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Sample records for central sahara threat

  1. Unravelling biodiversity, evolution and threats to conservation in the Sahara-Sahel.

    Science.gov (United States)

    Brito, José C; Godinho, Raquel; Martínez-Freiría, Fernando; Pleguezuelos, Juan M; Rebelo, Hugo; Santos, Xavier; Vale, Cândida G; Velo-Antón, Guillermo; Boratyński, Zbyszek; Carvalho, Sílvia B; Ferreira, Sónia; Gonçalves, Duarte V; Silva, Teresa L; Tarroso, Pedro; Campos, João C; Leite, João V; Nogueira, Joana; Alvares, Francisco; Sillero, Neftalí; Sow, Andack S; Fahd, Soumia; Crochet, Pierre-André; Carranza, Salvador

    2014-02-01

    Deserts and arid regions are generally perceived as bare and rather homogeneous areas of low diversity. The Sahara is the largest warm desert in the world and together with the arid Sahel displays high topographical and climatic heterogeneity, and has experienced recent and strong climatic oscillations that have greatly shifted biodiversity distribution and community composition. The large size, remoteness and long-term political instability of the Sahara-Sahel, have limited knowledge on its biodiversity. However, over the last decade, there have been an increasing number of published scientific studies based on modern geomatic and molecular tools, and broad sampling of taxa of these regions. This review tracks trends in knowledge about biodiversity patterns, processes and threats across the Sahara-Sahel, and anticipates needs for biodiversity research and conservation. Recent studies are changing completely the perception of regional biodiversity patterns. Instead of relatively low species diversity with distribution covering most of the region, studies now suggest a high rate of endemism and larger number of species, with much narrower and fragmented ranges, frequently limited to micro-hotspots of biodiversity. Molecular-based studies are also unravelling cryptic diversity associated with mountains, which together with recent distribution atlases, allows identifying integrative biogeographic patterns in biodiversity distribution. Mapping of multivariate environmental variation (at 1 km × 1 km resolution) of the region illustrates main biogeographical features of the Sahara-Sahel and supports recently hypothesised dispersal corridors and refugia. Micro-scale water-features present mostly in mountains have been associated with local biodiversity hotspots. However, the distribution of available data on vertebrates highlights current knowledge gaps that still apply to a large proportion of the Sahara-Sahel. Current research is providing insights into key

  2. Holocene palaeoenvironmental changes in the central Sahara (NE-Niger)

    Science.gov (United States)

    Brauneck, J.; Baumhauer, R.

    2009-04-01

    Although a high number of investigations focussed on the succession of climatological conditions in the Central Sahara, some uncertainties still exist as some of the results show discontinuities and mostly are of low temporal and spatial resolution. Two expeditions in 2005 and 2006 headed to the northeastern parts of Niger to investigate the known remains of palaeolakes and search some new and undetected ones. The sediments found at several sites were investigated in order to receive a complete picture of the Late Quaternary environmental settings and to produce high-resolution proxies for palaeoclimate modelling. The most valuable and best-investigated study site is the sebkha of Seggedim, where a core of 15 meters length could be extracted which revealed a composition of high-resolution sections. Stratigraphical, structural and geochemical investigations as well as the analysis of thin sections allow the characterisation of different environmental conditions throughout the core. Most importantly, a complex age-depth model could be constructed, based on 21 accelerator mass spectrometry (AMS) radiocarbon measurements and reaching from Early to Mid Holocene. Driven by climate and hydrogeological influence, the water body developed from a water pond of several metres depth within a stable, grass and shrub vegetated landscape, to a freshwater lake in a more dynamic environmental setting. Radiocarbon dates set the beginning of the stage at about 10.6 ka cal BP, with an exceptionally stable regime to 6.6 ka cal BP (at 12.6 metres' depth), when a major change in the sedimentation regime of the basin is recorded in the core. Increased erosion, likely due to decreased vegetation cover within the basin, led to the filling of the lake within a few hundred years and the subsequent development of a sebkha due to massive evaporation. Due to the lack of dateable material in the upper core section, the termination of the lake stage and the onset of the subsequent sebkha stage

  3. Notes on Old Stone Constructions of West and Central Sahara

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    Mark MILBURN

    2009-10-01

    Full Text Available RESUMEN: El presente trabajo trata acerca de la tumba de TIN-HUMAN, HOGGAR, y la describe presentándola en relacón con los «monumentos en capilla» de Négrine, Tafilalet y Oeste del Sahara. Además, incluye comentarios sobre la rareza de las tumbas rectangulares con habitaciones interiores. Se hace una razonable exposición de los «monumentos fusiformes», conectados con la tradición del tránsito por barco a la vida futura. La tumba de TIN-HINAN combina características de los monumentos en capilla o habitación con aquellas otras de «monumentos de deambulatorio complejo».ABSTRACT: This work deals with the tomb of Tin-Hinan, Hoggar, and describes it as presenting a relationship with the «monuments à chapelle» of Négrine, Tafilalet and West Sahara which also have very large chambers. It also includes a commentarity on the rarity of rectangular tombs with interior chambers. It proposes a reasonable explanation of the «fusiformes monuments» as being connected with a tradition of a journey by ship to the after-life (this being suggested by their very shape. The tomb of Tin-Hinan combines characteristics of the «monument à chapelle ou à chambre» with those of a «monument à déambulatoire complexe».

  4. Pre-Islamic Dry-Stone Monuments of the Central and Western Sahara

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    Gauthier, Yves

    Saharan dry-stone monuments are important cultural markers: not only do they highlight the boundaries of the areas occupied by different prehistoric populations, but they also reveal information about the rites and beliefs of Holocene Saharan populations. As climate deteriorated in the Middle Holocene, ways of life changed, with indirect impacts on the architecture of the monuments and on the way they were oriented. Tens of thousands of recorded monuments, of various types, allow us to understand what the orientation rules were and how they changed with location. Data compiled for the eleven types of monuments reveal that many monuments of the central Sahara and Tibesti were probably aligned toward the rising sun or moon, that three types of the Atlantic Sahara show instead a random distribution, and that monuments with a pan-Saharan distribution have a complex orientation pattern. A correlation or orientation with key landscape features is likely for three monument types, coexisting with criteria based on lunisolar alignment.

  5. Inside the "African cattle complex": animal burials in the holocene central Sahara.

    Science.gov (United States)

    di Lernia, Savino; Tafuri, Mary Anne; Gallinaro, Marina; Alhaique, Francesca; Balasse, Marie; Cavorsi, Lucia; Fullagar, Paul D; Mercuri, Anna Maria; Monaco, Andrea; Perego, Alessandro; Zerboni, Andrea

    2013-01-01

    Cattle pastoralism is an important trait of African cultures. Ethnographic studies describe the central role played by domestic cattle within many societies, highlighting its social and ideological value well beyond its mere function as 'walking larder'. Historical depth of this African legacy has been repeatedly assessed in an archaeological perspective, mostly emphasizing a continental vision. Nevertheless, in-depth site-specific studies, with a few exceptions, are lacking. Despite the long tradition of a multi-disciplinary approach to the analysis of pastoral systems in Africa, rarely do early and middle Holocene archaeological contexts feature in the same area the combination of settlement, ceremonial and rock art features so as to be multi-dimensionally explored: the Messak plateau in the Libyan central Sahara represents an outstanding exception. Known for its rich Pleistocene occupation and abundant Holocene rock art, the region, through our research, has also shown to preserve the material evidence of a complex ritual dated to the Middle Pastoral (6080-5120 BP or 5200-3800 BC). This was centred on the frequent deposition in stone monuments of disarticulated animal remains, mostly cattle. Animal burials are known also from other African contexts, but regional extent of the phenomenon, state of preservation of monuments, and associated rock art make the Messak case unique. GIS analysis, excavation data, radiocarbon dating, zooarchaeological and isotopic (Sr, C, O) analyses of animal remains, and botanical information are used to explore this highly formalized ritual and the lifeways of a pastoral community in the Holocene Sahara.

  6. Oil in the Sahara: mapping anthropogenic threats to Saharan biodiversity from space.

    Science.gov (United States)

    Duncan, Clare; Kretz, Daniela; Wegmann, Martin; Rabeil, Thomas; Pettorelli, Nathalie

    2014-01-01

    Deserts are among the most poorly monitored and understood biomes in the world, with evidence suggesting that their biodiversity is declining fast. Oil exploration and exploitation can constitute an important threat to fragmented and remnant desert biodiversity, yet little is known about where and how intensively such developments are taking place. This lack of information hinders local efforts to adequately buffer and protect desert wildlife against encroachment from anthropogenic activity. Here, we investigate the use of freely available satellite imagery for the detection of features associated with oil exploration in the African Sahelo-Saharan region. We demonstrate how texture analyses combined with Landsat data can be employed to detect ground-validated exploration sites in Algeria and Niger. Our results show that site detection via supervised image classification and prediction is generally accurate. One surprising outcome of our analyses is the relatively high level of site omission errors in Niger (43%), which appears to be due to non-detection of potentially small-scale, temporary exploration activity: we believe the repeated implementation of our framework could reduce the severity of potential methodological limitations. Overall, our study provides a methodological basis for the mapping of anthropogenic threats associated with oil exploitation that can be conducted across desert regions.

  7. Inside the "African cattle complex": animal burials in the holocene central Sahara.

    Directory of Open Access Journals (Sweden)

    Savino di Lernia

    Full Text Available Cattle pastoralism is an important trait of African cultures. Ethnographic studies describe the central role played by domestic cattle within many societies, highlighting its social and ideological value well beyond its mere function as 'walking larder'. Historical depth of this African legacy has been repeatedly assessed in an archaeological perspective, mostly emphasizing a continental vision. Nevertheless, in-depth site-specific studies, with a few exceptions, are lacking. Despite the long tradition of a multi-disciplinary approach to the analysis of pastoral systems in Africa, rarely do early and middle Holocene archaeological contexts feature in the same area the combination of settlement, ceremonial and rock art features so as to be multi-dimensionally explored: the Messak plateau in the Libyan central Sahara represents an outstanding exception. Known for its rich Pleistocene occupation and abundant Holocene rock art, the region, through our research, has also shown to preserve the material evidence of a complex ritual dated to the Middle Pastoral (6080-5120 BP or 5200-3800 BC. This was centred on the frequent deposition in stone monuments of disarticulated animal remains, mostly cattle. Animal burials are known also from other African contexts, but regional extent of the phenomenon, state of preservation of monuments, and associated rock art make the Messak case unique. GIS analysis, excavation data, radiocarbon dating, zooarchaeological and isotopic (Sr, C, O analyses of animal remains, and botanical information are used to explore this highly formalized ritual and the lifeways of a pastoral community in the Holocene Sahara.

  8. Crater palaeolakes in the Tibesti mountains (Central Sahara, North Chad) - New insights into past Saharan climates

    Science.gov (United States)

    Kröpelin, Stefan; Dinies, Michèle; Sylvestre, Florence; Hoelzmann, Philipp

    2016-04-01

    For the first time continuous lacustrine sections were sampled from the volcanic Tibesti Mountains (Chad): In the 900 m deep crater of Trou au Natron at Pic Toussidé (3,315 m a.s.l.) and from the 800 m deep Era Kohor, the major sub-caldera of Emi Koussi (3,445 m a.s.l.). The remnant diatomites on their slopes are located 360 m (Trou au Natron) and 125 m (Era Kohor) above the present day bottom of the calderas. These sediments from highly continental positions in the central Sahara are keys for the reconstruction of the last climatic cycles (Kröpelin et al. 2015). We report first results from sedimentary-geochemical (total organic and total inorganic carbon contents; total nitrogen; major elements; mineralogy) and palynological analyses for palaeo-environmental interpretations. The diatomites from the Trou au Natron comprise 330 cm of mostly calcitic sediments with relatively low organic carbon (fern stands. Regional pollen rain-e.g. grasses and wormwood-is scarcely represented. Golden algae dominate in the lower section. The results of the first palynological samples suggest a small sedimentation basin. Two 14C-dated charcoals out of the upper part of the section indicate mid-Holocene ages and a linear extrapolation based on a sediment accumulation rate of 1.4mma-1 would lead to tentative dates of ~8650 cal a BP for basal lacustrine sediments and ~4450 cal a BP for the cessation of this lacustrine sequence. The diatomites from the Era Kohor reflect a suite of sections that in total sum up to 145 cm of mostly silica-based sediments with very low carbon contents (< 2% TC). Calcite dominated sediments are only present in the topmost 15 cm. Grasses and wormword are dominating throughout the sequence, probably reflecting the main constituents of the regional vegetation. Cattail (Typha/Sparganium) and especially milfoil (Myriophyllum) are recorded abundantly and continuously throughout the sequence. In combination with green algae like Pediastrum the first pollen

