainly from the arguments of the tobacco industry. Apart from lobbying governments, the tobacco industry uses all kinds of strategies to market their products in these countries and faces practically no barriers to their business in these

  17. Equilibrium Beach Profiles on the East and West U.S. Coasts

    NASA Astrophysics Data System (ADS)

    Ludka, B. C.; Guza, R. T.; McNinch, J. E.; O'Reilly, W.

    2012-12-01

    Beach elevation change observations from the United States west and east coasts are used to identify statistically the dominant cross-shore patterns in sand level fluctuations, and these changes are related to equilibrium beach profile concepts. Three to seven years of observations at four beaches in Southern California include monthly surveys of the subaerial (near MSL) beach, and quarterly surveys from the backbeach to about 8m depth. At Duck, North Carolina, observations include 31 years of monthly surveys from the dunes to about 8m depth. On the Southern California beaches, the dominant seasonal pattern is subaerial erosion in winter and accretion in summer. Seasonal fluctuations of 3m in shoreline vertical sand levels, and 50m in subaerial beach width, are not uncommon. The sand eroded from the shoreline in winter is stored in an offshore sand bar and returns to the beach face in summer. Wave conditions in Southern California also vary seasonally, with energetic waves arriving from the north in winter, and lower energy, longer period southerly swell arriving in summer. A spectral refraction model, initialized with a regional network of directional wave buoys, is used to estimate hourly wave conditions, in 10m water depth. Using an equilibrium hypothesis, that the shoreline (defined as the cross-shore location of the MSL contour) change rate depends on the wave energy and the wave energy disequilibrium, Yates (2009) modeled the time-varying shoreline location at several Southern California beaches with significant skill. The four free model parameters were calibrated to fit observations. Following Yates (2009), we extend the equilibrium shoreline model to include the horizontal displacement of other elevation contours. At the Southern California sites, the modeled contour translation depends on the incident wave energy, the present contour configuration, and observation-based estimates of the contour behavior (based on EOF spatial amplitudes). At Duck, seasonal

  18. Feedback of observed interannual vegetation change: a regional climate model analysis for the West African monsoon

    NASA Astrophysics Data System (ADS)

    Klein, Cornelia; Bliefernicht, Jan; Heinzeller, Dominikus; Gessner, Ursula; Klein, Igor; Kunstmann, Harald

    2016-06-01

    West Africa is a hot spot region for land-atmosphere coupling where atmospheric conditions and convective rainfall can strongly depend on surface characteristics. To investigate the effect of natural interannual vegetation changes on the West African monsoon precipitation, we implement satellite-derived dynamical datasets for vegetation fraction (VF), albedo and leaf area index into the Weather Research and Forecasting model. Two sets of 4-member ensembles with dynamic and static land surface description are used to extract vegetation-related changes in the interannual difference between August-September 2009 and 2010. The observed vegetation patterns retain a significant long-term memory of preceding rainfall patterns of at least 2 months. The interannual vegetation changes exhibit the strongest effect on latent heat fluxes and associated surface temperatures. We find a decrease (increase) of rainy hours over regions with higher (lower) VF during the day and the opposite during the night. The probability that maximum precipitation is shifted to nighttime (daytime) over higher (lower) VF is 12 % higher than by chance. We attribute this behaviour to horizontal circulations driven by differential heating. Over more vegetated regions, the divergence of moist air together with lower sensible heat fluxes hinders the initiation of deep convection during the day. During the night, mature convective systems cause an increase in the number of rainy hours over these regions. We identify this feedback in both water- and energy-limited regions of West Africa. The inclusion of observed dynamical surface information improved the spatial distribution of modelled rainfall in the Sahel with respect to observations, illustrating the potential of satellite data as a boundary constraint for atmospheric models.

  19. Incidence of pregnancy following antiretroviral therapy initiation and associated factors in eight West African countries

    PubMed Central

    Burgos-Soto, Juan; Balestre, Eric; Minga, Albert; Ajayi, Samuel; Sawadogo, Adrien; Zannou, Marcel D.; Leroy, Valériane; Ekouevi, Didier K.; Dabis, François; Becquet, Renaud

    2014-01-01

    Introduction This study aimed at estimating the incidence of pregnancy after antiretroviral therapy (ART) initiation in eight West African countries over a 10-year period. Methods A retrospective analysis was conducted within the international database of the IeDEA West Africa Collaboration. All HIV-infected women aged <50 years and starting ART for their own health between 1998 and 2011 were eligible. Pregnancy after ART initiation was the main outcome and was based on clinical reporting. Poisson regression analysis accounting for country heterogeneity was computed to estimate first pregnancy incidence post-ART and to identify its associated factors. Pregnancy incidence rate ratios were adjusted on country, baseline CD4 count and clinical stage, haemoglobin, age, first ART regimen and calendar year. Results Overall 29,425 HIV-infected women aged 33 years in median [Inter Quartile Range: 28–38] contributed for 84,870 women-years of follow-up to this analysis. The crude incidence of first pregnancy (2,304 events) was 2.9 per 100 women-years [95% confidence interval [CI]: 2.7–3.0], the highest rate being reported among women aged 25–29 years: 4.7 per 100 women-years; 95% CI: 4.3–5.1. The overall Kaplan-Meier probability of pregnancy occurrence by the fourth year on ART was 10.9% (95% CI: 10.4–11.4) and as high as 28.4% (95% CI: 26.3–30.6) among women aged 20–29 years at ART initiation. Conclusion The rate of pregnancy occurrence after ART initiation among HIV-infected women living in the West Africa region was high. Family planning services tailored to procreation needs should be provided to all HIV-infected women initiating ART and health consequences carefully monitored in this part of the world. PMID:25216079

  20. Contrasting conditions of surface water balance in wet years and dry years as a possible land surface-atmosphere feedback mechanism in the West African Sahel

    NASA Technical Reports Server (NTRS)

    Lare, A. R.; Nicholson, S. E.

    1994-01-01

    The climate of West Africa, in particular the Sahel, is characterized by multiyear persistence of anomalously wet or dry conditions. Its Southern Hemisphere counterpart, the Kalahari, lacks the persistence that is evident in the Sahel even though both regions are subject to similar large-scale forcing. It has been suggested that land surface-atmosphere feedback contributes to this persistence and to the severity of drought. In this study, surface energy and water balance are quantified for nine stations along a latitudinal transect that extends from the Sahara to the Guinea coast. In the wetter regions of West Africa, the difference between wet and dry years is primarily reflected in the magnitude of runoff. For the Sahel and drier locations, evapotranspiration and soil moisture are more sensitive to rainfall anomalies. The increase in evapotranspiration, and hence latent heating, over the Sahel in wet years alters the thermal structure and gradients of the overlying atmosphere and thus the strength of the African easterly jet (AEJ) at 700 mb. The difference between dry and wet Augusts corresponds to a decrease in magnitude of the AEJ at 15 deg N on the order of 2.6 m/s, which is consistent with previous studies of observed winds. Spatial patterns were also developed for surface water balance parameters for both West Africa and southern Africa. Over southern Africa, the patterns are not as spatially homogeneous as those over West Africa and are lower in magnitude, thus supporting the suggestion that the persistence of rainfall anomalies in the Sahel might be due, at least in part, to land-atmosphere feedback, and that the absence of such persistence in the Kalahari is a consequence of less significant changes in surface water and energy balance.

  1. The West African Monsoon: variability and teleconnection with ENSO during the years 1948-57

    NASA Astrophysics Data System (ADS)

    Stickler, Alexander; Brönnimann, Stefan

    2010-05-01

    The intensity of the West African Monsoon (WAM) has been shown to be influenced by different factors. Most important for the existence of the monsoon system is the land-sea thermal contrast between the North African landmass and the Gulf of Guinea. ENSO plays an important role for its interannual variability via an atmospheric teleconnection bridging the Pacific and Atlantic oceanic basins and favouring either descent/weak low-level monsoon flow or ascent/strong low-level monsoon flow over tropical West Africa. Most published studies on the WAM variability are based on reanalysis datasets. However, while reproducing quite well the interannual variability, reanalysis products have been found to contain major biases in certain tropical regions before 1968. These lead to an unrealistic low frequency behaviour and might be explained by the lack of observations assimilated into the reanalyses, as is the case e.g. for tropical Africa where only the much sparser radiosonde data have been assimilated into the NCEP/NCAR Reanalysis (NNR). Here we present an analysis of the interannual WAM variability and its teleconnection with ENSO for the years 1948-57 which is not based on a reanalysis, but on early pilot balloon observational wind data from the Comprehensive Historical Upper Air Network (CHUAN). We have examined wind data from all 36 stations located in the domain (10°S-30°N, 20°W-20°E) on 5 levels up to the mid troposphere (corresponding roughly to the 925, 850, 700, 600 and 500 hPa pressure levels). This analysis shows that 7 subregions can be defined which are characterised by similar vertical wind profiles as well as seasonality: the NW (Mauritania, northern Senegal), the SW (southern Senegal to coastal Guinea), central sub-Saharan West Africa (SSWA, from interior Guinea in the W to coastal Cameroon and southern Niger in the E), central and eastern Niger, western Chad, the western Central African Republic, and the southern coastal regions east of the Gulf of

  2. Renin angiotensinogen system gene polymorphisms and essential hypertension among people of West African descent: a systematic review.

    PubMed

    Reiter, L M; Christensen, D L; Gjesing, A P

    2016-08-01

    This systematic review investigates the high level of hypertension found among urban dwellers in West Africa and in the West African Diaspora in the Americas in relation to variants within the genes encoding the renin angiotensinogen system. For comparison, the results from the Caucasian populations are reviewed as well. Through a PubMed search, 1252 articles were identified and 28 eligible articles assessed in detail of which 13 included a Caucasian population. The results suggest that among the people of West African descent and among the people of Caucasian descent, hypertension is partly related to a number of single nucleotide polymorphisms (SNPs) and haplotypes in the renin gene, the angiotensinogen gene, the angiotensinogen I-converting enzyme gene and the angiotensinogen II type 1 receptor gene. Concordance between these two populations was found for some SNPs. However, for others, it was found that the SNPs associating with hypertension and the disease allele frequencies differed between these populations. Understanding the importance of these variants in a modern life setting may assist our understanding of the increased risk of developing hypertension among West Africans. Because of inconsistency in the results, low statistical power and methodological differences between studies, these results can only be taken as indicative of an association.

  3. Upwelling of Acidified Water: Not Just an Issue for Shellfish Hatcheries on the West Coast of the US

    NASA Astrophysics Data System (ADS)

    Poach, M.; Munroe, D.; Abrahamsen, I.

    2014-12-01

    Periodic upwelling events are known to occur off the coast of New Jersey during the summer. As with upwelling off the US West Coast, these events can transport acidified water to the surface and shoreward. To determine if upwelling events have the potential to impact shellfish hatcheries in New Jersey, a monitoring study was conducted at the Aquaculture Innovation Center (AIC) of Rutgers University. The AIC is an important hatchery supporting the New Jersey oyster aquaculture industry through the production of disease resistant seed oysters. Starting in June of 2014, temperature, salinity, dissolved oxygen and pH were continuously monitored at the AIC's intake pipe. Periodic grab samples were also collected at the intake and at locations within the facility. Grab samples were preserved and analyzed for pH and dissolved inorganic carbon (DIC). DIC and pH were used to calculate the aragonite saturation state of the sampled water. During an upwelling event in early July a drop in pH was measured at the intake. Grab samples showed that water of lower pH and aragonite saturation was entering the facility. These results show that hatcheries along the NJ coast need to be aware that upwelling events may bring conditions detrimental for shellfish production.

  4. Assessment of the petroleum, coal, and geothermal resources of the Economic Community of West African States (ECOWAS) region

    USGS Publications Warehouse

    Mattick, R. E.

    1982-01-01

    Approximately 85 percent of the land area of the ECOWAS (Economic Community of West African States) region is covered by basement rocks (igneous and highly metamorphosed rocks) or relatively thin layers of Paleozoic, Upper Precambrian, and 'Continental Intercalaire? sedimentary rocks. These areas have little or no petroleum potential. Areas of the ECOWAS region that have potential for petroleum production or potential for increased petroleum production include the narrow belt of sedimentary rocks that stretches along the continental margin from Mauritania to Nigeria and the Niger Delta and the Benue depression. The Senegal Basin, located on the continental margin of Mauritania, Senegal, Gambia, Guinea Bissau, and Guinea, has been intensely explored by the oil industry and most of the larger structures onshore and on the shelf probably have been tested by drilling with little or no resulting commercial production. Unless basic ideas pertaining to the petroleum geology of the Senegal Basin are revised, future discoveries are expected to be limited to small fields overlooked by industry at a time when petroleum prices were low. On the continental shelf of Sierra Leone and the continental shelf of northeast and central Liberia, the sedimentary rocks are relatively thin, and industry has shown little interest in the area. On the continental rise of these countries, however, the sedimentary section, deposited in a complex fault-block system, increases in thickness. A renewal of industry interest in this deep-water area will probably follow further development of deep-water production technology. A recent oil discovery on the continental slope off the Ivory Coast is expected to spur further exploration offshore of southeastern Liberia, Ivory Coast, Ghana, Togo, and Benin. This relatively unexplored area in the Gulf of Guinea has good possibilities .for the discovery of giant oil fields. Nigeria's oil development from the Niger Delta may have peaked, as 13 of 14 giant oil

  5. West African monsoon decadal variability and surface-related forcings: second West African Monsoon Modeling and Evaluation Project Experiment (WAMME II)

    NASA Astrophysics Data System (ADS)

    Xue, Yongkang; De Sales, Fernando; Lau, William K.-M.; Boone, Aaron; Kim, Kyu-Myong; Mechoso, Carlos R.; Wang, Guiling; Kucharski, Fred; Schiro, Kathleen; Hosaka, Masahiro; Li, Suosuo; Druyan, Leonard M.; Sanda, Ibrah Seidou; Thiaw, Wassila; Zeng, Ning; Comer, Ruth E.; Lim, Young-Kwon; Mahanama, Sarith; Song, Guoqiong; Gu, Yu; Hagos, Samson M.; Chin, Mian; Schubert, Siegfried; Dirmeyer, Paul; Ruby Leung, L.; Kalnay, Eugenia; Kitoh, Akio; Lu, Cheng-Hsuan; Mahowald, Natalie M.; Zhang, Zhengqiu

    2016-06-01

    The second West African Monsoon Modeling and Evaluation Project Experiment (WAMME II) is designed to improve understanding of the possible roles and feedbacks of sea surface temperature (SST), land use land cover change (LULCC), and aerosols forcings in the Sahel climate system at seasonal to decadal scales. The project's strategy is to apply prescribed observationally based anomaly forcing, i.e., "idealized but realistic" forcing, in simulations by climate models. The goal is to assess these forcings' effects in producing/amplifying seasonal and decadal climate variability in the Sahel between the 1950s and the 1980s, which is selected to characterize the great drought period of the last century. This is the first multi-model experiment specifically designed to simultaneously evaluate such relative contributions. The WAMME II models have consistently demonstrated that SST forcing is a major contributor to the twentieth century Sahel drought. Under the influence of the maximum possible SST forcing, the ensemble mean of WAMME II models can produce up to 60 % of the precipitation difference during the period. The present paper also addresses the role of SSTs in triggering and maintaining the Sahel drought. In this regard, the consensus of WAMME II models is that both Indian and Pacific Ocean SSTs greatly contributed to the drought, with the former producing an anomalous displacement of the Intertropical Convergence Zone before the WAM onset, and the latter mainly contributes to the summer WAM drought. The WAMME II models also show that the impact of LULCC forcing on the Sahel climate system is weaker than that of SST forcing, but still of first order magnitude. According to the results, under LULCC forcing the ensemble mean of WAMME II models can produces about 40 % of the precipitation difference between the 1980s and the 1950s. The role of land surface processes in responding to and amplifying the drought is also identified. The results suggest that catastrophic

  6. 78 FR 23135 - Safety Zone; Blue Water Resort & Casino West Coast Nationals; Parker, AZ

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-18

    ... visit the Docket Management Facility in Room W12-140 on the ground floor of the Department of... rule, call or email Petty Officer Bryan Gollogly, Waterways Management, U.S. Coast Guard Sector San.... SUPPLEMENTARY INFORMATION: Table of Acronyms DHS Department of Homeland Security FR Federal Register NPRM...

  7. 77 FR 24634 - Magnuson-Stevens Act Provisions; Fisheries off West Coast States; Biennial Specifications and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-25

    ... management measures for most species of the Pacific Coast groundfish fishery (75 FR 67810). The final rule to... Groundfish Fishery was published on May 11, 2011 (76 FR 27508). This final rule was subsequently amended by several inseason actions (76 FR 39313, 76 FR 67092, 76 FR 79122, 77 FR 12503, 77 FR 22679). On...

  8. Draft Genome Sequence of Halomonas hydrothermalis MTCC 5445, Isolated from the West Coast of India.

    PubMed

    Bharadwaj Sv, Vamsi; Shrivastav, Anupama; Dubey, Sonam; Ghosh, Tonmoy; Paliwal, Chetan; Maurya, Rahulkumar; Mishra, Sandhya

    2015-01-01

    We announce here the draft genome sequence of Halomonas hydrothermalis MTCC 5445, a halophilic bacterium of the class Gammaproteobacteria. It was isolated from the sea coast of Aadri, Veraval, Gujarat, India. Its genome contains genes for polyhydroxybutyrate (PHB), a biodegradable polymer that can be used as a substitute for petroleum plastics. PMID:25593258

  9. 75 FR 932 - Fisheries Off West Coast States; Coastal Pelagic Species Fisheries; Annual Specifications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-07

    ... in the U.S. exclusive economic zone (EEZ) off the Pacific coast for the fishing season of July 1... Coastal Pelagic Species (CPS) Fishery Management Plan (FMP) and establishes allowable harvest levels for... public comments (74 FR 4845). One comment was received, which was in support of the proposed...

  10. 77 FR 73005 - Fisheries Off West Coast States; Coastal Pelagic Species Fisheries; Annual Specifications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-07

    ...NMFS proposes to implement the annual catch limit (ACL), harvest guideline (HG), annual catch target (ACT) and associated annual reference points for Pacific mackerel in the U.S. exclusive economic zone (EEZ) off the Pacific coast for the fishing season of July 1, 2012, through June 30, 2013. This rule is proposed according to the Coastal Pelagic Species (CPS) Fishery Management Plan (FMP).......

  11. 78 FR 51097 - Fisheries Off West Coast States; Coastal Pelagic Species Fisheries; Closure

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-20

    ...NMFS is prohibiting directed fishing for Pacific sardine off the coasts of Washington, Oregon and California. This action is necessary because the directed harvest allocation total for the second seasonal period (July 1-September 14) is projected to be reached by the effective date of this rule. From the effective date of this rule until September 15, 2013, Pacific sardine may be harvested......

  12. 78 FR 26277 - Magnuson-Stevens Act Provisions; Fisheries Off West Coast States; Biennial Specifications and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-06

    ... the Office of the Federal Register's Web site at http://www.gpo.gov/fdsys/search/home.action... for most species of the Pacific Coast Groundfish Fishery was published on January 3, 2013 (78 FR 580..., Indian Fisheries. Dated: May 1, 2013. Kara Meckley, Acting Deputy Director, Office of...

  13. The colonial ascidian Didemnum sp. A: current distribution, basic biology and potential threat to marine communities of the northeast and west coasts of North America

    USGS Publications Warehouse

    Bullard, S.G.; Lambert, G.; Carman, M.R.; Byrnes, J.; Whitlatch, R.B.; Ruiz, G.; Miller, R.J.; Harris, L.; Valentine, P.C.; Collie, J.S.; Pederson, J.; McNaught, D.C.; Cohen, A.N.; Asch, R.G.; Dijkstra, J.; Heinonen, K.

    2007-01-01

    Didemnum sp. A is a colonial ascidian with rapidly expanding populations on the east and west coasts of North America. The origin of Didemum sp. A is unknown. Populations were first observed on the northeast coast of the U.S. in the late 1980s and on the west coast during the 1990s. It is currently undergoing a massive population explosion and is now a dominant member of many subtidal communities on both coasts. To determine Didemnum sp. A's current distribution, we conducted surveys from Maine to Virginia on the east coast and from British Columbia to southern California on the west coast of the U.S. between 1998 and 2005. In nearshore locations Didemnum sp. A currently ranges from Eastport, Maine to Shinnecock Bay, New York on the east coast. On the west coast it has been recorded from Humboldt Bay to Port San Luis in California, several sites in Puget Sound, Washington, including a heavily fouled mussel culture facility, and several sites in southwestern British Columbia on and adjacent to oyster and mussel farms. The species also occurs at deeper subtidal sites (up to 81 m) off New England, including Georges, Stellwagen and Tillies Banks. On Georges Bank numerous sites within a 230 km2 area are 50–90% covered by Didemnum sp. A; large colonies cement the pebble gravel into nearly solid mats that may smother infaunal organisms. These observations suggest that Didemnum sp. A has the potential to alter marine communities and affect economically important activities such as fishing and aquaculture.

  14. The Ebola threat: China's response to the West African epidemic and national development of prevention and control policies and infrastructure.

    PubMed

    Fan, Hao-Jun; Gao, Hong-Wei; Ding, Hui; Zhang, Bi-Ke; Hou, Shi-Ke

    2015-02-01

    There is growing concern in West Africa about the spread of the Ebola hemorrhagic fever virus. With the increasing global public health risk, a coordinated international response is necessary. The Chinese government is prepared to work in collaboration with West African countries to assist in the containment and control of the epidemic through the contribution of medical expertise and mobile laboratory testing teams. Nationally, China is implementing prevention programs in major cities and provinces, the distribution of Ebola test kits, and the deployment of a new national Ebola research laboratory.

  15. The Ebola threat: China's response to the West African epidemic and national development of prevention and control policies and infrastructure.

    PubMed

    Fan, Hao-Jun; Gao, Hong-Wei; Ding, Hui; Zhang, Bi-Ke; Hou, Shi-Ke

    2015-02-01

    There is growing concern in West Africa about the spread of the Ebola hemorrhagic fever virus. With the increasing global public health risk, a coordinated international response is necessary. The Chinese government is prepared to work in collaboration with West African countries to assist in the containment and control of the epidemic through the contribution of medical expertise and mobile laboratory testing teams. Nationally, China is implementing prevention programs in major cities and provinces, the distribution of Ebola test kits, and the deployment of a new national Ebola research laboratory. PMID:25563862

  16. The Mid-Holocene West African Monsoon strength modulated by Saharan dust and vegetation

    NASA Astrophysics Data System (ADS)

    Pausata, F. S. R.; Messori, G.; Zhang, Q.

    2015-12-01

    The West African Monsoon (WAM) is crucial for the socio-economic stability of millions of people living in the Sahel. Severe droughts have ravaged the region in the last three decades of the 20th century, highlighting the need for a better understanding of the WAM dynamics. One of the most dramatic changes in the WAM occurred between 15,000-5,000 years BP, when increased summer precipitation led to the so-called "Green Sahara" and to a reduction in dust emissions from the region. Previous studies have shown that variations in vegetation and soil type can have major impacts on precipitation. However, model simulations are still unable to fully reproduce the intensification and geographical expansion of the African monsoon during that period, even when vegetation over the Sahara is simulated. Here, we use a fully coupled simulation for 6000 years BP in which prescribed Saharan vegetation and dust concentrations are changed in turn. A close agreement with proxy records is obtained only when both Saharan vegetation and dust decrease are taken into account (Fig. 1). The dust reduction extends the monsoon's northern limit further than the vegetation-change case only (Fig. 2), by strengthening vegetation-albedo feedbacks and driving a deeper Saharan Heat Low. The dust reduction under vegetated Sahara conditions leads to a northward shift of the WAM extension that is about twice as large as the shift due to the changes in orbital forcing alone. We therefore conclude that accounting for changes in Saharan dust loadings is essential for improving model simulations of the MH WAM. The role of dust is also relevant when looking into the future, since Saharan dust emission may decrease owing to both direct and indirect anthropogenic impacts on land cover.

  17. West African Monsoon dynamics in idealized simulations: the competitive roles of SST warming and CO2

    NASA Astrophysics Data System (ADS)

    Gaetani, Marco; Flamant, Cyrille; Hourdin, Frederic; Bastin, Sophie; Braconnot, Pascale; Bony, Sandrine

    2015-04-01

    The West African Monsoon (WAM) is affected by large climate variability at different timescales, from interannual to multidecadal, with strong environmental and socio-economic impacts associated to climate-related rainfall variability, especially in the Sahelian belt. State-of-the-art coupled climate models still show poor ability in correctly simulating the WAM past variability and also a large spread is observed in future climate projections. In this work, the July-to-September (JAS) WAM variability in the period 1979-2008 is studied in AMIP-like simulations (SST-forced) from CMIP5. The individual roles of global SST warming and CO2 concentration increasing are investigated through idealized experiments simulating a 4K warmer SST and a 4x CO2 concentration, respectively. Results show a dry response in Sahel to SST warming, with dryer conditions over western Sahel. On the contrary, wet conditions are observed when CO2 is increased, with the strongest response over central-eastern Sahel. The precipitation changes are associated to modifications in the regional atmospheric circulation: dry (wet) conditions are associated with reduced (increased) convergence in the lower troposphere, a southward (northward) shift of the African Easterly Jet, and a weaker (stronger) Tropical Easterly Jet. The co-variability between global SST and WAM precipitation is also investigated, highlighting a reorganization of the main co-variability modes. Namely, in the 4xCO2 simulation the influence of Tropical Pacific is dominant, while it is reduced in the 4K simulation, which also shows an increased coupling with the eastern Pacific and the Indian Ocean. The above results suggest a competitive action of SST warming and CO2 increasing on the WAM climate variability, with opposite effects on precipitation. The combination of the observed positive and negative response in precipitation, with wet conditions in central-eastern Sahel and dry conditions in western Sahel, is consistent with the

  18. The first endemic West African vertebrate family – a new anuran family highlighting the uniqueness of the Upper Guinean biodiversity hotspot

    PubMed Central

    2014-01-01

    Background Higher-level systematics in amphibians is relatively stable. However, recent phylogenetic studies of African torrent-frogs have uncovered high divergence in these phenotypically and ecologically similar frogs, in particular between West African torrent-frogs versus Central (Petropedetes) and East African (Arthroleptides and Ericabatrachus) lineages. Because of the considerable molecular divergence, and external morphology of the single West African torrent-frog species a new genus was erected (Odontobatrachus). In this study we aim to clarify the systematic position of West African torrent-frogs (Odontobatrachus). We determine the relationships of torrent-frogs using a multi-locus, nuclear and mitochondrial, dataset and include genera of all African and Asian ranoid families. Using micro-tomographic scanning we examine osteology and external morphological features of West African torrent-frogs to compare them with other ranoids. Results Our analyses reveal Petropedetidae (Arthroleptides, Ericabatrachus, Petropedetes) as the sister taxon of the Pyxicephalidae. The phylogenetic position of Odontobatrachus is clearly outside Petropedetidae, and not closely related to any other ranoid family. According to our time-tree estimation Odontobatrachus has been separated from other frog lineages since the Cretaceous (90.1 Ma; confidence interval: 84.2-97.1 Ma). Along with this molecular evidence, osteological and external diagnostic characters recognize West African torrent-frogs as distinct from other ranoids and provide strong support for the necessity of the recognition of a new family of frogs. This is the only endemic vertebrate family occurring in the Upper Guinea biodiversity hotspot. Conclusion Based on molecular and morphological distinctiveness, the West African torrent-frog Odontobatrachus natator is allocated to a newly described anuran family. The discovery of an endemic vertebrate family in West Africa highlights the Upper Guinean forests as an

  19. Optical dating of aeolian dynamism on the West African Sahelian margin

    NASA Astrophysics Data System (ADS)

    Stokes, S.; Bailey, R. M.; Fedoroff, N.; O'Marah, K. E.

    2004-04-01

    The Sahelian Margin of West Africa is widely recognised as an area of recent environmental catastrophe and human suffering arising from food shortage and land degradation associated with prolonged drought. The propensity of this region to suffer drought has been related, using environmental data collected during the period of instrumental records, to a combination of low mean annual rainfall levels and a high degree of rainfall variability which relates to sea surface temperature anomalies in the adjacent tropical Atlantic Ocean. Despite the significant environmental and human consequences of such droughts, there is a paucity of long-term environmental data for the West African Sahel. Aeolian dune reactivations in this area are a potentially highly useful environmental archive of past periods of extended drought conditions, which may have resulted in localised or widespread dune reactivation. Here we describe the initial results from an ongoing programme of research, which seeks to develop a detailed record of past dune reactivations in Mali. We find evidence for repeated Holocene dune reactivation events and a significant number of reactivations, which commenced at the time of onset of the last major drought cycle in the early 1970s. We obtain ages as young as 20-30 years for some significant dune units (thickness up to 1 m) and describe the results of experiments which test the performance of our dating exercise. We specifically test for the significance of preheat temperature on single aliquot regeneration (SAR) equivalent dose determinations and recycling ratios; neither are found vary significantly as a function of preheating. Optical dating of sand sized quartz could provide a useful tool for palaeogeographical mapping of ancient and historical dune reactivations in this region and elsewhere.

  20. Effects of high ambient temperatures on the metabolism of West African dwarf goats. II

    NASA Astrophysics Data System (ADS)

    Montsma, G.; Luiting, P.; Verstegen, M. W. A.; van der Hel, W.; Hofs, P.; Zijlker, J. W.

    1985-03-01

    32 West African dwarf goats were exposed in respiration chambers to temperature treatments of 20, 25, 30, 35, 35, 35, 30, 25, 20°C. Each treatment lasted three days. 16 goats were kept in individual pens (“I”); the others in two group pens of eight animals each (“G”). During each treatment, heat production and activity were recorded continuously over 48 hours. In addition, feed and water intake, rectal temperature, skin temperature and respiratory rate were measured during each treatment. Compared to 20°C, at 35°C rectal temperature increased from 39.0°C to 39.9°C, respiratory rate from 30 to 260 times. min-1 and skin temperature from 37.1°C to 39.5°C. Hay intake decreased by 40%; concentrates (30 g. kg-0.75. d-1) were always completely consumed. Heat production was higher for the “G” animals at 20°C and higher for the “I” animals at 35°C. These differences in heat production between the two groups were reflected in differences in rectal and skin temperature and in respiratory rate but only very slightly in differences in hay intake. Tissue insulation was 0.014 K. m2. W-1 at 30°C and 35°C and 0.022 K. m2. W-1 at 20°C. It is concluded that the reactions of these dwarf goats to high ambient temperatures are not different in principle from those of other domestic ruminants and that they do not exhibit a specific suitability or unsuitability for ambient temperatures as prevailing in West Africa.

  1. Variability of West African monsoon patterns generated by a WRF multi-physics ensemble

    NASA Astrophysics Data System (ADS)

    Klein, Cornelia; Heinzeller, Dominikus; Bliefernicht, Jan; Kunstmann, Harald

    2015-11-01

    The credibility of regional climate simulations over West Africa stands and falls with the ability to reproduce the West African monsoon (WAM) whose precipitation plays a pivotal role for people's livelihood. In this study, we simulate the WAM for the wet year 1999 with a 27-member multi-physics ensemble of the Weather Research and Forecasting (WRF) model. We investigate the inter-member differences in a process-based manner in order to extract generalizable information on the behavior of the tested cumulus (CU), microphysics (MP), and planetary boundary layer (PBL) schemes. Precipitation, temperature and atmospheric dynamics are analyzed in comparison to the Tropical Rainfall Measuring Mission (TRMM) rainfall estimates, the Global Precipitation Climatology Centre (GPCC) gridded gauge-analysis, the Global Historical Climatology Network (GHCN) gridded temperature product and the forcing data (ERA-Interim) to explore interdependencies of processes leading to a certain WAM regime. We find that MP and PBL schemes contribute most to the ensemble spread (147 mm month-1) for monsoon precipitation over the study region. Furthermore, PBL schemes have a strong influence on the movement of the WAM rainband because of their impact on the cloud fraction, that ranges from 8 to 20 % at 600 hPa during August. More low- and mid-level clouds result in less incoming radiation and a weaker monsoon. Ultimately, we identify the differing intensities of the moist Hadley-type meridional circulation that connects the monsoon winds to the Tropical Easterly Jet as the main source for inter-member differences. The ensemble spread of Sahel precipitation and associated dynamics for August 1999 is comparable to the observed inter-annual spread (1979-2010) between dry and wet years, emphasizing the strong potential impact of regional processes and the need for a careful selection of model parameterizations.