  9. Aerosol direct radiative forcing during Sahara dust intrusions in the Central Mediterranean

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    M. R. Perrone

    2010-08-01

    Full Text Available The clear-sky, instantaneous Direct Radiative Effect (DRE by all and anthropogenic particles is calculated during Sahara dust intrusions in the Mediterranean basin, to evaluate the role of anthropogenic particle's radiative effects and to obtain a better estimate of the DRE by desert dust. The clear-sky aerosol DRE is calculated by a two stream radiative transfer model in the solar (0.3–4 μm and infrared (4–200 μm spectral range, at the top of the atmosphere (ToA and at the Earth's surface (sfc. Aerosol optical properties by AERONET sun-sky photometer measurements and aerosol vertical profiles by EARLINET lidar measurements, both performed at Lecce (40.33° N, 18.10° E during Sahara dust intrusions occurred from 2003 to 2006 year, are used to perform radiative transfer simulations. Instantaneous values at 0.44 μm of the real (n and imaginary (k refractive index and of the of aerosol optical depth (AOD vary within the 1.33–1.55, 0.0037–0.014, and 0.2–0.7 range, respectively during the analyzed dust outbreaks. Fine mode particles contribute from 34% to 85% to the AOD by all particles. The complex atmospheric chemistry of the Mediterranean basin that is also influenced by regional and long-range transported emissions from continental Europe and the dependence of dust optical properties on soil properties of source regions and transport pathways, are responsible for the high variability of n, k, and AOD values and of the fine mode particle contribution. Instantaneous all-wave (solar+infrared DREs that are negative as a consequence of the cooling effect by aerosol particles, span the – (32–10 Wm−2 and the – (44–20 Wm−2 range at the ToA and surface, respectively. The instantaneous all-wave DRE by anthropogenic particles that is negative, varies within – (13–7 Wm−2 and – (18–11 Wm−2 at the ToA and surface, respectively. It represents from 41

  10. Aerosol direct radiative forcing during Sahara dust intrusions in the central Mediterranean

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    M. R. Perrone

    2009-10-01

    Full Text Available The clear-sky, instantaneous Direct Radiative Effect (DRE by all and anthropogenic particles is calculated during Sahara dust intrusions in the Mediterranean basin, to evaluate the role of anthropogenic particle's radiative effects and to get a better estimate of the DRE by desert dust. The clear-sky aerosol DRE is calculated by a two stream radiative transfer model in the solar (0.3–4 μm and infrared (4–200 μm spectral range, at the top of the atmosphere (ToA and at the Earth's surface (sfc. Aerosol optical properties by AERONET sun-sky photometer measurements and aerosol vertical profiles by EARLINET lidar measurements, both performed at Lecce (40.33° N, 18.10° E during Sahara dust intrusions occurred from 2003 to 2006 year, are used to initialize radiative transfer simulations. Instantaneous values at 0.44 μm of the real (n and imaginary (k refractive index and of the of aerosol optical depth (AOD vary within the 1.33–1.55, 0.0037–0.014, and 0.2–0.7 range, respectively during the analyzed dust outbreaks. Fine mode particles contribute from 34% to 85% to the AOD by all particles. The complex atmospheric chemistry of the Mediterranean basin that is also influenced by regional and long-range transported emissions from continental Europe and the dependence of dust optical properties on soil properties of source regions and transport pathways are responsible for the high variability of n, k, and AOD values and of the fine mode particle contribution. Instantaneous net (solar+infrared DREs that are negative as a consequence of the cooling effect by aerosol particles, span the – (32–10 W m−2 and the – (44–20 W m−2 range at the ToA and surface, respectively. The instantaneous net DRE by anthropogenic particles that is negative, varies within −(13–8 W m−2 and −(17–11 W m−2 at the ToA and surface, respectively. It represents from 41 up to 89

  11. Late Quaternary palaeoenvironmental information inferred from terrestrial archives in the central Sahara

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    Brauneck, J.; Baumhauer, R.

    2009-04-01

    Reconnaissance surveys in northeastern Niger since 1977 have revealed, from such evidence as diatomite-lined depressions, the existence of palaeolakes there. Initial research has shown that the palaeolimnic sediments and palaeosoils found are suitable for reconstructing its Late Quaternary palaeoenvironment. The most valuable and best-investigated study site is the sebkha of Seggedim, where a core of 15 meters length could be extracted which revealed a composition of high-resolution sections. Stratigraphical, structural and geochemical investigations as well as the analysis of thin sections allow the characterisation of different environmental conditions throughout the core. Most importantly, a complex age-depth model could be constructed, based on 21 accelerator mass spectrometry (AMS) radiocarbon measurements and reaching from Early to Mid Holocene. The results obtained from the core are compared with those from terrestrial and lacustrine sediments from outside the depression, situated a few hundred kilometres further to the north. Within the plateau landscape of Djado, Mangueni and Tchigai, two depressions and a valley containing lacustrine deposits, were investigated for palaeoenvironmental reconstruction. Depending on modifying local factors, these sediment archives were of shorter existence than the lake, but reveal additional information about the landscape dynamics from Early to Mid Holocene. The few perennial lacustrine climate archives still active to present day within the Sahara reveal apparently unique characteristics, as the local conditions that led to their existence are indeed exceptional. The interpretation of such a standalone location has to be performed with caution, as it inhibits several sources of error. The Seggedim depression may be considered such a unique spot at least for a limited time. The information obtained from the initial and freshwater lake sediments showed no noticeable signs of climatic alterations until Mid Holocene

  12. Takarkori rock shelter (SW Libya): an archive of Holocene climate and environmental changes in the central Sahara

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    Cremaschi, Mauro; Zerboni, Andrea; Mercuri, Anna Maria; Olmi, Linda; Biagetti, Stefano; di Lernia, Savino

    2014-10-01

    Rock shelters in the central Saharan massifs preserve anthropogenic stratigraphic sequences that represent both a precious archive for the prehistory of the region and a powerful proxy data for Holocene palaeoenvironments. The geoarchaeological (micromorphology) and archaeobotanical (pollen analysis) approaches were integrated to investigate the anthropogenic sedimentary sequence preserved within the Takarkori rock shelter, a Holocene archaeological site located in the Libyan central Sahara (southern Tadrart Acacus massif). The site was occupied throughout the Early and Middle Holocene (African Humid Period) by groups of hunter-gatherers before and by pastoral communities later. The investigation on the inner part of the sequence allows to recognize the anthropogenic contribution to sedimentation process, and to reconstruct the major changes in the Holocene climate. At the bottom of the stratigraphic sequence, evidence for the earliest frequentation of the site by hunters and gatherers has been recognized; it is dated to c. 10,170 cal yr BP and is characterized by high availability of water, freshwater habitats and sparsely wooded savannah vegetation. A second Early Holocene occupation ended at c. 8180 cal yr BP; this phase is marked by increased aridity: sediments progressively richer in organics, testifying to a more intense occupation of the site, and pollen spectra indicating a decrease of grassland and the spreading of cattails, which followed a general lowering of lake level or widening of shallow-water marginal habitats near the site. After this period, a new occupational phase is dated between c. 8180 and 5610 cal yr BP; this period saw the beginning of the frequentation of pastoral groups and is marked by an important change in the forming processes of the sequence. Sediments and pollen spectra confirm a new increase in water availability, which led to a change in the landscape surrounding the Takarkori rock shelter with the spreading of water bodies. The

  13. Intraseasonal variability and atmospheric controls on daily dust occurrence frequency over the central and western Sahara during the boreal summer

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    Ashpole, Ian; Washington, Richard

    2013-12-01

    classify satellite-derived maps of daily dust occurrence frequency over the central and western Sahara (CWS) during the boreal summer in order to identify typical patterns using the neural network based system of self-organized maps. Resulting dust states vary in terms of the frequency of dust occurrence and its location. The most commonly occurring dust states are those of relatively low dust detection frequency. On days with relatively high dust occurrence, dust tends to favor either a location close to the Algeria-Mali-Niger border triple point (TP) or further to the northwest across the western half of the Mali-Algeria border (MAB). States in which dust is detected at both locations simultaneously are rare. There is a distinct intraseasonal progression in preferred dust location from the TP in the early season to the MAB later in the season. The evolution of dust states reveals a one-way transition from dust at the TP to dust at the MAB and then to reduced daily dust occurrence frequency. There is a distinct degree of interannual variability in the occurrence frequency of the different states, dominated by the extremes of high and low dust detection frequency. Analysis of climatological composites demonstrates that monsoon surges into the Saharan heat low are associated with days of high dust detection frequency, while a strong Harmattan into the CWS is linked to days with less frequent dust presence. The CWS atmospheric dust budget for June-August is thus strongly linked to the dynamics of the West African monsoon.

  14. Drug Trafficking as a Lethal Regional Threat in Central America

    Science.gov (United States)

    2011-12-16

    and Central America are only found in some magazines like TIME, and “Nueva Sociedad ” [New Society]. Another good source for analysis of current...relacion compleja” [Drugs and Insecurity in Latin America: a complex relation] published by the Colombian magazine Nueva Sociedad in July-August 2000...Organization of American States. 65 Table 1. Police Ratios in Central America Source: Author Interviews; Observatoriapara la violencia , Honduras; CIA

  15. The daytime cycle in dust aerosol direct radiative effects observed in the central Sahara during the Fennec campaign in June 2011

    KAUST Repository

    Banks, Jamie R.

    2014-12-16

    © 2014. American Geophysical Union. All Rights Reserved. The direct clear-sky radiative effect (DRE) of atmospheric mineral dust is diagnosed over the Bordj Badji Mokhtar (BBM) supersite in the central Sahara during the Fennec campaign in June 2011. During this period, thick dust events were observed, with aerosol optical depth values peaking at 3.5. Satellite observations from Meteosat-9 are combined with ground-based radiative flux measurements to obtain estimates of DRE at the surface, top-of-atmosphere (TOA), and within the atmosphere. At TOA, there is a distinct daytime cycle in net DRE. Both shortwave (SW) and longwave (LW) DRE peak around noon and induce a warming of the Earth-atmosphere system. Toward dusk and dawn, the LW DRE reduces while the SW effect can switch sign triggering net radiative cooling. The net TOA DRE mean values range from -9 Wm-2 in the morning to heating of +59 Wm-2 near midday. At the surface, the SW dust impact is larger than at TOA: SW scattering and absorption by dust results in a mean surface radiative cooling of 145Wm-2. The corresponding mean surface heating caused by increased downward LW emission from the dust layer is a factor of 6 smaller. The dust impact on the magnitude and variability of the atmospheric radiative divergence is dominated by the SW cooling of the surface, modified by the smaller SW and LW effects at TOA. Consequently, dust has a mean daytime net radiative warming effect on the atmosphere of 153Wm-2.

  16. Ammonoids from the Dalle des Iridet of the Mouydir and Ahnet (Central Sahara and the Formation d'Hassi Sguilma of the Saoura Valley (Late Tournaisian–Early Viséan; Algeria

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    D. Korn

    2010-02-01

    Full Text Available Four ammonoid species are described from the Early Carboniferous (Mississippian Iridet Formation of the Ahnet and Mouydir (Central Sahara, Algeria; three of which are new: Eurites temertassetensis n. sp., Trimorphoceras teguentourense n. sp., and Trimorphoceras azzelmattiense n. sp. The species can be attributed to the North African Ammonellipsites-Merocanites Assemblage (Fascipericyclus-Ammonellipsites Genus Zone; Late Tournaisian to Early Viséan. Additionally, the two new species Ammonellipsites sguilmensis n. sp. and Muensteroceras beniabbesense n. sp. are described from the time equivalent Hassi Sguilma Formation of the Saoura Valley (north-western Algeria. doi:10.1002/mmng.200900012

  17. NON-TRADITIONAL SECURITY THREATS IN CENTRAL ASIA REGIONAL PERSPECTIVE OF COMPARATIVE PERSPECTIVE

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    Ramakant Trivedi

    2011-01-01

    Full Text Available Abstract: The article explores the roots and current state of religious extremism in Central Asia, as well as investigates its connections with the global salafi movement. It evaluates attempts of the regional players and external stakeholders to address the existing threats, and provides recommendations for their advancement.

  18. Sahara en mouvement

    OpenAIRE

    Casajus, Dominique

    2013-01-01

    On peut dire du Sahara ce que Fernand Braudel disait naguère de la Méditerranée : lui assigner des bornages est une tâche malaisée. Des géographes s’y sont cependant essayés, et leurs tentatives participent de ce qu’on peut appeler l’« invention » du Sahara. La présente introduction évoque quelques figures marquantes de cette invention (Léon l’Africain, Eugène Daumas, Émile Carette, Henri Duveyrier, Robert Capot-Rey…) puis présente brièvement les diverses contributions du dossier, en les repl...

  19. [Malaria in Algerian Sahara].

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    Hammadi, D; Boubidi, S C; Chaib, S E; Saber, A; Khechache, Y; Gasmi, M; Harrat, Z

    2009-08-01

    Thanks to the malaria eradication campaign launched in Algeria in 1968, the number of malaria cases fell down significantly from 95,424 cases in 1960 to 30 cases in 1978. At that time the northern part of the country was declared free of Plasmodium falciparum. Only few cases belonging to P. vivax persisted in residual foci in the middle part of the country. In the beginning of the eighties, the south of the country was marked by an increase of imported malaria cases. The resurgence of the disease in the oases coincided with the opening of the Trans-Saharan road and the booming trade with the neighbouring southern countries. Several authors insisted on the risk of introduction of malaria or its exotic potential vectors in Algeria via this new road. Now, the totality of malaria autochthonous cases in Algeria are located in the south of the country where 300 cases were declared during the period (1980-2007). The recent outbreak recorded in 2007 at the borders with Mall and the introduction of Anopheles gambiae into the Algerian territory show the vulnerability of this area to malaria which is probably emphasized by the local environmental changes. The authors assess the evolution of malaria in the Sahara region and draw up the distribution of the anopheles in this area.