  2. Estimation of freshwater availability in the West African sub-continent using the SWAT hydrologic model

    NASA Astrophysics Data System (ADS)

    Schuol, Jürgen; Abbaspour, Karim C.; Srinivasan, Raghavan; Yang, Hong

    2008-04-01

    SummaryAccurate knowledge of freshwater availability is indispensable for water resources management at regional or national level. This information, however, has historically been very difficult to obtain because of lack of data, difficulties in the aggregation of spatial information, and problems in the quantification of distributed hydrological processes. The currently available estimates of freshwater availability by a few large international organizations such as FAO and UNESCO are often not sufficient as they only provide aggregated rough quantities of river discharge and groundwater recharge (blue water) at a national level and on a yearly basis. This paper aims to provide a procedure to improve the estimations of freshwater availability at subbasin level and monthly intervals. Applying the distributed hydrological model "Soil and Water Assessment Tool" (SWAT), the freshwater availability is quantified for a 4-million km 2 area covering some 18 countries in West Africa. The procedure includes model calibration and validation based on measured river discharges, and quantification of the uncertainty in model outputs using "Sequential Uncertainty Fitting Algorithm" (SUFI-2) The aggregated results for 11 countries are compared with two other studies. It was seen that for most countries, the estimates from the other two studies fall within our calculated prediction uncertainty ranges. The uncertainties are, in general, within reasonable ranges but larger in subbasins containing features such as dams and wetlands, or subbasins with inadequate climate or landuse information. As the modelling procedure in this study proved quite successful, its application for quantification of freshwater availability at a global scale is already underway. There are, however, two limitations in the West African model: (1) not all the components of the water balance model such as soil moisture or deep aquifer recharge could be directly calibrated because of lack of data and (2) the

  3. Impact of climate change on vegetation dynamics in a West African river basin

    NASA Astrophysics Data System (ADS)

    Sawada, Y.; Koike, T.

    2012-12-01

    Future changes in terrestrial biomass distribution under climate change will have a tremendous impact on water availability and land productivity in arid and semi-arid regions. Assessment of future change of biomass distribution in the regional or the river basin scale is strongly needed. An eco-hydrological model that fully couples a dynamic vegetation model (DVM) with a distributed biosphere hydrological model is applied to multi-model assessment of climate change impact on vegetation dynamics in a West African river basin. In addition, a distributed and auto optimization system of parameters in DVM is developed to make it possible to model a diversity of phonologies of plants by using different parameters in the different model grids. The simple carbon cycle modeling in a distributed hydrological model shows reliable accuracy in simulating the seasonal cycle of vegetation on the river basin scale. Model outputs indicate that generally, an extension of dry season duration and surface air temperature rising caused by climate change may cause a dieback of vegetation in West Africa. However, we get different seasonal and spatial changes of leaf area index and different mechanisms of the degradation when we used different general circulation models' outputs as meteorological forcing of the eco-hydrological model. Therefore, multi-model analysis like this study is important to deliver meaningful information to the society because we can discuss the uncertainties of our prediction by this methodology. This study makes it possible to discuss the impact of future change of terrestrial biomass on climate and water resources in the regional or the river basin scale although we need further sophistications of the system. Performance of the eco-hydrological model (WEB-DHM+DVM) in Volta River Basin, with basin-averaged leaf area index from model (blue solid line) and AVHRR satellite-derived product (red rectangles).

  4. Patterns of species diversity in estuarine benthic communities along teh US west coast

    EPA Science Inventory

    Estuaries in the Pacific North West (PNW) were recently classified by whether the estuary is river- or ocean-dominated, the extent of intertidal to subtidal environments, and spatial salinity patterns. We examine whether these characteristics predict patterns of soft-sediment, m...

  5. Year-round West Nile Virus Activity, Gulf Coast Region, Texas and Louisiana

    PubMed Central

    Parsons, Ray; Siirin, Marina; Randle, Yvonne; Sargent, Chris; Guzman, Hilda; Wuithiranyagool, Taweesak; Higgs, Stephen; Vanlandingham, Dana L.; Bala, Adil A.; Haas, Keith; Zerinque, Brian

    2004-01-01

    West Nile virus (WNV) was detected in 11 dead birds and two mosquito pools collected in east Texas and southern Louisiana during surveillance studies in the winter of 2003 to 2004. These findings suggest that WNV is active throughout the year in this region of the United States. PMID:15498169

  6. Strengthening malaria prevention and control: integrating West African militaries' malaria control efforts. The inaugural meeting of the West African Malaria Task Force, April 24-26, 2013, Accra, Ghana.

    PubMed

    McCollum, Jeffrey T; Hanna, Refaat; Halbach, Alaina C; Cummings, James F

    2015-01-01

    From April 24 to 26, 2013, the Armed Forces Health Surveillance Center and the U.S. Africa Command cosponsored the inaugural meeting of the West Africa Malaria Task Force in Accra, Ghana. The meeting's purpose was to identify common challenges, explore regional and transcontinental collaborations, and to share knowledge about best practices in the fight against malaria in West Africa. Military representatives from Benin, Burkina Faso, Ghana, Liberia, Niger, Nigeria, Senegal, and Togo participated in the Task Force; various U.S. Government agencies were also represented, including the Department of Defense, the Centers for Disease Control and Prevention, and the Agency for International Development. African nation participants presented brief overviews of their military's malaria prevention and control measures, surveillance programs, diagnostic capabilities, and treatment regimens emphasizing gaps within existing programs. Representatives from U.S. agencies discussed activities and capabilities relevant for the region, challenges and lessons learned regarding malaria, and highlighted opportunities for enhanced partnerships to counter malaria in West Africa. This article summarizes the major conclusions of the Task Force meeting, identifies relevant focus areas for future Task Force activities, and outlines opportunities for further inclusion of West African militaries to improve regional malaria surveillance and control efforts.

  7. Metamorphic waters from the pacific tectonic belt of the west coast of the United States

    USGS Publications Warehouse

    Barnes, I.

    1970-01-01

    Waters unusually rich in ammonia, boron, carbon dioxide, hydrogen sulfide, and hydrocarbons are found in more than 100 localities along the Pacific coast of the United States. The waters are believed to be products of low-grade metamorphism of marine sediments. The marine sedimentary rocks would have to be tectonically emplaced below crystalline rocks in many places. Mercury are deposits are probably also products of the low-grade metamorphism.

  8. Metamorphic waters from the pacific tectonic belt of the west coast of the United States.

    PubMed

    Barnes, I

    1970-05-22

    Waters unusually rich in ammonia, boron, carbon dioxide, hydrogen sulfide, and hydrocarbons are found in more than 100 localities along the Pacific coast of the United States. The waters are believed to be products of low-grade metamorphism of marine sediments. The marine sedimentary rocks would have to be tectonically emplaced below crystalline rocks in many places. Mercury ore deposits are probably also products of the low-grade metamorphism.

  9. Determinants of suboptimal complementary feeding practices among children aged 6-23 months in four anglophone West African countries.

    PubMed

    Issaka, Abukari I; Agho, Kingsley E; Page, Andrew N; Burns, Penelope L; Stevens, Garry J; Dibley, Michael J

    2015-10-01

    Suboptimal complementary feeding practices have a detrimental impact on a child's growth, health and development in the first two years of life. They lead to child malnutrition, which contributes to the high prevalence of stunting (38%) and underweight (28%) reported for children <5 years of age in Sub-Saharan Africa. This study analysed complementary feeding practices in four anglophone West African countries (Ghana, Liberia, Nigeria and Sierra Leone) using the most recent Demographic and Health Surveys. The study covered 12 623 children aged 6-23 months from four anglophone West African countries (Ghana: 822 children: Liberia: 1458 children, Nigeria: 8786 children and Sierra Leone: 1557 children). Four complementary feeding indicators were examined against a set of individual-, household- and community-level factors, using multiple regression analysis. Multivariate analyses found that lack of post-natal contacts with health workers, maternal illiteracy and geographical region were common determinants of delayed introduction of solid, semi-solid or soft foods across all four countries. Predictors for minimum dietary diversity, minimum meal frequency and minimum acceptable diet included children aged 6-11 months, administrative/geographical region, poorer household income and limited access to media. The authors recommend that the four anglophone West African countries studied should prioritise efforts to improve complementary feeding practices in order to reduce child morbidity and mortality. Interventional studies on complementary feeding should target those from poor and illiterate households.

  10. Interannual variability in phytoplankton pigment distribution during the spring transition along the west coast of North America

    NASA Technical Reports Server (NTRS)

    Thomas, A. C.; Strub, P. T.

    1989-01-01

    A 5-year time series of coastal zone color scanner imagery (1980-1983, 1986) is used to examine changes in the large-scale pattern of chlorophyll pigment concentration coincident with the spring transition in winds and currents along the west coast of North America. The data show strong interannual variability in the timing and spatial patterns of pigment concentration at the time of the transition event. Interannual variability in the response of pigment concentration to the spring transition appears to be a function of spatial and temporal variability in vertical nutrient flux induced by wind mixing and/or the upwelling initiated at the time of the transition. Interannual differences in the mixing regime are illustrated with a one-dimensional mixing model.

  11. Dominant role of winds near Sri Lanka in driving seasonal sea level variations along the west coast of India

    NASA Astrophysics Data System (ADS)

    Suresh, I.; Vialard, J.; Izumo, T.; Lengaigne, M.; Han, W.; McCreary, J.; Muraleedharan, P. M.

    2016-07-01

    The strong seasonal cycle of sea level along the west coast of India (WCI) has important consequences for ecosystem and fisheries, and the Lakshadweep high/low in the southeast Arabian Sea is important for fisheries and the Indian summer monsoon. Previous studies suggested that WCI sea level variability is primarily driven by remote wind forcing from the Bay of Bengal and equatorial Indian Ocean through coastal Kelvin wave propagation. Using a linear ocean model, we demonstrate that wind forcing in a relatively small region around the southern tip of India and east of Sri Lanka contribute to ~60% of this variability. Wind variations from the rest of the Bay and the equator only account respectively for ~20% and ~10%. Sea level signals forced by the "southern tip" winds extend westward into the eastern Arabian Sea through Rossby wave propagation, with more than 50% contribution in the Lakshadweep high/low region.

  12. Developing erosion models for integrated coastal zone management: a case study of The New Caledonia west coast.

    PubMed

    Dumas, Pascal; Printemps, Julia; Mangeas, Morgan; Luneau, Gaelle

    2010-01-01

    The tropical climate and human pressures (mining industry, forest fires) cause significant sediment inputs into the New Caledonia lagoon and are a major cause of degradation of the fringing reefs. The erosion process is spatially characterized on the west coast of New Caledonia to assess potential sediment inputs in the marine area. This paper describes the methodologies that are used to map soil sensitivity to erosion using remote sensing and a geographic information system tool. A cognitive approach, multi-criteria evaluation model and Universal Soil Loss Equation are implemented. This article compares the relevance of each model in order to spatialize and quantify potential erosion at catchment basin scale. These types of studies provide valuable results for focusing on areas subject to erosion and serve as a decision-making tool for the minimization of lagoon vulnerability to the natural and human dynamics on the level of the catchment basins.

  13. Microdistribution within a population of Acrocnida brachiata (Montagu), (Echinodermata: Ophiuroidea) in Little Killary, west coast of Ireland

    NASA Astrophysics Data System (ADS)

    Makra, A.; Keegan, B. F.

    1998-03-01

    Acrocnida brachiata (Montagu), like many other infaunal ophiuroids, has a penchant for gregariousness. In Little Killary, a small embayment on the west coast of Ireland, it colonises an extensive tract of sandy inshore ground (ca 7 m depth), at densities of 150-200 individuals/m2. In the course of a two-year study, variation in regular suction-sampling returns prompted a detailed study of the species distribution pattern. Towards this end, 256 contiguous and stratified core samples were taken along a line of transect, in May 1995. These showed randomness with respect to the population at large, but exposed an aggregated distribution for juveniles and adults separately, at different levels within the sediment. Juveniles formed wide, ‘loose’ patches in the surficial deposit, while adults formed smaller, denseer patches deeper within the sediment. It remains to be seen what this approach may expose, when applied in different seasons, or during different phases of the species life cycle.

  14. Ground-water quality of coastal aquifer systems in the West Coast Basin, Los Angeles County, California, 1999-2002

    USGS Publications Warehouse

    Land, Michael; Reichard, Eric G.; Crawford, Steven M.; Everett, Rhett; Newhouse, Mark W.; Williams, Colin F.

    2004-01-01

    The extensive use of ground water throughout the Central and West Coast Basins of Los Angeles County during the first half of the 20th century resulted in declining water levels, widespread seawater intrusion, and deterioration of water quality along most reaches of the coast. In order to control seawater intrusion in the West Coast Basin, freshwater is injected into a series of wells at two seawater barrier projects. In order to better understand the processes of seawater intrusion and the efficiency of current barrier operation, data were collected from multiple-well monitoring sites installed by the U.S. Geological Survey, from local observation wells, and from production wells. The occurrence and areal extent of native, saline, and recently injected ground water near the coast were defined through the collection and analysis of inorganic and isotopic water-quality data and geophysical logs. Most water in the West Coast Basin with a dissolved-solids concentration less than 500 milligrams per liter generally has a sodium-bicarbonate to sodium/calcium-bicarbonate character. Water with a dissolved-solids concentration greater than 1,000 milligrams per liter also contains variable amounts of calcium and sodium, but chloride is predominant. Most of these high-dissolved-solids wells are perforated in the Upper aquifer systems; several have dissolved-chloride values near that of seawater. Elevated chloride concentrations were measured at many wells in both the Upper and Lower aquifer systems inland from the barrier projects. Although water levels have increased in many wells over the last 30 years, some of the wells do not show a corresponding decrease in dissolved chloride. A detailed assessment of saline ground water was provided by examining the ratios of chloride to bromide, iodide, and boron. Seawater-freshwater mixing lines were constructed using all three ratios. These ion ratios also identify water affected by mixing with injected imported water and oil

  15. Exploring child prostitution in a major city in the West African region.

    PubMed

    Hounmenou, Charles

    2016-09-01

    The study explored the characteristics of child prostitution in a major city in the West African region. A convenience sample of children in prostitution, specifically girls below age 18 (n=243), were recruited on 83 prostitution sites identified in Ouagadougou, the capital city of Burkina Faso. A survey instrument, consisting of 71 closed-ended question items, was used to explore various variables including profile of children in prostitution, factors of vulnerability to prostitution; prostitution practices, compensations and related issues in child prostitution. The findings show that most children in prostitution in the city were from Burkina Faso (63%) and Nigeria (30%), two countries that do not share borders. Most native respondents practiced prostitution for survival and to support their families. In contrast, all the respondents from Nigeria practiced prostitution as victims of international sex trafficking. An important finding was that 77% of the children in prostitution surveyed were educated. Among the respondents, there were similarities in the major life events that contributed to their situation of prostitution. These life events include early separation with parents, sexual abuse, foster care, and forced marriage. Implications for policy, practice and research are discussed. PMID:27490517

  16. Changing causes of death in the West African town of Banjul, 1942-97.

    PubMed Central

    van der Sande, M. A.; Inskip, H. M.; Jaiteh, K. O.; Maine, N. P.; Walraven, G. E.; Hall, A. J.; McAdam, K. P.

    2001-01-01

    OBJECTIVE: To determine trends in the causes of death in a West African town. Mortality caused by infectious diseases is reported to be declining while degenerative and man-made mortality factors are increasingly significant. Most mortality analyses for sub-Saharan Africa have involved extrapolation and have not been derived from community-based data. METHODS: Historical data on causes of death coded by physicians were analysed for the urban population of Banjul for the period 1942-97. As the calculation of rates is not possible in the absence of a reliable population denominator, age-standardized proportional mortality ratios (PMRs) for men and women by major groups of causes of death were calculated, using the 1942-49 data for reference purposes. FINDINGS: Most deaths were attributable to communicable diseases. There was a shift in proportional mortality over the study period: the contribution of communicable diseases declined and that of noncommunicable diseases and injuries increased. These trends were more marked among men than women. CONCLUSION: The data illustrate that while noncommunicable diseases and injuries are emerging as important contributors to mortality in sub-Saharan Africa, communicable diseases remain significant causes of mortality and should not be neglected. PMID:11242820

  17. Comparative multivariate analysis of biometric traits of West African Dwarf and Red Sokoto goats.

    PubMed

    Yakubu, Abdulmojeed; Salako, Adebowale E; Imumorin, Ikhide G

    2011-03-01

    The population structure of 302 randomly selected West African Dwarf (WAD) and Red Sokoto (RS) goats was examined using multivariate morphometric analyses. This was to make the case for conservation, rational management and genetic improvement of these two most important Nigerian goat breeds. Fifteen morphometric measurements were made on each individual animal. RS goats were superior (P<0.05) to the WAD for the body size and skeletal proportions investigated. The phenotypic variability between the two breeds was revealed by their mutual responses in the principal components. While four principal components were extracted for WAD goats, three components were obtained for their RS counterparts with variation in the loading traits of each component for each breed. The Mahalanobis distance of 72.28 indicated a high degree of spatial racial separation in morphology between the genotypes. The Ward's option of the cluster analysis consolidated the morphometric distinctness of the two breeds. Application of selective breeding to genetic improvement would benefit from the detected phenotypic differentiation. Other implications for management and conservation of the goats are highlighted. PMID:21080228

  18. Exploring child prostitution in a major city in the West African region.

    PubMed

    Hounmenou, Charles

    2016-09-01

    The study explored the characteristics of child prostitution in a major city in the West African region. A convenience sample of children in prostitution, specifically girls below age 18 (n=243), were recruited on 83 prostitution sites identified in Ouagadougou, the capital city of Burkina Faso. A survey instrument, consisting of 71 closed-ended question items, was used to explore various variables including profile of children in prostitution, factors of vulnerability to prostitution; prostitution practices, compensations and related issues in child prostitution. The findings show that most children in prostitution in the city were from Burkina Faso (63%) and Nigeria (30%), two countries that do not share borders. Most native respondents practiced prostitution for survival and to support their families. In contrast, all the respondents from Nigeria practiced prostitution as victims of international sex trafficking. An important finding was that 77% of the children in prostitution surveyed were educated. Among the respondents, there were similarities in the major life events that contributed to their situation of prostitution. These life events include early separation with parents, sexual abuse, foster care, and forced marriage. Implications for policy, practice and research are discussed.

  19. Physical impacts of regional climate change in the West African Sahel and the question of desertification

    SciTech Connect

    Nicholson, S.E.; Ba, M.

    1997-11-01

    The question of desertification is examined in the West African Sahel region by considering various physical indicators assumed to accompany this process. The study considers only the past 14 years, since the availability of comprehensive satellite data sets. The physical indicators examined include vegetation cover, surface albedo, soil moisture, wind-borne dust, river flow, lakes, and the ratio of available moisture to vegetation growth. Vegetation cover and albedo are assessed from satellite data. Soil moisture is assessed using a surface hydrologic model. Dust is estimated from visibility measurements. The most important results are that: (1) there is no progressive change in the vegetation cover, (2) an increase of albedo as the region dries up cannot be documented, and (3) there has been a tremendous increase in wind-borne dust over the Sahel. The vegetation cover responds almost directly to rainfall and the movement of the desert boundary corresponds roughly to rainfall fluctuations. The most important meteorological effect of the drought and/or desertification in the Sahel may be the enhanced dust generation, with the region becoming a major global source of atmospheric mineral dust. 5 refs., 7 figs., 1 tab.

  20. In Vitro Activity of Selected West African Medicinal Plants against Mycobacterium ulcerans Disease.

    PubMed

    Tsouh Fokou, Patrick Valere; Kissi-Twum, Abena Adomah; Yeboah-Manu, Dorothy; Appiah-Opong, Regina; Addo, Phyllis; Tchokouaha Yamthe, Lauve Rachel; Ngoutane Mfopa, Alvine; Fekam Boyom, Fabrice; Nyarko, Alexander Kwadwo

    2016-01-01

    Buruli ulcer (BU) is the third most prevalent mycobacteriosis, after tuberculosis and leprosy. The currently recommended combination of rifampicin-streptomycin suffers from side effects and poor compliance, which leads to reliance on local herbal remedies. The objective of this study was to investigate the antimycobacterial properties and toxicity of selected medicinal plants. Sixty-five extracts from 27 plant species were screened against Mycobacterium ulcerans and Mycobacterium smegmatis, using the Resazurin Microtiter Assay (REMA). The cytotoxicity of promising extracts was assayed on normal Chang liver cells by an MTT assay. Twenty five extracts showed activity with minimal inhibitory concentration (MIC) values ranging from 16 µg/mL to 250 µg/mL against M. smegmatis, while 17 showed activity against M. ulcerans with MIC values ranging from 125 µg/mL to 250 µg/mL. In most of the cases, plant extracts with antimycobacterial activity showed no cytotoxicity on normal human liver cells. Exception were Carica papaya, Cleistopholis patens, and Polyalthia suaveolens with 50% cell cytotoxic concentrations (CC50) ranging from 3.8 to 223 µg/mL. These preliminary results support the use of some West African plants in the treatment of Buruli ulcer. Meanwhile, further studies are required to isolate and characterize the active ingredients in the extracts. PMID:27089314

  1. Long-term Variability of NorthWest African coastal upwelling

    NASA Astrophysics Data System (ADS)

    Wade, Malick; Rodríguez-Fonseca, Belen; Lazar, Alban

    2014-05-01

    The NorthWest African sea surface temperature variability can be due to changes in the coastal upwelling system, which in turn can be due to alterations in local winds, global winds induced by teleconnections and propagation of waves from wind burst in remote regions. The two last processes could be due in turn to changes in the sea surface temperature in extended regions remote from the upwelling region, as changes in Pacific SSTs associated with ENSO, or in the Equatorial Atlantic SSTs. This work demonstrates that the whole signal cannot be explained by local wind/Ekman pumping and large scale winds induced by teleconnections play an important role. Using observational data of SSTs and winds from atmospheric reanalysis, and applying different statistical technics, as correlation analysis, filtering and discriminant analysis, the different influences and its stationarity along the observational period are tested pointing to the non stationarity of El Niño influence in FMA and to other possible predictors influencing in the region.

  2. Non-Contaminating Camouflage: Multifunctional Skin Microornamentation in the West African Gaboon Viper (Bitis rhinoceros)

    PubMed Central

    Spinner, Marlene; Gorb, Stanislav N.; Balmert, Alexander; Bleckmann, Horst; Westhoff, Guido

    2014-01-01

    The West African Gaboon viper (Bitis rhinoceros) has an extraordinary coloration of pale brown and velvety black markings. The velvety black appearance is caused by a unique hierarchical surface structures which was not found on the pale brown scales. In the present study we examined the wettability of the vipeŕs scales by measuring contact angles of water droplets. Velvet black scale surfaces had high static contact angles beyond 160° and low roll-off angles below 20° indicating an outstanding superhydrophobicity. Our calculations showed that the Cassie-Baxter model describes well wettability effects for these surfaces. Self-cleaning capabilities were determined by contaminating the scales with particles and fogging them until droplets formed. Black scales were clean after fogging, while pale scales stayed contaminated. Black scales feature multifunctional structures providing not only water-repellent but also self-cleaning properties. The pattern of nanoridges can be used as a model for surface-active technical surfaces. PMID:24599379

  3. Deep-sea environment and biodiversity of the West African Equatorial margin

    NASA Astrophysics Data System (ADS)

    Sibuet, Myriam; Vangriesheim, Annick

    2009-12-01

    The long-term BIOZAIRE multidisciplinary deep-sea environmental program on the West Equatorial African margin organized in partnership between Ifremer and TOTAL aimed at characterizing the benthic community structure in relation with physical and chemical processes in a region of oil and gas interest. The morphology of the deep Congo submarine channel and the sedimentological structures of the deep-sea fan were established during the geological ZAIANGO project and helped to select study sites ranging from 350 to 4800 m water depth inside or near the channel and away from its influence. Ifremer conducted eight deep-sea cruises on board research vessels between 2000 and 2005. Standardized methods of sampling together with new technologies such as the ROV Victor 6000 and its associated instrumentation were used to investigate this poorly known continental margin. In addition to the study of sedimentary environments more or less influenced by turbidity events, the discovery of one of the largest cold seeps near the Congo channel and deep coral reefs extends our knowledge of the different habitats of this margin. This paper presents the background, objectives and major results of the BIOZAIRE Program. It highlights the work achieved in the 16 papers in this special issue. This synthesis paper describes the knowledge acquired at a regional and local scale of the Equatorial East Atlantic margin, and tackles new interdisciplinary questions to be answered in the various domains of physics, chemistry, taxonomy and ecology to better understand the deep-sea environment in the Gulf of Guinea.

  4. Spatial and Temporal Occurrence of Blue Whales off the U.S. West Coast, with Implications for Management

    PubMed Central

    Irvine, Ladd M.; Mate, Bruce R.; Winsor, Martha H.; Palacios, Daniel M.; Bograd, Steven J.; Costa, Daniel P.; Bailey, Helen

    2014-01-01

    Mortality and injuries caused by ship strikes in U.S. waters are a cause of concern for the endangered population of blue whales (Balaenoptera musculus) occupying the eastern North Pacific. We sought to determine which areas along the U.S. West Coast are most important to blue whales and whether those areas change inter-annually. Argos-monitored satellite tags were attached to 171 blue whales off California during summer/early fall from 1993 to 2008. We analyzed portions of the tracks that occurred within U.S. Exclusive Economic Zone waters and defined the ‘home range’ (HR) and ‘core areas’ (CAU) as the 90% and 50% fixed kernel density distributions, respectively, for each whale. We used the number of overlapping individual HRs and CAUs to identify areas of highest use. Individual HR and CAU sizes varied dramatically, but without significant inter-annual variation despite covering years with El Niño and La Niña conditions. Observed within-year differences in HR size may represent different foraging strategies for individuals. The main areas of HR and CAU overlap among whales were near highly productive, strong upwelling centers that were crossed by commercial shipping lanes. Tagged whales generally departed U.S. Exclusive Economic Zone waters from mid-October to mid-November, with high variability among individuals. One 504-d track allowed HR and CAU comparisons for the same individual across two years, showing similar seasonal timing, and strong site fidelity. Our analysis showed how satellite-tagged blue whales seasonally used waters off the U.S. West Coast, including high-risk areas. We suggest possible modifications to existing shipping lanes to reduce the likelihood of collisions with vessels. PMID:25054829

  5. Spatial and temporal occurrence of blue whales off the U.S. West Coast, with implications for management.

    PubMed

    Irvine, Ladd M; Mate, Bruce R; Winsor, Martha H; Palacios, Daniel M; Bograd, Steven J; Costa, Daniel P; Bailey, Helen

    2014-01-01

    Mortality and injuries caused by ship strikes in U.S. waters are a cause of concern for the endangered population of blue whales (Balaenoptera musculus) occupying the eastern North Pacific. We sought to determine which areas along the U.S. West Coast are most important to blue whales and whether those areas change inter-annually. Argos-monitored satellite tags were attached to 171 blue whales off California during summer/early fall from 1993 to 2008. We analyzed portions of the tracks that occurred within U.S. Exclusive Economic Zone waters and defined the 'home range' (HR) and 'core areas' (CAU) as the 90% and 50% fixed kernel density distributions, respectively, for each whale. We used the number of overlapping individual HRs and CAUs to identify areas of highest use. Individual HR and CAU sizes varied dramatically, but without significant inter-annual variation despite covering years with El Niño and La Niña conditions. Observed within-year differences in HR size may represent different foraging strategies for individuals. The main areas of HR and CAU overlap among whales were near highly productive, strong upwelling centers that were crossed by commercial shipping lanes. Tagged whales generally departed U.S. Exclusive Economic Zone waters from mid-October to mid-November, with high variability among individuals. One 504-d track allowed HR and CAU comparisons for the same individual across two years, showing similar seasonal timing, and strong site fidelity. Our analysis showed how satellite-tagged blue whales seasonally used waters off the U.S. West Coast, including high-risk areas. We suggest possible modifications to existing shipping lanes to reduce the likelihood of collisions with vessels.

  6. Brominated flame retardants and halogenated phenolic compounds in North American west coast bald eaglet (Haliaeetus leucocephalus) plasma.

    PubMed

    McKinney, Melissa A; Cesh, Lillian S; Elliott, John E; Williams, Tony D; Garcelon, David K; Letcher, Robert J

    2006-10-15

    We report on the identity, characterization, and spatial trends of several brominated flame retardants and hydroxylated (OH-) and methoxylated (MeO-) organohalogen contaminants in bald eagle (Haliaeetus leucocephalus) nestling plasma collected from sites along the west coast of North America. Samples were from four southwestern British Columbia (BC) locations, a reference site in northern BC (Fort St. James; FSJ), and from Santa Catalina Island, CA (SCI), an area of high DDT and PCB contamination. Mean concentrations of sigma polybrominated diphenyl ether (sigma PBDE (8 congeners monitored); 1.78-8.49 ng/g), sigma OH-polychlorinated biphenyl (sigma OH-PCB (30 congeners monitored); 0.44-0.87 ng/g), and sigma OH-PBDE (14 congeners monitored; 0.31-0.92 ng/g) were similar in eaglets from southwestern BC yet lower than for SCl and significantly higher than for FSJ. Dominant PBDE congeners were BDE47, BDE99, and BDE100, but SCl eaglets also contained low levels of higher brominated congeners. 4-OH-CB187 and 4'-OH-CB202 accounted for 65-100% of sigma OH-PCB in all BC eaglets, with 4'-OH-CB202 as well as 3'-OH-CB138 and 4-OH-CB146 dominating in SCl eaglets. Ostensibly of biogenic origin, 6'-OH-BDE49 and 6-OH-BDE47 were found in BC nestlings. Only 4'-OH-BDE49 (2.10 ng/g) was found in SCl eaglets. MeO-PBDEs and total hexabromocyclododecane (HBCD) were not found in any birds, but the polybrominated biphenyl BB101 was detected in southwestern BC samples. This study demonstrates that west coast North American bald eagles contain previously unreported organohalogens, which have the potential to impact the health and survival of these raptors.

  7. Spatial and temporal occurrence of blue whales off the U.S. West Coast, with implications for management.

    PubMed

    Irvine, Ladd M; Mate, Bruce R; Winsor, Martha H; Palacios, Daniel M; Bograd, Steven J; Costa, Daniel P; Bailey, Helen

    2014-01-01

    Mortality and injuries caused by ship strikes in U.S. waters are a cause of concern for the endangered population of blue whales (Balaenoptera musculus) occupying the eastern North Pacific. We sought to determine which areas along the U.S. West Coast are most important to blue whales and whether those areas change inter-annually. Argos-monitored satellite tags were attached to 171 blue whales off California during summer/early fall from 1993 to 2008. We analyzed portions of the tracks that occurred within U.S. Exclusive Economic Zone waters and defined the 'home range' (HR) and 'core areas' (CAU) as the 90% and 50% fixed kernel density distributions, respectively, for each whale. We used the number of overlapping individual HRs and CAUs to identify areas of highest use. Individual HR and CAU sizes varied dramatically, but without significant inter-annual variation despite covering years with El Niño and La Niña conditions. Observed within-year differences in HR size may represent different foraging strategies for individuals. The main areas of HR and CAU overlap among whales were near highly productive, strong upwelling centers that were crossed by commercial shipping lanes. Tagged whales generally departed U.S. Exclusive Economic Zone waters from mid-October to mid-November, with high variability among individuals. One 504-d track allowed HR and CAU comparisons for the same individual across two years, showing similar seasonal timing, and strong site fidelity. Our analysis showed how satellite-tagged blue whales seasonally used waters off the U.S. West Coast, including high-risk areas. We suggest possible modifications to existing shipping lanes to reduce the likelihood of collisions with vessels. PMID:25054829

  8. The impact of the 2009-10 El Niño Modoki on U.S. West Coast beaches

    USGS Publications Warehouse

    Barnard, Patrick L.; Allan, Jonathan; Hansen, Jeff E.; Kaminsky, George M.; Ruggiero, Peter; Doria, André

    2011-01-01

    High-resolution beach morphology data collected along much of the U.S. West Coast are synthesized to evaluate the coastal impacts of the 2009-10 El Nio. Coastal change observations were collected as part of five beach monitoring programs that span between 5 and 13 years in duration. In California, regional wave and water level data show that the environmental forcing during the 2009-10 winter was similar to the last significant El Nio of 1997-98, producing the largest seasonal shoreline retreat and/or most landward shoreline position since monitoring began. In contrast, the 2009-10 El Nio did not produce anomalously high mean winter-wave energy in the Pacific Northwest (Oregon and Washington), although the highest 5% of the winter wave-energy measurements were comparable to 1997-98 and two significant non-El Nio winters. The increase in extreme waves in the 2009-10 winter was coupled with elevated water levels and a more southerly wave approach than the long-term mean, resulting in greater shoreline retreat than during 1997-98, including anomalously high shoreline retreat immediately north of jetties, tidal inlets, and rocky headlands. The morphodynamic response observed throughout the U.S. West Coast during the 2009-10 El Nio is principally linked to the El Nio Modoki phenomena, where the warm sea surface temperature (SST) anomaly is focused in the central equatorial Pacific (as opposed to the eastern Pacific during a classic El Nio), featuring a more temporally persistent SST anomaly that results in longer periods of elevated wave energy but lower coastal water levels. ?? 2011 by the American Geophysical Union.

  9. The impact of the 2009-10 El Niño Modoki on U.S. West Coast beaches

    USGS Publications Warehouse

    Barnard, Patrick L.; Allan, Jonathan; Hansen, Jeff E.; Kaminsky, George M.; Ruggiero, Peter; Doria, André

    2011-01-01

    High-resolution beach morphology data collected along much of the U.S. West Coast are synthesized to evaluate the coastal impacts of the 2009–10 El Niño. Coastal change observations were collected as part of five beach monitoring programs that span between 5 and 13 years in duration. In California, regional wave and water level data show that the environmental forcing during the 2009–10 winter was similar to the last significant El Niño of 1997–98, producing the largest seasonal shoreline retreat and/or most landward shoreline position since monitoring began. In contrast, the 2009–10 El Niño did not produce anomalously high mean winter-wave energy in the Pacific Northwest (Oregon and Washington), although the highest 5% of the winter wave-energy measurements were comparable to 1997–98 and two significant non-El Niño winters. The increase in extreme waves in the 2009–10 winter was coupled with elevated water levels and a more southerly wave approach than the long-term mean, resulting in greater shoreline retreat than during 1997–98, including anomalously high shoreline retreat immediately north of jetties, tidal inlets, and rocky headlands. The morphodynamic response observed throughout the U.S. West Coast during the 2009–10 El Niño is principally linked to the El Niño Modoki phenomena, where the warm sea surface temperature (SST) anomaly is focused in the central equatorial Pacific (as opposed to the eastern Pacific during a classic El Niño), featuring a more temporally persistent SST anomaly that results in longer periods of elevated wave energy but lower coastal water levels.

  10. Distribution of Sargassum muticum on the North West coast of Spain: Relationships with urbanization and community diversity

    NASA Astrophysics Data System (ADS)

    Incera, Mónica; Olabarria, Celia; Cacabelos, Eva; César, Javier; Troncoso, Jesús S.

    2011-04-01

    Invasions are common in coastal marine environments where proximity to urban areas should influence the number of non-native organisms due to the likelihood of unintentional introductions from urban centers. Invasive species are widely recognised as important agents of global change, and can colonize new habitats and even cause local extinction of native species. This study was focused on the invasive marine macroalga Sargassum muticum, a problematic invasive species on the West coast of America and in European waters. An intensive survey was carried out along the Galician coast (North West of Spain) from March to August 2008 to determine the current distribution of this species, and its relationship with level of urbanization and native macroalgal diversity. We sampled the presence of S. muticum and native macroalgae in the mid and low intertidal zones of twenty rocky shores distributed along ten rias. Rias were grouped into high and scarcely urbanized based on their population density. Results indicated that S. muticum was present in nine out of the ten rias, confirming its presence in most of the intertidal rocky shores of Galicia twenty years after it was first observed. The presence of S. muticum was not related to the degree of urbanization of the rias, and its distribution and abundance did not seem to be influenced by diversity or functional groups of native algae. In addition, there was a great variability in the percentage cover, number and length of individuals amongst localities and rias suggesting that both large-scale and local processes may play a role in the distribution of this species. This study highlights the importance of future research into the distribution and impact of introduced algae and proves the urgent need for monitoring programmes and increasing efforts to prevent and control new introductions.

  11. The Lake Bosumtwi Drilling Project: A 1 Ma West African Paleoclimate Record

    NASA Astrophysics Data System (ADS)

    Peck, J. A.; Heil, C.; King, J. W.; Scholz, C. A.; Shanahan, T. M.; Overpeck, J. T.; Fox, P. A.; Amoako, P. Y.; Forman, S. L.; Koeberl, C.; Milkereit, B.

    2005-12-01

    Lake Bosumtwi occupies a 1.07 Ma impact crater located in Ghana, West Africa centered at 06*32'N and 01*25'W. This 78 m deep, hydrologically-closed lake has a water budget extremely sensitive to the precipitation/evapotranspiration balance and is located in the path of the seasonal migration of the ITCZ. Therefore, Lake Bosumtwi is ideally situated to provide a long record of change in North African monsoon strength. In addition, the stratified water column allows for the preservation of finely-laminated sediments and the potential for high-resolution (annual) paleoclimate reconstruction. Using the GLAD800 lake drilling system, five drill sites were occupied along a water-depth transect in order to facilitate the reconstruction of the lake level history. At these five sites, a total of 14 separate holes were drilled yielding a total sediment recovery of 1,833 m. The shallow water drill sites consist of alternating laminated lacustrine mud (deepwater environment), moderately-sorted sand (nearshore beach environment) and sandy gravel (fluvial or lake marginal environments). These sediment cores and seismic reflection profiles are being used to construct a basin-wide stratigraphic framework, in order to extend further back in time the present Bosumtwi lake level histories obtained from highstand terraces and short piston cores. At a deep water site, the complete 1 Ma lacustrine stratigraphic section was recovered in 294 m deep holes that ended in impact-glass bearing, accretionary lapilli fallout representing the initial days of sedimentation. The lowermost lacustrine sediment is a bioturbated, light-gray mud with abundant gastropod shells indicating that a shallow-water oxic lake environment was established in the crater. Much of the overlying 294 m of mud is laminated thus these sediment cores will provide a unique 1 million year record of tropical African climate change. Two contrasting litholgies identified in the dated, upper part of the deep water drill hole

  12. Distribution of Benthesicymustanneri Faxon, 1893 (Dendrobranchiata, Benthesicymidae) off the west coast of Mexico and notes on its morphology.

    PubMed

    Hendrickx, Michel E; Papiol, Vanesa

    2015-01-01

    A large series of specimens of Benthesicymustanneri Faxon, 1893 (Dendrobranchiata; Benthesicymidae) was collected during an extensive survey of deep-water invertebrate fauna off western Mexico. In total, 61 males and 122 females (M:F ratio = 1:2) from 44 sampling stations were examined, considerably increasing the number of known specimens and sampling localities for this species which is widely distributed along the Pacific coast of Mexico. The collection is the largest available for this species to date and presents first records from off the west coast of the Baja California Peninsula and a slight increase of the northernmost record within the Gulf of California. On the whole, females grew larger than males. The petasma of males of different sizes and the female thelycum of Benthesicymustanneri are illustrated. The petasma of Benthesicymustanneri presents a ventrolateral crescent-shape process otherwide found only in Benthesicymustirmiziae Crosnier, 1978 and in Benthesicymusbartletti S.I. Smith, 1882. A key to the four species of Benthesicymus presently known from the eastern Pacific is presented. PMID:25632254

  13. Association and distribution of the ciliate Orchitophrya stellarum with asteriid sea stars on the west coast of North America.

    PubMed

    Stickle, William B; Kozloff, Eugene N

    2008-06-19

    The association of the scuticociliate Orchitophrya stellarum with 3 species of asteriid sea stars from the west coast of North America was studied by flushing the gonopore region with seawater and spawning the sea stars, along a latitudinal gradient of 2549 km between Pigeon Point, California, and Kodiak, Alaska. Asterias forbesii and A. rubens from the Isles of Shoals, New Hampshire (east coast), were also sampled. The ciliate was found on the aboral surface of both sexes of reproductively ripe Evasterias troschelii, Leptasterias spp., and Pisaster ochraceus with a maximum intensity of association occurring at Cape Arago, Oregon, and Clallum Bay and Manchester Dock, Washington. A survey of gonad smears and hematoxylin and eosin-stained sections indicated that the ciliate was only present in males. Spring-spawning E. troschelii and P. ochraceus are more negatively impacted by the ciliate than are winter-spawning Leptasterias spp. as judged by a skewed sex ratio and sex size differences, which may be associated with seasonal differences in water temperature affecting the growth rate of O. stellarum. The external morphology of O. stellarum appears to be similar throughout the geographical range surveyed.

  14. Phylogeography and reproductive variation of the poecilogonous polychaete Boccardia proboscidea (Annelida: Spionidae) along the West Coast of North America.

    PubMed

    Oyarzun, Fernanda X; Mahon, Andrew R; Swalla, Billie J; Halanych, Kenneth M

    2011-01-01

    The ability to produce more than one kind of offspring, or poecilogony, is a striking example of reproductive variability. Traditionally, larval nutrition has been classified as a dichotomy: if offspring obtain nutrition from their mothers (lecithotrophy), there is lower fecundity and greater chance of offspring survival than when they get their nutrition from plankton (planktotrophy). The polychaete Boccardia proboscidea (Spionidae) produces both types of embryos using three different reproductive strategies. In this study, we examined the roles of genetic history and phenotypic plasticity on explaining natural variation in B. proboscidea along the Pacific coast of the United States using two genetic mitochondrial markers, 16S rDNA and Cyt b, and common garden experiments. These data show a single North American West Coast network that is structured, geographically, by the well-documented biogeographic break near Point Conception, California. The southern group within this network covers a smaller range, but has larger haplotype diversity, than the northern group. Some individuals differing in reproductive type had the same haplotype, indicating independence of these features; however, differences between laboratory and field data suggest additional geographic variation within one of the reproductive types. Females from higher latitudes provide offspring with larger supplies of extra embryonic nutrition than females from southern latitudes. Results herein suggest that both genetic history and developmental plasticity are playing a role in the maintenance of this reproductive polymorphism.

  15. Distribution of Benthesicymus tanneri Faxon, 1893 (Dendrobranchiata, Benthesicymidae) off the west coast of Mexico and notes on its morphology

    PubMed Central

    Hendrickx, Michel E.; Papiol, Vanesa

    2015-01-01

    Abstract A large series of specimens of Benthesicymus tanneri Faxon, 1893 (Dendrobranchiata; Benthesicymidae) was collected during an extensive survey of deep-water invertebrate fauna off western Mexico. In total, 61 males and 122 females (M:F ratio = 1:2) from 44 sampling stations were examined, considerably increasing the number of known specimens and sampling localities for this species which is widely distributed along the Pacific coast of Mexico. The collection is the largest available for this species to date and presents first records from off the west coast of the Baja California Peninsula and a slight increase of the northernmost record within the Gulf of California. On the whole, females grew larger than males. The petasma of males of different sizes and the female thelycum of Benthesicymus tanneri are illustrated. The petasma of Benthesicymus tanneri presents a ventrolateral crescent-shape process otherwide found only in Benthesicymus tirmiziae Crosnier, 1978 and in Benthesicymus bartletti S.I. Smith, 1882. A key to the four species of Benthesicymus presently known from the eastern Pacific is presented. PMID:25632254

  16. Haemonchotolerance in West African Dwarf goats: contribution to sustainable, anthelmintics-free helminth control in traditionally managed Nigerian dwarf goats.

    PubMed

    Chiejina, Samuel N; Behnke, Jerzy M; Fakae, Barineme B

    2015-01-01

    West African Dwarf (WAD) goats are extremely important in the rural village economy of West Africa, but still little is known about their biology, ecology and capacity to cope with gastrointestinal nematode (GIN) infections. Here, we summarise the history of this breed and explain its economic importance in rural West Africa. We review recent work showing that Nigerian WAD goats are highly trypanotolerant and resist infections with Haemonchus contortus more effectively than other breeds of domestic goat (haemonchotolerance). We believe that haemonchotolerance is largely responsible for the generally low level GIN infections and absence of clinical haemonchosis in WADs under field conditions, and has contributed to the relatively successful and sustainable, anthelmintics-free, small-scale system of goat husbandry in Nigeria's humid zone, and is immunologically based and genetically controlled. If haemonchotolerance can be shown to be genetically controlled, it should be possible to exploit the underlying genes to improve GIN resistance among productive fibre and milk producing breeds of goats, most of which are highly susceptible to nematode infections. Genetic resistance to GIN and trypanosome infections would obviate the need for expensive chemotherapy, mostly unaffordable to small-holder farmers in Africa, and a significant cost of goat husbandry in more developed countries. Either introgression of resistance alleles into susceptible breeds by conventional breeding, or transgenesis could be used to develop novel parasite-resistant, but highly productive breeds, or to improve the resistance of existing breeds, benefitting the local West African rural economy as well as global caprine livestock agriculture.

  17. Foraging ecology of an endemic shorebird, the African Black Oystercatcher ( Haematopus moquini) on the south-east coast of South Africa

    NASA Astrophysics Data System (ADS)

    Kohler, Sophie; Bonnevie, Bo; McQuaid, Christopher; Jaquemet, Sébastien

    2009-09-01

    We investigated small-medium (1-300 km) scale variation in the foraging ecology of the African Black Oystercatcher during its breeding season, using traditional diet analysis coupled with carbon and nitrogen stable isotope analysis. Fieldwork was conducted between January and March 2006 and 2007, on rocky shores on the south-east coast of South Africa at East London, Kenton and Port Elizabeth. Middens of shelled prey left by adults feeding their chicks were collected from five territories and the abundances of the collected prey on the foraging areas were estimated using quadrats. Blood samples from 45 birds (16 females, 10 males and 19 chicks) and tissues from the predominant prey species on the territory of each breeding pair were collected for isotope analysis. The Manly-Chesson selectivity index revealed that adults feed their chicks preferentially with the limpet Scutellastra cochlear and the Mediterranean mussel Mytilus galloprovincialis, if available. A slight enrichment in the 15N stable-carbon isotope signature was observed towards the west in both prey and oystercatchers. Differences in isotope signatures between males and females from the same breeding pair indicate sex-related differences in the diet. Both had signatures indicating a mixed diet, but with males exhibiting a signature closer to that of limpets and females closer to that of mussels. In the single case where mussels were rare on the feeding territory, the two members of a pair showed carbon signatures which were identical and very similar to that of limpets. These results indicate dietary partitioning between genders in breeding pairs.

  18. Nutrient environment of red tide- infested waters off south-west coast of India.

    PubMed

    Joseph, Thresiamma; Shaiju, P; Laluraj, C M; Balachandran, K K; Nair, M; George, Rejomon; Nair, K K C; Sahayak, Satish; Prabhakaran, M P

    2008-08-01

    The bloom-infested waters along the southwest coast of India were assessed to bring about the probable cause related to the excessive algal production. Low nitrate and silicate concentrations were concomitant with slightly higher levels of phosphate. The silicate depletion in the bloom area is possibly an indication of community succession (diatom to dinoflagellate), since it was completely utilized by the preceding diatom blooms. The dinoflagellates in this region could have been advected from the northern regions where it was noticed during the previous months. PMID:17879133

  19. PROCEEDINGS OF THE WEST COAST REGIONAL CONFERENCE ON RESEARCH RELATED TO BLIND AND SEVERELY VISUALLY IMPAIRED CHILDREN (SAN FRANCISCO, MARCH 8-10, 1965).

    ERIC Educational Resources Information Center

    CLARK, LESLIE L.; AND OTHERS

    THESE PROCEEDINGS WERE PREPARED FROM THE WEST COAST REGIONAL CONFERENCE ON RESEARCH RELATED TO BLIND AND SEVERELY VISUALLY IMPAIRED CHILDREN HELD MARCH 8-10, 1965. SURVEY RESULTS WERE PRESENTED WHICH INDICATED THE NUMBER OF BLIND, SEVERELY VISUALLY IMPAIRED, AND MULTIPLY HANDICAPPED CHILDREN IN CALIFORNIA AND THE INCIDENCE OF BLINDNESS IN CHILDREN…

  20. 77 FR 17086 - U.S. Customs and Border Protection 2012 West Coast Trade Symposium: “Transforming Trade for a...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-23

    ... Federal Register (77 FR 16048) on March 19, 2012, about the West Coast trade symposium which will be held... Symposium: ``Transforming Trade for a Stronger Economy'' AGENCY: U.S. Customs and Border Protection... ``Transforming Trade for a Stronger Economy''; and to inform the public that the fees have changed for...

  1. Persistent marine debris in the North Sea, Northwest Atlantic Ocean, Wider Caribbean Area, and the West Coast of Baja California. Final report

    SciTech Connect

    Heneman, B.

    1988-07-01

    Information on persistent marine debris (including plastics, glass, metal, and tar) in four study areas (North Sea, northwest Atlantic Ocean, Wider Caribbean Area, and the west coast of Baja California) was obtained through literature searches, a mailed survey, correspondence, interviews, and personal observations. All of the study areas except Baja California were found to have severe marine debris problems.

  2. Remote sensing survey applied to synthetic geological mapping in Ivory Coast (West Africa)

    NASA Astrophysics Data System (ADS)

    Deroin, Jean-Paul; Delor, Claude; Simeon, Yves; Yao, Bertin

    1994-12-01

    We have used remote sensing as an additional method in 1:200 000-scale reconnaissance mapping of the Ivory Coast. Landsat imagery was chosen for its low cost, and its interest for relatively small-scale work and its synthetic and multispectral properties. This proved perfectly satisfactory, especially in the bush savanna to the north of latitude 7 deg 30'. The imagery was also compared with aeromagnetic survey results. The lithostructural features revealed by MSS can be directly correlated with field observations. 1) Certain clear facies variations (amphibolites or gabbros among acidic rocks, for example) are spectrally well expressed. Conglomerates are commonly distinctive (on the Katiola sheet for example), when they are sufficiently extensive and they form ridges that can be followed several tens of kilometres. 2) The traces of planar structures can, at least locally, be followed and correlated with a regional schistosity. Certain features mappable on images confirm offset across transcurrent structures identified on the ground (N-S transcurrent fault zones, for example). Our experience in Ivory Coast shows that the use of Landsat MSS imagery should systematically be considered for any small- scale studies in which only a small part of the budget can be attributed to remote sensing.

  3. Blindness and Visual Impairment in an Urban West African Population: The Tema Eye Survey

    PubMed Central

    Budenz, Donald L.; Bandi, Jagadeesh R.; Barton, Keith; Nolan, Winifred; Herndon, Leon; Whiteside-de Vos, Julia; Hay-Smith, Graham; Kim, Hanna; Tielsch, James

    2012-01-01

    Objective To determine the prevalence, etiologies, and risk factors of blindness and visual impairment among persons age 40 years and older residing in an urban West African location. Design Population-based cross-sectional study. Participants Five thousand six hundred and three participants residing in Tema, Ghana. Methods Proportionate random cluster sampling was used to select participants age 40 and over living in the city of Tema. Presenting distance visual acuity was measured at 4 and 1 meters using a reduced Logarithm of the Minimum Angle of Resolution (logMAR) tumbling E chart and then with trial frame based on autorefraction. A screening examination was performed in the field on all participants. Complete clinical examination by an ophthalmologist was performed on participants with best corrected visual acuity < 20/40 or failure of any screening test. Main Outcome Measures Age- and gender-specific prevalence, causes, and risk factors for blindness (visual acuity in the better eye of < 20/400, World Health Organization definition) and visual impairment (visual acuity in the better eye of < 20/40). Results Six thousand eight hundred and six eligible participants were identified of which 5603 (82.3%) participated in the study. The mean age (±standard deviation) of participants was 52.7±10.9. The prevalence of visual impairment was 17.1% and blindness was 1.2%. After refraction and spectacle correction, the prevalence of visual impairment and blindness decreased to 6.7% and 0.75% respectively, suggesting that refractive error is the major correctable etiology of visual impairment and blindness in this population. Of 65 subjects having visual acuity < 20/400, 22 (34%) were correctable with refraction, 21 to the level of visual impairment, and one to normal. The remaining 43 (66%) had underlying pathology (19 cataract, 9 glaucoma, 3 non-glaucomatous optic neuropathy, 3 corneal opacities, 3 retinal disease, 5 undetermined) that prevented refractive correction

  4. Mitigation of Disasters Due to Severe Climate Events: from Policy to Practice,the West African Coastal Region Experience

    NASA Astrophysics Data System (ADS)

    Ediang, Okuku

    2016-07-01

    The distributive pattern of disaster due to severe climate events over the coast of West Africa especially Nigeria was examined using yearly mean disaster due to severe climatic events for the period of 30 years (1981-2010) from the marine stations in the coastal region of Nigeria. Graphical and isohyetal analyses were used to look into the patter of severe weather events over the area considered and to see if the severe weather events is increasing or not in the coast of West Africa especially the Nigerian coast and how to mitigate ,were policy relating to severe weather events are discussed. The paper conclude that due to the nature of coast of West Africa and Nigeria in particular, it enjoys longer severe weather events season than dry during the wet season, it is common to observe periods of enhanced or suppressed convective activity to persist over the wide areas for somedays. This paper also contributes to the wealth of knowledge already existing on Indigenous people play major roles in preserving the ecosystem especially during severe weather events . This has resulted in the recent calls for the integration of indigenous knowledge systems into global knowledge system strategies. Until now, integrating local knowledge systems into severe weather events and climate change concerns is not a completely new idea. A comprehensive review of literature using electronic and non-electronic databases formed the methodology. The paper conclude also by drawing the attention that by targeting Promoting indigenous people's participation in severe weather events and climate change issues is an important initiative towards adaptation and sustainable development in Africa and around the world. It is increasingly realized that the global knowledge system has dominated research, policies and programmes that address current severe weather events and climate change's challenges,mitigation and adaptation strategies.

  5. Characteristics and phylogeny of Bacillus cereus strains isolated from Maari, a traditional West African food condiment.

    PubMed

    Thorsen, Line; Kando, Christine Kere; Sawadogo, Hagrétou; Larsen, Nadja; Diawara, Bréhima; Ouédraogo, Georges Anicet; Hendriksen, Niels Bohse; Jespersen, Lene

    2015-03-01

    Maari is a spontaneously fermented food condiment made from baobab tree seeds in West African countries. This type of product is considered to be safe, being consumed by millions of people on a daily basis. However, due to the spontaneous nature of the fermentation the human pathogen Bacillus cereus occasionally occurs in Maari. This study characterizes succession patterns and pathogenic potential of B. cereus isolated from the raw materials (ash, water from a drilled well (DW) and potash), seed mash throughout fermentation (0-96h), after steam cooking and sun drying (final product) from two production sites of Maari. Aerobic mesophilic bacterial (AMB) counts in raw materials were of 10(5)cfu/ml in DW, and ranged between 6.5×10(3) and 1.2×10(4)cfu/g in potash, 10(9)-10(10)cfu/g in seed mash during fermentation and 10(7) - 10(9) after sun drying. Fifty three out of total 290 AMB isolates were identified as B. cereus sensu lato by use of ITS-PCR and grouped into 3 groups using PCR fingerprinting based on Escherichia coli phage-M13 primer (M13-PCR). As determined by panC gene sequencing, the isolates of B. cereus belonged to PanC types III and IV with potential for high cytotoxicity. Phylogenetic analysis of concatenated sequences of glpF, gmk, ilvD, pta, pur, pycA and tpi revealed that the M13-PCR group 1 isolates were related to B. cereus biovar anthracis CI, while the M13-PCR group 2 isolates were identical to cereulide (emetic toxin) producing B. cereus strains. The M13-PCR group 1 isolates harboured poly-γ-D-glutamic acid capsule biosynthesis genes capA, capB and capC showing 99-100% identity with the environmental B. cereus isolate 03BB108. Presence of cesB of the cereulide synthetase gene cluster was confirmed by PCR in M13-PCR group 2 isolates. The B. cereus harbouring the cap genes were found in potash, DW, cooking water and at 8h fermentation. The "emetic" type B. cereus were present in DW, the seed mash at 48-72h of fermentation and in the final product

  6. Biodiversity Mapping in a Tropical West African Forest with Airborne Hyperspectral Data

    PubMed Central

    Vaglio Laurin, Gaia; Chan, Jonathan Cheung-Wai; Chen, Qi; Lindsell, Jeremy A.; Coomes, David A.; Guerriero, Leila; Frate, Fabio Del; Miglietta, Franco; Valentini, Riccardo

    2014-01-01

    Tropical forests are major repositories of biodiversity, but are fast disappearing as land is converted to agriculture. Decision-makers need to know which of the remaining forests to prioritize for conservation, but the only spatial information on forest biodiversity has, until recently, come from a sparse network of ground-based plots. Here we explore whether airborne hyperspectral imagery can be used to predict the alpha diversity of upper canopy trees in a West African forest. The abundance of tree species were collected from 64 plots (each 1250 m2 in size) within a Sierra Leonean national park, and Shannon-Wiener biodiversity indices were calculated. An airborne spectrometer measured reflectances of 186 bands in the visible and near-infrared spectral range at 1 m2 resolution. The standard deviations of these reflectance values and their first-order derivatives were calculated for each plot from the c. 1250 pixels of hyperspectral information within them. Shannon-Wiener indices were then predicted from these plot-based reflectance statistics using a machine-learning algorithm (Random Forest). The regression model fitted the data well (pseudo-R2 = 84.9%), and we show that standard deviations of green-band reflectances and infra-red region derivatives had the strongest explanatory powers. Our work shows that airborne hyperspectral sensing can be very effective at mapping canopy tree diversity, because its high spatial resolution allows within-plot heterogeneity in reflectance to be characterized, making it an effective tool for monitoring forest biodiversity over large geographic scales. PMID:24937407

  7. Fire Patterns and Drivers of Fires in the West African Tropical Forest

    NASA Astrophysics Data System (ADS)

    Dwomoh, F. K.; Wimberly, M. C.

    2015-12-01

    The West African tropical forest (referred to as the Upper Guinean forest, UGF), is a global biodiversity hotspot providing vital ecosystem services for the region's socio-economic and environmental wellbeing. It is also one of the most fragmented and human-modified tropical forest ecosystems, with the only remaining large patches of original forests contained in protected areas. However, these remnant forests are susceptible to continued fire-mediated degradation and forest loss due to intense climatic, demographic and land use pressures. We analyzed human and climatic drivers of fire activity in the sub-region to better understand the spatial and temporal patterns of these risks. We utilized MODIS active fire and burned area products to identify fire activity within the sub-region. We measured climatic variability using TRMM rainfall data and derived indicators of human land use from a variety of geospatial datasets. We used a boosted regression trees model to determine the influences of predictor variables on fire activity. Our analyses indicated that the spatial and temporal variability of precipitation is a key driving factor of fire activity in the UGF. Anthropogenic effects on fire activity in the area were evident through the influences of agriculture and low-density populations. These human footprints in the landscape make forests more susceptible to fires through forest fragmentation, degradation, and fire spread from agricultural areas. Forested protected areas within the forest savanna mosaic experienced frequent fires, whereas the more humid forest areas located in the south and south-western portions of the study area had fewer fires as these rainforests tend to offer some buffering against fire encroachment. These results improve characterization of UGF fire regime and expand our understanding of the spatio-temporal dynamics of tropical forest fires in response to human and climatic pressures.

  8. Effects of the environment on fish juvenile growth in West African stressful estuaries

    NASA Astrophysics Data System (ADS)

    Diouf, K.; Guilhaumon, F.; Aliaume, C.; Ndiaye, P.; Chi, T. Do; Panfili, J.

    2009-06-01

    The knowledge of juvenile fish growth in extreme environmental conditions is a key to the understanding of adaptive responses and to the relevant management of natural populations. The juvenile growth of an extreme euryhaline tilapia species, Sarotherodon melanotheron (Cichlidae), was examined across a salinity gradient (20-118) in several West African estuarine ecosystems. Juveniles were collected during the reproduction period of two consecutive years (2003 and 2004) in six locations in the Saloum (Senegal) and Gambia estuaries. Age and growth were estimated using daily otolith microincrements. For each individual, otolith growth rates showed three different stages (slow, fast, decreasing): around 4 ± 0.5 μm d -1 during the first five days, 9 ± 0.5 μm d -1 during the next 15 days and 4 ± 0.50 μm d -1 at 60 days. Growth modelling and model comparisons were objectively made within an information theory framework using the multi-model inference from five growth models (linear, power, Gompertz, von Bertalanffy, and logistic). The combination of both the model adjustment inspection and the information theory model selection procedure allowed identification of the final set of models, including the less parameterised ones. The estimated growth rates were variable across spatial scales but not across temporal scales (except for one location), following exactly the salinity gradient with growth decrease towards the hypersaline conditions. The salinity gradient was closely related to all measured variables (condition factor, mean age, multi-model absolute growth rate) demonstrating the strong effect of hypersaline environmental conditions—induced by climate changes—on fish populations at an early stage.

  9. Skill, reproducibility and potential predictability of the West African monsoon in coupled GCMs

    NASA Astrophysics Data System (ADS)

    Philippon, N.; Doblas-Reyes, F. J.; Ruti, P. M.

    2010-07-01

    In the framework of the ENSEMBLES FP6 project, an ensemble prediction system based on five different state-of-the-art European coupled models has been developed. This study evaluates the performance of these models for forecasting the West African monsoon (WAM) at the monthly time scale. From simulations started the 1 May of each year and covering the period 1991-2001, the reproducibility and potential predictability (PP) of key parameters of the WAM—rainfall, zonal and meridional wind at four levels from the surface to 200 hPa, and specific humidity, from July to September—are assessed. The Sahelian rainfall mode of variability is not accurately reproduced contrary to the Guinean rainfall one: the correlation between observations (from CMAP) and the multi-model ensemble mean is 0.17 and 0.55, respectively. For the Sahelian mode, the correlation is consistent with a low PP of about ~6%. The PP of the Guinean mode is higher, ~44% suggesting a stronger forcing of the sea surface temperature on rainfall variability over this region. Parameters relative to the atmospheric dynamics are on average much more skillful and reproducible than rainfall. Among them, the first mode of variability of the zonal wind at 200 hPa that depicts the Tropical Easterly Jet, is correlated at 0.79 with its “observed” counterpart (from the NCEP/DOE2 reanalyses) and has a PP of 39%. Moreover, models reproduce the correlations between all the atmospheric dynamics parameters and the Sahelian rainfall in a satisfactory way. In that context, a statistical adaptation of the atmospheric dynamic forecasts, using a linear regression model with the leading principal components of the atmospheric dynamical parameters studied, leads to moderate receiver operating characteristic area under the curve and correlation skill scores for the Sahelian rainfall. These scores are however much higher than those obtained using the modelled rainfall.

  10. Mutual interaction between the West African Monsoon on the summer Mediterranean climate

    NASA Astrophysics Data System (ADS)

    Gaetani, M.; Baldi, M.; Dalu, G. A.

    2009-04-01

    Many studies have show that the West African Monsoon (WAM) is teleconnected with neighbouring regions, as the Mediterranean (Med) basin and the Tropical Atlantic, but also it is sensitive to the perturbations occurring even in remote regions, as the Indian sub-continent and the Tropical Pacific, these teleconnections being active on several time-scales, from intraseasonal to multidecadal. The WAM plays also an active role in the regional atmospheric circulation, inducing significant changes in rainfall, moisture, temperature, and wind distribution up to the North Africa. Within this framework, recent works were focused on the teleconnection between WAM and Med. WAM is strengthened by the north-easterly advection of moisture from the Med Sea, and, since the subsiding monsoonal air often invades the Med, there is a 2-way interaction between WAM and Med summer circulation. We study these interactions, applying SVD analysis to global NCEP Reanalysis and to rainfall data from CMAP, during the extended monsoonal season from May to October, on interannual and on intraseasonal time-scale. Dynamical features are explored using composite analysis, focusing on the role of this connection in the heat waves occurrence in the Med. We find that a strong WAM intensifies the Hadley meridional circulation, with a strengthening of the north Atlantic anticyclone and a weakening, even blocking, of the westerly flow in the Med. A deep inland penetration of WAM produces a northern shift of the Libyan anticyclone, with subsidence and high pressure affecting mainly the western Med. The positive feedback is due to the intensification of north-easterly flow from the eastern Med, which, reaching the Sahara desert, intensifies the intertropical front, favouring abundant monsoonal precipitation because of the added moist air.