  20. Game Theoretic Evaluation of Threat Detection Problems-The Central Role of the Adversary

    Energy Technology Data Exchange (ETDEWEB)

    Heasler, Patrick G.; Wood, Thomas W.; Reichmuth, Barbara A.

    2007-01-01

    A wide variety of security problems hinge on the detection of threats and discrimination of threats from innocuous objects. The theory that frames these problems is common among medical diagnostics, radar and sonar imaging, and detection of radiological, chemical, and biological agents. In many of these problems, the nature of the threat is subject to control by a malicious adversary, and the choice of a reference (or "design basis") threat is a very diffcult, and often intractable, aspect of the problem. It is this class of problems that this report considers.

  1. Comment on "Climate-driven ecosystem succession in the Sahara: the past 6000 years".

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    Brovkin, Victor; Claussen, Martin

    2008-11-28

    Kröpelin et al. (Research Articles, 9 May 2008, p. 765) interpreted a sediment record from Lake Yoa in the east-central part of North Africa as support for a weak biogeophysical climate-vegetation feedback in the Sahara during the mid-Holocene. We argue that the new data do not invalidate earlier modeling results on strong land-atmosphere coupling in the Western Sahara for which the Lake Yoa record is far less representative.

  2. Former Military Networks a Threat to Peace? The Demobilisation and Remobilization of Renamo in Central Mozambique

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    Nikkie Wiegink

    2015-11-01

    Full Text Available Renamo’s recent upsurge against the Mozambican Frelimo-led government after 22 years of relative stability has challenged the country’s often celebrated disarmament, demobilization and reintegration process (1992 to 1994. Drawing on ethnographic fieldwork conducted in Maringue (Sofala province, the location of the rebels’ wartime headquarters and a post-war Renamo stronghold, this paper shows that while the DDR program supposedly ended Renamo’s command and control structure, the former rebel network continued to be a central feature of ex-combatants’ social worlds. Former Renamo combatants spend most of their time in the company of their ‘colleagues of the trenches’ and engaged in relationships of dependency with political Renamo leaders and former commanders. These relationships were not only shaped by the former military structure, but also by friendship, marriage, and patronage dynamics, providing ex-Renamo combatants with physical and economic safety, a sense of belonging and economic possibilities. Recent events in Mozambique suggest that the post-conflict continuation of informal wartime networks is a threat to peace and a failure of demobilization. Nevertheless, the fieldwork conducted in Maringue reveals that the dismantling of the command and control structure is often in vain, as it may be worthwhile for ex-combatants to maintain ties with their former military group for various reasons. Therefore, I argue that it may be useful to consider these networks based on the former armed group in processes of violence reduction, also in the development of DDR programs, as these may offer possibilities for the re-positioning and transformation of (former armed actors.

  3. Breve historia de Radio Sahara

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    Montes Fernández, Francisco José

    2013-01-01

    Full Text Available La historia de Radio Sahara es uno de los períodos menos estudiado en nuestra bibliografía, lo cual tampoco es sintomático sino una muestra más de lo mucho que hay que investigar sobre la historia reciente denuestro país, especialmente en el terreno de la radiodifusión. He profundizado en todo lo que he podido, pero es indudable que queda mucho camino por recorrer. Aquí hay pistas y datos todos verdaderos sobre una parte importante, pero no lo doy por finalizado sino que aspiro a que sirva de aliciente para que futuros investigadores continúen con el camino iniciado. Se trata de describir lo que fue la historia de esta emisora

  4. Cretaceous Crocodyliforms from the Sahara

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    Paul Sereno

    2009-11-01

    Full Text Available Diverse crocodyliforms have been discovered in recent years in Cretaceous rocks on southern landmasses formerly composing Gondwana.  We report here on six species from the Sahara with an array of trophic adaptations that significantly deepen our current understanding of African crocodyliform diversity during the Cretaceous period.  We describe two of these species (Anatosuchus minor, Araripesuchus wegeneri from nearly complete skulls and partial articulated skeletons from the Lower Cretaceous Elrhaz Formation (Aptian-Albian of Niger. The remaining four species (Araripesuchus rattoides sp. n., Kaprosuchus saharicus gen. n. sp. n., Laganosuchus thaumastos gen. n. sp. n., Laganosuchus maghrebensis gen. n. sp. n. come from contemporaneous Upper Cretaceous formations (Cenomanian in Niger and Morocco.

  5. Highways and outposts: economic development and health threats in the central Brazilian Amazon region

    Directory of Open Access Journals (Sweden)

    Damacena Giseli N

    2010-06-01

    Full Text Available Abstract Background Economic development is often evoked as a driving force that has the capacity to improve the social and health conditions of remote areas. However, development projects produce uneven impacts on local communities, according to their different positions within society. This study examines the spatial distribution of three major health threats in the Brazilian Amazon region that may undergo changes through highway construction. Homicide mortality, AIDS incidence and malaria prevalence rates were calculated for 70 municipalities located within the areas of influence of the Cuiabá-Santarém highway (BR-163, i.e. in the western part of the state of Pará state and the northern part of Mato Grosso. Results The municipalities were characterized using social and economic indicators such as gross domestic product (GDP, urban and indigenous populations, and recent migration. The municipalities' connections to the region's main transportation routes (BR-163 and Trans-Amazonian highways, along with the Amazon and Tapajós rivers were identified by tagging the municipalities that have boundaries crossing these routes, using GIS overlay operations. Multiple regression was used to identify the major driving forces and constraints relating to the distribution of health threats. The main explanatory variables for higher malaria prevalence were: proximity to the Trans-Amazonian highway, high proportion of indigenous population and low proportion of migrants. High homicide rates were associated with high proportions of migrants, while connection to the Amazon River played a protective role. AIDS incidence was higher in municipalities with recent increases in GDP and high proportions of urban population. Conclusions Highways induce social and environmental changes and play different roles in spreading and maintaining diseases and health threats. The most remote areas are still protected against violence but are vulnerable to malaria. Rapid

  6. Modulation of instrumental responding by a conditioned threat stimulus requires lateral and central amygdala

    Directory of Open Access Journals (Sweden)

    Vincent eCampese

    2015-10-01

    Full Text Available Two studies explored the role of the amygdala in response modulation by an aversive conditioned stimulus (CS in rats. Experiment 1 investigated the role of amygdala circuitry in conditioned suppression using a paradigm in which licking for sucrose was inhibited by a tone CS that had been previously paired with footshock. Electrolytic lesions of the lateral amygdala impaired suppression relative to sham-operated animals, and produced the same pattern of results when applied to central amygdala. In addition, disconnection of the lateral and central amygdala, by unilateral lesion of each on opposite sides of the brain, also impaired suppression relative to control subjects that received lesions of both areas on the same side. In each case, lesions were placed following Pavlovian conditioning and instrumental training, but before testing. This procedure produced within-subjects measures of the effects of lesion on freezing and between-group comparisons for the effects on suppression. Experiment 2 extended this analysis to a task where an aversive CS suppressed shuttling responses that had been previously food reinforced and also found effects of bilateral lesions of the central amygdala in a pre-post design. Together, these studies demonstrate that connections between the lateral and central amygdala constitute a serial circuit involved in processing aversive Pavlovian stimuli, and add to a growing body of findings implicating central amygdala in the modulation of instrumental behavior.

  7. Rainfall regimes of the Green Sahara.

    Science.gov (United States)

    Tierney, Jessica E; Pausata, Francesco S R; deMenocal, Peter B

    2017-01-01

    During the "Green Sahara" period (11,000 to 5000 years before the present), the Sahara desert received high amounts of rainfall, supporting diverse vegetation, permanent lakes, and human populations. Our knowledge of rainfall rates and the spatiotemporal extent of wet conditions has suffered from a lack of continuous sedimentary records. We present a quantitative reconstruction of western Saharan precipitation derived from leaf wax isotopes in marine sediments. Our data indicate that the Green Sahara extended to 31°N and likely ended abruptly. We find evidence for a prolonged "pause" in Green Sahara conditions 8000 years ago, coincident with a temporary abandonment of occupational sites by Neolithic humans. The rainfall rates inferred from our data are best explained by strong vegetation and dust feedbacks; without these mechanisms, climate models systematically fail to reproduce the Green Sahara. This study suggests that accurate simulations of future climate change in the Sahara and Sahel will require improvements in our ability to simulate vegetation and dust feedbacks.

  8. Using Flow Regime Lightning and Sounding Climatologies to Initialize Gridded Lightning Threat Forecasts for East Central Florida

    Science.gov (United States)

    Lambert, Winifred; Short, David; Volkmer, Matthew; Sharp, David; Spratt, Scott

    2007-01-01

    Each morning, the forecasters at the National Weather Service in Melbourne, FL (NWS MLB) produce an experimental cloud-to-ground (CG) lightning threat index map for their county warning area (CWA) that is posted to their web site (httl://www.srh.weather.gov/mlb/ghwo/lightning.shtml) . Given the hazardous nature of lightning in East Central Florida, especially during the warm season months of May September, these maps help users factor the threat of lightning, relative to their location, into their daily plans. The maps are color-coded in five levels from Very Low to Extreme, with threat level definitions based on the probability of lightning occurrence and the expected amount of CG activity. On a day in which thunderstorms are expected, there are typically two or more threat levels depicted spatially across the CWA. The locations of relative lightning threat maxima and minima often depend on the position and orientation of the low-level ridge axis, forecast propagation and interaction of sea/lake/outflow boundaries, expected evolution of moisture and stability fields, and other factors that can influence the spatial distribution of thunderstorms over the CWA. The lightning threat index maps are issued for the 24-hour period beginning at 1200 UTC each day with a grid resolution of 5 km x 5 km. Product preparation is performed on the AWIPS Graphical Forecast Editor (GFE), which is the standard NWS platform for graphical editing. Until recently, the forecasters created each map manually, starting with a blank map. To improve efficiency of the forecast process, NWS MLB requested that the Applied Meteorology Unit (AMU) create gridded warm season lightning climatologies that could be used as first-guess inputs to initialize lightning threat index maps. The gridded values requested included CG strike densities and frequency of occurrence stratified by synoptic-scale flow regime. The intent was to improve consistency between forecasters while allowing them to focus on the

  9. Health effects from Sahara dust episodes in Europe: literature review and research gaps.

    Science.gov (United States)

    Karanasiou, A; Moreno, N; Moreno, T; Viana, M; de Leeuw, F; Querol, X

    2012-10-15

    The adverse consequences of particulate matter (PM) on human health have been well documented. Recently, special attention has been given to mineral dust particles, which may be a serious health threat. The main global source of atmospheric mineral dust is the Sahara desert, which produces about half of the annual mineral dust. Sahara dust transport can lead to PM levels that substantially exceed the established limit values. A review was undertaken using the ISI web of knowledge database with the objective to identify all studies presenting results on the potential health impact from Sahara dust particles. The review of the literature shows that the association of fine particles, PM₂.₅, with total or cause-specific daily mortality is not significant during Saharan dust intrusions. However, regarding coarser fractions PM₁₀ and PM₂.₅₋₁₀ an explicit answer cannot be given. Some of the published studies state that they increase mortality during Sahara dust days while other studies find no association between mortality and PM₁₀ or PM₂.₅₋₁₀. The main conclusion of this review is that health impact of Saharan dust outbreaks needs to be further explored. Considering the diverse outcomes for PM₁₀ and PM₂.₅₋₁₀, future studies should focus on the chemical characterization and potential toxicity of coarse particles transported from Sahara desert mixed or not with anthropogenic pollutants. The results of this review may be considered to establish the objectives and strategies of a new European directive on ambient air quality. An implication for public policy in Europe is that to protect public health, anthropogenic sources of particulate pollution need to be more rigorously controlled in areas highly impacted by the Sahara dust.

  10. Quantification of anthropogenic threats to lakes in a lowland county of central Sweden.

    Science.gov (United States)

    Brunberg, A K; Blomqvist, P

    2001-05-01

    An evaluation of the negative effects caused by anthropogenic influence on lake ecosystems was performed, using data from 143 catchments in Uppsala County, Sweden. The study included i) technical encroachments; i.e. construction of dams, dikes, etc. as well as effects of drainage of land; ii) pollution, i.e. eutrophication, acidification, and contamination by toxic substances; iii) introduction of nonnative species; and iv) exploitation of species populations. Severe damage was caused mostly by drainage of land followed by pollution by toxic substances and, to a smaller extent, introduction of nonnative species and eutrophication. Most lakes were subject to several types of disturbances, interacting in a complex pattern, which made it difficult to link the visible effects to the true causes of the disturbance. Future lake management should include analyses of all disturbances to the lake catchments, taking into account the historical perspective, in order to balance the threats/damages, in an analysis of the possibilities for maintaining biodiversity and sustainability in the ecosystems.