  11. Changes in intraseasonal characteristics of temperature and rainfall and their impacts on West African crops

    NASA Astrophysics Data System (ADS)

    Biasutti, M.; Lobell, D. B.

    2012-12-01

    The CMIP3 and CMIP5 models project that, by the end of the century, the western Sahel will see much higher temperatures, a later beginning of the rainy season, and more rainfall accumulation. All of these changes can have a substantial impact on agricultural output, as higher temperatures and late onset are expected to lower yields, but wetter conditions could ameliorate, or even reverse, such changes. To better quantify the overall impact of the projected climate on yields as well as its uncertainty, we need to understand the sensitivity of yields to each climatic factor. This, in turn, is likely to depend on how the mean changes are realized. For example, the mean temperature increase might be less important than the increased occurrence of heat waves, and the mean rainfall increase less important than the increase in the number of rainy days. We therefore (i) validate the CMIP5 historical simulations on both their seasonal mean fields and their intraseasonal characteristics of temperature and rainfall (such as heat wave occurrence, monsoon onset dates, and dry spells); and (ii) characterize the mean changes predicted for the end of the century in terms of their expression at intraseasonal timescales. Whether a climatic driver affects the aggregated agricultural output of West African countries (as opposed to the yield of a single agricultural field) depends on the level of large scale coherence in its variations. We therefore quantify the degree of spatial coherence in the variability of intraseasonal characteristics in both observations (from station and gridded data) and models. Finally, we analyze variations in yields of staple crops (sorghum and millet) at the province and country level and relate them to variations in climate parameters (seasonal means and intraseasonal characteristics).

  12. Transversal analysis of public policies on user fees exemptions in six West African countries

    PubMed Central

    2012-01-01

    Background While more and more West African countries are implementing public user fees exemption policies, there is still little knowledge available on this topic. The long time required for scientific production, combined with the needs of decision-makers, led to the creation in 2010 of a project to support implementers in aggregating knowledge on their experiences. This article presents a transversal analysis of user fees exemption policies implemented in Benin, Burkina Faso, Mali, Niger, Togo and Senegal. Methods This was a multiple case study with several embedded levels of analysis. The cases were public user fees exemption policies selected by the participants because of their instructive value. The data used in the countries were taken from documentary analysis, interviews and questionnaires. The transversal analysis was based on a framework for studying five implementation components and five actors’ attitudes usually encountered in these policies. Results The analysis of the implementation components revealed: a majority of State financing; maintenance of centrally organized financing; a multiplicity of reimbursement methods; reimbursement delays and/or stock shortages; almost no implementation guides; a lack of support measures; communication plans that were rarely carried out, funded or renewed; health workers who were given general information but not details; poorly informed populations; almost no evaluation systems; ineffective and poorly funded coordination systems; low levels of community involvement; and incomplete referral-evacuation systems. With regard to actors’ attitudes, the analysis revealed: objectives that were appreciated by everyone; dissatisfaction with the implementation; specific tensions between healthcare providers and patients; overall satisfaction among patients, but still some problems; the perception that while the financial barrier has been removed, other barriers persist; occasionally a reorganization of practices

  13. Ultrastructural observations on the terminal segment epithelium of the seminiferous tubule of West African dwarf goats.

    PubMed Central

    Ezeasor, D N

    1986-01-01

    In the testes of West African dwarf goats, modified Sertoli cells comprise the major component of the terminal segment epithelium. They resemble Sertoli cells proper but differ in the paucity of agranular endoplasmic reticulum and lipid droplets. Cell attachment devices present include rudimentary desmosomes and occasional multiple contacts of opposing plasma membranes, interrupted by segments of slightly expanded intercellular space. A few generative cells are present in the proximal zone of the epithelium, but their development appears to terminate as early spermatids which hang loosely on the luminal surface. The middle zone epithelium comprises vacuolated cells lying among other cells containing abundant microtubules in their subapical cytoplasm. Globular expansions of the intercellular space are also apparent. The terminal plug contains two cell types. Type I are inclined, columnar cells which contain profuse arrays of agranular endoplasmic reticulum in their apical cytoplasm. Type II are smaller cells located at the apex of the plug. Each possesses cytoplasmic processes, which surround the apices of Type I cells. The modified Sertoli cells of all zones and the Type II plug cells contain remnants of spermatozoa at different stages of degradation. The general absence of developing generative cells in the terminal segment epithelium may be related to the paucity of agranular endoplasmic reticulum in the basal cytoplasm of modified Sertoli cells and the absence of typical Sertoli-Sertoli junctional specialisations. Structural modifications evident in the middle and distal zones facilitate distalward movement of materials, while the attenuation and modification of the lumen distally may facilitate phagocytosis of abnormal spermatozoa. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Fig. 12 PMID:3693043

  14. Phylogeography of the Afromontane Prunus africana reveals a former migration corridor between East and West African highlands.

    PubMed

    Kadu, C A C; Schueler, S; Konrad, H; Muluvi, G M M; Eyog-Matig, O; Muchugi, A; Williams, V L; Ramamonjisoa, L; Kapinga, C; Foahom, B; Katsvanga, C; Hafashimana, D; Obama, C; Geburek, T

    2011-01-01

    Scattered populations of the same tree species in montane forests through Africa have led to speculations on the origins of distributions. Here, we inferred the colonization history of the Afromontane tree Prunus africana using seven chloroplast DNA loci to study 582 individuals from 32 populations sampled in a range-wide survey from across Africa, revealing 22 haplotypes. The predominant haplotype, HT1a, occurred in 13 populations of eastern and southern Africa, while a second common haplotype, HT1m, occurred in populations of western Uganda and western Africa. The high differentiation observed between populations in East Africa was unexpected, with stands in western Uganda belonging with the western African lineage. High genetic differentiation among populations revealed using ordered alleles (N(ST) = 0.840) compared with unordered alleles (G(ST) = 0.735), indicated a clear phylogeographic pattern. Bayesian coalescence modelling suggested that 'east' and 'west' African types likely split early during southward migration of the species, while further more recent splitting events occurred among populations in the East of the continent. The high genetic similarity found between western Uganda and west African populations indicates that a former Afromontane migration corridor may have existed through Equatorial Africa.

  15. Assessment of contamination, distribution and chemical speciation of trace metals in water column in the Dakar coast and the Saint Louis estuary from Senegal, West Africa.

    PubMed

    Diop, Cheikh; Dewaelé, Dorothée; Diop, Mamadou; Touré, Aminata; Cabral, Mathilde; Cazier, Fabrice; Fall, Mamadou; Diouf, Amadou; Ouddane, Baghdad

    2014-09-15

    The water column from Dakar coast and Saint Louis estuary in Senegal, West Africa, was sampled in order to measure the contamination level by trace metals. The speciation of metals in water allowed performing a distribution between dissolved and particulate trace metals. For the dissolved metals, the metallic concentration and repartition between the organic fraction and the inorganic fraction were performed. The results show that the pollution of the estuary was more serious than in Dakar coast for Co, Cr, Ni, Pb and Zn; while, Cd and Cu were higher in Dakar coast. A strong affinity between metals and suspended particles has been revealed. Dissolved metals that have a tendency to form organic metal complexes are in decreasing order: Cd, Zn, Pb, Co=Cr=Mn, Cu and Ni. The results showed that the mobility of trace metals in estuary is controlled by dissolved organic carbon, while in coast it depends on chlorides.

  16. Forecasting cyclic coastal erosion on a multi-annual to multi-decadal scale: Southeast African coast

    NASA Astrophysics Data System (ADS)

    Smith, A. M.; Guastella, L. A.; Botes, Z. A.; Bundy, S. C.; Mather, A. A.

    2014-10-01

    Coastal erosion on the southeast African coastline shows an apparent 18 year cycle which last peaked in 2006. It is in phase with the longshore sediment transport cycle. Both these cycles appear to be in phase with the Lunar Nodal Cycle (LNC). However, the dominant tidal erosion driver on this coast appears to be the 4.4 year Lunar Perigean Subharmonic (LPS). We suggest that the apparent 18 year coastal erosion and longshore sediment budget cycle is a response to the 18 year Mean Annual Precipitation Cycle. This cycle is 180° out of phase with the apparent coastal erosion- and longshore sediment transport- cycles. The summer rainfall areas, of southeastern Africa show an 18 year MAP cyclicity, which drives river runoff and hence controls sediment input to the coast and nearshore environment. The MAP cycle dominates the coastal sediment budget during the LNC trough and suppresses the LPS coastal erosion cycle during this time. This explains why LPS coastal erosion occurs close to the LNC peak. Thus although the LPS cycle dominates the coastline, it is masked during the wet portion of the 18 year MAP cycle. It seems very likely that the LNC drives the MAP cycle in some way but this process is not known. Nevertheless, these relationships can be used to predict, in a general way, both cyclic coastal erosion and the longshore sediment volume fluctuation. This can be translated into a vital coastal planning tool which has the potential to forecast cyclic coastal erosion and hence significantly reduce the sea-defense expenditure bill. Based on this, severe cyclic coastal erosion is anticipated in 2023 and 2024.

  17. Has the middle-level anaesthesia manpower training program of the West African College of Surgeons fulfilled its objectives?

    PubMed

    Bode, C O; Olatosi, J; Amposah, G; Desalu, I

    2013-05-01

    An audit of the West African College of Surgeons' middle-level Diploma in Anaesthesia program was carried out to determine the current status of the diplomates. Using the West African College of Surgeons' database, social media and personal communications, the current status of Diploma in Anaesthesia graduates spanning 20 years was determined. A total of 303 (97%) out of 311 of graduates were traced. Eighty percent were still practising anaesthesia, while 5% were now in other disciplines. Two hundred and four (67.3%) still resided in West Africa (183 in Nigeria, 50 in Ghana, one in Sierra Leone), while 69 (22.7%) were abroad: 35 (11.5%) in the United Kingdom, 21 (6.9%) in the United States of America and four (1.3%) in Canada. More Ghanaian than Nigerian graduates had emigrated (41 vs 14%, respectively). Only 9% of diplomates remained in rural communities (as originally envisaged), while 31% were now consultants (as fellows) and 30% were registrars in fellowship training. These findings indicate that most diplomates moved on to acquire further qualifications and a significant proportion migrated. The program did not appear to have achieved the objectives of meeting rural middle-level manpower needs in anaesthesia as envisaged. It has, however, boosted the recruitment drive for residency training in anaesthesia. Perhaps a less migrant cadre such as nurses may better serve this function if recruited into a suitably designed training program in countries desiring to use middle-level manpower in anaesthesia.

  18. 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

  19. The impact of the 2009-10 El Niño on West Coast beaches

    NASA Astrophysics Data System (ADS)

    Barnard, P.; Kaminsky, G. M.; Hansen, J. E.; Allan, J. C.; Ruggiero, P.; Hoover, D. J.

    2010-12-01

    Long-term monitoring programs at a series of beaches in California, Oregon and Washington were used to evaluate beach evolution associated with the El Niño winter of 2009-10, and to relate the observed coastal change to past winters, including the last major El Niño in 1997-98. At the California study sites, analysis of Lidar (1997-98) and semi-annual or greater high-resolution beach and nearshore surveys (2004-10) shows that coastal change during the winter of 2009-10 broadly rivals that in 1997-98, and that the 2009-10 winter storms collectively forced the most beach erosion since high-resolution monitoring began in 2004. Along the Oregon and Washington coasts, many beaches exhibited classic El Niño shoreline responses, with significant shoreline retreat occurring immediately north of jetties and tidal inlets as well as the southern ends of pocket beaches and littoral cells. In Washington in particular, these areas eroded rapidly during the winter of 2009-10, comparable to the response seen in the El Niño winter of 1997-98. Wave buoy data from buoys in California and Washington that captured both the 1997-98 and 2009-10 El Niño show that the two events were comparable in wave energy as measured by the mean wave year (1 July- 30 June) energy flux (Fig. 1). The increased wave energy in 2009-10 had significant impacts on coastal infrastructure throughout the region; for example, in San Francisco the Great Highway was severely undercut by wave action, resulting in a $5 million emergency remediation project. In Washington, approximately 195 m of road was eroded along the entrance to Willapa Bay and southern Grayland Plains. While the impacts of the 2009-10 winter were substantial, impacts on the coast were moderated by an unusually mild wave climate in 2008-9 (Fig. 1), which left beaches more accreted prior to the severe wave season of 2009-10. As climate change accelerates sea level rise and potentially increases the magnitude and frequency of storms in mid

  20. Blended sea level anomaly fields with enhanced coastal coverage along the U.S. West Coast.

    PubMed

    Risien, C M; Strub, P T

    2016-01-01

    We form a new 'blended' data set of sea level anomaly (SLA) fields by combining gridded daily fields derived from altimeter data with coastal tide gauge data. Within approximately 55-70 km of the coast, the altimeter data are discarded and replaced by a linear interpolation between the tide gauge and remaining offshore altimeter data. To create a common reference height for altimeter and tide gauge data, a 20-year mean is subtracted from each time series (from each tide gauge and altimeter grid point) before combining the data sets to form a blended mean sea level anomaly (SLA) data set. Daily mean fields are produced for the 22-year period 1 January 1993-31 December 2014. The primary validation compares geostrophic velocities calculated from the height fields and velocities measured at four moorings covering the north-south range of the new data set. The blended data set improves the alongshore (meridional) component of the currents, indicating an improvement in the cross-shelf gradient of the mean SLA data set. PMID:26927667

  1. Blended sea level anomaly fields with enhanced coastal coverage along the U.S. West Coast.

    PubMed

    Risien, C M; Strub, P T

    2016-03-01

    We form a new 'blended' data set of sea level anomaly (SLA) fields by combining gridded daily fields derived from altimeter data with coastal tide gauge data. Within approximately 55-70 km of the coast, the altimeter data are discarded and replaced by a linear interpolation between the tide gauge and remaining offshore altimeter data. To create a common reference height for altimeter and tide gauge data, a 20-year mean is subtracted from each time series (from each tide gauge and altimeter grid point) before combining the data sets to form a blended mean sea level anomaly (SLA) data set. Daily mean fields are produced for the 22-year period 1 January 1993-31 December 2014. The primary validation compares geostrophic velocities calculated from the height fields and velocities measured at four moorings covering the north-south range of the new data set. The blended data set improves the alongshore (meridional) component of the currents, indicating an improvement in the cross-shelf gradient of the mean SLA data set.

  2. Blended sea level anomaly fields with enhanced coastal coverage along the U.S. West Coast

    PubMed Central

    Risien, C.M.; Strub, P.T.

    2016-01-01

    We form a new ‘blended’ data set of sea level anomaly (SLA) fields by combining gridded daily fields derived from altimeter data with coastal tide gauge data. Within approximately 55–70 km of the coast, the altimeter data are discarded and replaced by a linear interpolation between the tide gauge and remaining offshore altimeter data. To create a common reference height for altimeter and tide gauge data, a 20-year mean is subtracted from each time series (from each tide gauge and altimeter grid point) before combining the data sets to form a blended mean sea level anomaly (SLA) data set. Daily mean fields are produced for the 22-year period 1 January 1993–31 December 2014. The primary validation compares geostrophic velocities calculated from the height fields and velocities measured at four moorings covering the north-south range of the new data set. The blended data set improves the alongshore (meridional) component of the currents, indicating an improvement in the cross-shelf gradient of the mean SLA data set. PMID:26927667

  3. Distribution and character of upper mesozoic subduction complexes along the west coast of North America

    USGS Publications Warehouse

    Jones, D.L.; Blake, M.C.; Bailey, E.H.; McLaughlin, R.J.

    1978-01-01

    Structurally complex sequences of sedimentary, volcanic, and intrusive igneous rocks characterize a nearly continuous narrow band along the Pacific coast of North America from Baja California, Mexico to southern Alaska. They occur in two modes: (1) as complexly folded but coherent sequences of graywacke and argillite that locally exhibit blueschist-grade metamorphism, and (2) as melanges containing large blocks of graywacke, chert, volcanic and plutonic rocks, high-grade schist, and limestone in a highly sheared pelitic, cherty, or sandstone matrix. Fossils from the coherent graywacke sequences range in age from late Jurassic to Eocene; fossils from limestone blocks in the melanges range in age from mid-Paleozoic to middle Cretaceous. Fossils from the matrix surrounding the blocks, however, are of Jurassic, Cretaceous, and rarely, Tertiary age, indicating that fossils from the blocks cannot be used to date the time of formation of the melanges. Both the deformation of the graywacke, with accompanying blueschist metamorphism, as well as the formation of the melanges, are believed to be the result of late Mesozoic and early Tertiary subduction. The origin of the melanges, particularly the emplacement of exotic tectonic blocks, is not understood. ?? 1978.

  4. Stratigraphic evidence for earthquakes and tsunamis on the west coast of South Andaman Island, India during the past 1000 years

    NASA Astrophysics Data System (ADS)

    Malik, Javed N.; Banerjee, Chiranjib; Khan, Afzal; Johnson, Frango C.; Shishikura, Masanobu.; Satake, Kenji.; Singhvi, Ashok K.

    2015-10-01

    Stratigraphic records from west coast of South Andaman Island revealed evidence of three historical earthquakes and associated transoceanic tsunamis during past 1000 yrs, in addition to the Mw 9.3 tsunamigenic earthquake of 26 December, 2004. Our finding suggests that along with Sumatran arc segment the Andaman-Arakan segment is also capable of generating mega-subduction zone earthquakes and transoceanic tsunamis. To study the near sub-surface stratigraphic succession we excavated shallow trenches and obtained geoslices from two sites around Collinpur (sites 1 and 2). The exposed succession comprised 11 lithounits (Unit a - youngest and k - oldest) of alternating sequence of coarser units overlain by peaty soils and some of these are indicative of deposition during paleo-tsunami events. Event I that predated AD 800, and is marked by a 35-40 cm thick deposit of fine gravel to coarse sands along with broken shell fragments (Unit k). Event II dated around AD 660-800, is represented by 20-25 cm thick coarse sand and broken shell fragments (Unit i). Based on stratigraphic evidences of land-level changes, this event is attributed to a near source rupture along Andaman-Arakan segment, accompanied by a transoceanic tsunami. Event III, occurred around AD 1120-1300, is marked by a 50 cm thick sand deposit (Unit g). The 2004 tsunami resulted in deposition of 15 cm thick medium to coarse sand at the same location. We infer that the 2004 tsunami and Event III resulted in different styles of sedimentation at the same site. Four events at Collinpur along with the record of a subsidence event of AD 1679 from the east coast of Andaman, close-to, Port Blair (Malik et al., 2011), suggest that mega-subduction zone earthquakes and associated tsunamis recur at an interval of 300-500 years at variable locations along the Sumatra-Andaman subduction zone.

  5. [Abundance of sea urchin Lytechinus variegatus (Lamarck) on North, East and West coasts of Margarita Island (Venezuela) ].

    PubMed

    Gómez Gaspar, Alfredo

    2002-01-01

    The sea urchin roe reach a very high price in the international fish product market favoring the increase in the catches of this resource and overfishing in some countries. In the Island of Margarita (Venezuela) some species, Lytechinus variegatus (Lamarck) among others, are consumed as food but studies to determine abundance of the resource are unknown. Nine sample stations (depth less than 2 m) on the North, East and West coast of Margarita Island were visited in six different occasions between February/1998 and February/1999 to study the population density (urchins/m2) of L. variegatus. Using a quadrat (0.25 m2) thrown 8 times over seagrasses (Thalassia testudinum) beds and over submerged rocks and the urchins removed by dive. The diameter of each specimen was measured and returned to the sea. The water temperature, salinity and dissolved oxygen of each site was measured. Were collected a total of 2,073 urchins with a diameter ranging from 11.0 to 84.5 mm and population density between 1 to 52 urchins/m2. The mean size of specimens collected in the stations was between 30.44 and 55.09 mm and average density fluctuated between 3.2 to 43.2 urchins/m2. The station where sea urchins were found to be most abundant was the North coast (Manzanillo fishing villae) where they live on rocks with a density (38 a 52/m2) far over the values previously cited for the Caribbean sea and Florida.

  6. Seal dynamics on the Swedish west coast: Scenarios of competition as Baltic grey seal intrude on harbour seal territory

    NASA Astrophysics Data System (ADS)

    Svensson, Carl Johan

    2012-07-01

    The Kattegat-Skagerrak region on the Swedish west coast is home to an abundant harbour seal population (Phoca vitulina) and a small scattered grey seal population (Halichoerus grypus). In addition, grey seal from the growing population in the Baltic Sea frequently migrate into the Kattegat-Skagerrak. Harbour seals on the west coast of Sweden show relatively high population growth (approximately 9%) compared to the Baltic grey seal in ice-free habitats (approximately 6%), which, in theory, makes harbour seal the stronger competitor of the two in this region. However, incidents of disease in harbour seals that lower population growth are becoming more frequent. These epidemics are primarily caused by the Phocine Distemper Virus (PDV), and may reduce population size with up to 70%. This study models the average development under potential scenarios of competing harbour- and Baltic grey seal populations using Leslie matrices and the Lotka-Volterra model of inter-specific competition. The model is parameterised with previously published data, and resource overlap is incorporated through density dependent pup survival. Using numerical methods short- and long-term abundances are simulated under weak, moderate and strong competition and for different frequencies of PDV epidemics. Results show that the harbour seals are resilient to competition while exerting a negative effect on grey seal abundance under moderate to strong competition. Hence Baltic grey seal benefit from weaker levels of competition. Under moderate and strong competition grey seal abundance is a direct function of the PDV frequency as this reduces the competitive strength of harbour seals. Theoretically this means that higher frequencies of PDV or other pathogens epidemics could facilitate an expansion of Baltic grey seal into Kattegat-Skagerrak. Independent of interaction strength and frequency of epidemics the projected changes to abundances are slow (50-100 years), and even in exceedingly stable

  7. Variability in growth, development and reproduction of the non-native seaweed Sargassum muticum (Phaeophyceae) on the Irish west coast

    NASA Astrophysics Data System (ADS)

    Baer, Julia; Stengel, Dagmar B.

    2010-12-01

    This study compared seasonal growth, development and reproduction of the invasive brown macroalga Sargassum muticum in habitats with different wave exposure on the Irish west coast. Three field sites with different degrees of wave exposure were chosen for monthly observations to reflect different habitats that were characteristic of the Irish west coast. Growth and receptacle development differed considerably between sites. Growth and receptacle development was lower at the most sheltered site. Here, S. muticum showed signs of early fragmentation in April/May during the two years of investigation (2007 and 2008), whilst the population at an exposed site developed normally and plants grew to a maximum average length of 163 cm by July, with the onset of fragmentation in August. Sargassum muticum in a tide pool exhibited a similar seasonal growth cycle as plants at the exposed open shore site. Overall growth however was stunted, with plants reaching a maximum length of only 30-40 cm in July. Receptacle development was also inhibited at the sheltered site, with a maximum of only 10% of plants found to be fertile during spring and summer 2008, while plants at the exposed site and the tide pool exhibited 100% plant fertility by August. An extensive occurrence of the native epiphyte Pylaiella littoralis on S. muticum was noticed during field sampling at the sheltered study site which may have contributed to inhibited development of S. muticum observed in this area. Seasonal biomass production, photosynthetic activity and plant/frond ratio development were contrasted between Sargassum muticum at the open shore and the tide pool. Sargassum muticum biomass production in the tide pool was 3.5 times lower than that of plants on the open shore. Receptacle development and seasonal photosynthetic activity were similar for tide pool and open shore plants, irrespective of morphological differences. Highest photosynthetic rates (fluorescence yield, Yo) were measured during active

  8. Recent deformation along the offshore Malibu Coast, Dume, and related faults west of Point Dume, southern California

    USGS Publications Warehouse

    Fisher, M.A.; Langenheim, V.E.; Sorlien, C.C.; Dartnell, P.; Sliter, R.W.; Cochrane, G.R.; Wong, F.L.

    2005-01-01

    Offshore faults west of Point Dume, southern California, are part of an important regional fault system that extends for about 206 km, from near the city of Los Angeles westward along the south flank of the Santa Monica Mountains and through the northern Channel Islands. This boundary fault system separates the western Transverse Ranges, on the north, from the California Continental Borderland, on the south. Previous research showed that the fault system includes many active fault strands; consequently, the entire system is considered a serious potential earthquake hazard to nearby Los Angeles. We present an integrated analysis of multichannel seismic- and high-resolution seismic-reflection data and multibeam-bathymetric information to focus on the central part of the fault system that lies west of Point Dume. We show that some of the main offshore faults have cumulative displacements of 3-5 km, and many faults are currently active because they deform the seafloor or very shallow sediment layers. The main offshore fault is the Dume fault, a large north-dipping reverse fault. In the eastern part of the study area, this fault offsets the seafloor, showing Holocene displacement. Onshore, the Malibu Coast fault dips steeply north, is active, and shows left-oblique slip. The probable offshore extension of this fault is a large fault that dips steeply in its upper part but flattens at depth. High-resolution seismic data show that this fault deforms shallow sediment making up the Hueneme fan complex, indicating Holocene activity. A structure near Sycamore knoll strikes transversely to the main faults and could be important to the analysis of the regional earthquake hazard because the structure might form a boundary between earthquake-rupture segments.

  9. Identifying the source of tar balls deposited along the beaches of Goa in 2013 and comparing with historical data collected along the West Coast of India.

    PubMed

    Suneel, V; Vethamony, P; Naik, B G; Krishna, M S; Jadhav, Lakshmikant

    2015-09-15

    Deposition of oil residues, also known as tar balls, is a seasonal phenomenon, and it occurs only in the southwest monsoon season along the west coast of India. This has become a serious environmental issue, as Goa is a global tourist destination. The present work aims at identifying the source oil of the tar balls that consistently depositing along the Goa coast using multi-marker fingerprint technique. In this context, the tar ball samples collected in May 2013 from 9 beaches of Goa coast and crude oils from different oil fields and grounded ship were subject to multi-marker analyses such as n-alkanes, pentacyclic terpanes, regular steranes, compound specific isotope analysis (CSIA) and principle component analysis (PCA). The n-alkane weathering index shows that samples have been weathered to various degrees, and the status of weathering is moderate. Since the international tanker route passes closer to the west coast of India (WCI), it is generally presumed that tanker wash is the source of the tar balls. We found that 2010/2011 tar balls are as tanker wash, but the present study demonstrates that the Bombay High (BH) oil fields can also contribute to oil contamination (tar balls) along ≈ 650 km stretch of the WCI, running from Gujarat in the north to Goa in the south. The simulated trajectories show that all the particles released in April traveled in the southeast direction, and by May, they reached the Goa coast with the influence of circulation of Indian monsoon system.

  10. Differential opening of the Central and South Atlantic Oceans and the opening of the West African rift system

    NASA Astrophysics Data System (ADS)

    Fairhead, J. D.; Binks, R. M.

    1991-02-01

    Plate tectonic studies of the development of the Central and South Atlantic Oceans using Seasat and Geosat altimeter and magnetic anomaly isochron data now provide quantitative models of seafloor spreading through time. Such models enable an initial assessment of the differential opening between these two oceanic basins to be determined. The Equatorial Atlantic is an integral part of this oceanic rifting process, allowing stresses arising from the differential opening to be dissipated into both the Caribbean and Africa along its northern and southern boundaries respectively. The tectonic model for the West African rift system, based on geological and geophysical studies, shows a series of strike-slip fault zones diverging into Africa from the Gulf of Guinea and dissipating their shear movement into the development of extensional basins orientated perpendicular to these faults zones. The development of the West African rift system was contemporaneous with the early opening of the South Atlantic, continued to develop well after the final breakup of South America from Africa and did not cease until the late Cretaceous when there was a major phase of basin inversion and deformation. Santonian ( ~ 80 Ma) deformation across the Benue Trough (Nigeria) is broadly contemporaneous with dextral shear reactivation of the central African fracture system which, in turn resulted in renewed extension in the Sudan basins during the late Cretaceous and early Tertiary. This paper illustrates the close linkage in both time and space between the history of the African rift basins and the opening of the Atlantic. Both exhibit distinct phases of evolution with the rift basins developing in direct response to the differential opening between the Central and South Atlantic in order to dissipate stresses generated by this opening. The Mesozoic tectonic model proposed is therefore one of an intimate interaction between oceanic and continental tectonics.

  11. [Smoking in the African setting (Abidjan, Ivory coast): patient knowledge, attitude and behavior].

    PubMed

    Koffi, N; Kouassi, B; Horo, K; Kouakou, Y G M; N'Gom, A; Toloba, Y; Bouzid, S; Aka-Danguy, E

    2004-09-01

    Recent studies on smoking conducted in the ivory coast have been sparse despite increasingly aggressive tobacco company campaigns. The purpose of this prospective study was to examine the influence of medical specialty on patient knowledge, attitude and smoking behavior among people consulting three university hospitals in Abidjan. The inquiry was performed with a questionnaire concerning a comparative series of 180 subjects (90 patients in each sample). Overall, the series included 16.10% active smokers, 15.60% former smokers, and 68.30% non-smokers, with no difference between the groups. The well-known feature of smoking with friends was main reason cited for beginning smoking. Three quarters of patients (75.9%) had attempted to stop smoking. Information about smoking was obtained from the media. The hospital was involved little in acquiring knowledge about smoking. Type of specialist consultation (hospital units providing care for smoking-related disease or not) had little influence. Hospital units should become more involved in the anti-smoking campaign. Consultations on cessation of smoking should be instituted in a country with highly aggressive smoking advertisements.

  12. Rapid erosion of the coast of Sagar island, West Bengal - India

    NASA Astrophysics Data System (ADS)

    Gopinath, Girish; Seralathan, P.

    2005-10-01

    The coastal zone of the Sagar island has been studied. The island has been subjected to erosion by natural processes and to a little extent by anthropogenic activities over a long period. Major landforms identified in the coastal area of the Sagar island are the mud flats/salt marshes, sandy beaches/dunes and mangroves. The foreshore sediments are characterized by silty, slightly sandy mud, slightly silty sand and silty sand. Samples 500 m inland from high waterline are silty slightly sandy mud, and by clayey slightly sandy mud. The extent of coastline changes are made by comparing the topographic maps of 1967 and satellite imageries of 1996, 1998 and 1999. Between 1967 and 1999 about 29.8 km2 of the island has been eroded and the accreted area is only 6.03 km2. Between 1996 and 1998 the area underwent erosion of 13.64 km2 while accretion was 0.48 km2. From 1998 to 1999, 3.26 km2 additional area was eroded with meager accretion. Erosion from 1997 to 1999 was estimated at 0.74 km2 /year; however, from 1996 to 1999, the erosion rate was calculated as 5.47 km2/year. The areas severely affected by erosion are the northeastern, southwestern and southeastern faces of the island. As a consequence of coastal erosion, the mud flats/salt marshes, sandy beaches/dunes and mangroves have been eroded considerably. Deposition is experienced mainly on the western and southern part of the island. The island is built primarily by silt and clay, which can more easily be eroded by the waves, tides and cyclonic activities than a sandy coast. Historic sea level rises accompanied by land subsidence lead to differing rates of erosion at several pockets, thus periodically establishing new erosion planes.

  13. Potential Sedimentary Evidence of Two Closely Spaced Tsunamis on the West Coast of Aceh, Indonesia

    NASA Astrophysics Data System (ADS)

    Monecke, Katrin; Meilianda, Ella; Rushdy, Ibnu; Moena, Abudzar; Yolanda, Irvan P.

    2016-04-01

    Recent research in the coastal regions of Aceh, Indonesia, an area that was largely affected by the 2004 Sumatra Andaman earthquake and ensuing Indian Ocean tsunami, suggests the possibility that two closely spaced tsunamis occurred at the turn of the 14th to 15th century (Meltzner et al., 2010; Sieh et al., 2015). Here, we present evidence of two buried sand layers in the coastal marshes of West Aceh, possibly representing these penultimate predecessors of the 2004 tsunami. We discovered the sand layers in an until recently inaccessible area of a previously studied beach ridge plain about 15 km North of Meulaboh, West Aceh. Here, the 2004 tsunami left a continuous, typically a few cm thick sand sheet in the coastal hinterland in low-lying swales that accumulate organic-rich deposits and separate the sandy beach ridges. In keeping with the long-term progradation of the coastline, older deposits have to be sought after further inland. Using a hand auger, the buried sand layers were discovered in 3 cores in a flooded and highly vegetated swale in about 1 km distance to the shoreline. The pair of sand layers occurs in 70-100 cm depth and overlies 40-60 cm of dark-brown peat that rests on the basal sand of the beach ridge plain. The lower sand layer is only 1-6 cm thick, whereas the upper layer is consistently thicker, measuring 11-17 cm, with 8-14 cm of peat in between sand sheets. Both layers consist of massive, grey, medium sand and include plant fragments. They show very sharp upper and lower boundaries clearly distinguishing them from the surrounding peat and indicating an abrupt depositional event. A previously developed age model for sediments of this beach ridge plain suggest that this pair of layers could indeed correlate to a nearby buried sand sheet interpreted as tsunamigenic and deposited soon after 1290-1400AD (Monecke et al., 2008). The superb preservation at this new site allows the clear distinction of two depositional events, which, based on a first

  14. GLORIA mosaic of west coast U. S. Exclusive Economic Zone, southern sector

    SciTech Connect

    Gardner, J.V.; Edwards, B.D.; Field, M.E.; McCulloch, D.S.; Kenyon, N.H.; Masson, D.G.

    1986-05-01

    The long-range side-scan sonar system GLORIA was used to produce digitally enhanced mosaics of the sea floor of the entire US Exclusive Economic Zone. The data resolution, about 50 x 50 m, provides a mesoscale reconnaissance that reveals the continuity and extent of bottom features, some of which were previously unrecognized. The transform continental margin from the Mendocino Escarpment to the US-Mexican border is cut by numerous submarine canyons and gullies of varied size and complexity. The number, size, and extent of gullies appear directly related to the underlying bed-rock geology. Surprisingly, relatively few slumps and slump scarps are apparent. Submarine fans characterize the basins adjacent to the margin in this sector. The fans vary in size and complexity: relatively small, immature fans of the borderland basins, such as Redondo and Hueneme; fans intermediate in size and age, such as Arguello and Farallon; and large, relatively mature fans, such as Monterey and Delgada. Most fans have well-defined depositional lobes at the distal reach of a single channel. Distributary channels are not apparent on all fans, and on some (e.g., Monterey Fan), the single channel can be seen in seismic reflection profiles to have originated on or close to the basement, directly below its present position. The older depositional lobes that have been identified on the fan systems are adjacent to the present main channel, which implies that channel avulsion is not always a process that accompanies fan growth. Seamounts are prominent features in the region, ranging in number from hundreds in the Baja Seamount province to tens in the region west of San Francisco. The gradient of increasing numbers of exposed seamounts and volcanic ridges from north to south is a direct result of decreasing sediment supply from the continent to the south.

  15. Reproduction in the sea pen Funiculina quadrangularis (Anthozoa: Pennatulacea) from the west coast of Scotland

    NASA Astrophysics Data System (ADS)

    Edwards, Daniel C. B.; Moore, Colin G.

    2009-03-01

    The sea pen Funiculina quadrangularis (Pallas, 1766) is a species of conservation concern in Scottish coastal waters, due to its restricted geographical distribution and high sensitivity to demersal fishing activities. Reproduction in F. quadrangularis was investigated in a population located in southern Loch Linnhe, west Scotland. This was accomplished through the analysis of trends in oocyte size-frequency distribution and relative fecundity over a 12-month period. Funiculina quadrangularis is dioecious and the study population exhibited a sex ratio of 1:1. Oogenesis in female F. quadrangularis is characterised by the maintenance of a large pool of asynchronously developing oocytes throughout the year, of which a small proportion (<10%) mature with increasing sychronicity and are spawned in midwinter. The reasons for this distinct pattern of oogenesis and winter spawning remain unclear, although the potential influence of environmental cues and the role of endogenous factors in relation to this sea pen's deep-sea habit are discussed. Whilst the duration of oogenesis is prolonged (>12 months), it is proposed that spawning is a brief and synchronous annual event. Relative fecundity is high and is independent of colony size, varying between approximately 500-2000 oocytes per 1 cm rachial midsection. This measure of fecundity exhibited pronounced seasonality and was significantly lower during the post-spawning winter months. Total fecundity in F. quadrangularis is considered to be high; although a small proportion of the total number of oocytes is spawned annually, this is compensated for by large colony size. Funiculina quadrangularis produces large oocytes (>800 μm), indicative of the production of lecithotrophic larvae.

  16. Lysosomal responses and metallothionein induction in the blue mussel Mytilus edulis from the south-west coast of Iceland.

    PubMed

    Da Ros, L; Moschino, V; Guerzoni, S; Halldórsson, H P

    2007-04-01

    It has recently been emphasized that high levels of inorganic and organic micropollutants (particularly organometals, POPs and PAHs) may be present in coastal waters at high latitudes, stressing the need to evaluate the effects of contaminants on marine organisms from sub-arctic zones. With this aim, specimens of the blue mussel Mytilus edulis were sampled in polluted and reference areas along the south-west coast of Iceland in July 2004. Samples were collected from the intertidal zone at three sites in Reykjavik harbour which are differently exposed to contaminants, and at three reference coastal sites, two located along the Reykjanes Peninsula and the third one on the northern part of Hvalfjordur fiord. Lipofuscin content, neutral lipid accumulation and lysosomal enlargement were evaluated in digestive cells from cryostat sections of the mussel hepatopancreas, and quantified by automated image analysis. Metallothionein induction was also determined in the same tissue. Results indicate that mussels from the inner part of Reykjavik harbour, which is the most sheltered and most influenced by extensive shipping traffic, were the worst affected, with the highest values in neutral lipids, lipofuscin and lysosomal swelling. At the other two harbour sites, mussels exhibited lower values, similar to those observed in organisms collected in Hvalfjordur fiord and in bay of Osar. Mussels from Kuagerdi had the lowest values. PMID:17215043

  17. A possible transoceanic tsunami directed toward the U.S. west coast from the Semidi segment, Alaska convergent margin

    NASA Astrophysics Data System (ADS)

    von Huene, Roland; Miller, John J.; Dartnell, Peter

    2016-03-01

    The Semidi segment of the Alaska convergent margin appears capable of generating a giant tsunami like the one produced along the nearby Unimak segment in 1946. Reprocessed legacy seismic reflection data and a compilation of multibeam bathymetric surveys reveal structures that could generate such a tsunami. A 200 km long ridge or escarpment with crests >1 km high is the surface expression of an active out-of-sequence fault zone, recently referred to as a splay fault. Such faults are potentially tsunamigenic. This type of fault zone separates the relatively rigid rock of the margin framework from the anelastic accreted sediment prism. Seafloor relief of the ridge exceeds that of similar age accretionary prism ridges indicating preferential slip along the splay fault zone. The greater slip may derive from Quaternary subduction of the Patton Murray hot spot ridge that extends 200 km toward the east across the north Pacific. Estimates of tsunami repeat times from paleotsunami studies indicate that the Semidi segment could be near the end of its current inter-seismic cycle. GPS records from Chirikof Island at the shelf edge indicate 90% locking of plate interface faults. An earthquake in the shallow Semidi subduction zone could generate a tsunami that will inundate the US west coast more than the 1946 and 1964 earthquakes because the Semidi continental slope azimuth directs a tsunami southeastward.

  18. Chemical composition of red, brown and green macroalgae from Buarcos bay in Central West Coast of Portugal.

    PubMed

    Rodrigues, Dina; Freitas, Ana C; Pereira, Leonel; Rocha-Santos, Teresa A P; Vasconcelos, Marta W; Roriz, Mariana; Rodríguez-Alcalá, Luís M; Gomes, Ana M P; Duarte, Armando C

    2015-09-15

    Six representative edible seaweeds from the Central West Portuguese Coast, including the less studied Osmundea pinnatifida, were harvested from Buarcos bay, Portugal and their chemical characterization determined. Protein content, total sugar and fat contents ranged between 14.4% and 23.8%, 32.4% and 49.3% and 0.6-3.6%. Highest total phenolic content was observed in Codium tomentosum followed by Sargassum muticum and O. pinnatifida. Fatty acid (FA) composition covered the branched chain C13ai to C22:5 n3 with variable content in n6 and n3 FA; low n6:n3 ratios were observed in O. pinnatifida, Grateloupia turuturu and C. tomentosum. Some seaweed species may be seen as good sources of Ca, K, Mg and Fe, corroborating their good nutritional value. According to FTIR-ATR spectra, G. turuturu was associated with carrageenan seaweed producers whereas Gracilaria gracilis and O. pinnatifida were mostly agar producers. In the brown algae, S. muticum and Saccorhiza polyschides, alginates and fucoidans were the main polysaccharides found. PMID:25863629

  19. Community structure and seasonal variation of an inshore demersal fish community at Goa, West Coast of India

    NASA Astrophysics Data System (ADS)

    Ansari, Z. A.; Chatterji, A.; Ingole, B. S.; Sreepada, R. A.; Rivonkar, C. U.; Parulekar, A. H.

    1995-11-01

    Structure and seasonal variation of an inshore demersal fish assemblage have been described from 52 trawl samples collected between November 1988-November 1989 from Aguada and Marmugao Bays at Goa (west coast of India). A total of 12 519 individuals belonging to 59 species were collected. There was a clear seasonal fluctuation in relative abundance, biomass, species occurrence and species dominance. Families such as Sciaenidae, Leiognathidae, Cynoglossidae, Clupeidae and Ariidae dominated the demersal fish community, both in abundance and in biomass over the two areas. About 50% of the recorded species regularly occurred in the two areas. Density and biomass were high during post- and pre-monsoon seasons and low during the monsoon seasons. The species assemblages at the two sites were similar and showed much overlap of dominant species. Resident and quasi-resident species were dominant throughout the year and the overall population consisted mainly of marine coastal species. Cluster analysis showed species segregation into seasonal groups and intense association among different species groups. There was seasonal fluctuation in diversity indices and a marginal increase in species richness in Aguada bay was noticed. The dominance of juveniles in the catches indicate that the two areas serve as nursery grounds for the juveniles of several commercially important marine teleosts.

  20. Forensic investigation of aliphatic hydrocarbons in the sediments from selected mangrove ecosystems in the west coast of Peninsular Malaysia.

    PubMed

    Vaezzadeh, Vahab; Zakaria, Mohamad Pauzi; Shau-Hwai, Aileen Tan; Ibrahim, Zelina Zaiton; Mustafa, Shuhaimi; Abootalebi-Jahromi, Fatemeh; Masood, Najat; Magam, Sami Mohsen; Alkhadher, Sadeq Abdullah Abdo

    2015-11-15

    Peninsular Malaysia has gone through fast development during recent decades resulting in the release of large amounts of petroleum and its products into the environment. Aliphatic hydrocarbons are one of the major components of petroleum. Surface sediment samples were collected from five rivers along the west coast of Peninsular Malaysia and analyzed for aliphatic hydrocarbons. The total concentrations of C10 to C36 n-alkanes ranged from 27,945 to 254,463ng·g(-1)dry weight (dw). Evaluation of various n-alkane indices such as carbon preference index (CPI; 0.35 to 3.10) and average chain length (ACL; 26.74 to 29.23) of C25 to C33 n-alkanes indicated a predominance of petrogenic source n-alkanes in the lower parts of the Rivers, while biogenic origin n-alkanes from vascular plants are more predominant in the upper parts, especially in less polluted areas. Petrogenic sources of n-alkanes are predominantly heavy and degraded oil versus fresh oil inputs. PMID:26323864

  1. Biogeochemical cycling in the ocean. Part 1: Introduction to the effects of upwelling along the west coast of North America

    NASA Technical Reports Server (NTRS)

    Howe, John T.

    1986-01-01

    Coastal upwelling is examined as it relates to the cycling of chemical species in coastal waters along the west coast of North America. The temporal and spatial features of upwelling phenomena in the Eastern boundary regions of the North Pacific Ocean are presented and discussed in terms of upwelling episodes. Climate conditions affecting upwelling include: thermal effects, wind-induced shear stress which moves surface layers, and the curl of the wind stress vector which is thought to affect the extent and nature of upwelling and the formation of offshore convergent downwelling fronts. These effects and the interaction of sunlight and upwelled nutrients which result in a biological bloom in surface waters is modeled analytically. The roles of biological and chemical species, including the effects of predation, are discussed in that context, and relevant remote sensing and in situ observations are presented. Climatological, oceanographic, biological, physical, chemical events, and processes that pertain to biogeochemical cycling are presented and described by a set of partial differential equations. Simple preliminary results are obtained and are compared with data. Thus a fairly general framework has been laid where the many facets of biogeochemical cycling in coastal upwelled waters can be examined in their relationship to one another, and to the whole, to whatever level of detail or approximation is warranted or desired.

  2. Food web of the intertidal rocky shore of the west Portuguese coast - Determined by stable isotope analysis.

    PubMed

    Vinagre, Catarina; Mendonça, Vanessa; Narciso, Luís; Madeira, Carolina

    2015-09-01

    The characterization of food web structure, energy pathways and trophic linkages is essential for the understanding of ecosystem functioning. Isotopic analysis was performed on food web components of the rocky intertidal ecosystem in four sites along the Portuguese west coast. The aim was to 1) determine the general food web structure, 2) estimate the trophic level of the dominant organisms and 3) track the incorporation of organic carbon of different origins in the diet of the top consumers. In this food web, fish are top consumers, followed by shrimp. Anemones and gastropods are intermediate consumers, while bivalves and zooplankton are primary consumers. Macroalgae Bifurcaria bifurcata, Ulva lactuca, Fucus vesiculosus, Codium sp. and phytoplankton are the dominant producers. Two energy pathways were identified, pelagic and benthic. Reliance on the benthic energy pathway was high for many of the consumers but not as high as previously observed in subtidal coastal food webs. The maximum TL was 3.3, which is indicative of a relatively short food web. It is argued that the diet of top consumers relies directly on low levels of the food web to a considerable extent, instead of on intermediate levels, which shortens the trophic length of the food web. PMID:26275753

  3. Habitat characteristics promoting high density and condition of juvenile flatfish at nursery grounds on the west coast of Ireland

    NASA Astrophysics Data System (ADS)

    De Raedemaecker, F.; Brophy, D.; O'Connor, I.; Comerford, S.

    2012-10-01

    Coastal zones are essential nursery habitats for most juvenile flatfish species. Understanding the habitat requirements promoting high abundance and growth of juvenile flatfish is important for evaluating nursery habitat quality. The present study aimed to assess nursery ground quality for the most common flatfish species: dab (Limanda limanda) and plaice (Pleuronectes platessa), in Galway Bay, on the west coast of Ireland. Monthly surveys were carried out in the period after peak settlement over two years. Variability in flatfish density and Fulton's K condition was explained in relation to biotic and abiotic habitat characteristics, differing within and between distinct nursery grounds. Dab were concentrated in deeper waters, were negatively associated with shrimp densities and salinity and their abundance showed a decrease from June to September combined with interannual variation. Plaice densities were highly associated with shallower depths and high polychaete and shrimp densities and were negatively related with increased macroalgal cover and organic content. Most of the variability in Fulton's condition was explained by the same set of variables for both species; year and densities of crab and malacostracans. This analysis revealed important ecological mechanisms allowing the co-existence of two flatfish species in nursery grounds. However, high quality nursery grounds for dab and plaice differed and anthropogenic and climatic impacts on flatfish nurseries are likely to have a different impact on plaice and dab populations. Knowledge gained about the quality of nursery habitat for commercially important fish species provides a basis for mapping essential flatfish habitats to inform management plans for coastal areas.

  4. Monitoring of impact of anthropogenic inputs on water quality of mangrove ecosystem of Uran, Navi Mumbai, west coast of India.

    PubMed

    Pawar, Prabhakar R

    2013-10-15

    Surface water samples were collected from substations along Sheva creek and Dharamtar creek mangrove ecosystems of Uran (Raigad), Navi Mumbai, west coast of India. Water samples were collected fortnightly from April 2009 to March 2011 during spring low and high tides and were analyzed for pH, Temperature, Turbidity, Total solids (TS), Total dissolved solids (TDS), Total suspended solids (TSS), Dissolved oxygen (DO), Biochemical oxygen demand (BOD), Carbon dioxide (CO2), Chemical oxygen demand (COD), Salinity, Orthophosphate (O-PO4), Nitrite-nitrogen (NO2-N), Nitrate-nitrogen (NO3-N), and Silicates. Variables like pH, turbidity, TDS, salinity, DO, and BOD show seasonal variations. Higher content of O-PO4, NO3-N, and silicates is recorded due to discharge of domestic wastes and sewage, effluents from industries, oil tanking depots and also from maritime activities of Jawaharlal Nehru Port Trust (JNPT), hectic activities of Container Freight Stations (CFS), and other port wastes. This study reveals that water quality from mangrove ecosystems of Uran is deteriorating due to industrial pollution and that mangrove from Uran is facing the threat due to anthropogenic stress. PMID:23856298

  5. Forensic investigation of aliphatic hydrocarbons in the sediments from selected mangrove ecosystems in the west coast of Peninsular Malaysia.

    PubMed

    Vaezzadeh, Vahab; Zakaria, Mohamad Pauzi; Shau-Hwai, Aileen Tan; Ibrahim, Zelina Zaiton; Mustafa, Shuhaimi; Abootalebi-Jahromi, Fatemeh; Masood, Najat; Magam, Sami Mohsen; Alkhadher, Sadeq Abdullah Abdo

    2015-11-15

    Peninsular Malaysia has gone through fast development during recent decades resulting in the release of large amounts of petroleum and its products into the environment. Aliphatic hydrocarbons are one of the major components of petroleum. Surface sediment samples were collected from five rivers along the west coast of Peninsular Malaysia and analyzed for aliphatic hydrocarbons. The total concentrations of C10 to C36 n-alkanes ranged from 27,945 to 254,463ng·g(-1)dry weight (dw). Evaluation of various n-alkane indices such as carbon preference index (CPI; 0.35 to 3.10) and average chain length (ACL; 26.74 to 29.23) of C25 to C33 n-alkanes indicated a predominance of petrogenic source n-alkanes in the lower parts of the Rivers, while biogenic origin n-alkanes from vascular plants are more predominant in the upper parts, especially in less polluted areas. Petrogenic sources of n-alkanes are predominantly heavy and degraded oil versus fresh oil inputs.

  6. Tsunami vulnerability assessment mapping for the west coast of Peninsular Malaysia using a geographical information system (GIS)

    NASA Astrophysics Data System (ADS)

    Najihah, R.; Effendi, D. M.; Hairunnisa, M. A.; Masiri, K.

    2014-02-01

    The catastrophic Indian Ocean tsunami of 26 December 2004 raised a number of questions for scientist and politicians on how to deal with the tsunami risk and assessment in coastal regions. This paper discusses the challenges in tsunami vulnerability assessment and presents the result of tsunami disaster mapping and vulnerability assessment study for West Coast of Peninsular Malaysia. The spatial analysis was carried out using Geographical Information System (GIS) technology to demarcate spatially the tsunami affected village's boundary and suitable disaster management program can be quickly and easily developed. In combination with other thematic maps such as road maps, rail maps, school maps, and topographic map sheets it was possible to plan the accessibility and shelter to the affected people. The tsunami vulnerability map was used to identify the vulnerability of villages/village population to tsunami. In the tsunami vulnerability map, the intensity of the tsunami was classified as hazard zones based on the inundation level in meter (contour). The approach produced a tsunami vulnerability assessment map consists of considering scenarios of plausible extreme, tsunami-generating events, computing the tsunami inundation levels caused by different events and scenarios and estimating the possible range of casualties for computing inundation levels. The study provides an interactive means to identify the tsunami affected areas after the disaster and mapping the tsunami vulnerable village before for planning purpose were the essential exercises for managing future disasters.

  7. A possible transoceanic tsunami directed toward the U.S. west coast from the Semidi segment, Alaska convergent margin

    USGS Publications Warehouse

    von Huene, Roland; Miller, John J.; Dartnell, Peter

    2016-01-01

    The Semidi segment of the Alaska convergent margin appears capable of generating a giant tsunami like the one produced along the nearby Unimak segment in 1946. Reprocessed legacy seismic reflection data and a compilation of multibeam bathymetric surveys reveal structures that could generate such a tsunami. A 200 km long ridge or escarpment with crests >1 km high is the surface expression of an active out-of-sequence fault zone, recently referred to as a splay fault. Such faults are potentially tsunamigenic. This type of fault zone separates the relatively rigid rock of the margin framework from the anelastic accreted sediment prism. Seafloor relief of the ridge exceeds that of similar age accretionary prism ridges indicating preferential slip along the splay fault zone. The greater slip may derive from Quaternary subduction of the Patton Murray hot spot ridge that extends 200 km toward the east across the north Pacific. Estimates of tsunami repeat times from paleotsunami studies indicate that the Semidi segment could be near the end of its current inter-seismic cycle. GPS records from Chirikof Island at the shelf edge indicate 90% locking of plate interface faults. An earthquake in the shallow Semidi subduction zone could generate a tsunami that will inundate the US west coast more than the 1946 and 1964 earthquakes because the Semidi continental slope azimuth directs a tsunami southeastward.

  8. In situ gamma ray measurements of radionuclides at a disused phosphate mine on the West Coast of South Africa.

    PubMed

    Bezuidenhout, Jacques

    2015-12-01

    High levels of uranium and its radioactive progeny like radium is normally associated with phosphate mining. In Situ gamma ray spectroscopy as a survey tool has been successfully applied to assess radionuclide concentrations in various geographical environments. A transportable and robust gamma ray detection system (GISPI) was therefore employed to determine the concentrations of naturally occurring radionuclides at a disused phosphate mine on the West Coast of South Africa. The concentrations of radium, thorium and potassium were measured and plotted. The measurements showed fairly high concentrations with medians of 320 Bq/kg for (226)Ra, 64 Bq/kg for (232)Th and 390 Bq/kg for (40)K. The highest concentrations were however confined to specific areas of the mine. The effective dose due to gamma irradiation for the various areas of the mine was also estimated and the highest estimated level was 0.45 mSv/y. The article finally draws conclusions as to the origins and impact of the radiation. PMID:26254719

  9. Lacaziosis and lacaziosis-like prevalence among wild, common bottlenose dolphins Tursiops truncatus from the west coast of Florida, USA.

    PubMed

    Burdett Hart, Leslie; Rotstein, Dave S; Wells, Randall S; Bassos-Hull, Kim; Schwacke, Lori H

    2011-05-24

    Lacaziosis (lobomycosis; Lacazia loboi) is a fungal skin disease that naturally occurs only in humans and dolphins. The first reported case of lacaziosis in a bottlenose dolphin Tursiops truncatus occurred in 1970 in Sarasota Bay, Florida, USA, and subsequent photo-ID monitoring of the Sarasota Bay dolphin population has revealed persistence of the disease. The objectives of this study were to estimate lacaziosis prevalence (P) in 2 bottlenose dolphin populations on the west coast of Florida (Sarasota Bay and Charlotte Harbor) and compare disease occurrence to other published estimates of lacaziosis in dolphin populations across the globe. Historic photographic records of dolphins captured and released for health assessment purposes (Sarasota Bay) and photo-ID studies (Charlotte Harbor) were screened for evidence of lesions consistent with lacaziosis. Health assessment data revealed a prevalence of lacaziosis in the Sarasota Bay bottlenose dolphin population between 2 and 3%, and analyses of photo-ID data provided a lacaziosis-like prevalence estimate of 2% for Charlotte Harbor dolphins. With the exception of lacaziosis prevalence estimates for dolphins inhabiting the Indian River Lagoon (P = 0.068; P = 0.12), no statistically significant differences were seen among Sarasota Bay, Charlotte Harbor, and other published estimates. Although lacaziosis is a rare disease among these dolphin populations, studies that assess disease burden among different populations can assist with the surveillance of this zoonotic pathogen.

  10. Population structure of the black seabream Spondyliosoma cantharus along the south-west Portuguese coast inferred from otolith chemistry.

    PubMed

    Correia, A T; Gomes, P; Gonçalves, J M S; Erzini, K; Hamer, P A

    2012-02-01

    The chemistry of black seabream Spondyliosoma cantharus otoliths from three main fishery grounds (Olhão, Sagres and Sesimbra) located along c. 400 km of the Portuguese south and west coasts was examined. Element:Ca ratios were determined in whole otoliths and otolith cores of young adult specimens of 2-3 years of age. Using the data from whole otoliths, it was possible to discriminate among S. cantharus from the three fishing grounds with an average accuracy of 91%. Differences among fishing grounds were significant for all element:Ca ratios, and otoliths from Sagres had significantly higher levels of all ratios compared to the other fishing grounds. In contrast, the chemical composition of the otolith core, representative of the larval stage, showed limited variation among the fishing grounds, with an average discrimination accuracy of only 44%, although the Mg:Ca ratio of the otolith cores was also significantly higher for the Sagres samples. The data suggest that larval stages experienced a homogenous environment consistent with an offshore oceanic spawning. Juveniles appeared to display local residency on the inshore fishing grounds, areas probably characterized by greater environmental heterogeneity. Spondyliosoma cantharus population structure is consistent with distinct local population units that share a spawning ground providing recruits to different coastal fishery areas.

  11. In situ gamma ray measurements of radionuclides at a disused phosphate mine on the West Coast of South Africa.

    PubMed

    Bezuidenhout, Jacques

    2015-12-01

    High levels of uranium and its radioactive progeny like radium is normally associated with phosphate mining. In Situ gamma ray spectroscopy as a survey tool has been successfully applied to assess radionuclide concentrations in various geographical environments. A transportable and robust gamma ray detection system (GISPI) was therefore employed to determine the concentrations of naturally occurring radionuclides at a disused phosphate mine on the West Coast of South Africa. The concentrations of radium, thorium and potassium were measured and plotted. The measurements showed fairly high concentrations with medians of 320 Bq/kg for (226)Ra, 64 Bq/kg for (232)Th and 390 Bq/kg for (40)K. The highest concentrations were however confined to specific areas of the mine. The effective dose due to gamma irradiation for the various areas of the mine was also estimated and the highest estimated level was 0.45 mSv/y. The article finally draws conclusions as to the origins and impact of the radiation.

  12. Four new species of Pyropia (Bangiales, Rhodophyta) from the west coast of North America: the Pyropialanceolata species complex updated.

    PubMed

    Lindstrom, Sandra C; Hughey, Jeffery R; Rosas, Luis E Aguilar

    2015-01-01

    Recent molecular studies indicate that the Pyropialanceolata species complex on the west coast of North America is more speciose than previously thought. Based on extensive rbcL gene sequencing of representative specimens we recognize seven species in the complex, three of which are newly described: Pyropiamontereyensis sp. nov., Pyropiacolumbiensis sp. nov., and Pyropiaprotolanceolata sp. nov. The new species are all lanceolate, at least when young, and occur in the upper mid to high intertidal zone primarily in winter and early spring. Pyropiamontereyensis and Pyropiacolumbiensis are sister taxa that are distributed south and north of Cape Mendocino, respectively, and both occur slightly lower on the shore than Pyropialanceolata or Pyropiapseudolanceolata. Pyropiaprotolanceolata is known thus far only from Morro Rock and the Monterey Peninsula, California; it occurs basally to the other species in the complex in the molecular phylogeny. A fourth newly described species, Pyropiabajacaliforniensis sp. nov., is more closely related to Pyropianereocystis than to species in this complex proper. It is a thin species with undulate margins known only from Moss Landing, Monterey Bay, California, and northern Baja California; it also occurs in the high intertidal in spring. Porphyramumfordii, a high intertidal winter species that has frequently been confused with species in the Pyropialanceolata complex, has now been confirmed to occur from Calvert Island, British Columbia, to Pescadero State Park, California.

  13. Atmospheric pollutants and their influence on acidification of rain water at an industrial location on the West Coast OF India

    NASA Astrophysics Data System (ADS)

    Khemani, L. T.; Momin, G. A.; Rao, P. S. P.; Pillai, A. G.; Safai, P. D.; Mohan, K.; Rao, M. G.

    The chemical analysis of rain water samples at 11 locations along with measurements of atmospheric aerosols and their size distributions were made to study the influence of pollutants on acidification of rain water during the monsoon season of 1990 at Chembur-Trombay area, a highly industrialized belt in Bombay region located on the west coast of India. The concentrations of acid precursor gases, namely, SO 2 and NO, emanating from industries were low and their influence on acidification was limited to a few kilometer radius of their sources. Whereas, the deposition of ionic components (Na +, K +, Ca 2+, Mg 2+ and CI -) whose sources are natural (sea and soil) were uniformly distributed throughout the region as compared to those released from man-made sources. The high concentration of alkaline components, especially Ca 2+ from natural sources and NH 3 released from a fertilizer plant, were responsible for neutralising H + ion concentration generated from the acidic components (SO 42- and N0 3-). The variation from acidic (1970s) to alkaline (1990s) nature of rainwater in the area maybe due to the change in the use of fuel from coal to natural gas, which contains less sulphur and also, the pollution control measures taken by the industries.

  14. Health of Chinese illegal immigrants who arrived by boat on the West Coast of Canada in 1999.

    PubMed

    Allan, G Michael; Szafran, Olga

    2005-10-01

    This was a retrospective review and descriptive analysis of the findings from the medical screening examinations conducted on the illegal migrants from Fujian Province of China (n = 589) who arrived on four boats on the West Coast of Canada between June 14 and September 9, 1999. The Canadian Navy conducted a screening medical exam of the illegal migrants, with Health Canada and Citizenship and Immigration Canada providing suggestions on the format of the exam. The illegal Chinese migrants were predominantly young, male adults. The most prevalent medical conditions detected were dermatological (55.2%), dental problems (25%), trauma (9.2%), urogenital (7.6%), and head/neck (6.6%). Recently induced trauma was more prevalent among females (20.5%) than males (6.5%). One case of community-acquired pneumonia was identified and later diagnosed as active pulmonary tuberculosis. Physicians dealing with illegal migrants should look for unusual physical findings and have a higher clinical suspicion regarding infectious diseases (tuberculosis, scabies) and abuse. Future encounters with illegal migrants should include standardized immigration screening exams, with adequate history taking and follow-up.

  15. Long-time trends in ship traffic noise for four sites off the North American West Coast.

    PubMed

    Andrew, Rex K; Howe, Bruce M; Mercer, James A

    2011-02-01

    Measurements (1994-2007) from four cabled-to-shore hydrophone systems located off the North American west coast permit extensive comparisons between "contemporary" low frequency ship traffic noise (25-50 Hz) collected in the past decade to measurements made over 1963-1965 with the same in-water equipment at the same sites. An increase of roughly 10 dB over the band 25-40 Hz at one site has already been reported [Andrew et al., Acoust. Res. Lett. Online 3(2), 65-70 (2002)]. Newly corrected data from the remaining three systems generally corroborate this increase. Simple linear trend lines of the contemporary traffic noise (duration 6 to 12+ years) show that recent levels are slightly increasing, holding steady, or decreasing. These results confirm the prediction by Ross that the rate of increase in traffic noise would be far less at the end of the 20th century compared to that observed in the 1950s and 1960s.