  11. Zika virus in Gabon (Central Africa--2007: a new threat from Aedes albopictus?

    Directory of Open Access Journals (Sweden)

    Gilda Grard

    2014-02-01

    Full Text Available Chikungunya and dengue viruses emerged in Gabon in 2007, with large outbreaks primarily affecting the capital Libreville and several northern towns. Both viruses subsequently spread to the south-east of the country, with new outbreaks occurring in 2010. The mosquito species Aedes albopictus, that was known as a secondary vector for both viruses, recently invaded the country and was the primary vector involved in the Gabonese outbreaks. We conducted a retrospective study of human sera and mosquitoes collected in Gabon from 2007 to 2010, in order to identify other circulating arboviruses.Sample collections, including 4312 sera from patients presenting with painful febrile disease, and 4665 mosquitoes belonging to 9 species, split into 247 pools (including 137 pools of Aedes albopictus, were screened with molecular biology methods. Five human sera and two Aedes albopictus pools, all sampled in an urban setting during the 2007 outbreak, were positive for the flavivirus Zika (ZIKV. The ratio of Aedes albopictus pools positive for ZIKV was similar to that positive for dengue virus during the concomitant dengue outbreak suggesting similar mosquito infection rates and, presumably, underlying a human ZIKV outbreak. ZIKV sequences from the envelope and NS3 genes were amplified from a human serum sample. Phylogenetic analysis placed the Gabonese ZIKV at a basal position in the African lineage, pointing to ancestral genetic diversification and spread.We provide the first direct evidence of human ZIKV infections in Gabon, and its first occurrence in the Asian tiger mosquito, Aedes albopictus. These data reveal an unusual natural life cycle for this virus, occurring in an urban environment, and potentially representing a new emerging threat due to this novel association with a highly invasive vector whose geographic range is still expanding across the globe.

  12. Sleep Deprivation Impairs the Human Central and Peripheral Nervous System Discrimination of Social Threat.

    Science.gov (United States)

    Goldstein-Piekarski, Andrea N; Greer, Stephanie M; Saletin, Jared M; Walker, Matthew P

    2015-07-15

    Facial expressions represent one of the most salient cues in our environment. They communicate the affective state and intent of an individual and, if interpreted correctly, adaptively influence the behavior of others in return. Processing of such affective stimuli is known to require reciprocal signaling between central viscerosensory brain regions and peripheral-autonomic body systems, culminating in accurate emotion discrimination. Despite emerging links between sleep and affective regulation, the impact of sleep loss on the discrimination of complex social emotions within and between the CNS and PNS remains unknown. Here, we demonstrate in humans that sleep deprivation impairs both viscerosensory brain (anterior insula, anterior cingulate cortex, amygdala) and autonomic-cardiac discrimination of threatening from affiliative facial cues. Moreover, sleep deprivation significantly degrades the normally reciprocal associations between these central and peripheral emotion-signaling systems, most prominent at the level of cardiac-amygdala coupling. In addition, REM sleep physiology across the sleep-rested night significantly predicts the next-day success of emotional discrimination within this viscerosensory network across individuals, suggesting a role for REM sleep in affective brain recalibration. Together, these findings establish that sleep deprivation compromises the faithful signaling of, and the "embodied" reciprocity between, viscerosensory brain and peripheral autonomic body processing of complex social signals. Such impairments hold ecological relevance in professional contexts in which the need for accurate interpretation of social cues is paramount yet insufficient sleep is pervasive.

  13. Using Cloud-to-Ground Lightning Climatologies to Initialize Gridded Lightning Threat Forecasts for East Central Florida

    Science.gov (United States)

    Lambert, Winnie; Sharp, David; Spratt, Scott; Volkmer, Matthew

    2005-01-01

    Each morning, the forecasters at the National Weather Service in Melbourn, FL (NWS MLB) produce an experimental cloud-to-ground (CG) lightning threat index map for their county warning area (CWA) that is posted to their web site (http://www.srh.weather.gov/mlb/ghwo/lightning.shtml) . Given the hazardous nature of lightning in central Florida, especially during the warm season months of May-September, these maps help users factor the threat of lightning, relative to their location, into their daily plans. The maps are color-coded in five levels from Very Low to Extreme, with threat level definitions based on the probability of lightning occurrence and the expected amount of CG activity. On a day in which thunderstorms are expected, there are typically two or more threat levels depicted spatially across the CWA. The locations of relative lightning threat maxima and minima often depend on the position and orientation of the low-level ridge axis, forecast propagation and interaction of sea/lake/outflow boundaries, expected evolution of moisture and stability fields, and other factors that can influence the spatial distribution of thunderstorms over the CWA. The lightning threat index maps are issued for the 24-hour period beginning at 1200 UTC (0700 AM EST) each day with a grid resolution of 5 km x 5 km. Product preparation is performed on the AWIPS Graphical Forecast Editor (GFE), which is the standard NWS platform for graphical editing. Currently, the forecasters create each map manually, starting with a blank map. To improve efficiency of the forecast process, NWS MLB requested that the Applied Meteorology Unit (AMU) create gridded warm season lightning climatologies that could be used as first-guess inputs to initialize lightning threat index maps. The gridded values requested included CG strike densities and frequency of occurrence stratified by synoptic-scale flow regime. The intent is to increase consistency between forecasters while enabling them to focus on

  14. Rainfall regimes of the Green Sahara

    Science.gov (United States)

    Tierney, Jessica E.; Pausata, Francesco S. R.; deMenocal, Peter B.

    2017-01-01

    During the “Green Sahara” period (11,000 to 5000 years before the present), the Sahara desert received high amounts of rainfall, supporting diverse vegetation, permanent lakes, and human populations. Our knowledge of rainfall rates and the spatiotemporal extent of wet conditions has suffered from a lack of continuous sedimentary records. We present a quantitative reconstruction of western Saharan precipitation derived from leaf wax isotopes in marine sediments. Our data indicate that the Green Sahara extended to 31°N and likely ended abruptly. We find evidence for a prolonged “pause” in Green Sahara conditions 8000 years ago, coincident with a temporary abandonment of occupational sites by Neolithic humans. The rainfall rates inferred from our data are best explained by strong vegetation and dust feedbacks; without these mechanisms, climate models systematically fail to reproduce the Green Sahara. This study suggests that accurate simulations of future climate change in the Sahara and Sahel will require improvements in our ability to simulate vegetation and dust feedbacks. PMID:28116352

  15. Solar hydrogen: the Great Sahara project

    Energy Technology Data Exchange (ETDEWEB)

    Eljrushi, G.S. (High Industrial Inst., Misurata (Libyan Arab Jamahiriya)); Zubia, J.N. (Secretariat of Light Industry, Misurata (Libyan Arab Jamahiriya))

    1994-03-01

    This paper discusses a proposal for an international solar hydrogen project to be installed in North Africa, near the town of Ghadames in the middle of the desert, to exploit the enormous Sahara solar power resource. It suggests some practical steps to implement this project in three successive stages. The financing of the project is discussed, and the relevant local activities have been outlined. It also discusses the forming of a task force from interested parties to take initiatives and to present facts about the benefits that would result from harnessing the Sahara's limitless reservoir of solar energy. (author)

  16. Cenozoic stratigraphy of the Sahara, Northern Africa

    Science.gov (United States)

    Swezey, Christopher S.

    2009-01-01

    This paper presents an overview of the Cenozoic stratigraphic record in the Sahara, and shows that the strata display some remarkably similar characteristics across much of the region. In fact, some lithologies of certain ages are exceptionally widespread and persistent, and many of the changes from one lithology to another appear to have been relatively synchronous across the Sahara. The general stratigraphic succession is that of a transition from early Cenozoic carbonate strata to late Cenozoic siliciclastic strata. This transition in lithology coincides with a long-term eustatic fall in sea level since the middle Cretaceous and with a global climate transition from a Late Cretaceous–Early Eocene “warm mode” to a Late Eocene–Quaternary “cool mode”. Much of the shorter-term stratigraphic variability in the Sahara (and even the regional unconformities) also can be correlated with specific changes in sea level, climate, and tectonic activity during the Cenozoic. Specifically, Paleocene and Eocene carbonate strata and phosphate are suggestive of a warm and humid climate, whereas latest Eocene evaporitic strata (and an end-Eocene regional unconformity) are correlated with a eustatic fall in sea level, the build-up of ice in Antarctica, and the appearance of relatively arid climates in the Sahara. The absence of Oligocene strata throughout much of the Sahara is attributed to the effects of generally low eustatic sea level during the Oligocene and tectonic uplift in certain areas during the Late Eocene and Oligocene. Miocene sandstone and conglomerate are attributed to the effects of continued tectonic uplift around the Sahara, generally low eustatic sea level, and enough rainfall to support the development of extensive fluvial systems. Middle–Upper Miocene carbonate strata accumulated in northern Libya in response to a eustatic rise in sea level, whereas Upper Miocene mudstone accumulated along the south side of the Atlas Mountains because uplift of the

  17. Emerging viral threats in Gabon: health capacities and response to the risk of emerging zoonotic diseases in Central Africa.

    Science.gov (United States)

    Bourgarel, M; Wauquier, N; Gonzalez, J-P

    2010-01-01

    Emerging infectious diseases (EID) are currently the major threat to public health worldwide and most EID events have involved zoonotic infectious agents. Central Africa in general and Gabon in particular are privileged areas for the emergence of zoonotic EIDs. Indeed, human incursions in Gabonese forests for exploitation purposes lead to intensified contacts between humans and wildlife thus generating an increased risk of emergence of zoonotic diseases. In Gabon, 51 endemic or potential endemic viral infectious diseases have been reported. Among them, 22 are of zoonotic origin and involve 12 families of viruses. The most notorious are dengue, yellow fever, ebola, marburg, Rift Valley fever and chikungunya viruses. Potential EID due to wildlife in Gabon are thereby plentiful and need to be inventoried. The Gabonese Public Health system covers geographically most of the country allowing a good access to sanitary information and efficient monitoring of emerging diseases. However, access to treatment and prevention is better in urban areas where medical structures are more developed and financial means are concentrated even though the population is equally distributed between urban and rural areas. In spite of this, Gabon could be a good field for investigating the emergence or re-emergence of zoonotic EID. Indeed Gabonese health research structures such as CIRMF, advantageously located, offer high quality researchers and facilities that study pathogens and wildlife ecology, aiming toward a better understanding of the contact and transmission mechanisms of new pathogens from wildlife to human, the emergence of zoonotic EID and the breaking of species barriers by pathogens.

  18. Sahara: Barrier or corridor? Nonmetric cranial traits and biological affinities of North African late Holocene populations.

    Science.gov (United States)

    Nikita, Efthymia; Mattingly, David; Lahr, Marta Mirazón

    2012-02-01

    The Garamantes flourished in southwestern Libya, in the core of the Sahara Desert ~3,000 years ago and largely controlled trans-Saharan trade. Their biological affinities to other North African populations, including the Egyptian, Algerian, Tunisian and Sudanese, roughly contemporary to them, are examined by means of cranial nonmetric traits using the Mean Measure of Divergence and Mahalanobis D(2) distance. The aim is to shed light on the extent to which the Sahara Desert inhibited extensive population movements and gene flow. Our results show that the Garamantes possess distant affinities to their neighbors. This relationship may be due to the Central Sahara forming a barrier among groups, despite the archaeological evidence for extended networks of contact. The role of the Sahara as a barrier is further corroborated by the significant correlation between the Mahalanobis D(2) distance and geographic distance between the Garamantes and the other populations under study. In contrast, no clear pattern was observed when all North African populations were examined, indicating that there was no uniform gene flow in the region.

  19. Adsorption of dyes on Sahara desert sand.

    Science.gov (United States)

    Varlikli, Canan; Bekiari, Vlasoula; Kus, Mahmut; Boduroglu, Numan; Oner, Ilker; Lianos, Panagiotis; Lyberatos, Gerasimos; Icli, Siddik

    2009-10-15

    Sahara desert sand (SaDeS) was employed as a mineral sorbent for retaining organic dyes from aqueous solutions. Natural sand has demonstrated a strong affinity for organic dyes but significantly lost its adsorption capacity when it was washed with water. Therefore, characterization of both natural and water washed sand was performed by XRD, BET, SEM and FTIR techniques. It was found that water-soluble kyanite, which is detected in natural sand, is the dominant factor affecting adsorbance of cationic dyes. The sand adsorbs over 75% of cationic dyes but less than 21% for anionic ones. Among the dyes studied, Methylene Blue (MB) demonstrated the strongest affinity for Sahara desert sand (Q(e)=11.98 mg/g, for initial dye solution concentration 3.5 x 10(-5)mol/L). The effects of initial dye concentration, the amount of the adsorbent, the temperature and the pH of the solution on adsorption capacity were tested by using Methylene Blue as model dye. Pseudo-first-order, pseudo-second-order and intraparticle diffusion models were applied. It was concluded that adsorption of Methylene Blue on Sahara desert sand followed pseudo-second order kinetics. Gibbs free energy, enthalpy change and entropy change were calculated and found -6411 J/mol, -30360 J/mol and -76.58 J/mol K, respectively. These values indicate that the adsorption is an exothermic process and has a spontaneous nature at low temperatures.

  20. Three million years of monsoon variability over the northern Sahara

    Energy Technology Data Exchange (ETDEWEB)

    Larrasoana, J.C.; Roberts, A.P.; Rohling, E.J.; Winklhofer, M. [School of Ocean and Earth Science, Southampton Oceanography Centre, University of Southampton, European Way, Southampton SO14 3ZH (United Kingdom); Wehausen, R. [Institut fuer Chemie und Biologie des Meeres (ICBM), Carl-von-Ossietzky-Universitaet, 26111, Oldenburg (Germany)

    2003-12-01

    We present a 3 million year record of aeolian dust supply into the eastern Mediterranean Sea, based on hematite contents derived from magnetic properties of sediments from Ocean Drilling Program Site 967. Our record has an average temporal resolution of {proportional_to}400 years. Geochemical data validate this record of hematite content as a proxy for the supply of aeolian dust from the Sahara. We deduce that the aeolian hematite in eastern Mediterranean sediments derives from the eastern Algerian, Libyan, and western Egyptian lowlands located north of the central Saharan watershed ({proportional_to}21 N). In corroboration of earlier work, we relate dust flux minima to penetration of the African summer monsoon front to the north of the central Saharan watershed. This would have enhanced soil humidity and vegetation cover in the source regions, in agreement with results from ''green Sahara'' climate models. Our results indicate that this northward monsoon penetration recurred during insolation maxima throughout the last 3 million years. As would be expected, this orbital precession-scale mechanism is modulated on both short ({proportional_to}100-kyr) and long ({proportional_to}400-kyr) eccentricity time scales. We also observe a strong expression of the {proportional_to}41-kyr (obliquity) cycle, which we discuss in terms of high- and low-latitude mechanisms that involve Southern Hemisphere meridional temperature contrasts and shifts in the latitudes of the tropics, respectively. We also observe a marked increase in sub-Milankovitch variability around the mid-Pleistocene transition ({proportional_to}0.95 Ma), which suggests a link between millennial-scale climate variability, including monsoon dynamics, and the size of northern hemisphere ice sheets. (orig.)

  1. Development of the Peace Process in the Western Sahara Conflict

    Science.gov (United States)

    2014-06-13

    DEVELOPMENT OF THE PEACE PROCESS IN THE WESTERN SAHARA CONFLICT A thesis presented to the Faculty of the U.S. Army Command...AND SUBTITLE Development of the Peace Process in the Western Sahara Conflict 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PRO GRAM ELEMENT...Spain in 1884, The Western Sahara has been a theater of dispute between different actors in different times. Spain relinquished the administration of

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

    Science.gov (United States)

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

    2009-12-01

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

  3. Eghindi among Sahrawi refugees of Western Sahara.

    Science.gov (United States)

    Volpato, Gabriele; Waldstein, Anna

    2014-01-01

    Eghindi is an illness built around a set of pathological states experienced by Sahrawi in the desert environment of Western Sahara. Its core symptoms are caused by osmotic imbalances related to salt consumption. In 1975, many Sahrawi were exiled into refugee camps, and they have since experienced radical sociocultural changes, which are reflected in changing explanatory models of eghindi. Older and conservative refugees, attached to traditional Sahrawi culture, have expanded its conceptualization to include new pathogenic factors, while younger and progressive refugees, acculturated with Western culture, began challenging its existence. Eghindi became embodied within a broader process of negotiation of Sahrawi cultural identity. Our findings provide a framework for thinking about the evolution of illness in response to displacement, and highlight that when explanatory models evolve, intracultural tensions can arise within a population.

  4. Rare wetland grass Coleanthus subtilis in Central and Western Europe – current distribution, habitat types, and threats

    Directory of Open Access Journals (Sweden)

    Elke Richert

    2016-09-01

    Full Text Available The moss grass Coleanthus subtilis (Tratt. Seidl is a rare, diminutive grass which grows on wet muddy bottoms of drained water bodies displaying a high degree of water level dynamics, such as fishponds or water reservoirs. Due to the temporal character of its habitat, C. subtilis has a very short life cycle of only a few weeks. Therefore, the species and its habitats are legally protected on both national and international levels. This paper focuses on habitats and the conservation of C. subtilis in Central and Western Europe. For the period of 2000–2013, the Czech Republic with more than 200 sites represents the main distribution area of this species in Central and Western Europe. During the same period, C. subtilis was recorded from 45 sites in three regions of Germany (33 Lusatia, 11 Ore Mountains, 1 Mid-Elbe River, 16 sites in France, 13 sites in Poland, and four sites in Austria. Since 2000, the number of records within these seven regions seems to have followed different trends: whereas two regions (Lusatia, Germany and southern Poland became newly colonized and many populations established, in one region (Ore Mountains, Germany the number of records diminished. Owing to its specific life cycle, both reproduction success and maintenance of C. subtilis populations are closely linked to the prevailing water level regime, mainly dependent on the management of the water body. Management for the conservation of C. subtilis populations should consider the entire complex of water bodies, as well as individual ponds. For the preservation of the species, at least one pond in each complex should be drained every year and each pond should be drained at least once within 5 years. Depending on local climatic conditions, ponds should be drained for 8–10 weeks during the time period from mid-March to mid-November.

  5. Effect of heat treatment on antimycotic activity of Sahara honey

    Institute of Scientific and Technical Information of China (English)

    Moussa Ahmed; Saad Aissat; Noureddine Djebli

    2014-01-01

    Objective: To evaluate the influence of the temperature on honey colour, polyphenol contents and antimycotic capacity and to evaluate the correlation between these parameters. Methods:Sahara honey were heated up to 25, 50, 75 and 100 °C for 15, 30 and 60 min, and their colour intensity, polyphenol contents and antimycotic capacity. The Folin-Ciocalteu test was used to determine the total polyphenol contents (TPC). The antimycotic activity was evaluated both by agar diffusion method and micro wells dilution method against the Candida albicans (C. albicans) and Candida glabrata (C. glabrata). Results:Initial values for TPC in Sahara honey ranged from 0.55 to 1.14 mg of gallic acid per kg of honey, with the average value of 0.78 mg of gallic acid per kg of honey. The TPC values after heat-treatment were 0.54 to 1.54 with the average value of 1.49 mg. The minimal inhibitory concentrations before heat-treatment of Sahara honey against C. albicans and C. glabrata ranged from 3.06%-12.5% and 50% respectively. After heat-treatment the minimal inhibitory concentrations between 12.5% and 50% for C. albicans and C. glabrata, respectively. The diameters of inhibition zones of Sahara honey with 50% concentration varied from (12.67-15.00) mm by C. albicans to (14.33-15.67) mm by C. glabrata. The diameters of inhibition zones after heat-treatment at 25 and 50 °C for 15.30 and 60 min ranged from (2.00-18.67) mm by C. albicans to (8.00-16.67) mm by C. glabrata. Statistically significant relations between the TPC and the colour intensity of Sahara honey (r=0.99, P Conclusions:To our knowledge this is the first report on the antimycotic capacity of Sahara honey.

  6. Alternative energies. Sahara Power needs pan-European grid operator

    Energy Technology Data Exchange (ETDEWEB)

    Van Wijland, G.

    2009-09-15

    A consortium of leading European - mostly German - companies plans to invest 400 billion euros in a megaproject to generate solar power in the Sahara desert. Desertec, as the project is called, could cover 15 percent of European electricity demand. The problem is, how do you transport this power to Paris and Berlin? It can only work with a pan-European grid operator.

  7. Modeling non-monotone risk aversion using SAHARA utility functions

    NARCIS (Netherlands)

    A. Chen; A. Pelsser; M. Vellekoop

    2011-01-01

    We develop a new class of utility functions, SAHARA utility, with the distinguishing feature that it allows absolute risk aversion to be non-monotone and implements the assumption that agents may become less risk averse for very low values of wealth. The class contains the well-known exponential and

  8. Africa, Sub-Sahara: A Selected Functional and Country Bibliography.

    Science.gov (United States)

    Foreign Service (Dept. of State), Washington, DC. Foreign Service Inst.

    Sub-Sahara Africa is covered in this bibliography prepared for use in training programs. Consisting of nearly 500 citations which date from 1940 to the present, topics covered include: POPULATION, Traditional Cultures, Religion, Art, Literature, History, Colonialism, Economic Development, Agricultural Modernization, Education and Manpower,…

  9. Solar power at the edge of the Sahara desert

    Energy Technology Data Exchange (ETDEWEB)

    Bresler, Ines

    2012-07-01

    In Morocco, the turn in the energy sector is overseen by His Majesty the King himself: in 2009, the King introduced the Moroccan Solar Plan and created the Moroccan Agency for Solar Energy (MASEN) for its implementation. This year, the construction work for the first project complex will commence at the edge of the Sahara desert. (orig.)

  10. Africa South of the Sahara: A Guide to Reference Sources.

    Science.gov (United States)

    Mason, Mary, Comp.

    This annotated bibliography has been compiled as an introduction to reference resources for college-level African studies and to suggest useful tools for literature searches. It is a guide to materials in the library of McGill University. Call numbers are included. The titles cited refer to Africa South of the Sahara as a whole or to large…

  11. Cultural Astronomy in Africa South of the Sahara

    Science.gov (United States)

    Holbrook, Jarita

    This chapter examines two foci of cultural astronomy found in Africa south of the Sahara: creation myths and celestial art. The examples highlighted are from the Akan, the Bahima, the Boshongo, the Fon, the Igbo, the Mambila, the Yoruba, and the Zulu people.

  12. Frontières et nationalisme autour du Sahara Occidental (Borders and Nationalism in Western Sahara

    Directory of Open Access Journals (Sweden)

    Luis Martinez

    2011-01-01

    Full Text Available Le conflit du Sahara Occidental apparaît comme le principal facteur de blocage dans la construction d'une intégration régionale. Pour la monarchie marocaine, il lui a permis de s'approprier le sentiment nationaliste alors porté par le mouvement de l'Istiqlal qui faisait de la cause du grand Maroc l'un de ses combats politiques. Pour le régime algérien, il a représenté un moyen de justifier le pouvoir d'une armée et d'entretenir le sentiment nationaliste. L'avantage du conflit saharien était évident : l'instauration, sous couvert d'un sentiment nationaliste, de régimes politiques autoritaires. Depuis une décennie, ce conflit « gelé » est bloqué à la fois par « le statut avancé » du Maroc avec l'UE, qui n'ose aborder ce problème et le retour de l'abondance financière en Algérie qui alimente son intransigeance sur le dossier.(The conflict in Western Sahara is the main stumbling block to the construction of an integrated region. The Moroccan monarchy used the conflict to gain the support of nationalists previously allied with the Istiqlal movement whose principal political goal was the creation of a greater Morocco. The Algerian regime used the conflict as a justification for a strong military and to stir up nationalist sentiment. The advantage of the Saharan conflict was obvious: the establishment, under the guise of nationalism, of authoritarian regimes. For a decade resolution of this “frozen” conflict has been blocked by the EU’s unwillingness to address the issue in light of the “advanced status” of Morocco in the EU and by the increased intransigence of Algeria made possible by its renewed financial strength.

  13. The Green Sahara: Climate Change, Hydrologic History and Human Occupation

    Science.gov (United States)

    Blom, Ronald G.; Farr, Tom G.; Feynmann, Joan; Ruzmaikin, Alexander; Paillou, Philippe

    2009-01-01

    Archaeology can provide insight into interactions of climate change and human activities in sensitive areas such as the Sahara, to the benefit of both disciplines. Such analyses can help set bounds on climate change projections, perhaps identify elements of tipping points, and provide constraints on models. The opportunity exists to more precisely constrain the relationship of natural solar and climate interactions, improving understanding of present and future anthropogenic forcing. We are beginning to explore the relationship of human occupation of the Sahara and long-term solar irradiance variations synergetic with changes in atmospheric-ocean circulation patterns. Archaeological and climate records for the last 12 K years are gaining adequate precision to make such comparisons possible. We employ a range of climate records taken over the globe (e.g. Antarctica, Greenland, Cariaco Basin, West African Ocean cores, records from caves) to identify the timing and spatial patterns affecting Saharan climate to compare with archaeological records. We see correlation in changing ocean temperature patterns approx. contemporaneous with drying of the Sahara approx. 6K years BP. The role of radar images and other remote sensing in this work includes providing a geographically comprehensive geomorphic overview of this key area. Such coverage is becoming available from the Japanese PALSAR radar system, which can guide field work to collect archaeological and climatic data to further constrain the climate change chronology and link to models. Our initial remote sensing efforts concentrate on the Gilf Kebir area of Egypt.

  14. An Implementation Analysis of Threat Assessment Policies in Public Universities and Community Colleges in Central Texas: A Post Virginia Tech Incident Assessment

    Science.gov (United States)

    Piet DeLaTorre, Christine

    2011-01-01

    It is clear that the tragic events at Virginia Tech and other institutions of higher education (IHEs) have brought threat assessment to the forefront of higher education literature and increased public concern for campus safety. IHEs have a profound duty to learn from the Virginia Tech tragedy and to recognize their responsibility in providing a…

  15. Otters Increasing - Threats Increasing

    Directory of Open Access Journals (Sweden)

    Andreas Kranz

    1994-10-01

    Full Text Available In some parts of Central Europe populations of otters are apparently increasing. Until recently, no research was being conducted on the ecology of otters in mainly artificial habitats like fish farms. Otters are not only a new source of conflict requiring species management, but appear once again threatened by illegal hunting. Austria is dealing with this problem using compensation for otter damage, electric fencing and translocation of problem otters. Despite a rise in illegal killing, Austria does not formally recognise this as a threat.

  16. Regime shifts in the Sahara and Sahel: interactions between ecological and climatic systems in northern Africa

    NARCIS (Netherlands)

    Foley, J.A.; Coe, M.T.; Scheffer, M.; Wang, G.L.