  16. Four new species of Pyropia (Bangiales, Rhodophyta) from the west coast of North America: the Pyropia lanceolata species complex updated

    PubMed Central

    Lindstrom, Sandra C.; Hughey, Jeffery R.; Rosas, Luis E. Aguilar

    2015-01-01

    Abstract Recent molecular studies indicate that the Pyropia lanceolata species complex on the west coast of North America is more speciose than previously thought. Based on extensive rbcL gene sequencing of representative specimens we recognize seven species in the complex, three of which are newly described: Pyropia montereyensis sp. nov., Pyropia columbiensis sp. nov., and Pyropia protolanceolata sp. nov. The new species are all lanceolate, at least when young, and occur in the upper mid to high intertidal zone primarily in winter and early spring. Pyropia montereyensis and Pyropia columbiensis are sister taxa that are distributed south and north of Cape Mendocino, respectively, and both occur slightly lower on the shore than Pyropia lanceolata or Pyropia pseudolanceolata. Pyropia protolanceolata is known thus far only from Morro Rock and the Monterey Peninsula, California; it occurs basally to the other species in the complex in the molecular phylogeny. A fourth newly described species, Pyropia bajacaliforniensis sp. nov., is more closely related to Pyropia nereocystis than to species in this complex proper. It is a thin species with undulate margins known only from Moss Landing, Monterey Bay, California, and northern Baja California; it also occurs in the high intertidal in spring. Porphyra mumfordii, a high intertidal winter species that has frequently been confused with species in the Pyropia lanceolata complex, has now been confirmed to occur from Calvert Island, British Columbia, to Pescadero State Park, California. PMID:26312033

  17. Sewage treatment plant associated genetic differentiation in the blue mussel from the Baltic Sea and Swedish west coast

    PubMed Central

    Lönn, Mikael; Lind, Emma E.; Świeżak, Justyna; Smolarz, Katarzyna; Grahn, Mats

    2016-01-01

    Human-derived environmental pollutants and nutrients that reach the aquatic environment through sewage effluents, agricultural and industrial processes are constantly contributing to environmental changes that serve as drivers for adaptive responses and evolutionary changes in many taxa. In this study, we examined how two types of point sources of aquatic environmental pollution, harbors and sewage treatment plants, affect gene diversity and genetic differentiation in the blue mussel in the Baltic Sea area and off the Swedish west coast (Skagerrak). Reference sites (REF) were geographically paired with sites from sewage treatments plant (STP) and harbors (HAR) with a nested sampling scheme, and genetic differentiation was evaluated using a high-resolution marker amplified fragment length polymorphism (AFLP). This study showed that genetic composition in the Baltic Sea blue mussel was associated with exposure to sewage treatment plant effluents. In addition, mussel populations from harbors were genetically divergent, in contrast to the sewage treatment plant populations, suggesting that there is an effect of pollution from harbors but that the direction is divergent and site specific, while the pollution effect from sewage treatment plants on the genetic composition of blue mussel populations acts in the same direction in the investigated sites. PMID:27812424

  18. Haemonchotolerance in West African Dwarf goats: contribution to sustainable, anthelmintics-free helminth control in traditionally managed Nigerian dwarf goats

    PubMed Central

    Chiejina, Samuel N.; Behnke, Jerzy M.; Fakae, Barineme B.

    2015-01-01

    West African Dwarf (WAD) goats are extremely important in the rural village economy of West Africa, but still little is known about their biology, ecology and capacity to cope with gastrointestinal nematode (GIN) infections. Here, we summarise the history of this breed and explain its economic importance in rural West Africa. We review recent work showing that Nigerian WAD goats are highly trypanotolerant and resist infections with Haemonchus contortus more effectively than other breeds of domestic goat (haemonchotolerance). We believe that haemonchotolerance is largely responsible for the generally low level GIN infections and absence of clinical haemonchosis in WADs under field conditions, and has contributed to the relatively successful and sustainable, anthelmintics-free, small-scale system of goat husbandry in Nigeria’s humid zone, and is immunologically based and genetically controlled. If haemonchotolerance can be shown to be genetically controlled, it should be possible to exploit the underlying genes to improve GIN resistance among productive fibre and milk producing breeds of goats, most of which are highly susceptible to nematode infections. Genetic resistance to GIN and trypanosome infections would obviate the need for expensive chemotherapy, mostly unaffordable to small-holder farmers in Africa, and a significant cost of goat husbandry in more developed countries. Either introgression of resistance alleles into susceptible breeds by conventional breeding, or transgenesis could be used to develop novel parasite-resistant, but highly productive breeds, or to improve the resistance of existing breeds, benefitting the local West African rural economy as well as global caprine livestock agriculture. PMID:25744655

  19. Stratospheric variability of wave activity and parameters in equatorial coastal and tropical sites during the West African monsoon

    NASA Astrophysics Data System (ADS)

    Kafando, P.; Chane-Ming, F.; Petitdidier, M.

    2015-08-01

    Recent numerical studies in stratospheric dynamics and its variability as well as climate, have highlighted the need of more observational analyses to improve simulation of the West African monsoon (WAM). In this paper, activity and spectral characteristics of short-scale vertical waves (wavelengths <4 km) are analysed in equatorial coastal and tropical lower stratosphere during the WAM. A first detailed description of such waves over West Africa is derived from high-resolution vertical profiles of temperature and horizontal wind obtained during Intensive Observation Period of the African Monsoon Multidisciplinary Analyses (AMMA) Campaign 2006. Monthly variation of wave energy density is revealed to trace the progression of the inter-tropical convergence zone (ITCZ) over West Africa. Mesoscale inertia gravity-waves structures with vertical and horizontal wavelengths of 1.5-2.5 and 400-1100 km respectively and intrinsic frequencies of 1.1-2.2 f or periods <2 days are observed in the tropical LS with intense activity during July and August when the WAM is installed over the tropical West Africa. Over equatorial region, gravity waves with intrinsic frequencies of 1.4-4 f or periods <5.2 days, vertical wavelength of 2.1 km and long horizontal wavelengths of 1300 km are intense during the WAM coastal phase. From July to October, gravity waves with intrinsic frequencies of 1.2-3.8 f or periods <6 days, vertical wavelength of 2.1 km and horizontal wavelengths of 1650 km are less intense during the WAM Sahelian phase of the WAM, March-June. Unlike potential energy density, kinetic energy density is observed to be a good proxy for the activity of short-scale vertical waves during the WAM because quasi-inertial waves are dominant. Long-term wave activity variation from January 2001 to December 2009, highlights strong year-to-year variation superimposed on convective activity and quasi-biennial oscillation-like variations especially above tropical stations.

  20. Identification, tissue distribution and functional characterization of the ghrelin receptor in West African lungfish, Protopterus annectens.

    PubMed

    Kaiya, Hiroyuki; Konno, Norifumi; Kangawa, Kenji; Uchiyama, Minoru; Miyazato, Mikiya

    2014-12-01

    We identified two ghrelin receptor isoforms, the ghrelin receptor type-1a (GHS-R1a) and its alternative splice form (GHS-R1b) for West African lungfish, Protopterus annectens. Lungfish GHS-R1a and 1b comprised 361 and 281 amino acids, respectively. Lungfish GHS-R1a showed the highest identity to coelacanth GHS-R1a (80.4%). The highest expression of GHS-R1a mRNAs was seen in the brain, liver, ovary, heart, intestine, and gills. GHS-R1b mRNAs were also detected in the same tissues with GHS-R1a, but their expression level was 1/20 that of GHS-R1a. In human embryonic kidney 293 cells transiently expressing lungfish GHS-R1a, rat and bullfrog ghrelin, and two GHS-R1a agonists, GHRP-6 and hexarelin, increased intracellular Ca(2+) concentrations. The intensity of the Ca(2+) increases induced by GHS-R1a agonists was twice when compared to that induced by ghrelin, although the median effective doses (ED50) were similar, suggesting a long-lasting effect of GHS-R1a agonists with similar affinity. We also examined changes in the GHS-R gene expression during an eight-week estivation. Body weight was slightly lowered, but plasma sodium and glucose concentrations decreased; plasma urea concentration increased significantly 4weeks after the start of estivation. Overall, expression of GHS-R1a mRNA decreased, but changes in GHS-R1b mRNA expression were inconsistent with those of GHS-R1a during estivation, suggesting an involvement of GHS-R in energy homeostasis, as seen in mammals. Our results suggest that the ghrelin-GHS-R1a system is present in this lungfish although ghrelin has not yet been found. The structure of GHS-R1a is closer to that of tetrapods than Actinopterygian fish, indicating a process of evolution that follows the Crossopterygii such as coelacanth.

  1. Geohydrology, Geochemistry, and Ground-Water Simulation-Optimization of the Central and West Coast Basins, Los Angeles County, California

    USGS Publications Warehouse

    Reichard, Eric G.; Land, Michael; Crawford, Steven M.; Johnson, Tyler D.; Everett, Rhett; Kulshan, Trayle V.; Ponti, Daniel J.; Halford, Keith L.; Johnson, Theodore A.; Paybins, Katherine S.; Nishikawa, Tracy

    2003-01-01

    Historical ground-water development of the Central and West Coast Basins in Los Angeles County, California through the first half of the 20th century caused large water-level declines and induced seawater intrusion. Because of this, the basins were adjudicated and numerous ground-water management activities were implemented, including increased water spreading, construction of injection barriers, increased delivery of imported water, and increased use of reclaimed water. In order to improve the scientific basis for these water management activities, an extensive data collection program was undertaken, geohydrological and geochemical analyses were conducted, and ground-water flow simulation and optimization models were developed. In this project, extensive hydraulic, geologic, and chemical data were collected from new multiple-well monitoring sites. On the basis of these data and data compiled and collected from existing wells, the regional geohydrologic framework was characterized. For the purposes of modeling, the three-dimensional aquifer system was divided into four aquifer systems?the Recent, Lakewood, Upper San Pedro, and Lower San Pedro aquifer systems. Most pumpage in the two basins is from the Upper San Pedro aquifer system. Assessment of the three-dimensional geochemical data provides insight into the sources of recharge and the movement and age of ground water in the study area. Major-ion data indicate the chemical character of water containing less than 500 mg/L dissolved solids generally grades from calcium-bicarbonate/sulfate to sodium bicarbonate. Sodium-chloride water, high in dissolved solids, is present in wells near the coast. Stable isotopes of oxygen and hydrogen provide information on sources of recharge to the basin, including imported water and water originating in the San Fernando Valley, San Gabriel Valley, and the coastal plain and surrounding hills. Tritium and carbon-14 data provide information on relative ground-water ages. Water with

  2. Small reservoirs in the West African savanna: Usage, monitoring and impact (Invited)

    NASA Astrophysics Data System (ADS)

    Van De Giesen, N.; Liebe, J. R.; Annor, F.; Andreini, M.

    2013-12-01

    The West African savanna is dotted with thousands of small reservoirs. These reservoirs were primarily built for irrigation purposes, supplying supplementary irrigation in the rainy season and full irrigation in the dry season. Some reservoirs were specifically constructed for watering cattle. Most reservoirs, however, now fulfill a multitude of functions in addition to irrigation and cattle watering, such as fishing, bathing, household water, supply of construction materials, and recreation. In the framework of the Small Reservoirs Project (www.smallreservoirs.org), extensive research has been undertaken over the past ten years that addresses the functioning of these reservoirs and the development of new monitoring methods. This presentation will give a general overview of our findings with respect to history, usage, and hydrological impact of small reservoirs in West Africa. In general, no comprehensive databases are available to local and national governments that contain all reservoirs and their attributes. Remote sensing, therefore, offers an interesting alternative to produce inventories of small reservoirs in a cost effective way. The most straightforward application is the mapping of small reservoirs with the aid of optical satellite images. Open water tends to stand out clearly from its surroundings in such images, allowing for relatively accurate determination of the location and surface area of the reservoirs. An important early discovery was that within a given geomorphological region, there is a very good correlation between surface area and storage volume. Once this correlation is established through a small sub-sample of the reservoirs, all volumes can be calculated on the basis of surfaces as determined through remote sensing. In turn, this opens up the opportunity to monitor water storage over the year by means of satellite images. Optical images are usually not available during large parts of the year due to cloud cover. This holds especially true

  3. Sclerochronology of Holocene oyster shells (Crassostrea gigas) from the West Coast of Bohai Sea, China

    NASA Astrophysics Data System (ADS)

    Fan, C.; Koeniger, P.; Wang, H.; Frechen, M.

    2009-04-01

    Sclerochronology, the study of periodic increments in skeletal organisms, can decipher the life history and environmental records preserved in fossil shells. Although there have been a number of studies that apply isotopic analyses to shells in open ocean and fresh water, investigations for brackish environments are rare. One of the common inhabitants in estuaries is the Crassostrea oyster. Kirby et al. (1998) demonstrated a close correspondence between the ligamental increments of convex and concave bands and yearly ^18O cycles; Andrus and Crowe (2000) found a close correspondence between translucent growth bands on the cross-section of the hinge and yearly ^18O cycles. They conclude that the morphological features on hinge and growth bands on the cross-section are formed annually and can be used to determine accurately age and growth rate in this species. However, Surge et al. (2001) could not find that these morphologic features have seasonal significance in the C. virginica shells. Therefore, these concave ridges are not reliable independent proxies of seasonality. These studies were carried out with C. virginica shells; none was studied with nature C. gigas, which was widely distributed along the Pacific coastal area. C. gigas has been introduced from its native home to all over the world, ranging from North America to Australia and Europe; it has become an important commercial harvest in many of these places. Buried Holocene oyster shells of C. gigas were sampled from a huge buried oyster reef on the West of Bohai Sea, China. One of these shells was selected for high resolution micro-sampling and stable isotope analyses testing the assumption that C. gigas ligamental increments are annual in nature. We analyzed 236 consecutive samples from the shell to show that morphologic features both on hinge and cross-section are annual by comparing them to the ^18O profiles. We tested the assumption that the morphologic features of C.gigas are delineated by convex tops

  4. Standardising Visual Control Devices for Tsetse Flies: Central and West African Species Glossina palpalis palpalis

    PubMed Central

    Kaba, Dramane; Zacarie, Tusevo; M'Pondi, Alexis Makumyaviri; Njiokou, Flobert; Bosson-Vanga, Henriette; Kröber, Thomas; McMullin, Andrew; Mihok, Steve; Guerin, Patrick M.

    2014-01-01

    Background Glossina palpalis palpalis (G. p. palpalis) is one of the principal vectors of sleeping sickness and nagana in Africa with a geographical range stretching from Liberia in West Africa to Angola in Central Africa. It inhabits tropical rain forest but has also adapted to urban settlements. We set out to standardize a long-lasting, practical and cost-effective visually attractive device that would induce the strongest landing response by G. p. palpalis for future use as an insecticide-impregnated tool in area-wide population suppression of this fly across its range. Methodology/Principal Findings Trials were conducted in wet and dry seasons in the Ivory Coast, Cameroon, the Democratic Republic of Congo and Angola to measure the performance of traps (biconical, monoconical and pyramidal) and targets of different sizes and colours, with and without chemical baits, at different population densities and under different environmental conditions. Adhesive film was used as a practical enumerator at these remote locations to compare landing efficiencies of devices. Independent of season and country, both phthalogen blue-black and blue-black-blue 1 m2 targets covered with adhesive film proved to be as good as traps in phthalogen blue or turquoise blue for capturing G. p. palpalis. Trap efficiency varied (8–51%). There was no difference between the performance of blue-black and blue-black-blue 1 m2 targets. Baiting with chemicals augmented the overall performance of targets relative to traps. Landings on smaller phthalogen blue-black 0.25 m2 square targets were not significantly different from either 1 m2 blue-black-blue or blue-black square targets. Three times more flies were captured per unit area on the smaller device. Conclusions/Significance Blue-black 0.25 m2 cloth targets show promise as simple cost effective devices for management of G. p. palpalis as they can be used for both control when impregnated with insecticide and for population sampling when

  5. Geochronology of the Birim Supergroup of the West African craton in the Wa-Bolé region of west-central Ghana: Implications for the stratigraphic framework

    NASA Astrophysics Data System (ADS)

    de Kock, G. S.; Armstrong, R. A.; Siegfried, H. P.; Thomas, E.

    2011-01-01

    The Birim rocks of the West African craton comprise belts of greenschist- to amphibolite-grade gneiss and schist, and subparallel basins of greenschist-grade phyllite of volcaniclastic and epiclastic origin, which were intruded by igneous rocks. The granitoids intruded between 2213 and 2060 Ma and overlap with the volcaniclastic units dated between 2211 and 2064 Ma. The simultaneous occurrence of the magmatic events and irregular distribution of the rock ages hamper the formulation of a stratigraphic succession. SHRIMP spot analyses were done on older cores, crystals and rims from 23 rocks from the Bolé-Wa region in west-central Ghana. The crystallization ages range from 2195 to 2118 Ma, the inherited ages from 2876 to 2130 Ma, and metamorphic ages from 2114 to 2090 Ma. Aided by metamorphic, structural and chemical studies an older geotectonic cycle (2195-2150 Ma), containing the Dole and Guropie Suite and Bolé Group, was established. These units were subjected to several orthogonal and shear deformation events. These events were followed by the contemporaneous Sawla calc-alkaline monzonitic plutonism (2132-2126 Ma) and deposition of the epiclastic Maluwe Group (2137-2125 Ma) of calc-alkaline felsic to tholeiitic volcanic origin. Deformation of the basin beds was succeeded by the intrusion of the Tanina Suite granitoids of 2122-2120 Ma, which, themselves, were deformed prior to 2119 Ma. At 2118 Ma syenite and gabbro intruded along conjugate extension fractures. The gabbro and syenite of the Wakawaka Suite were only affected by three events of brittle strike-slip faulting. The first had significant displacement along NNE- to NE-directed shear zones, while the latter only formed conjugate joint systems with limited transport. Palaeo- to Neoarchaean cores, the oldest yet reported in the Baoulé Mossi domain, are restricted to the gneissic Dole Suite biotite granites. The presence of Dole-, Guropie-, Sawla-, and Tanina-aged older cores and grains in younger rocks

  6. Importance of mitochondrial haplotypes and maternal lineage in sprint performance among individuals of West African ancestry.

    PubMed

    Deason, M; Scott, R; Irwin, L; Macaulay, V; Fuku, N; Tanaka, M; Irving, R; Charlton, V; Morrison, E; Austin, K; Pitsiladis, Y P

    2012-04-01

    Mitochondrial DNA (mtDNA) is inherited solely along the matriline, giving insight into both ancestry and prehistory. Individuals of sub-Saharan ancestry are overrepresented in sprint athletics, suggesting a genetic advantage. The purpose of this study was to compare the mtDNA haplogroup data of elite groups of Jamaican and African-American sprinters against respective controls to assess any differences in maternal lineage. The first hypervariable region of mtDNA was haplogrouped in elite Jamaican athletes (N=107) and Jamaican controls (N=293), and elite African-American athletes (N=119) and African-American controls (N=1148). Exact tests of total population differentiation were performed on total haplogroup frequencies. The frequency of non-sub-Saharan haplogroups in Jamaican athletes and Jamaican controls was similar (1.87% and 1.71%, respectively) and lower than that of African-American athletes and African-American controls (21.01% and 8.19%, respectively). There was no significant difference in total haplogroup frequencies between Jamaican athletes and Jamaican controls (P=0.551 ± 0.005); however, there was a highly significant difference between African-American athletes and African-American controls (P<0.001). The finding of statistically similar mtDNA haplogroup distributions in Jamaican athletes and Jamaican controls suggests that elite Jamaican sprinters are derived from the same source population and there is neither population stratification nor isolation for sprint performance. The significant difference between African-American sprinters and African-American controls suggests that the maternal admixture may play a role in sprint performance.

  7. Impact of GCM boundary forcing on regional climate modeling of West African summer monsoon precipitation and circulation features

    NASA Astrophysics Data System (ADS)

    Kebe, Ibourahima; Sylla, Mouhamadou Bamba; Omotosho, Jerome Adebayo; Nikiema, Pinghouinde Michel; Gibba, Peter; Giorgi, Filippo

    2016-05-01

    In this study, the latest version of the International Centre for Theoretical Physics Regional Climate Model (RegCM4) driven by three CMIP5 Global Climate Models (GCMs) is used at 25 km grid spacing over West Africa to investigate the impact of lateral boundary forcings on the simulation of monsoon precipitation and its relationship with regional circulation features. We find that the RegCM4 experiments along with their multimodel ensemble generally reproduce the location of the main precipitation characteristics over the region and improve upon the corresponding driving GCMs. However, the provision of different forcing boundary conditions leads to substantially different precipitation magnitudes and spatial patterns. For instance, while RegCM4 nested within GFDL-ESM-2M and HadGEM2-ES exhibits some underestimations of precipitation and an excessively narrow Intertropical Convergence Zone, the MPI-ESM-MR driven run produces precipitation spatial distribution and magnitudes more similar to observations. Such a superior performance originates from a much better simulation of the interactions between baroclinicity, temperature gradient and African Easterly Jet along with an improved connection between the Isentropic Potential Vorticity, its gradient and the African Easterly Waves dynamics. We conclude that a good performing GCM in terms of monsoon dynamical features (in this case MPI-ESM-MR) is needed to drive RCMs in order to achieve a better representation of the West Africa summer monsoon precipitation.

  8. Comparative study of potential transfer of natural and anthropogenic cadmium to plankton communities in the North-West African upwelling.

    PubMed

    Auger, P A; Machu, E; Gorgues, T; Grima, N; Waeles, M

    2015-02-01

    A Lagrangian approach based on a physical-biogeochemical modeling was used to compare the potential transfer of cadmium (Cd) from natural and anthropogenic sources to plankton communities (Cd-uptake) in the North-West African upwelling. In this region, coastal upwelling was estimated to be the main natural source of Cd while the most significant anthropogenic source for marine ecosystem is provided by phosphate industry. In our model experiment, Cd-uptake (natural or anthropogenic) in the North-West African upwelling is the result of an interplay between the Cd dispersion (by advection processes) and the simulated biological productivity. In the Moroccan waters, advection processes limit the residence time of water masses resulting in a low natural Cd-uptake by plankton communities while anthropogenic Cd-uptake is high. As expected, the situation is reversed in the Senegalo-Mauritanian upwelling where natural Cd-uptake is higher than anthropogenic Cd-uptake. Based upon an estimate of Cd sources, our modeling study shows, unexpectedly, that the anthropogenic signal of potential Cd-bioaccumulation in the Moroccan upwelling is of the same order of magnitude as the natural signal mainly present in the Senegalo-Mauritanian upwelling region. A comparison with observed Cd levels in mollusk and fishes, which shows overall agreement with our simulations, is confirming our estimates.

  9. HLA-DRB1 and -DQB1 loci in three west African ethnic groups: genetic relationship with sub-Saharan African and European populations.

    PubMed

    Lulli, Patrizia; Mangano, Valentina D; Onori, Annamaria; Batini, Chiara; Luoni, Gaia; Sirima, Bienvenu S; Nebie, Issa; Chessa, Luciana; Petrarca, Vincenzo; Modiano, David

    2009-11-01

    The Fulani of west Africa have been shown to be less susceptible to malaria and to mount a stronger immune response to malaria than sympatric ethnic groups. The analysis of HLA diversity is useful for the assessment of the genetic distance between the Fulani and sympatric populations, which represents the necessary theoretical background for the investigation of genetic determinants of susceptibility to malaria. We assessed the polymorphism of HLA-DRB1 and -DQB1 loci and analyzed the distribution of alleles/haplotypes in Fulani, Mossi, and Rimaibé from Burkina Faso. We then investigated the genetic relationship of these three ethnic groups with other sub-Saharan African populations as well as with Europeans. We confirmed that the Fulani from Burkina Faso are genetically distinct from sympatric Mossi and Rimaibé. Furthermore the Fulani from Burkina Faso are close to those from The Gambia and, intriguingly, share the distribution of specific alleles with east African populations (Amhara and Oromo). It is noteworthy that the HLA-DRB1*04 and -DQB1*02 alleles, which are implicated in the development of several autoimmune diseases, are present at high frequency in the Fulani, suggesting their potential involvement in the enhanced immune reactivity observed in this population.

  10. TI: The West Coast and Alaska Tsunami Warning Center Forecast Model Project Applied to an Operational Tsunami Threat-database

    NASA Astrophysics Data System (ADS)

    Knight, W.; Huang, P.; Whitmore, P.; Sterling, K.

    2008-12-01

    Continuous improvement in the NOAA/West Coast & Alaska Tsunami Warning Center (WCATWC) forecast model has allowed the consideration of new uses for this model. These improvements include a finer propagation mesh, more model sources and magnitudes, runup boundary conditions, and continuous, unbroken fine coastal meshes. The focus of this report is on a new operational use of the model at the WCATWC - creation of a threat database of tsunami impacts on US and Canadian coastlines. Since all forecast model data is pre-computed, this concept should be easily realized. One recent case which showed the utility of a model-based threat database was the 4-1-2007 Solomon Islands Tsunami event. Tsunami energy maps clearly showed the energy was directed southwest and was no danger to regions to the northeast. Another case was the use of modeled tsunamis and their synthetic mareograms in the design of Gulf and Atlantic coast tsunami warning criteria. Currently, the only quantitative model data to appear in tsunami messages are ETAs for the leading edge of the tsunami wave train (the expected impact level is described in text - based on forecast model data). Since runups can now be forecasted for any coastal point, they can be used to constrain initial warning/watch/advisory messages to only threatened regions and can be saved to a database for later inclusion (along with ETAs) in tsunami bulletins. Present practice is to include all areas within a certain travel time or distance from epicenter in the initial warning bulletin, regardless of the threat. Since watch-warning- advisory breakpoints are based in the later bulletins on forecasted wave heights, the database can also be used to refine the extent of the warned zones. With full modeled mareograms similarly saved to a database, additional wave information like initial recession / elevation, or ETAs for first and highest waves can be added to tsunami bulletins. By comparison of scaled model prediction to historic tide gauge

  11. African ancestry is associated with risk of asthma and high total serum IgE in a population from the Caribbean Coast of Colombia.

    PubMed

    Vergara, Candelaria; Caraballo, Luis; Mercado, Dilia; Jimenez, Silvia; Rojas, Winston; Rafaels, Nicholas; Hand, Tracey; Campbell, Monica; Tsai, Yuhjung J; Gao, Li; Duque, Constanza; Lopez, Sergio; Bedoya, Gabriel; Ruiz-Linares, Andrés; Barnes, Kathleen C

    2009-06-01

    African descended populations exhibit an increased prevalence of asthma and allergies compared to Europeans. One approach to distinguish between environmental and genetic explanations for this difference is to study relationships of asthma risk to individual admixture. We aimed to determine the admixture proportions of a case-control sample from the Caribbean Coast of Colombia currently participating in genetic studies for asthma, and to test for population stratification and association between African ancestry and asthma and total serum IgE levels (tIgE). We genotyped 368 asthmatics and 365 non-asthmatics for 52 autosomal ancestry informative markers, six mtDNA haplogroups and nine haplogroups and five microsatellites in Y chromosome. Autosomal admixture proportions, population stratification, and associations between ancestry and the phenotypes were estimated by ADMIXMAP. The average admixture proportions among asthmatics were 42.8% European, 39.9% African and 17.2% Native American and among non-asthmatics they were 44.2% (P = 0.068), 37.6% (P = 0.007) and 18.1% (P = 0.050), respectively. In the total sample, the paternal contributions were 71% European, 25% African and 4.0% Native American and the maternal lineages were 56.8% Native American, and 20.2% African; 22.9% of the individuals carried other non-Native American mtDNA haplogroups. African ancestry was significantly associated with asthma (OR: 2.97; 95% CI: 1.08-8.08), high tIgE (OR: 1.9; 95% CI: 1.17-3.12) and socioeconomic status (OR = 0.64; 95% CI: 0.47-0.87). Significant population stratification was observed in this sample. Our findings indicate that genetic factors can explain the association between asthma and African ancestry and suggest that this sample is a useful resource for performing admixture mapping for asthma.

  12. Quantification of Coastal Macro Algae Iodine Emissions and its Spatial Variability at the West Coast of Ireland

    NASA Astrophysics Data System (ADS)

    Pöhler, Denis; Horbanski, Martin; Schmitt, Stefan; Platt, Ulrich

    2014-05-01

    Reactive iodine species are emitted by macro algae in the intertidal zone of coastal sites during low tide. Due to the oxidation to iodine oxide (IO) and thus reduction of ozone, they may have a significant influence on the local atmosphere. Further high iodine oxide levels may act as precursors for particle formation and therefore have a potential impact on climate. A correlation between iodine oxide and particle formation could be observed in previous field studies. However, previous measurements of iodine and iodine oxide have been performed only at very few sites, mainly at the atmospheric research station Mace Head located at the west coast of Ireland. An observation of the dominant sources, the spatial distribution and the impact on larger scales was not possible so far. To investigate these questions we performed intensive measurements at eight different sites along the west coast of Ireland in 2011 and 2012. Therefore, we applied a mobile Long Path (LP)-DOAS for path averaged IO measurements and a mobile Cavity Enhanced (CE)- DOAS instrument for in-situ IO measurements at different locations. Additionally, a static Long Path-DOAS system for IO, OIO and I2 measurements located at Mace Head was applied. This allows comparing directly different locations with the reference station Mace Head without the influence of locally varying meteorology and comparing results also to former observations. We could confirm previous results that the macro algae species Laminaria digitata is the strongest iodine emitting algae. However, we observed significant differences to former investigations and conclusions. First, iodine oxide concentrations were much higher (typically factor of 10 and more) on every measuring site compared to Mace Head. IO reaching levels up to 40ppt observed with the LP-DOAS and 70ppt @ 1.2m height with the CE-DOAS. Second, we found out that Laminaria digitata is not a dominant iodine source to the atmosphere, while Ascophyllum nodosum due to its high

  13. Distributions and bioconcentration characteristics of perfluorinated compounds in environmental samples collected from the west coast of Korea.

    PubMed

    Naile, Jonathan E; Khim, Jong Seong; Hong, Seongjin; Park, Jinsoon; Kwon, Bong-Oh; Ryu, Jong Seong; Hwang, Jin Hwan; Jones, Paul D; Giesy, John P

    2013-01-01

    As part of an ongoing study of the status and trends of contaminants in the Yellow Sea, during May of 2009, the concentrations of perfluorinated compounds (PFCs) were determined in water (n=15), sediment (n=12), soil (n=13), and biota (n=74) from estuarine and coastal areas along the west coast of Korea. Of the 12PFCs monitored, PFOS and PFOA were the most frequently detected compounds in water. Greater concentrations of PFCs were found in waters from the inner regions of sea dikes in three artificial lakes, Shihwa, Asan, and Sapgyo, than outer regions. Concentrations were also comparable in two estuarine areas, which indicated that most PFCs in coastal areas originated from industrial and local regions and river water flowing through estuaries. Concentrations of PFCs in soils and sediments were generally less than limits of quantification and were generally less than those measured in biota. Compound-specific bioaccumulation of PFBS and PFOS had the greatest BCF values in crab, while in fish it was PFOS and PFDA, and in gastropods and bivalves it was PFHxS. Distributions of BCFs for PFOS in body-parts of crab showed the greatest values in soft tissues followed by shells and then legs. Distribution among tissues and organs of fishes was more variable than those observed for crab. When compared to a similar study conducted by our group in 2008, concentrations of PFCs in water samples were significantly less in 2009. However, there was little change in bioconcentration from sediments into benthic organisms. Finally, we conducted the assessment of potential adverse effects for PFCs on aquatic life by use of current and previous reported data.

  14. Interaction Of Mesoscale Convective Systems With The Land - Sea Breezes Along The Guinea Coast Of West Africa

    NASA Astrophysics Data System (ADS)

    Coulibaly, A.; Omotosho, B. J.; Sylla, M. B.; Fink, A. H.

    2015-12-01

    1-3 hourly METARS/SYNOP observation data of wind (speed and direction), air temperature over land, covering the period 1983-2012, were used in order to characterize land-sea breezes (LSB) over five coastline stations (Abidjan, Accra, Lomé, Cotonou and Ikeja-Lagos) in the Guinean Coast, West Africa. In additional to this, 8 years (2003-2010) sea surface temperature (SST) data from adjacent Atlantic Ocean and monthly METARS/SYNOP observation data of precipitation (1983-2012) were also used. Based on wind speed and direction, the wind roses of all months over all stations have been plotted. These wind roses reveal that, globally, the northerly winds occurred rarely for the months of February, March, and April at Cotonou (Benin Republic).This is seen for other stations (Lomé and Accra). The night/morning time northerly winds appear at all stations, except Accra where there is no northerly wind or is very weak. According to the stations basis, the period of that night/morning northerly winds varies, except in summer period (July - September), where the normal s/w monsoon winds can weaken override at all stations. Set criteria based on the diurnal reversal of wind direction, and the thermal gradient necessary to drive the wind circulation, was used to identify land-sea breeze days. On station-wide basis, sea-breezes occur, at least all period of year, but less frequent in the summer months, where the minimum value of monthly mean temperature gradient is observed for selected stations.