    2003-01-01

    The Sahara and Sahel regions of northern Africa have complex environmental histories punctuated by sudden and dramatic "regime shifts" in climate and ecological conditions. Here we review the current understanding of the causes and consequences of two environmental regime shifts in the Sahara and Sa

  17. Optimal investment and indifference pricing when risk aversion is not monotone: SAHARA utility functions

    NARCIS (Netherlands)

    A. Chen; A. Pelsser; M. Vellekoop

    2008-01-01

    Abstract. We develop a new class of utility functions, SAHARA utility, with the dis- tinguishing feature that they implement the assumption that agents may become less risk-averse for very low values of wealth. This means that SAHARA utility can be used to characterize risk gambling behavior of an e

  18. Bubbling Threat

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The shift of China’s monetary policy stance from "moderately loose" to "prudent" in 2011 indicates curbing inflation and asset bubbles have become the Central Government’s top priority. But is China’s bubble problem short-term or long-term? Is it only monetary or related to economic structure? Is it the cause of China’s economic imbalance or the result? And what kind of deep-rooted problems in the macro economy does it reflect? All these questions call for deep thought,said Zhang Monan,a

  19. Sahara honey shows higher potency against Pseudomonas aeruginosa compared to north Algerian types of honey.

    Science.gov (United States)

    Boukraa, Laid; Niar, Abdellatif

    2007-12-01

    Six varieties of honey from different regions in Algeria were used to determine their potency against Pseudomonas aeruginosa. Four varieties originated from northern Algeria, and two from the Sahara. Three types of media were used. On nutrient agar the minimum inhibitory concentration (MIC) of the four northern varieties ranged between 30% (vol/vol) and 31% (vol/vol), while the MIC of the Sahara varieties was 11% (vol/vol) and 14% (vol/vol). On King A agar the MIC of the four northern varieties ranged from 25% (vol/vol) to 31% (vol/vol), whereas the MIC of the two varieties of Sahara honey was 12% (vol/vol) and 15% (vol/vol). On nutrient broth the MIC of the northern varieties ranged from 10% (vol/vol) to 21% (vol/vol), whereas the MIC of the two varieties of Sahara honey was 9% (vol/vol). The botanic flora of Sahara is known in Algeria for its medicinal uses, and thus the higher potency of the Sahara honey is most probably due to antibacterial substances in its plant derivates. These findings suggest that Sahara honey could be used for managing wounds and burns, which are mostly infected by P. aeruginosa.

  20. Cyber threat metrics.

    Energy Technology Data Exchange (ETDEWEB)

    Frye, Jason Neal; Veitch, Cynthia K.; Mateski, Mark Elliot; Michalski, John T.; Harris, James Mark; Trevino, Cassandra M.; Maruoka, Scott

    2012-03-01

    Threats are generally much easier to list than to describe, and much easier to describe than to measure. As a result, many organizations list threats. Fewer describe them in useful terms, and still fewer measure them in meaningful ways. This is particularly true in the dynamic and nebulous domain of cyber threats - a domain that tends to resist easy measurement and, in some cases, appears to defy any measurement. We believe the problem is tractable. In this report we describe threat metrics and models for characterizing threats consistently and unambiguously. The purpose of this report is to support the Operational Threat Assessment (OTA) phase of risk and vulnerability assessment. To this end, we focus on the task of characterizing cyber threats using consistent threat metrics and models. In particular, we address threat metrics and models for describing malicious cyber threats to US FCEB agencies and systems.

  1. Dry Deposition from Sahara Sources Regions of Western Africa

    Directory of Open Access Journals (Sweden)

    B. Douaiba

    2014-01-01

    Full Text Available Sahara dust storms during March 2004 have attracted much attention from the dust-research community due to their intensity, wide coverage, and endurance. In the present work, the dry deposition mechanisms of mineral dust are analysed during an event on the 3 March 2004 over the Northwest African coast. This particular case was chosen based on the strong dry removal that occurred, rendering it ideal for examining the deposition processes. The simulation of synoptic conditions and dry deposition of four dust particles including clay, small silt, large silt, and sand was performed with Eta model, coupled with a desert dust cycle module. The results have been compared with surface data from weather stations in North Africa, data of dry metals from stations located in Gran Canaria, and various satellite images such as European Organization for the Exploitation of Meteorological Satellites and Moderate Resolution Imaging Spectroradiometer for the period in question.

  2. Building Fit-for-Purpose Spatial Frameworks for Sustainable Land Governaqnce in Sub-Sahara Africa

    DEFF Research Database (Denmark)

    Enemark, Stig

    2013-01-01

    countries this countrywide spatial framework has been developed over centuries. In contrast, most developing countries have a cadastral coverage of less than 30 per cent of the country. This means that over 70 per cent of the land in many developing countries, such as the sub-Sahara region, is generally......, economic, legal, and social issues related to building such fit-for purpose spatial frameworks as a means of paving the way towards sustainable and land governance in Sub-Sahara Africa...

  3. Evidence of Laurussian affinity for parts of the Mauritanides and Souttoufides (Moroccan Sahara)

    Science.gov (United States)

    Gärtner, Andreas; Villeneuve, Michel; Linnemann, Ulf; El Archi, Abdelkrim; Bellon, Hervé

    2013-04-01

    The Soutouffide belt is located in the southern part of the Moroccan Sahara. Representing the northern section of the Carboniferous Mauritanide belt, it extends from Morocco to Senegal. The Dhlou and Adrar Souttouf Massifs, both of which belong to the Souttoufide belt, are located on the western margin of the Archean Reguibat Shield. Previously, the Adrar Souttouf Massif has been suggested to be part of the Variscan Mauritanian-Appalachian system. To date the Moroccan Sahara has been one of the least studied regions in West Africa. This study presents new zircon ages from two units of the Adrar Souttouf Massif which have nevertheless allowed us to hypothesise a complex polyphased history. The Massif can be subdivided into four NNE-SSW trending units (listed here from east to west). The Sebkha Matallah unit represents the eastern margin of the Adrar Souttouf Massif and is thrust over the Ordovician to Devonian sedimentary Dhloat Ensour Group to the east. A central (Dayet Lawda) unit consisting of mafic and ultramafic rocks is interpreted as a possible remnant of Neoproterozoic oceanic crust or mafic terranes. The western Sebkha Gezmayet and Oued Togba units are mainly composed of granitoids and orthogneisses. Zircon ages of the Tonian-Stenian (1.4-1.0 Ga) were recorded in the Oued Togba and Sebkha Gezmayet units and suggest an Avalonian-Meguman-like relationship. Three other age groups were obtained in these two units: 610 to 570 Ma (Pan-African), 530 to 490 Ma (Cambrian), and 440 to 270 Ma. The latter population cannot result from Variscan orogeny alone, and is possibly linked to the Salinic and Acadian orogenies of Laurentia. Zircon age populations at ~3.0 Ga and ~2.65 Ga determined for two granite samples from the Archean foreland are in accordance to data already published. Ages of between 226 Ma (Upper Triassic) and 158 Ma (Upper Jurassic) result from lower intercepts of discordia lines and are interpreted as a Mesozoic thermal overprint of the area attributed

  4. Threats to Bitcoin Software

    OpenAIRE

    Kateraas, Christian H

    2014-01-01

    Collect and analyse threat models to the Bitcoin ecosystem and its software. The create misuse case, attack trees, and sequence diagrams of the threats. Create a malicious client from the gathered threat models. Once the development of the client is complete, test the client and evaluate its performance. From this, assess the security of the Bitcoin software.

  5. Remote sensing of the hydrologic history of the eastern Sahara

    Science.gov (United States)

    Farr, T. G.; Blom, R. G.; Paillou, P.

    2010-12-01

    The eastern Sahara Desert has never been thoroughly mapped in terms of the landforms and subsurface signs of past climates conducive to human occupation. As part of ongoing work and through a new proposal to NASA, we are generating new maps of the paleohydrology, topography, geomorphology, and surficial deposits of the area and developing GIS-based models which use the data to pinpoint past resources and travel pathways. The maps we are generating will constitute a unique resource for exploration for water and archeological sites in the Gilf Kebir and other regions of NE Africa. That the Sahara was favorable for human habitation at times has long been known. With the remarkable paleo-landscape revealed by the L-band (25 cm) Shuttle Imaging Radar-A in 1981, it became clear that ancient humans concentrated along integrated drainage systems dubbed “radar rivers” by McCauley and colleagues. However SIR-A and subsequent long-wavelength radar coverage was limited and regional understanding of the drainage network has remained elusive. We are mapping the area with three sensors optimized for mapping and characterizing arid regions: The Japanese PALSAR L-band imaging radar, NASA’s SRTM, and ASTER. Together these sensors provide full coverage of the area allowing characterization and mapping of surface and subsurface landforms formed and modified by former wetter climates. In particular and following the work of Ghoneim, Robinson, El Baz and others, we are mapping the regional drainage network revealed by the radar images and applying modern analysis tools to the drainage basins and channels. These include drainage density, channel gradient vs. distance, and longitudinal and cross-channel topographic profiles. We use these quantities to estimate a stream’s past approach to equilibrium and this to infer balances between climate, tectonic uplift, and other changes in base level. Discovery over the last few years of large paleolakes (e.g. Mega Lake Chad, North Darfur

  6. New Instructional Materials on Africa South of the Sahara (1969-1970). A Supplement to Africa South of the Sahara: A Resource and Curriculum Guide.

    Science.gov (United States)

    Beyer, Barry K.

    This guide cites instructional materials on Africa south of the Sahara which have become available since February 1969. Acknowledging the probability of inaccuracies in the majority of the materials cited, the guide neither evaluates nor promotes items, but simply presents annotations of readings, textbooks, fact sheets, atlases, African…

  7. Low 60Fe abundance in Semarkona and Sahara 99555

    CERN Document Server

    Tang, Haolan

    2015-01-01

    Iron-60 (t1/2=2.62 Myr) is a short-lived nuclide that can help constrain the astrophysical context of solar system formation and date early solar system events. A high abundance of 60Fe (60Fe/56Fe= 4x10-7) was reported by in situ techniques in some chondrules from the LL3.00 Semarkona meteorite, which was taken as evidence that a supernova exploded in the vicinity of the birthplace of the Sun. However, our previous MC-ICPMS measurements of a wide range of meteoritic materials, including chondrules, showed that 60Fe was present in the early solar system at a much lower level (60Fe/56Fe=10-8). The reason for the discrepancy is unknown but only two Semarkona chondrules were measured by MC-ICPMS and these had Fe/Ni ratios below ~2x chondritic. Here, we show that the initial 60Fe/56Fe ratio in Semarkona chondrules with Fe/Ni ratios up to ~24x chondritic is 5.4x10-9. We also establish the initial 60Fe/56Fe ratio at the time of crystallization of the Sahara 99555 angrite, a chronological anchor, to be 1.97x10-9. The...

  8. Ancient watercourses and biogeography of the Sahara explain the peopling of the desert.

    Science.gov (United States)

    Drake, Nick A; Blench, Roger M; Armitage, Simon J; Bristow, Charlie S; White, Kevin H

    2011-01-11

    Evidence increasingly suggests that sub-Saharan Africa is at the center of human evolution and understanding routes of dispersal "out of Africa" is thus becoming increasingly important. The Sahara Desert is considered by many to be an obstacle to these dispersals and a Nile corridor route has been proposed to cross it. Here we provide evidence that the Sahara was not an effective barrier and indicate how both animals and humans populated it during past humid phases. Analysis of the zoogeography of the Sahara shows that more animals crossed via this route than used the Nile corridor. Furthermore, many of these species are aquatic. This dispersal was possible because during the Holocene humid period the region contained a series of linked lakes, rivers, and inland deltas comprising a large interlinked waterway, channeling water and animals into and across the Sahara, thus facilitating these dispersals. This system was last active in the early Holocene when many species appear to have occupied the entire Sahara. However, species that require deep water did not reach northern regions because of weak hydrological connections. Human dispersals were influenced by this distribution; Nilo-Saharan speakers hunting aquatic fauna with barbed bone points occupied the southern Sahara, while people hunting Savannah fauna with the bow and arrow spread southward. The dating of lacustrine sediments show that the "green Sahara" also existed during the last interglacial (∼125 ka) and provided green corridors that could have formed dispersal routes at a likely time for the migration of modern humans out of Africa.

  9. External threat and the definition of deviance.

    Science.gov (United States)

    Laudedale, P; Smith-Cunnien, P; Parker, J; Inverarity, J

    1984-05-01

    Research ( Lauderdale , 1976; Schachter , 1951) suggests that an external threat to a group can lead to the rejection of deviant members of the group and alteration of group communication patterns and solidarity. This study sought to extend those findings, integrate them with concepts from Simmel 's (1917/1955) work on group conflict, and link them to key issues in the societal reaction approach to deviant behavior. We examined the effect of variation in level of threat, the relationship between deviant status and nonconformity to the central task norm, the role of high-status actors in deviance designation, the relationship between rejection and negative definition of the deviant, and the effects of rejection and negative definition on group solidarity. Hypotheses were tested in an experimental design involving three conditions (strong threat, weak threat, and no threat). The results suggest that (a) the level of threat is directly related to the extent of rejection and negative definition, (b) nonconformity to the central task norm is not systematically related to deviant status, (c) high-status actors are more involved in the rejection of the deviant, (d) sociometric rejection of the deviant is accompanied by negative definition in the strong-threat condition, and (e) the level of group solidarity is related to the extent of rejection and negative definition. Implications of these findings are discussed relative to the societal reaction approach to deviant behavior and analogous processes in other social groups.

  10. Threats: power, family mealtimes, and social influence.

    Science.gov (United States)

    Hepburn, Alexa; Potter, Jonathan

    2011-03-01

    One of the most basic topics in social psychology is the way one agent influences the behaviour of another. This paper will focus on threats, which are an intensified form of attempted behavioural influence. Despite the centrality to the project of social psychology, little attention has been paid to threats. This paper will start to rectify this oversight. It reviews early examples of the way social psychology handles threats and highlights key limitations and presuppositions about the nature and role of threats. By contrast, we subject them to a programme of empirical research. Data comprise video records of a collection of family mealtimes that include preschool children. Threats are recurrent in this material. A preliminary conceptualization of features of candidate threats from this corpus will be used as an analytic start point. A series of examples are used to explicate basic features and dimensions that build the action of threatening. The basic structure of the threats uses a conditional logic: if the recipient continues problem action/does not initiate required action then negative consequences will be produced by the speaker. Further analysis clarifies how threats differ from warnings and admonishments. Sequential analysis suggests threats set up basic response options of compliance or defiance. However, recipients of threats can evade these options by, for example, reworking the unpleasant upshot specified in the threat, or producing barely minimal compliance. The implications for broader social psychological concerns are explored in a discussion of power, resistance, and asymmetry; the paper ends by reconsidering the way social influence can be studied in social psychology.

  11. Insiders and Insider Threats

    DEFF Research Database (Denmark)

    Hunker, Jeffrey; Probst, Christian W.

    2011-01-01

    Threats from the inside of an organization’s perimeters are a significant problem, since it is difficult to distinguish them from benign activity. In this overview article we discuss defining properties of insiders and insider threats. After presenting definitions of these terms, we go on to disc...... of threats, and their mitigation. Another important observation is that the distinction between insiders and outsiders seems to loose significance as IT infrastructure is used in performing insider attacks....

  12. Low 60Fe Abundance in Semarkona and Sahara 99555

    Science.gov (United States)

    Tang, Haolan; Dauphas, Nicolas

    2015-03-01

    Iron-60 (t1/2 = 2.62 Myr) is a short-lived nuclide that can help constrain the astrophysical context of Solar System formation and date early Solar System events. A high abundance of 60Fe(60Fe/56Fe ≈ 4 × 10-7) was reported by in situ techniques in some chondrules from the LL3.00 Semarkona meteorite, which was taken as evidence that a supernova exploded in the vicinity of the birthplace of the Sun. However, our previous multi-collector inductively coupled plasma mass spectrometry (MC-ICPMS) measurements of a wide range of meteoritic materials, including chondrules, showed that 60Fe was present in the early Solar System at a much lower level (60Fe/56Fe ≈ 10-8). The reason for the discrepancy is unknown but only two Semarkona chondrules were measured by MC-ICPMS and these had Fe/Ni ratios below ˜2× chondritic. Here, we show that the initial 60Fe/56Fe ratio in Semarkona chondrules with Fe/Ni ratios up to ˜24× chondritic is (5.39 ± 3.27) × 10-9. We also establish the initial 60Fe/56Fe ratio at the time of crystallization of the Sahara 99555 angrite, a chronological anchor, to be (1.97 ± 0.77) × 10-9. These results demonstrate that the initial abundance of 60Fe at Solar System birth was low, corresponding to an initial 60Fe/56Fe ratio of (1.01 ± 0.27) × 10-8.

  13. LOW {sup 60}FE ABUNDANCE IN SEMARKONA AND SAHARA 99555

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Haolan; Dauphas, Nicolas, E-mail: haolantang@ucla.edu [Origins Lab, Department of the Geophysical Sciences and Enrico Fermi Institute, The University of Chicago, 5734 South Ellis Avenue, Chicago IL 60637 (United States)

    2015-03-20

    Iron-60 (t{sub 1/2} = 2.62 Myr) is a short-lived nuclide that can help constrain the astrophysical context of Solar System formation and date early Solar System events. A high abundance of {sup 60}Fe({sup 60}Fe/{sup 56}Fe ≈ 4 × 10{sup −7}) was reported by in situ techniques in some chondrules from the LL3.00 Semarkona meteorite, which was taken as evidence that a supernova exploded in the vicinity of the birthplace of the Sun. However, our previous multi-collector inductively coupled plasma mass spectrometry (MC-ICPMS) measurements of a wide range of meteoritic materials, including chondrules, showed that {sup 60}Fe was present in the early Solar System at a much lower level ({sup 60}Fe/{sup 56}Fe ≈ 10{sup −8}). The reason for the discrepancy is unknown but only two Semarkona chondrules were measured by MC-ICPMS and these had Fe/Ni ratios below ∼2× chondritic. Here, we show that the initial {sup 60}Fe/{sup 56}Fe ratio in Semarkona chondrules with Fe/Ni ratios up to ∼24× chondritic is (5.39 ± 3.27) × 10{sup −9}. We also establish the initial {sup 60}Fe/{sup 56}Fe ratio at the time of crystallization of the Sahara 99555 angrite, a chronological anchor, to be (1.97 ± 0.77) × 10{sup −9}. These results demonstrate that the initial abundance of {sup 60}Fe at Solar System birth was low, corresponding to an initial {sup 60}Fe/{sup 56}Fe ratio of (1.01 ± 0.27) × 10{sup −8}.

  14. Teaching About Africa South of the Sahara; A Guide and Resource Packet for Ninth Grade Social Studies.

    Science.gov (United States)

    Coburn, Barbara; And Others

    This guide provides a sampling of reference materials which are pertinent for two ninth grade units: Africa South of the Sahara: Land and People, and Africa South of the Sahara: Historic Trends. The effect of urbanization upon traditional tribalistic cultures is the focus. A case study is used to encourage an inductive approach to the learning…

  15. Identifying and Mitigating Insider Threats

    DEFF Research Database (Denmark)

    Probst, Christian W.

    2011-01-01

    Organisations face many threats that coarsely can be separated in inside threats and outside threats. Threats from insiders are especially hard to counter since insiders have special knowledge and privileges. Therefore, malicious insider actions are hard to distinguish from benign actions. After...... discussing new definitions of insiders and insider threats, this article gives an overview of how to mitigate insider threats and discusses conflicting goals when dealing with insider threats....

  16. Cyber Intelligence Threat Prioritization

    Science.gov (United States)

    2014-10-01

    possible direction of their behavior. and determines their interest in targeting the organization. t Intrinsic (personally rewarding) Extrinsic (receive...actors resources. Money People Tools Training Motive Why do threat actors attack? Determining an actor’s motive provides insight into the...platform that allows anyone to make their organization more visible to threat actors. Online Presence Extracurricular Activities Motive Risk

  17. Ethnopharmacological survey and phytochemical screening of some medicinal Asteraceae from Algerian Sahara

    Directory of Open Access Journals (Sweden)

    A. CHERITI

    2013-06-01

    Full Text Available A first report of Asteraceae species census of the Algerian folk medicine, currently used in Sahara for the treatment of illenes is presented. 11 Asteraceae species namely: Anvillea radiata Coss, Artemisia herba-alba, Brocchia cinerea, Bubonium graveolens, Cotula anthemoides, Echinops spinosus, Launaea arborescens, Launaea nudicaulis, Launaea resedifolia, Scorzonera undulata and Warionia saharae were selected based on the survey through interviews with local inhabitant, herbalist in the Souk and old women according to our previous works. Ethnopharmacolgical potential and chemical constituents of this species are described.

  18. Alternative Threat Methodology

    Directory of Open Access Journals (Sweden)

    Charles B. King III

    2011-01-01

    Full Text Available Of the many challenges facing risk analysis practitioners, perhaps the most difficult to overcome is in the field of terrorist threat analysis. When estimating the threat associated with naturally occurring events, historical data provides a great deal of insight into the frequency of those events. Threat associated with accidents applies many operations research tools to gauge future failure-rates (Failure Mode and Effects Analysis being perhaps the most widely known. However, estimating the probability of an individual's or group's attacking a specific (or even a generic target is an element of risk analysis in which art and intuition are applied far more regularly than is science.

  19. Southern Africa’s Transnational Threats

    Science.gov (United States)

    2013-04-01

    smuggling of rare species and resources , money laundering, and smuggling of stolen vehicles. All of these events share a common trait. They each imply a...and Instability in Central Africa” A Threat Assesment , October 2011, linked from United Nations Office on Drugs and Crime home page at “Annual

  20. Alternate non-stop migration strategies of pied flycatchers to cross the Sahara desert

    NARCIS (Netherlands)

    Ouwehand, Janne; Both, Christiaan

    2016-01-01

    Each year more than two billion songbirds cross the Sahara, but how they perform this formidable task is largely unknown. Using geolocation tracks from 27 pied flycatchers, a nocturnally migrating passerine, we show that most birds made diurnal flights in both autumn and spring. These diurnal flight

  1. African South of the Sahara: An Objective Test for Secondary Schools. A World Regions Perception Survey.

    Science.gov (United States)

    Carnegie-Mellon Univ., Pittsburgh, PA.

    Designed by Project Africa of Carnegie-Mellon University, these two test instruments have been used to discover what selected American secondary school students know or believe about Africa and other regions of the world. The first instrument, a 30-minute objective test, "Africa South of the Sahara," is comprised of 60 multiple-choice…

  2. Abrupt shifts of the Sahara-Sahel boundary during Heinrich Stadials

    Directory of Open Access Journals (Sweden)

    J. A. Collins

    2013-01-01

    Full Text Available Relict dune fields that are found at 14° N in the modern-day African Sahel are testament to equatorward expansions of the Sahara desert during the late Pleistocene. However, difficulties of dating dune formation mean that abrupt millennial-scale climate events are not always resolved in these records. High-resolution marine core studies have identified Heinrich Stadials as the dustiest periods of the last glacial, although no studies have mapped the spatio-temporal evolution of dust export from West Africa. We use the major-element composition of four marine sediment cores to reconstruct the spatial extent of Saharan-dust versus river-sediment input to the continental margin from West Africa over the last 60 ka. This allows us to map the position of the sediment composition corresponding to the Sahara-Sahel boundary. Our records indicate that the Sahara-Sahel boundary reached its most southerly position (13° N during Heinrich Stadials, suggesting that these were the periods when the sand dunes formed at 14° N on the continent, rather than at the Last Glacial Maximum. We find that SSB position was closely linked to North Atlantic sea surface temperatures, which during Heinrich Stadials triggered abrupt increases of aridity and wind strength in the Sahel, exposing new dust sources. This result illustrates the influence of the Atlantic meridional overturning circulation on the southerly extent of the Sahara desert and has implications for global atmospheric dust loading.

  3. Africa South of the Sahara. Grade Twelve. [Resource Unit IV.] Project Social Studies.

    Science.gov (United States)

    Minnesota Univ., Minneapolis. Project Social Studies Curriculum Center.

    This is the fourth of seven resource units for a twelfth grade course on value conflicts and policy decisions. The topic for this unit is Africa south of the Sahara. The objectives are listed as to generalizations, skills, and values. The double-page format relates objectives to pertinent content, teaching procedures, and instructional materials.…

  4. Preliminary Bibliography on Africa South of the Sahara for Undergraduate Libraries.

    Science.gov (United States)

    Ehrman, Edith; Morehouse, Ward

    This classified bibliography on Africa south of the Sahara and similar bibliographies on South Asia (LI 000 061) and East Asia (LI 000 881) have been compiled under the first phase of a three-year cooperative project to strengthen bibliographical resources for undergraduate libraries on "neglected" foreign areas. The bibliography in its…

  5. Africa South of the Sahara: A Resource Guide for Secondary School Teachers. Interim Report.

    Science.gov (United States)

    Beyer, Barry K., Ed.

    Information to help educators develop a program of study about Africa south of the Sahara is presented in this guide for use with secondary school students. Appropriate objectives for a study of this region and its people are stated: the acquisition of sufficient information to make contemporary Africa intelligible, the formulation of concepts…

  6. Evaluation of Africa South of the Sahara. An Inquiry Program for Grades 7-10.

    Science.gov (United States)

    Beyer, Barry K.; And Others

    Project Africa, a social studies curriculum research and development project, is primarily engaged in testing new materials and techniques for teaching about Africa south of the Sahara in American secondary schools. The purpose of this technical report is to highlight the program's strengths and weaknesses from a variety of viewpoints -- those of…

  7. Le Sahara marocain : désenclavement et développement durable

    Directory of Open Access Journals (Sweden)

    EL MAHJOUB CHMOURK

    2012-04-01

    Full Text Available The Moroccan Sahara: opening-up and sustainable development. The enclosing of the Moroccan Sahara results from the inversion and old situation. Indeed, during a very long time, the area was a way of passage, a platform in the south of Morocco. In testify the Tran-Saharan commercial routes, which were the main transportation routes back in time, like the goal of integration of the area in the country and compared to western Africa. It is with the economic crisis, and even a political crisis causing a fold on itself of this area until 1975.Since Sahara belongs to Morocco, it still profits a considerable public effort to carry out its opening-up and its economic insertion within the country. Massive investments carried out by the State give to the area the structuring which it missed. Which are the aspects of the Sahara development? Which role played the State in this development? The intervention of the State contributes to bring effective solutions to the problem of the opening-up of this surrounding space?

  8. Reconstruction of exposure histories of meteorites from Antarctica and the Sahara

    Energy Technology Data Exchange (ETDEWEB)

    Neupert, U.; Neumann, S.; Leya, I.; Michel, R. [Hannover Univ. (Germany). Zentraleinrichtung fuer Strahlenschutz (ZfS); Kubik, P.W. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Bonani, G.; Hajdas, I.; Suter, M. [Eidgenoessische Technische Hochschule, Zurich (Switzerland)

    1997-09-01

    {sup 10}Be, {sup 14}C, and {sup 26}Al were analyzed in H-, L-, and LL-chondrites from the Acfer region in the Algerian Sahara and from the Allan Hills/Antarctica. Exposure histories and terrestrial ages could be determined. (author) 3 figs., 2 refs.