  15. Estimating Limit Reference Points for Western Pacific Leatherback Turtles (Dermochelys coriacea) in the U.S. West Coast EEZ.

    PubMed

    Curtis, K Alexandra; Moore, Jeffrey E; Benson, Scott R

    2015-01-01

    Biological limit reference points (LRPs) for fisheries catch represent upper bounds that avoid undesirable population states. LRPs can support consistent management evaluation among species and regions, and can advance ecosystem-based fisheries management. For transboundary species, LRPs prorated by local abundance can inform local management decisions when international coordination is lacking. We estimated LRPs for western Pacific leatherbacks in the U.S. West Coast Exclusive Economic Zone (WCEEZ) using three approaches with different types of information on local abundance. For the current application, the best-informed LRP used a local abundance estimate derived from nest counts, vital rate information, satellite tag data, and fishery observer data, and was calculated with a Potential Biological Removal estimator. Management strategy evaluation was used to set tuning parameters of the LRP estimators to satisfy risk tolerances for falling below population thresholds, and to evaluate sensitivity of population outcomes to bias in key inputs. We estimated local LRPs consistent with three hypothetical management objectives: allowing the population to rebuild to its maximum net productivity level (4.7 turtles per five years), limiting delay of population rebuilding (0.8 turtles per five years), or only preventing further decline (7.7 turtles per five years). These LRPs pertain to all human-caused removals and represent the WCEEZ contribution to meeting population management objectives within a broader international cooperative framework. We present multi-year estimates, because at low LRP values, annual assessments are prone to substantial error that can lead to volatile and costly management without providing further conservation benefit. The novel approach and the performance criteria used here are not a direct expression of the "jeopardy" standard of the U.S. Endangered Species Act, but they provide useful assessment information and could help guide international

  16. Bacterial production, glucosidase activity and particle-associated carbohydrates in Dona Paula bay, west coast of India

    NASA Astrophysics Data System (ADS)

    Bhaskar, P. V.; Bhosle, N. B.

    2008-11-01

    Size-fractionated bacterial production, abundance and α- and β- glucosidase enzyme activities were studied with respect to changes in hydrography, total suspended matter (TSM), chlorophyll a, particulate organic carbon and nitrogen ratio (POC:PON), 1.5 M NaCl-soluble and 10 mM EDTA-soluble carbohydrates (Sal-PCHO and CPCHO) and transparent exopolymeric particles (TEP) in the surface waters from July 1999-2000 at a shallow coastal station in Dona Paula Bay, west coast of India. The bulk of the total bacterial production and glucosidase activity were associated with particles (75% and >80%, respectively). Total bacterial production was linearly correlated to chlorophyll a ( r = 0.513; p < 0.05) whereas enzyme activity was significantly correlated to TSM (α-glucosidase: r = 0.721 ( p < 0.001); β-glucosidase: r = 0.596 ( p < 0.01)). Both α-glucosidase ( r = 0.514; p < 0.05) and β-glucosidase enzymes ( r = 0.598; p < 0.01) appeared to be involved in the degradation of CPCHO and Sal-PCHO, respectively. Changes in α-glucosidase/β-glucosidase ratios highlighted the varying composition of particulate organic matter. The bacterial uptake of 14C-labeled bacterial extracellular carbohydrate measured over 11 days showed a strong linear correlation between 14C-uptake and bacterial production using tritiated thymidine. The turnover rate of 14C-labeled carbohydrate-C was 0.52 d -1, higher than the estimated annual mean potential carbohydrate carbon turnover rate of 0.33 ± 0.2 d -1. Our study suggests that carbohydrates derived from sediments may serve as an important alternative carbon source sustaining the bacterial carbon demand in the surface waters of Dona Paula Bay.

  17. Seasonal variability of carbon dioxide and methane in the rivers and lagoons of Ivory Coast (West Africa)

    NASA Astrophysics Data System (ADS)

    Koné, Y. J. M.; Abril, G.; Delille, B.; Borges, A. V.

    2009-04-01

    We report a data-set of carbon dioxide (CO2) and dissolved methane (CH4) in three rivers (Bia, Tanoé and Comoé) and five lagoons (Tendo, Aby, Ebrié, Potou and Grand-Lahou) of Ivory Coast (West Africa), during the four main climatic seasons (high dry season, high rainy season, low dry season and low rainy season). The surface waters of the three rivers were oversaturated in CO2 and CH4 with respect to atmospheric equilibrium, the seasonal variability of CO2 and CH4 seemed to be largely controlled by dilution during the flooding period. The strong correlation of CH4 concentrations with the partial pressure of CO2 (pCO2) confirm the dominance of a continental sources (from soils) for both CO2 and CH4 in these rivers. The largest CH4 over-saturations and diffusive air-water CH4 fluxes were observed in the Tendo and Aby lagoons that are permanently stratified systems (unlike the other 3 lagoons), leading to anoxic bottom waters favorable for a large CH4 production. In addition, these two stratified lagoons showed low pCO2 values due to high primary production, which suggests an efficient transfer of organic matter across the pycnocline. As a result, the stratified Tendo and Aby lagoons were respectively, a low source of CO2 to the atmosphere and a sink of atmospheric CO2 while the other 3 well-mixed lagoons were strong sources of CO2 to the atmosphere but lower sources of CH4 to the atmosphere.

  18. Shifts in condition and distribution of eastern North Pacific flatfish along the U.S. west coast (2003-2010)

    NASA Astrophysics Data System (ADS)

    Keller, Aimee A.; Bradburn, Mark J.; Simon, Victor H.

    2013-07-01

    Flatfish condition indices and distribution were examined along the U.S. west coast (55-1280 m) in relation to environmental variability and biomass using data from ten frequently occurring species collected in annual groundfish surveys from 2003 to 2010. The study was conducted during a period characterized by a cooling trend in the northern California Current system and by declining biomass for flatfish in general. Annual condition indices for six species (arrowtooth flounder, Dover sole, English sole, Pacific sanddab, petrale sole, and rex sole) were significantly related either to large-scale climatic indices (Pacific Decadal Oscillation, Multivariate El Niño-Southern Oscillation Index, North Pacific Gyre Oscillation) and/or annual biomass levels. Condition was most closely related to environmental effects rather than either biomass alone or both variables, with condition typically higher during cool climatic conditions. A similar analysis revealed that changes in distribution (measured as variation in annual catch-weighted mean latitude, longitude, depth and temperature) tended to be best described by models incorporating environmental effects and biomass rather than either variable alone. Linear trends in the center of distribution along a southeast-northwest axis were significant for seven species (arrowtooth flounder, deepsea sole, Dover sole, flathead sole, Pacific sanddab, petrale sole, and slender sole) with a tendency for flatfish to be displaced towards the southeast as environmental conditions shifted from warm to cooler conditions and biomass declined. A spatial distribution analysis indicated that for the majority of species (80%) the greatest magnitude of displacement (km) occurred when the centers of biomass were compared between environmental phases (average annual displacement 34 km) rather than changing biomass levels (average displacement 24 km). Taken together both approaches revealed that environmental changes and variation in biomass play

  19. Seasonal Dynamics of Phytoplankton and Environmental Factors around the Chagwi-do off the West Coast of Jeju Island, Korea

    NASA Astrophysics Data System (ADS)

    Affan, Abu; Lee, Joon-Baek; Kim, Jun-Teck; Choi, Young-Chan; Kim, Jong-Man; Myoung, Jung-Goo

    2007-06-01

    The dynamics of phytoplankton abundance with seasonal variation in physicochemical conditions were investigated monthly at 10 stations around the Chagwi-do off the west coast of Jeju Island, Korea, including inshore, middle shore, and offshore in the marine ranching area from September 2004 to November 2005. Water temperature varied from 12.1 to 28.9°C (average 18.8°C), and salinity from 28.9 to 34.9 psu (average 33.7 psu). The chlorophyll a concentration was 0.02-2.05 µg L1 (average 0.70 µg L1), and the maximum concentration occurred in the bottom layer in April. A total of 294 phytoplankton species belonging to 10 families was identified: 182 Bacillariophyceae, 52 Dinophyceae, 9 Chlorophyceae, 12 Cryptophyceae, 6 Chrysophyceae, 4 Dictyophyceae, 13 Euglenophyceae, 6 Prymnesiophyceae, 5 Prasinophyceae, and 5 Raphidophyceae. The standing crop was 2.21-48.69x104 cells L1 (average 9.23x 104 cells L1), and the maximum occurred in the bottom layer in April. Diatoms were most abundant throughout the year, followed by dinoflagellates and phytoflagellates. A phytoplankton bloom occurred twice: once in spring, peaking in April, and once in autumn, peaking in November. The spring bloom was represented by four Chaetoceros species and Skeletonema costatum; each contributed 10-20% of the total phytoplankton abundance. The autumn bloom comprised dinoflagellates, diatoms, and phytoflagellates, of which dinoflagellates were predominant. Gymnodinium conicum, Prorocentrum micans, and P. triestinum each contributed over 10% of the total phytoplankton abundance.

  20. Assessment of well water quality in Tsunami affected regions of south-west coast of Kerala, India.

    PubMed

    Nair, G Achuthan; Chandran, R Pratap; Sukumar, B; Santhosh, S; Vijayamohanan; Sobha, V

    2013-07-01

    The quality of well waters, based on 23 parameters of water, at 12 stations of south-west coast of Kerala, India, was assessed during monsoon, 2009 and summer, 2010, to determine their suitability for drinking and other domestic purposes. The stations selected were grouped into four regions viz. least, slightly, moderately and severely affected ones based on the severity of 2004 Asian Tsunami at each station. The depths of wells showed variations depending on the seasons and on their distance from the seacoast. The average water temperatures during monsoon and summer seasons were 28.5 degrees C and 30.2 degrees C respectively. The pH of well waters were below 6.5 in least and slightly affected regions and above this value in moderately and severely affected regions. In all the four regions, the well water parameters of electrical conductivity, hardness, fluoride, free chlorine, copper, zinc, calcium and nickel were below, and phosphorus, lead, iron cadmium and manganese were above the standard permissible levels set for them in drinking water. The values of salinity, sodium and potassium in the well waters of moderately and severely affected regions, and the values of nitrate-nitrogen, nitrate and magnesium in the well waters of severely affected regions were above the permissible limits set for them in drinking water. Water quality index calculated on the basis of drinking water standards revealed that the well waters of least and slightly affected regions were moderately polluted in both monsoon and summer seasons and the same of moderately affected region were excessively polluted during monsoon and severely polluted during summer seasons, whereas the well waters of severely affected regions were severely polluted in both seasons. Suitable recommendations were made to improve the quality of well waters of least and slightly affected regions.

  1. Estimating Limit Reference Points for Western Pacific Leatherback Turtles (Dermochelys coriacea) in the U.S. West Coast EEZ

    PubMed Central

    Curtis, K. Alexandra; Moore, Jeffrey E.; Benson, Scott R.

    2015-01-01

    Biological limit reference points (LRPs) for fisheries catch represent upper bounds that avoid undesirable population states. LRPs can support consistent management evaluation among species and regions, and can advance ecosystem-based fisheries management. For transboundary species, LRPs prorated by local abundance can inform local management decisions when international coordination is lacking. We estimated LRPs for western Pacific leatherbacks in the U.S. West Coast Exclusive Economic Zone (WCEEZ) using three approaches with different types of information on local abundance. For the current application, the best-informed LRP used a local abundance estimate derived from nest counts, vital rate information, satellite tag data, and fishery observer data, and was calculated with a Potential Biological Removal estimator. Management strategy evaluation was used to set tuning parameters of the LRP estimators to satisfy risk tolerances for falling below population thresholds, and to evaluate sensitivity of population outcomes to bias in key inputs. We estimated local LRPs consistent with three hypothetical management objectives: allowing the population to rebuild to its maximum net productivity level (4.7 turtles per five years), limiting delay of population rebuilding (0.8 turtles per five years), or only preventing further decline (7.7 turtles per five years). These LRPs pertain to all human-caused removals and represent the WCEEZ contribution to meeting population management objectives within a broader international cooperative framework. We present multi-year estimates, because at low LRP values, annual assessments are prone to substantial error that can lead to volatile and costly management without providing further conservation benefit. The novel approach and the performance criteria used here are not a direct expression of the “jeopardy” standard of the U.S. Endangered Species Act, but they provide useful assessment information and could help guide

  2. Estimating Limit Reference Points for Western Pacific Leatherback Turtles (Dermochelys coriacea) in the U.S. West Coast EEZ.

    PubMed

    Curtis, K Alexandra; Moore, Jeffrey E; Benson, Scott R

    2015-01-01

    Biological limit reference points (LRPs) for fisheries catch represent upper bounds that avoid undesirable population states. LRPs can support consistent management evaluation among species and regions, and can advance ecosystem-based fisheries management. For transboundary species, LRPs prorated by local abundance can inform local management decisions when international coordination is lacking. We estimated LRPs for western Pacific leatherbacks in the U.S. West Coast Exclusive Economic Zone (WCEEZ) using three approaches with different types of information on local abundance. For the current application, the best-informed LRP used a local abundance estimate derived from nest counts, vital rate information, satellite tag data, and fishery observer data, and was calculated with a Potential Biological Removal estimator. Management strategy evaluation was used to set tuning parameters of the LRP estimators to satisfy risk tolerances for falling below population thresholds, and to evaluate sensitivity of population outcomes to bias in key inputs. We estimated local LRPs consistent with three hypothetical management objectives: allowing the population to rebuild to its maximum net productivity level (4.7 turtles per five years), limiting delay of population rebuilding (0.8 turtles per five years), or only preventing further decline (7.7 turtles per five years). These LRPs pertain to all human-caused removals and represent the WCEEZ contribution to meeting population management objectives within a broader international cooperative framework. We present multi-year estimates, because at low LRP values, annual assessments are prone to substantial error that can lead to volatile and costly management without providing further conservation benefit. The novel approach and the performance criteria used here are not a direct expression of the "jeopardy" standard of the U.S. Endangered Species Act, but they provide useful assessment information and could help guide international

  3. Dependence of Wind Turbine Curves on Atmospheric Stability Regimes - An Analysis of a West Coast North American Tall Wind Farm

    SciTech Connect

    Wharton, S; Lundquist, J K; Sharp, J; Zulauf, M

    2009-08-24

    Tall wind turbines, with hub heights at 80 m or above, can extract large amounts of energy from the atmosphere because they are likely to encounter higher wind speeds, but they face challenges given the complex nature of wind flow in the boundary layer. Depending on whether the boundary layer is stable, convective or neutral, mean wind speed (U) and turbulence ({sigma}{sub U}) may vary greatly across the tall turbine swept area (40 m to 120 m). This variation can cause a single turbine to produce difference amounts of power during time periods of identical hub height wind speeds. The study examines the influence that atmospheric mixing or stability has on power output at a West Coast North American wind farm. They first examine the accuracy and applicability of two, relatively simple stability parameters, the wind shear-exponent, {alpha}, and the turbulence intensity, I{sub u}, against the physically-based, Obukhov length, L, to describe the wind speed and turbulence profiles in the rotor area. In general, the on-site stability parameters {alpha} and I{sub u} are in high agreement with the off-site, L stability scale parameter. Next, they divide the measurement period into five stability classes (strongly stable, stable, neutral, convective, and strongly convective) to discern stability-effects on power output. When only the mean wind speed profile is taken into account, the dependency of power output on boundary layer stability is only subtly apparent. When turbulence intensity I{sub u} is considered, the power generated for a given wind speed is twenty percent higher during strongly stable conditions than during strongly convective conditions as observed in the spring and summer seasons at this North American wind farm.

  4. Abundance and Size Distribution of the Sacoglossan Elysia viridis on Co-Occurring Algal Hosts on the Swedish West Coast

    PubMed Central

    Baumgartner, Finn A.; Toth, Gunilla B.

    2014-01-01

    Sacoglossans are specialized marine herbivores that tend to have a close evolutionary relationship with their macroalgal hosts, but the widely distributed species Elysia viridis can associate with several algal species. However, most previous investigations on the field abundance and size distribution of E. viridis have focussed on Codium spp. in the British Isles, and algae from this genus are considered superior hosts for E. viridis. In the present study, we investigated the abundance and size distribution of E. viridis on 6 potential host algae with differing morphologies (the septate species Cladophora sericea, Cladophora rupestris, Chaetomorpha melagonium, and Ceramium virgatum, as well as the siphonaceous species Codium fragile and Bryopsis sp.) at 2 sites on the Swedish west coast over the course of a year. In spring, slugs were almost absent from all algal hosts. In summer and autumn, E. viridis consistently occurred on several of the algal species at both sites. The highest number of small E. viridis were found on C. sericea, intermediate numbers of significantly larger E. viridis were found on C. rupestris, while fewer, intermediate sized animals were found on C. fragile. Throughout the study period, only a few E. viridis individuals were found on C. melagonium, Bryopsis sp., and C. virgatum. Our results indicate that E. viridis is an annual species in Sweden, capable of exploiting co-occurring congeneric and intergeneric algal hosts with differing morphologies. These results corroborate previous findings that E. viridis can exploit several different algal species, but does not indicate that C. fragile is a superior host. PMID:24647524

  5. Interannual vs decadal SST forced responses of the West African monsoon

    NASA Astrophysics Data System (ADS)

    Rodríguez-Fonseca, Belen

    2010-05-01

    One of the strongest interdecadal signals on the planet has been observed in the Sahelian rainfall during the second half of the XXth century, from wet conditions in the 50's and 60's to drier conditions after the 70's. Parallel to this, several decadal signals have experienced a change from the 70's, and also the influence of the global warming has increased from this decade. From a global perspective the West African rainfall variability is highly modulated by SST forced signals. Many works have pointed out to the Atlantic and Pacific equatorial modes influence on interannual timescales; and to the AMO and the Pacific and Indian Ocean at multidecadal timescales. In the AMMA-EU context the modulation of the interannual modes by the decadal variability together with the influence of the GW has been studied by analysing the interannual modes of variability before and after the 70's. The results indicate the presence of different interannual telecconections between these two periods and, hence, of different anomalous rainfall responses. The importance of the background state modulated by multidecadal variability in the interannual modes is stated in this work. Also, an interesting discussion appears if we wonder whether or not the background state is affected, in turn, by anthropogenic climate change. Recent observational and GCM studies have shown, following the results of Polo et al. (2008), how the Atlantic and Pacific Niños present a dynamical link during the last decades of the XX century (Rodriguez-Fonseca et al., 2009). In this way, the positive (negative) phase of the summer Pacific Niño signal has been found to be connected with a negative (positive) phase of the Equatorial Atlantic mode (EM or Atlantic Niño, Polo et al., 2008); a pattern which leads the summer Atlantic variability. The determinant impact of this connection on the WA monsoon has been addressed by defining a global summer tropical mode accounting for more than the 60% of the rainfall

  6. Missionary Education in West Africa: A Study of Pedagogical Ambition

    ERIC Educational Resources Information Center

    Ustorf, Werner

    2011-01-01

    The history of the North German Mission Society (established 1836 in Hamburg) and its activity on the West African coast (from 1847 onwards among the Ewe, in what is now Ghana and Togo where it was and still is known as the "Bremen Mission") mirrors neatly the various phases of the idea of "mission": its composite motivation (Enlightenment,…

  7. Evaluation of consumer acceptance of west coast versus east coast-produced broccoli through sensory analysis of quality rating factors and nutritionally important metabolites

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Production trials and germplasm evaluation of broccoli (Brassica oleracea var. italica) developed for eastern U.S. production conditions have identified lines and cultivars that are better adapted to more stressful, variable East Coast environments. As a part of this work sponsored by the USDA SCIR...

  8. United States West Coast

    NASA Technical Reports Server (NTRS)

    2002-01-01

    On Thursday (Feb. 14, 2002), the cloud cover that often overshadows the western United States this time of year broke to provide those at the Olympic Games with a beautiful day. The nearly cloud-free day was captured by the Moderate-resolution Imaging Spectroradiometer (MODIS), flying aboard NASAs Terra spacecraft. A thick layer of snow blankets northernmost Nevada, northern Utah, most of Idaho and western Wyoming. The snow surrounds and highlights Utahs Great Salt Lake. Just south of the lake, clouds can be seen hovering over southern Utah. (In general, clouds appear streaky and uneven on a satellite image, and snow cover appears solid with definable borders.) North of the Great Salt Lake, one can clearly discern the light gray Northern Rocky Mountains cutting through Idaho and up into Canada. Moving southwest, the spine-like Sierra Nevada mountains separate the greenery of Southern California from the brown deserts of Arizona and Nevada. Credit: Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC

  9. 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.

  10. Cloning of a prothrombin activator-like metalloproteinase from the West African saw-scaled viper, Echis ocellatus.

    PubMed

    Hasson, S S; Theakston, R D G; Harrison, R A

    2003-11-01

    Systemic envenoming by the saw-scaled viper, Echis ocellatus, is responsible for more deaths than any other snake in West Africa. Despite its medical importance, there have been few investigations into the toxin composition of the venom of this viper. Here we describe the isolation of E. ocellatus venom gland cDNAs encoding a protein of 514 amino acids that showed 91% sequence similarity to Ecarin, a prothrombin-activating metalloproteinase from the venom of the East African viper, E. pyramidum leakeyi, that induces severe consumption coagulopathy. Structural similarities between the E. ocellatus metalloproteinase and analogues in venoms of related vipers suggest that antibodies raised to phylogenetically conserved E. ocellatus metalloproteinase domains may have potential for cross-specific and cross-generic neutralisation of analogous venom toxins. PMID:14602118

  11. Biogeochemical trace gas and oxygen concentration signatures from the West African upwelling areas as observed at the Cape Verde Atmospheric Observatory (CVAO)

    NASA Astrophysics Data System (ADS)

    Kozlova, E.; Fiedler, B.; Leppert, R.; Seifert, T.; Neves, L.; Heimann, M.

    2011-12-01

    We present 3-year records of atmospheric concentrations of trace gases (CO2, CH4, CO, N2O, and SF6), and oxygen at the Cape Verde Atmospheric Observatory (CVAO). The Observatory is located on Sao Vicente Island in the north-eastern subtropical Atlantic (16.86° N, 24.87° W), and was first established within the frame of the Surface Ocean Lower Atmosphere project (SOLAS). The air is sampled from a 30-m tower. The analytical system is automated and samples air continuously (16 min for every O2 and CO2 measurement and 12 min for the rest of the species (Kozlova and Manning, 2009)). In addition, air flask samples are collected biweekly and subsequently analyzed at the Max-Planck Institute for Biogeochemistry. The Cape Verde Atmospheric Observatory is located in the North Atlantic trade wind system. We analyse the composition of marine boundary layer air masses that often have passed over the coastal upwelling areas off the coast of Western Sahara and Mauritania. These upwelling waters are supersaturated in CO2, CH4, and partly in N2O, and undersaturated in oxygen. Small shifts in the wind trajectories are reflected in synoptic variations of the atmospheric concentrations depending on the travel time of the air mass over the upwelling region. Using a footprint analysis with an atmospheric backtrajectory model, we analyse and quantify the integrated contribution of surface ocean gas exchange from these areas. We can place bounds on the gas exchange coefficient in the upwelling area by combining the flux estimates with in situ measurements of dissolved surface ocean oxygen from autonomous gliders (taken as part of the SOPRAN project) and remotely sensed ocean chlorophyll data (ocean color). The location of the Observatory provides a unique opportunity for monitoring long-term changes in spatially integrated marine productivity and oxygen depletion in the upwelling area of the West African Coast. Kozlova, E. A., and A. C. Manning, Methodology and calibration for

  12. Atmospheric Stability Impacts on Power Curves of Tall Wind Turbines - An Analysis of a West Coast North American Wind Farm

    SciTech Connect

    Wharton, S; Lundquist, J K

    2010-02-22

    Tall wind turbines, with hub heights at 80 m or above, can extract large amounts of energy from the atmosphere because they are likely to encounter higher wind speeds, but they face challenges given the complex nature of wind flow and turbulence at these heights in the boundary layer. Depending on whether the boundary layer is stable, neutral, or convective, the mean wind speed, direction, and turbulence properties may vary greatly across the tall turbine swept area (40 to 120 m AGL). This variability can cause tall turbines to produce difference amounts of power during time periods with identical hub height wind speeds. Using meteorological and power generation data from a West Coast North American wind farm over a one-year period, our study synthesizes standard wind park observations, such as wind speed from turbine nacelles and sparse meteorological tower observations, with high-resolution profiles of wind speed and turbulence from a remote sensing platform, to quantify the impact of atmospheric stability on power output. We first compare approaches to defining atmospheric stability. The standard, limited, wind farm operations enable the calculation only of a wind shear exponent ({alpha}) or turbulence intensity (I{sub U}) from cup anemometers, while the presence at this wind farm of a SODAR enables the direct observation of turbulent kinetic energy (TKE) throughout the turbine rotor disk. Additionally, a nearby research meteorological station provided observations of the Obukhov length, L, a direct measure of atmospheric stability. In general, the stability parameters {alpha}, I{sub U}, and TKE are in high agreement with the more physically-robust L, with TKE exhibiting the best agreement with L. Using these metrics, data periods are segregated by stability class to investigate power performance dependencies. Power output at this wind farm is highly correlated with atmospheric stability during the spring and summer months, while atmospheric stability exerts

  13. Constraining regional scale carbon budgets at the US West Coast using a high-resolution atmospheric inverse modeling approach

    NASA Astrophysics Data System (ADS)

    Goeckede, M.; Michalak, A. M.; Vickers, D.; Turner, D.; Law, B.

    2009-04-01

    The study presented is embedded within the NACP (North American Carbon Program) West Coast project ORCA2, which aims at determining the regional carbon balance of the US states Oregon, California and Washington. Our work specifically focuses on the effect of disturbance history and climate variability, aiming at improving our understanding of e.g. drought stress and stand age on carbon sources and sinks in complex terrain with fine-scale variability in land cover types. The ORCA2 atmospheric inverse modeling approach has been set up to capture flux variability on the regional scale at high temporal and spatial resolution. Atmospheric transport is simulated coupling the mesoscale model WRF (Weather Research and Forecast) with the STILT (Stochastic Time Inverted Lagrangian Transport) footprint model. This setup allows identifying sources and sinks that influence atmospheric observations with highly resolved mass transport fields and realistic turbulent mixing. Terrestrial biosphere carbon fluxes are simulated at spatial resolutions of up to 1km and subdaily timesteps, considering effects of ecoregion, land cover type and disturbance regime on the carbon budgets. Our approach assimilates high-precision atmospheric CO2 concentration measurements and eddy-covariance data from several sites throughout the model domain, as well as high-resolution remote sensing products (e.g. LandSat, MODIS) and interpolated surface meteorology (DayMet, SOGS, PRISM). We present top-down modeling results that have been optimized using Bayesian inversion, reflecting the information on regional scale carbon processes provided by the network of high-precision CO2 observations. We address the level of detail (e.g. spatial and temporal resolution) that can be resolved by top-down modeling on the regional scale, given the uncertainties introduced by various sources for model-data mismatch. Our results demonstrate the importance of accurate modeling of carbon-water coupling, with the

  14. Benthic fish and invertebrate assemblages within the National Marine Fisheries Service US west coast triennial bottom trawl survey

    NASA Astrophysics Data System (ADS)

    Zimmermann, Mark

    2006-06-01

    This project sought to derive the ecological boundaries within a bottom trawl survey by treating benthic fish and invertebrate species as biological indicators in assemblage analyses. A secondary goal was to determine if these ecological boundaries match the strata boundaries of the bottom trawl survey. Most fishery-independent bottom trawl surveys are driven by management needs for relative biomass estimation of commercial stocks within certain strata, and the strata boundaries are often abiotic features such as political borders, capes and submarine canyons, or arbitrary depths. However, these surveys also generate a great deal of under-utilized data—such as the abundance of non-commercial benthic species and the occurrence of size-groups of commercial species—that can be used for defining ecological boundaries that are independent of the strata boundaries. For an example data set, this analysis used the National Marine Fisheries Service US west coast bottom trawl survey, which has sampled the same 610 stations in three surveys (1995, 1998, and 2001). This analysis determined the geographic extent of three biologically distinct assemblages which occurred in a total of 9 analyses across three bottom trawl surveys and across three assemblage analysis methods: hierarchical clustering, detrended correspondence analysis (DCA), and non-metric multidimensional scaling (NMS). Most trawl survey stations were consistently grouped into the same assemblage in a majority of the 9 analyses, indicating that the assemblages were stable with respect to time and to interpretation from the different assemblage analyses. Kriging on the percent agreement of the 9 analyses at each station defined boundaries of agreement (edges of assemblages), areas of disagreement (transition zones between assemblages), and clear differences from the arbitrary latitude/depth bottom trawl survey stratification scheme. The temporal and statistical consistency, and the geographical continuity of the

  15. The West African ebola virus disease epidemic 2014-2015: A commissioned review.

    PubMed

    Omilabu, S A; Salu, O B; Oke, B O; James, A B

    2016-01-01

    The first epidemic of Ebola haemorrhagic disease in West Africa is the largest and longest Ebola epidemic till date, where the outbreak notably involved three countries with distant spread to other countries. It has caused significant mortality, with reported case fatality rates of up to 70%. Data and relevant information were extracted from the review of majorly relevant publications/papers about the Ebola epidemic in West Africa and other previous outbreaks of Ebola virus (EBOV). As of 2016, with the epidemic under control, the World Health Organization has warned that flare-ups of the disease are likely to continue for some time as recently occurred in Sierra Leone and the on-going in Guinea. As this may not be the last outbreak of Ebola virus disease (EVD) in West Africa, there is a need to focus on diagnostic and research capacity required to curtail EVD with adequate measures for emergency preparedness and policies for innovative treatment strategies. PMID:27424613

  16. Bacillus anthracis Diversity and Geographic Potential across Nigeria, Cameroon and Chad: Further Support of a Novel West African Lineage

    PubMed Central

    Blackburn, Jason K.; Odugbo, Moses Ode; Van Ert, Matthew; O’Shea, Bob; Mullins, Jocelyn; Perrenten, Vincent; Maho, Angaya; Hugh-Jones, Martin; Hadfield, Ted

    2015-01-01

    Zoonoses, diseases affecting both humans and animals, can exert tremendous pressures on human and veterinary health systems, particularly in resource limited countries. Anthrax is one such zoonosis of concern and is a disease requiring greater public health attention in Nigeria. Here we describe the genetic diversity of Bacillus anthracis in Nigeria and compare it to Chad, Cameroon and a broader global dataset based on the multiple locus variable number tandem repeat (MLVA-25) genetic typing system. Nigerian B. anthracis isolates had identical MLVA genotypes and could only be resolved by measuring highly mutable single nucleotide repeats (SNRs). The Nigerian MLVA genotype was identical or highly genetically similar to those in the neighboring countries, confirming the strains belong to this unique West African lineage. Interestingly, sequence data from a Nigerian isolate shares the anthrose deficient genotypes previously described for strains in this region, which may be associated with vaccine evasion. Strains in this study were isolated over six decades, indicating a high level of temporal strain stability regionally. Ecological niche models were used to predict the geographic distribution of the pathogen for all three countries. We describe a west-east habitat corridor through northern Nigeria extending into Chad and Cameroon. Ecological niche models and genetic results show B. anthracis to be ecologically established in Nigeria. These findings expand our understanding of the global B. anthracis population structure and can guide regional anthrax surveillance and control planning. PMID:26291625

  17. Bacillus anthracis Diversity and Geographic Potential across Nigeria, Cameroon and Chad: Further Support of a Novel West African Lineage.

    PubMed

    Blackburn, Jason K; Odugbo, Moses Ode; Van Ert, Matthew; O'Shea, Bob; Mullins, Jocelyn; Perreten, Vincent; Perrenten, Vincent; Maho, Angaya; Hugh-Jones, Martin; Hadfield, Ted

    2015-01-01

    Zoonoses, diseases affecting both humans and animals, can exert tremendous pressures on human and veterinary health systems, particularly in resource limited countries. Anthrax is one such zoonosis of concern and is a disease requiring greater public health attention in Nigeria. Here we describe the genetic diversity of Bacillus anthracis in Nigeria and compare it to Chad, Cameroon and a broader global dataset based on the multiple locus variable number tandem repeat (MLVA-25) genetic typing system. Nigerian B. anthracis isolates had identical MLVA genotypes and could only be resolved by measuring highly mutable single nucleotide repeats (SNRs). The Nigerian MLVA genotype was identical or highly genetically similar to those in the neighboring countries, confirming the strains belong to this unique West African lineage. Interestingly, sequence data from a Nigerian isolate shares the anthrose deficient genotypes previously described for strains in this region, which may be associated with vaccine evasion. Strains in this study were isolated over six decades, indicating a high level of temporal strain stability regionally. Ecological niche models were used to predict the geographic distribution of the pathogen for all three countries. We describe a west-east habitat corridor through northern Nigeria extending into Chad and Cameroon. Ecological niche models and genetic results show B. anthracis to be ecologically established in Nigeria. These findings expand our understanding of the global B. anthracis population structure and can guide regional anthrax surveillance and control planning.

  18. The Impact of the Atlantic Cold Tongue on West African Monsoon Onset in Regional Model Simulations for 1998-2002

    NASA Technical Reports Server (NTRS)

    Druyan, Leonard M.; Fulakeza, Matthew B.

    2014-01-01

    The Atlantic cold tongue (ACT) develops during spring and early summer near the Equator in the Eastern Atlantic Ocean and Gulf of Guinea. The hypothesis that the ACT accelerates the timing of West African monsoon (WAM) onset is tested by comparing two regional climate model (RM3) simulation ensembles. Observed sea surface temperatures (SST) that include the ACT are used to force a control ensemble. An idealized, warm SST perturbation is designed to represent lower boundary forcing without the ACT for the experiment ensemble. Summer simulations forced by observed SST and reanalysis boundary conditions for each of five consecutive years are compared to five parallel runs forced by SST with the warm perturbation. The article summarizes the sequence of events leading to the onset of the WAM in the Sahel region. The representation of WAM onset in RM3 simulations is examined and compared to Tropical Rainfall Measuring Mission (TRMM), Global Precipitation Climatology Project (GPCP) and reanalysis data. The study evaluates the sensitivity of WAM onset indicators to the presence of the ACT by analysing the differences between the two simulation ensembles. Results show that the timing of major rainfall events and therefore theWAM onset in the Sahel are not sensitive to the presence of the ACT. However, the warm SST perturbation does increase downstream rainfall rates over West Africa as a consequence of enhanced specific humidity and enhanced northward moisture flux in the lower troposphere.

  19. Measuring pesticide ecological and health risks in West African agriculture to establish an enabling environment for sustainable intensification

    PubMed Central

    Jepson, P. C.; Guzy, M.; Blaustein, K.; Sow, M.; Sarr, M.; Mineau, P.; Kegley, S.

    2014-01-01

    We outline an approach to pesticide risk assessment that is based upon surveys of pesticide use throughout West Africa. We have developed and used new risk assessment models to provide, to our knowledge, the first detailed, geographically extensive, scientifically based analysis of pesticide risks for this region. Human health risks from dermal exposure to adults and children are severe enough in many crops to require long periods of up to three weeks when entry to fields should be restricted. This is impractical in terms of crop management, and regulatory action is needed to remove these pesticides from the marketplace. We also found widespread risks to terrestrial and aquatic wildlife throughout the region, and if these results were extrapolated to all similar irrigated perimeters in the Senegal and Niger River Basins, they suggest that pesticides could pose a significant threat to regional biodiversity. Our analyses are presented at the regional, national and village levels to promote regulatory advances but also local risk communication and management. Without progress in pesticide risk management, supported by participatory farmer education, West African agriculture provides a weak context for the sustainable intensification of agricultural production or for the adoption of new crop technologies. PMID:24535399

  20. Measuring pesticide ecological and health risks in West African agriculture to establish an enabling environment for sustainable intensification.

    PubMed

    Jepson, P C; Guzy, M; Blaustein, K; Sow, M; Sarr, M; Mineau, P; Kegley, S

    2014-04-01

    We outline an approach to pesticide risk assessment that is based upon surveys of pesticide use throughout West Africa. We have developed and used new risk assessment models to provide, to our knowledge, the first detailed, geographically extensive, scientifically based analysis of pesticide risks for this region. Human health risks from dermal exposure to adults and children are severe enough in many crops to require long periods of up to three weeks when entry to fields should be restricted. This is impractical in terms of crop management, and regulatory action is needed to remove these pesticides from the marketplace. We also found widespread risks to terrestrial and aquatic wildlife throughout the region, and if these results were extrapolated to all similar irrigated perimeters in the Senegal and Niger River Basins, they suggest that pesticides could pose a significant threat to regional biodiversity. Our analyses are presented at the regional, national and village levels to promote regulatory advances but also local risk communication and management. Without progress in pesticide risk management, supported by participatory farmer education, West African agriculture provides a weak context for the sustainable intensification of agricultural production or for the adoption of new crop technologies.

  1. Measuring pesticide ecological and health risks in West African agriculture to establish an enabling environment for sustainable intensification.

    PubMed

    Jepson, P C; Guzy, M; Blaustein, K; Sow, M; Sarr, M; Mineau, P; Kegley, S

    2014-04-01

    We outline an approach to pesticide risk assessment that is based upon surveys of pesticide use throughout West Africa. We have developed and used new risk assessment models to provide, to our knowledge, the first detailed, geographically extensive, scientifically based analysis of pesticide risks for this region. Human health risks from dermal exposure to adults and children are severe enough in many crops to require long periods of up to three weeks when entry to fields should be restricted. This is impractical in terms of crop management, and regulatory action is needed to remove these pesticides from the marketplace. We also found widespread risks to terrestrial and aquatic wildlife throughout the region, and if these results were extrapolated to all similar irrigated perimeters in the Senegal and Niger River Basins, they suggest that pesticides could pose a significant threat to regional biodiversity. Our analyses are presented at the regional, national and village levels to promote regulatory advances but also local risk communication and management. Without progress in pesticide risk management, supported by participatory farmer education, West African agriculture provides a weak context for the sustainable intensification of agricultural production or for the adoption of new crop technologies. PMID:24535399

  2. Meteorological characteristics and overland precipitation impacts of atmospheric rivers affecting the West coast of North America based on eight years of SSM/I satellite observations

    USGS Publications Warehouse

    Neiman, P.J.; Ralph, F.M.; Wick, G.A.; Lundquist, J.D.; Dettinger, M.D.

    2008-01-01

    The pre-cold-frontal low-level jet within oceanic extratropical cyclones represents the lower-tropospheric component of a deeper corridor of concentrated water vapor transport in the cyclone warm sector. These corridors are referred to as atmospheric rivers (ARs) because they are narrow relative to their length scale and are responsible for most of the poleward water vapor transport at midlatitudes. This paper investigates landfalling ARs along adjacent north- and south-coast regions of western North America. Special Sensor Microwave Imager (SSM/ I) satellite observations of long, narrow plumes of enhanced integrated water vapor (IWV) were used to detect ARs just offshore over the eastern Pacific from 1997 to 2005. The north coast experienced 301 AR days, while the south coast had only 115. Most ARs occurred during the warm season in the north and cool season in the south, despite the fact that the cool season is climatologically wettest for both regions. Composite SSM/I IWV analyses showed landfalling wintertime ARs extending northeastward from the tropical eastern Pacific, whereas the summertime composites were zonally oriented and, thus, did not originate from this region of the tropics. Companion SSM/I composites of daily rainfall showed significant orographic enhancement during the landfall of winter (but not summer) ARs. The NCEP-NCAR global reanalysis dataset and regional precipitation networks were used to assess composite synoptic characteristics and overland impacts of landfalling ARs. The ARs possess strong vertically integrated horizontal water vapor fluxes that, on average, impinge on the West Coast in the pre-cold-frontal environment in winter and post-cold-frontal environment in summer. Even though the IWV in the ARs is greater in summer, the vapor flux is stronger in winter due to much stronger flows associated with more intense storms. The landfall of ARs in winter and north-coast summer coincides with anomalous warmth, a trough offshore, and

  3. West African monsoon dynamics inferred from abrupt fluctuations of Lake Mega-Chad

    PubMed Central

    Armitage, Simon J.; Bristow, Charlie S.; Drake, Nick A.

    2015-01-01

    From the deglacial period to the mid-Holocene, North Africa was characterized by much wetter conditions than today. The broad timing of this period, termed the African Humid Period, is well known. However, the rapidity of the onset and termination of the African Humid Period are contested, with strong evidence for both abrupt and gradual change. We use optically stimulated luminescence dating of dunes, shorelines, and fluviolacustrine deposits to reconstruct the fluctuations of Lake Mega-Chad, which was the largest pluvial lake in Africa. Humid conditions first occur at ∼15 ka, and by 11.5 ka, Lake Mega-Chad had reached a highstand, which persisted until 5.0 ka. Lake levels fell rapidly at ∼5 ka, indicating abrupt aridification across the entire Lake Mega-Chad Basin. This record provides strong terrestrial evidence that the African Humid Period ended abruptly, supporting the hypothesis that the African monsoon responds to insolation forcing in a markedly nonlinear manner. In addition, Lake Mega-Chad exerts strong control on global biogeochemical cycles because the northern (Bodélé) basin is currently the world’s greatest single dust source and possibly an important source of limiting nutrients for both the Amazon Basin and equatorial Atlantic. However, we demonstrate that the final desiccation of the Bodélé Basin occurred around 1 ka. Consequently, the present-day mode and scale of dust production from the Bodélé Basin cannot have occurred before 1 ka, suggesting that its role in fertilizing marine and terrestrial ecosystems is either overstated or geologically recent. PMID:26124133

  4. West African monsoon dynamics inferred from abrupt fluctuations of Lake Mega-Chad.

    PubMed

    Armitage, Simon J; Bristow, Charlie S; Drake, Nick A

    2015-07-14

    From the deglacial period to the mid-Holocene, North Africa was characterized by much wetter conditions than today. The broad timing of this period, termed the African Humid Period, is well known. However, the rapidity of the onset and termination of the African Humid Period are contested, with strong evidence for both abrupt and gradual change. We use optically stimulated luminescence dating of dunes, shorelines, and fluviolacustrine deposits to reconstruct the fluctuations of Lake Mega-Chad, which was the largest pluvial lake in Africa. Humid conditions first occur at ∼ 15 ka, and by 11.5 ka, Lake Mega-Chad had reached a highstand, which persisted until 5.0 ka. Lake levels fell rapidly at ∼ 5 ka, indicating abrupt aridification across the entire Lake Mega-Chad Basin. This record provides strong terrestrial evidence that the African Humid Period ended abruptly, supporting the hypothesis that the African monsoon responds to insolation forcing in a markedly nonlinear manner. In addition, Lake Mega-Chad exerts strong control on global biogeochemical cycles because the northern (Bodélé) basin is currently the world's greatest single dust source and possibly an important source of limiting nutrients for both the Amazon Basin and equatorial Atlantic. However, we demonstrate that the final desiccation of the Bodélé Basin occurred around 1 ka. Consequently, the present-day mode and scale of dust production from the Bodélé Basin cannot have occurred before 1 ka, suggesting that its role in fertilizing marine and terrestrial ecosystems is either overstated or geologically recent.

  5. Lake Mega-Chad, a West African Monsoon indicator and tipping element

    NASA Astrophysics Data System (ADS)

    Armitage, Simon; Bristow, Charlie; Drake, Nick

    2015-04-01

    From the deglacial period to the mid-Holocene, North Africa was characterised by much wetter conditions than today. The broad timing of this period, termed the African Humid Period, is well known. However, the rapidity of the onset and termination of the African Humid Period are contested, with strong evidence for both abrupt and gradual change. We use optically stimulated luminescence dating of dunes, shorelines and fluvio-lacustrine deposits to reconstruct the fluctuations of Lake Mega-Chad, which was the largest pluvial lake in Africa. Humid conditions first occur at ~15 ka, followed by a return to relatively arid conditions. By 11.5 ka Lake Mega-Chad had reached a highstand, which persisted until 5.0 ka. Lake levels fell rapidly at 5 ka, indicating abrupt aridification across the entire Lake Mega-Chad Basin. This record provides strong terrestrial evidence that the African Humid Period ended abruptly, supporting the hypothesis that the African monsoon responds to insolation forcing in a markedly non-linear manner. In addition, Lake Mega-Chad exerts strong control on global biogeochemical cycles since the northern (Bodélé) basin is currently the World's greatest single dust source, and possibly an important source of limiting nutrients for both the Amazon basin and equatorial Atlantic. However, we demonstrate that the final desiccation of the Bodélé Basin occurred around 1 ka. Consequently, the present-day mode and scale of dust production from Bodélé Basin cannot have occurred prior to 1 ka, suggesting that its role in fertilizing marine and terrestrial ecosystems is either overstated or geologically recent.

  6. Reviving the African wolf Canis lupus lupaster in North and West Africa: a mitochondrial lineage ranging more than 6,000 km wide.

    PubMed

    Gaubert, Philippe; Bloch, Cécile; Benyacoub, Slim; Abdelhamid, Adnan; Pagani, Paolo; Djagoun, Chabi Adéyèmi Marc Sylvestre; Couloux, Arnaud; Dufour, Sylvain

    2012-01-01

    The recent discovery of a lineage of gray wolf in North-East Africa suggests the presence of a cryptic canid on the continent, the African wolf Canis lupus lupaster. We analyzed the mtDNA diversity (cytochrome b and control region) of a series of African Canis including wolf-like animals from North and West Africa. Our objectives were to assess the actual range of C. l. lupaster, to further estimate the genetic characteristics and demographic history of its lineage, and to question its taxonomic delineation from the golden jackal C. aureus, with which it has been considered synonymous. We confirmed the existence of four distinct lineages within the gray wolf, including C. lupus/familiaris (Holarctic wolves and dogs), C. l. pallipes, C. l. chanco and C. l. lupaster. Taxonomic assignment procedures identified wolf-like individuals from Algeria, Mali and Senegal, as belonging to C. l. lupaster, expanding its known distribution c. 6,000 km to the west. We estimated that the African wolf lineage (i) had the highest level of genetic diversity within C. lupus, (ii) coalesced during the Late Pleistocene, contemporaneously with Holarctic wolves and dogs, and (iii) had an effective population size of c. 80,000 females. Our results suggest that the African wolf is a relatively ancient gray wolf lineage with a fairly large, past effective population size, as also suggested by the Pleistocene fossil record. Unique field observations in Senegal allowed us to provide a morphological and behavioral diagnosis of the African wolf that clearly distinguished it from the sympatric golden jackal. However, the detection of C. l. lupaster mtDNA haplotypes in C. aureus from Senegal brings the delineation between the African wolf and the golden jackal into question. In terms of conservation, it appears urgent to further characterize the status of the African wolf with regard to the African golden jackal. PMID:22900047

  7. Reviving the African Wolf Canis lupus lupaster in North and West Africa: A Mitochondrial Lineage Ranging More than 6,000 km Wide

    PubMed Central

    Gaubert, Philippe; Bloch, Cécile; Benyacoub, Slim; Abdelhamid, Adnan; Pagani, Paolo; Djagoun, Chabi Adéyèmi Marc Sylvestre; Couloux, Arnaud; Dufour, Sylvain

    2012-01-01

    The recent discovery of a lineage of gray wolf in North-East Africa suggests the presence of a cryptic canid on the continent, the African wolf Canis lupus lupaster. We analyzed the mtDNA diversity (cytochrome b and control region) of a series of African Canis including wolf-like animals from North and West Africa. Our objectives were to assess the actual range of C. l. lupaster, to further estimate the genetic characteristics and demographic history of its lineage, and to question its taxonomic delineation from the golden jackal C. aureus, with which it has been considered synonymous. We confirmed the existence of four distinct lineages within the gray wolf, including C. lupus/familiaris (Holarctic wolves and dogs), C. l. pallipes, C. l. chanco and C. l. lupaster. Taxonomic assignment procedures identified wolf-like individuals from Algeria, Mali and Senegal, as belonging to C. l. lupaster, expanding its known distribution c. 6,000 km to the west. We estimated that the African wolf lineage (i) had the highest level of genetic diversity within C. lupus, (ii) coalesced during the Late Pleistocene, contemporaneously with Holarctic wolves and dogs, and (iii) had an effective population size of c. 80,000 females. Our results suggest that the African wolf is a relatively ancient gray wolf lineage with a fairly large, past effective population size, as also suggested by the Pleistocene fossil record. Unique field observations in Senegal allowed us to provide a morphological and behavioral diagnosis of the African wolf that clearly distinguished it from the sympatric golden jackal. However, the detection of C. l. lupaster mtDNA haplotypes in C. aureus from Senegal brings the delineation between the African wolf and the golden jackal into question. In terms of conservation, it appears urgent to further characterize the status of the African wolf with regard to the African golden jackal. PMID:22900047

  8. Dyed and Printed Textiles: Javanese Batik [and] Dutch Wax Prints [and] West African Adire. Third Edition.

    ERIC Educational Resources Information Center

    Burke, Sue

    Three booklets focusing on dyed and printed textile techniques of Java, West Africa, and the Netherlands describe historical and ethnographic materials as well as the development of particular technical traditions. Each section may be used alone or with either or both of the others. When used together, these booklets illustrate the…

  9. Change and Variation in Family Religious Language Policy in a West African Muslim Community

    ERIC Educational Resources Information Center

    Moore, Leslie C.

    2016-01-01

    This article examines variation in family religious language policy in a Muslim community in West Africa. Taking an ethnographically grounded case study approach, I situate families' choices with regards to their children's religious (language) education within the larger linguistic, social, and cultural context, focusing on new influences on…

  10. Seasonal movements, migratory behavior, and site fidelity of West Indian manatees along the Atlantic coast of the United States

    USGS Publications Warehouse

    Deutsch, C.J.; Reid, J.P.; Bonde, R.K.; Easton, Dean E.; Kochman, H.I.; O'Shea, T.J.

    2003-01-01

    The West Indian manatee (Trichechus manatus) is endangered by human activities throughout its range, including the U.S. Atlantic coast where habitat degradation from coastal development and manatee deaths from watercraft collisions have been particularly severe. We radio-tagged and tracked 78 manatees along the east coast of Florida and Georgia over a 12-year period (1986-1998). Our goals were to characterize the seasonal movements, migratory behavior, and site fidelity of manatees in this region in order to provide information for the development of effective conservation strategies. Most study animals were tracked remotely with the Argos satellite system, which yielded a mean (SD) of 3.7 (1.6) locations per day; all were regularly tracked in the field using conventional radiotelemetry methods. The combined data collection effort yielded >93,000 locations over nearly 32,000 tag-days. The median duration of tracking was 8.3 months per individual, but numerous manatees were tracked over multiple years (max = 6.8 years). Most manatees migrated seasonally over large distances between a northerly warm-season range and a southerly winter range (median one-way distance = 280 km, max = 830 km), but 12% of individuals were resident in a relatively small area (2,300 km of coastline between southeastern Florida and Rhode Island. No study animals journeyed to the Gulf coast of Florida. Regions heavily utilized by tagged manatees included: Fernandina Beach, FL to Brunswick, GA in the warm season; northern Biscayne Bay to Port Everglades, FL in the winter; and central coastal Florida, especially the Banana River and northern Indian River lagoons, in all seasons. Daily travel rate, defined as the distance between successive mean daily locations, averaged 2.5 km (SD = 1.7), but this varied with season, migratory pattern, and sex. Adult males traveled a significantly greater distance per day than did adult females for most of the warm season, which corresponded closely with the

  11. Long-term fluctuations in Cystoseira populations along the west Istrian Coast (Croatia) related to eutrophication patterns in the northern Adriatic Sea.

    PubMed

    Iveša, Ljiljana; Djakovac, Tamara; Devescovi, Massimo

    2016-05-15

    An exploration of historical data suggested that eutrophication patterns might drive long-term fluctuations in Cystoseira populations along the west Istrian Coast (northern Adriatic Sea, Croatia). The regimes of northern Italian rivers, which flow approximately 100km west of the study area, mainly modulate the eutrophication levels of the northern Adriatic Sea. A regression of Cystoseira populations from the 1970s through the 1990s corresponded to increased levels of eutrophication in the study area. During the late 1990s, the density of sea urchins, which are efficacious macroalgal predators, decreased, likely due to an intense formation of pelagic mucilage aggregates that resulted in mass mortality episodes of macrozoobenthic species. During the 2000-2013 period, an oligotrophication of the northern Adriatic formed the basis for the recovery of Cystoseira taxa, whose abundances from 2009 to 2013 were similar to those characterising the most flourishing Mediterranean Cystoseira assemblages.

  12. Long-term fluctuations in Cystoseira populations along the west Istrian Coast (Croatia) related to eutrophication patterns in the northern Adriatic Sea.

    PubMed

    Iveša, Ljiljana; Djakovac, Tamara; Devescovi, Massimo

    2016-05-15

    An exploration of historical data suggested that eutrophication patterns might drive long-term fluctuations in Cystoseira populations along the west Istrian Coast (northern Adriatic Sea, Croatia). The regimes of northern Italian rivers, which flow approximately 100km west of the study area, mainly modulate the eutrophication levels of the northern Adriatic Sea. A regression of Cystoseira populations from the 1970s through the 1990s corresponded to increased levels of eutrophication in the study area. During the late 1990s, the density of sea urchins, which are efficacious macroalgal predators, decreased, likely due to an intense formation of pelagic mucilage aggregates that resulted in mass mortality episodes of macrozoobenthic species. During the 2000-2013 period, an oligotrophication of the northern Adriatic formed the basis for the recovery of Cystoseira taxa, whose abundances from 2009 to 2013 were similar to those characterising the most flourishing Mediterranean Cystoseira assemblages. PMID:26975612

  13. Molecular evolution of Azagny virus, a newfound hantavirus harbored by the West African pygmy shrew (Crocidura obscurior) in Côte d'Ivoire

    PubMed Central

    2011-01-01

    Background Tanganya virus (TGNV), the only shrew-associated hantavirus reported to date from sub-Saharan Africa, is harbored by the Therese's shrew (Crocidura theresae), and is phylogenetically distinct from Thottapalayam virus (TPMV) in the Asian house shrew (Suncus murinus) and Imjin virus (MJNV) in the Ussuri white-toothed shrew (Crocidura lasiura). The existence of myriad soricid-borne hantaviruses in Eurasia and North America would predict the presence of additional hantaviruses in sub-Saharan Africa, where multiple shrew lineages have evolved and diversified. Methods Lung tissues, collected in RNAlater®, from 39 Buettikofer's shrews (Crocidura buettikoferi), 5 Jouvenet's shrews (Crocidura jouvenetae), 9 West African pygmy shrews (Crocidura obscurior) and 21 African giant shrews (Crocidura olivieri) captured in Côte d'Ivoire during 2009, were systematically examined for hantavirus RNA by RT-PCR. Results A genetically distinct hantavirus, designated Azagny virus (AZGV), was detected in the West African pygmy shrew. Phylogenetic analysis of the S, M and L segments, using maximum-likelihood and Bayesian methods, under the GTR+I+Γ model of evolution, showed that AZGV shared a common ancestry with TGNV and was more closely related to hantaviruses harbored by soricine shrews than to TPMV and MJNV. That is, AZGV in the West African pygmy shrew, like TGNV in the Therese's shrew, did not form a monophyletic group with TPMV and MJNV, which were deeply divergent and basal to other rodent- and soricomorph-borne hantaviruses. Ancestral distributions of each hantavirus lineage, reconstructed using Mesquite 2.74, suggested that the common ancestor of all hantaviruses was most likely of Eurasian, not African, origin. Conclusions Genome-wide analysis of many more hantaviruses from sub-Saharan Africa are required to better understand how the biogeographic origin and radiation of African shrews might have contributed to, or have resulted from, the evolution of hantaviruses

  14. Solar quiet day ionospheric source current in the West African region

    NASA Astrophysics Data System (ADS)

    Obiekezie, Theresa N.; Okeke, Francisca N.

    2013-05-01

    The Solar Quiet (Sq) day source current were calculated using the magnetic data obtained from a chain of 10 magnetotelluric stations installed in the African sector during the French participation in the International Equatorial Electrojet Year (IEEY) experiment in Africa. The components of geomagnetic field recorded at the stations from January-December in 1993 during the experiment were separated into the source and (induced) components of Sq using Spherical Harmonics Analysis (SHA) method. The range of the source current was calculated and this enabled the viewing of a full year's change in the source current system of Sq.

  15. Solar quiet day ionospheric source current in the West African region.

    PubMed

    Obiekezie, Theresa N; Okeke, Francisca N

    2013-05-01

    The Solar Quiet (Sq) day source current were calculated using the magnetic data obtained from a chain of 10 magnetotelluric stations installed in the African sector during the French participation in the International Equatorial Electrojet Year (IEEY) experiment in Africa. The components of geomagnetic field recorded at the stations from January-December in 1993 during the experiment were separated into the source and (induced) components of Sq using Spherical Harmonics Analysis (SHA) method. The range of the source current was calculated and this enabled the viewing of a full year's change in the source current system of Sq. PMID:25685434

  16. Seasonal and regional variability in dissolved and particulate iron fluxes via glacial runoff along the West Greenland coast

    NASA Astrophysics Data System (ADS)

    Choquette, K.; Hagedorn, B.; Sletten, R. S.; Harrold, Z.; Liu, L.; Dieser, M.; Cameron, K. A.; Christner, B. C.; Junge, K.

    2012-12-01

    Subglacial weathering, due to biogeochemical and physical weathering processes, can affect the chemical evolution of subglacial waters and release dissolved and particulate iron via glacial runoff. Iron is a growth limiting nutrient and plays a critical role in the biogeochemical cycles of coastal and marine waters. More recently, dissolved and colloidal iron derived from subglacial sources have been considered an important contributor of Fe fluxes to the ocean; however, their dependency on lithology, grain size, and microbial activity is not well understood. This study characterizes the solute chemistry, in particular iron mineralogy and dissolved iron concentrations, released from beneath the Greenland Ice Sheet (GrIS), from two locations along the West Greenland coast, Thule (76°N, 68°W) and Kangerlussuaq (67°N, 50°W). We hypothesize that the subglacial lithology has a control on Fe fluxes from the GrIS to coastal and marine systems. The underlying bedrock in Thule is the Precambrian Dundas and Narssarssuk sedimentary formations which include sandstone, siltstone, and shale. The bedrock in Kangerlussuaq is dominated by Archean granodioritic gneiss and amphibolite within the Nagssugtoqidian Orogen. Supra and subglacial meltwater samples were collected directly in front of the Ice Sheet over an entire melt season in 2011 (North River, Thule) and 2012 (Akuliarusiarsuup Kuua River, Kangerlussuaq). In situ parameters such as temperature, pH, dissolved oxygen, and electrical conductivity were recorded in order to interpret meltwater chemistry. Dissolved Fe(II) and Fe(III) species were fixed immediately and analyzed within 24 hours after sampling in the field laboratory using a spectrophotometer and 10 cm cell. Total dissolved iron (FeT) of different size fractions (<0.22 and <0.05 μm) of iron were determined back in the home laboratory using reaction cell ICP MS. Preliminary results demonstrate that subglacial meltwater of North River has average Fe

  17. Effectiveness of loess in rejuvenating soil and ecosystem properties in a high leaching environment, West Coast, New Zealand

    NASA Astrophysics Data System (ADS)

    Eger, A.; Almond, P. C.; Condron, L. M.

    2010-12-01

    In the absence of major disturbances, humid terrestrial ecosystems tend over long time scales towards deficiency of biogeochemically accessible nutrients. This phenomenon has been implicated in ecosystem retrogression. Aeolian deposition has been shown to be an important mitigating effect on nutrient depletion in soils and ecosystems of old landsurfaces (e.g. Hawaii, Amazon Basin). Significant nutrient loss has been demonstrated on surfaces as young as Holocene age in very high leaching environments (>2,000 mm/a) and ecosystem retrogression has been reported for landsurfaces formed ca. 100 ka. The aim of this study is to quantify the capacity of actively accumulating loess to replenish nutrient pools in soils and ecosystems in a super-humid, temperate environment on the west coast of the South Island, New Zealand. The study area, a sequence of Holocene dune ridges under a conifer (podocarp) rainforest, combines a loess flux gradient downwind of a braided riverbed on a 6,500 y old dune ridge and, distal from the loess source, an adjacent chronosequence of dune ridges (170-6,500 y BP age range). Pedogenesis is very rapid with Spodosols developing after 1,000 y under a thick organic root mat. Our approach is based on the principle that if loess deposition has rejuvenating effects on soils or ecosystems, then it will result in soils or ecosystems of a given age having properties consistent with those on a younger, less leached landsurface. How much younger determines the strength of the rejuvenating effect. We sampled and analysed soils, to a depth of 1 m by standard methods to determine total profile masses of important macro nutrients, conducted a vegetation survey and sampled tree foliage of fully expanded, fresh leaves of sunlit branches. Along the loess gradient, foliar nutrient P concentrations in two main canopy species increased according to a power law towards the river, corresponding to an inverse logarithmic increase in loess flux rate from 0 at 1,000 m

  18. Isolation and characterization of a nodavirus associated with mass mortality in Asian seabass (Lates calcarifer) from the west coast of India.

    PubMed

    Banerjee, Debashis; Hamod, Mohammed A; Suresh, Thangavel; Karunasagar, Indrani

    2014-12-01

    A fish nodavirus was detected in the juveniles of Asian seabass (Lates calcarifer) during a massive outbreak in the seabass cage culture farm located in the south west coast of India. The clinical signs of the disease included anorexia, inflated abdomen, exophthalmia, darkening of the whole body, erratic swimming and cork-screw type movement followed by death. The dead and the moribund fish were analyzed for nodavirus by reverse transcriptase-polymerase chain reaction (RT-PCR) using specific primers targeting the T4 region of RNA2 coat protein gene. This is the first report of nodavirus infection in the fresh water cage-reared seabass fish in the west coast of India. The piscine nodavirus was detected in the brain, retina and kidney of all the fishes examined. The PCR products were cloned and sequenced. The sequence analysis showed more than 90 % homology with the other coat protein gene sequence of piscine nodaviruses from other countries. The phylogenetic analysis based on the partial nucleotide sequence of RNA2 coat protein gene revealed that the virus belonged to the red-spotted grouper nervous necrosis virus, which is one of the widely distributed genotype among the other four known genotypes of piscine nodavirus. PMID:25674617

  19. Wave energy converter with enhanced amplitude response at frequencies coinciding with Swedish west coast sea states by use of a supplementary submerged body

    NASA Astrophysics Data System (ADS)

    Engström, J.; Eriksson, M.; Isberg, J.; Leijon, M.

    2009-09-01

    The full-scale direct-driven wave energy converter developed at Uppsala University has been in offshore operation at the Swedish west coast since 2006. Earlier simulations have now been validated by full-scale experiment with good agreement. Based on that, a theoretical model for a passive system having optimum amplitude response at frequencies coinciding with Swedish west coast conditions has been developed. The amplitude response is increased by adding supplementary inertia by use of the additional mass from a submerged body. A sphere with neutral buoyancy is chosen as the submerged body and modeled as being below the motion of the waves. The model is based on potential linear wave theory and the power capture ratio is studied for real ocean wave data collected at the research test site. It is found that the power capture ratio for the two body system can be increased from 30% to 60% compared to a single body system. Increased velocity in the system also decreases the value for optimal load damping from the generator, opening up the possibility to design smaller units.

  20. Distribution and abundance of zooplankton in relation to petroleum hydrocarbon content along the coast of Kollam (Quilon), south west coast of India.

    PubMed

    Sharma, B S; Cyril, Wilma

    2007-01-01

    In the present study we examine status, impact and trends in prevailing situation of coastal ecosystem of Chavara, Neendakara, Tangasseri and Paravur zones of Kollam coast in terms of zooplankton density and petroleum hydrocarbon content (PHC). Zooplankton samples and water samples were collected during the period May 2003 to June 2004. The numerical count of zooplankton made and PHC content estimated. Paravur offshore recorded the maximum zooplankton count (1390 no./m3) and Tangasseri nearshore the lowest (700.5 no/m3). The petroleum hydrocarbon content was highest at Tangasseri nearshore (21.95 microg/l) and lowest at Paravur offshore (9.40 microg/l). We also observe statistically significant negative correlation between zooplankton density and PHC for a few organisms. The overall impact appears minor, yet, coastal ocean monitoring imperative for sustainable development. PMID:17717986