  9. Review: Steffen Wippel, Wirtschaft, Politik und Raum: Territoriale und regionale Prozesse in der westlichen Sahara (2012 Buchbesprechung: Steffen Wippel, Wirtschaft, Politik und Raum: Territoriale und regionale Prozesse in der westlichen Sahara (2012

    Directory of Open Access Journals (Sweden)

    Laurence Marfaing

    2013-01-01

    Full Text Available Review of the monograph:Steffen Wippel, Wirtschaft, Politik und Raum: Territoriale und regionale Prozesse in der westlichen Sahara, 2 volumes, Berlin/Tübingen: Verlag Hans Schiler, 2012, ISBN 9783899303674, xiv + 1,438 pagesBesprechung der Monographie:Steffen Wippel, Wirtschaft, Politik und Raum: Territoriale und regionale Prozesse in der westlichen Sahara, 2 Bände, Berlin/Tübingen: Verlag Hans Schiler, 2012, ISBN 9783899303674, xiv + 1,438 Seiten

  10. Preliminary comparative study of anti-inlfammatory effect of unheated and heat-treated Sahara honey:In vivo approach

    Institute of Scientific and Technical Information of China (English)

    Moussa Ahmed; Saad Aissat; Noureddine Djebli

    2015-01-01

    Objective:To investigate the effect of unheated and heat-treated of Sahara honey. Methods: A total of 24 Swiss albino mice weighing 25–35 g were divided into four groups (n = 6). Anti-inflammatory effect was assessed at 1, 2, 3, 4, 5 and 6 h after subplantar injection of carrageenan (0.5 mL of a 1% solution in normal saline). In addition, total phenolic content was determined by modified Folin-Ciocalteu method. Results: The total phenolic content capacity of the Sahara honey before and after heat treatment was between 72 and 97.9 mg of gallic acid equivalents/100 g of honey respectively. Administration of unheated honey (oral administration) reduced significantly (P Conclusions:Our results suggest that unheated Sahara honey has anti-inflammatory effects by reducing the mice paw edema size while heat-treated Sahara honey decreases the anti-inflammatory activity.

  11. [Cupressus dupreziana A. Camus: distribution, decline and regeneration on the Tassili n'Ajjer, central Sahara].

    Science.gov (United States)

    Abdoun, Fatiha; Beddiaf, Mohamed

    2002-05-01

    As soon as it was first discovered in 1924, on the heights of the Tassili n'Ajjer, Cupressus dupreziana (A. Camus) was declared an endangered species. The few ancient trees to be seen in the beds of wadis gave reason to suppose that they were isolated individuals left behind from a forest that had flourished in a damper climate. Attempts at a census of the trees were made on a number of occasions, the fullest, in 1972, reporting a total of 230 living specimens. The revision of this inventory between 1997 and 2001 has now enabled us to draw the boundaries of the present range of this species, to assess its rate of decline over the last three decades and, for the first time, to record some regeneration, with the presence of new, young trees.

  12. Organization of drainage networks from space imagery in the Tanezrouft plateau (Western Sahara) : implications for recent intracratonic deformations

    Science.gov (United States)

    Chorowicz, J.; Fabre, J.

    1997-12-01

    Analyses of satellite images (Landsat TM, SPOT and SAR ERS-1) of the Tanezrouft Plateau (Sahara) together with observations in the field have provided evidence of palaeo-drainage networks and intracratonic tectonic activity. The central network was a large braided system which collected waters from the western Hoggar in the Holocene. This network is connected northwesterly with Wadi Mouilah, the Reggan topographic depression and Sebkha Meqerghane. It is affected by conjugate northwest- and northeast-striking recent faults which reactivate older faults related to the north-south-trending Pan-African suture zone. The southern network comprises the wadis Tamanrasset, El Djouf and El Djouf his. They formerly constituted a large system running from southeast to northwest, captured and turning south in western Tanezrouft. This wadi system is presently cut into two parts as a result of recent tectonic deformations, i.e. uplift affecting the western border of the Tanezrouft plateau and north-striking faults paralleling the Pan-African suture zone.

  13. Viruses in the desert: a metagenomic survey of viral communities in four perennial ponds of the Mauritanian Sahara.

    Science.gov (United States)

    Fancello, Laura; Trape, Sébatien; Robert, Catherine; Boyer, Mickaël; Popgeorgiev, Nikolay; Raoult, Didier; Desnues, Christelle

    2013-02-01

    Here, we present the first metagenomic study of viral communities from four perennial ponds (gueltas) located in the central Sahara (Mauritania). Three of the four gueltas (Ilij, Molomhar and Hamdoun) are located at the source of three different wadis belonging to the same hydrologic basin, whereas the fourth (El Berbera) belongs to a different basin. Overall, sequences belonging to tailed bacteriophages were the most abundant in all four metagenomes although electron microscopy and sequencing confirmed the presence of other viral groups, such as large DNA viruses. We observed a decrease in the local viral biodiversity in El Berbera, a guelta with sustained human activities, compared with the pristine Ilij and Molomhar, and sequences related to viruses infecting crop pests were also detected as a probable consequence of the agricultural use of the soil. However, the structure of the El Berbera viral community shared the common global characteristics of the pristine gueltas, that is, it was dominated by Myoviridae and, more particularly, by virulent phages infecting photosynthetic cyanobacteria, such as Prochlorococcus and Synechococcus spp. In contrast, the Hamdoun viral community was characterized by a larger proportion of phages with the potential for a temperate lifestyle and by dominant species related to phages infecting heterotrophic bacteria commonly found in terrestrial environments. We hypothesized that the differences observed in the structural and functional composition of the Hamdoun viral community resulted from the critically low water level experienced by the guelta.

  14. Aspects of Insider Threats

    DEFF Research Database (Denmark)

    Probst, Christian W.; Hunker, Jeffrey; Gollmann, Dieter;

    2010-01-01

    The insider threat has received considerable attention, and is often cited as the most serious security problem. It is also considered the most difficult problem to deal with, because an “insider” has information and capabilities not known to external attackers. The difficulty in handling the ins...

  15. Resource Geopolitics: Cold War Technologies, Global Fertilizers, and the Fate of Western Sahara.

    Science.gov (United States)

    Camprubí, Lino

    2015-07-01

    When, after years of geological and geophysical exploration, a phosphate mine was discovered at Bu-Craa in 1964, Western Sahara received renewed geopolitical attention. Several countries competing for the control of the world fertilizer market, including Morocco, Spain, France, and the United States, developed diverging strategies to gain control of the mineral. After intense negotiations revolving around the materiality of mining technologies and involving reserve estimations, sabotage, and flexing of diplomatic muscles, Morocco took over the Spanish colony in 1975. While this secured Morocco's place in the world market, it condemned the local population to exile and domination. This article explores three technological stages of the exploitation of phosphate in Western Sahara that underpin the geopolitical history. This perspective yields new visions of cold war technology and postcolonial markets.

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

    Science.gov (United States)

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

    2013-01-01

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

  17. Revision of the genus Achmonia of Africa south of the Sahara (Coleoptera: Staphylinidae: Staphylininae).

    Science.gov (United States)

    Janák, Jiří; Bordoni, Arnaldo

    2014-10-09

    A redescription of the genus Achmonia Bordoni, 2004 is presented. Based on a revision of types and of additional material, seven species are recognized in Africa south of the Sahara and placed into two species groups. All species are described or redescribed and illustrated, four of them for the first time: Achmonia carinata sp. nov., A. kapangana sp. nov., A. knirschi sp. nov., and A. simulator sp. nov. A lectotype is designated for Xantholinus amabilis Boheman, 1848, Eulissus flavomarginatus Bernhauer, 1929 and E. congoensis Bernhauer, 1932. These species are transferred to Achmonia. A lectotype is designated for Eulissus semiflavus Bernhauer, 1913, and E. gerardi Bernhauer, 1929 and the following synonymy is proposed: Achmonia amabilis (Boheman, 1848) = Eulissus semiflavus Bernhauer, 1913, syn. nov. = Eulissus gerardi Bernhauer, 1929, syn. nov. The distribution of the genus in Africa south of Sahara is mapped and a key to species is presented.

  18. Improved performance of agriculture in Africa South of the Sahara: Taking off or bouncing back?

    OpenAIRE

    Nin-Pratt, Alejandro; Johnson, Michael E.; Yu, Bingxin

    2012-01-01

    The improved performance of the agricultural sector in Africa south of the Sahara during the most recent decade (2000–2010) has raised questions about the drivers behind the growth. Skeptics argue that rising commodity prices, as world markets experience a commodity boom, are the main cause of the agricultural growth. Others point to improvements in the policy environment and increased investments in agriculture at a time when African governments and donors have been rallying to increase th...

  19. Characterizing land surface phenology and responses to rainfall in the Sahara desert

    Science.gov (United States)

    Yan, Dong; Zhang, Xiaoyang; Yu, Yunyue; Guo, Wei; Hanan, Niall P.

    2016-08-01

    Land surface phenology (LSP) in the Sahara desert is poorly understood due to the difficulty in detecting subtle variations in vegetation greenness. This study examined the spatial and temporal patterns of LSP and its responses to rainfall seasonality in the Sahara desert. We first generated daily two-band enhanced vegetation index (EVI2) from half-hourly observations acquired by the Spinning Enhanced Visible and Infrared Imager on board the Meteosat Second Generation series of geostationary satellites from 2006 to 2012. The EVI2 time series was used to retrieve LSP based on the Hybrid Piecewise Logistic Model. We further investigated the associations of spatial and temporal patterns in LSP with those in rainfall seasonality derived from the daily rainfall time series of the Tropical Rainfall Measurement Mission. Results show that the spatial shifts in the start of the vegetation growing season generally follow the rainy season onset that is controlled by the summer rainfall regime in the southern Sahara desert. In contrast, the end of the growing season significantly lags the end of the rainy season without any significant dependence. Vegetation growing season can unfold during the dry seasons after onset is triggered during rainy seasons. Vegetation growing season can be as long as 300 days or more in some areas and years. However, the EVI2 amplitude and accumulation across the Sahara region was very low indicating sparse vegetation as expected in desert regions. EVI2 amplitude and accumulated EVI2 strongly depended on rainfall received during the growing season and the preceding dormancy period.

  20. Aridification of the Sahara desert caused by Tethys Sea shrinkage during the Late Miocene.

    Science.gov (United States)

    Zhang, Zhongshi; Ramstein, Gilles; Schuster, Mathieu; Li, Camille; Contoux, Camille; Yan, Qing

    2014-09-18

    It is widely believed that the Sahara desert is no more than ∼2-3 million years (Myr) old, with geological evidence showing a remarkable aridification of north Africa at the onset of the Quaternary ice ages. Before that time, north African aridity was mainly controlled by the African summer monsoon (ASM), which oscillated with Earth's orbital precession cycles. Afterwards, the Northern Hemisphere glaciation added an ice volume forcing on the ASM, which additionally oscillated with glacial-interglacial cycles. These findings led to the idea that the Sahara desert came into existence when the Northern Hemisphere glaciated ∼2-3 Myr ago. The later discovery, however, of aeolian dune deposits ∼7 Myr old suggested a much older age, although this interpretation is hotly challenged and there is no clear mechanism for aridification around this time. Here we use climate model simulations to identify the Tortonian stage (∼7-11 Myr ago) of the Late Miocene epoch as the pivotal period for triggering north African aridity and creating the Sahara desert. Through a set of experiments with the Norwegian Earth System Model and the Community Atmosphere Model, we demonstrate that the African summer monsoon was drastically weakened by the Tethys Sea shrinkage during the Tortonian, allowing arid, desert conditions to expand across north Africa. Not only did the Tethys shrinkage alter the mean climate of the region, it also enhanced the sensitivity of the African monsoon to orbital forcing, which subsequently became the major driver of Sahara extent fluctuations. These important climatic changes probably caused the shifts in Asian and African flora and fauna observed during the same period, with possible links to the emergence of early hominins in north Africa.

  1. Sahara et nomadisme. L’envers du décor

    Directory of Open Access Journals (Sweden)

    Hélène Claudot-Hawad

    2011-12-01

    Full Text Available Cette analyse concerne les interventions de l’État au Sahara et la façon dont les Toua­regs prolongent, transforment et adaptent leur nomadisme, dans un contexte de dépossession territoriale, politique et identitaire. Le nomadisme est étudié ici non seulement comme une pratique économique et un mode de vie impliquant un rapport particulier à l’espace, mais également comme une philosophie du mouvement.

  2. Aquatic community response in a groundwater-fed desert lake to Holocene desiccation of the Sahara

    Science.gov (United States)

    Eggermont, Hilde; Verschuren, Dirk; Fagot, Maureen; Rumes, Bob; Van Bocxlaer, Bert; Kröpelin, Stefan

    2008-12-01

    The finely laminated sediment record of a permanent, hypersaline, desert oasis lake in the Ounianga region of northeastern Chad presents a unique opportunity to document the hydrological evolution of this groundwater-fed aquatic ecosystem during mid- and late-Holocene desiccation of the Sahara. In this study we reconstruct long-term changes in zoobenthos and zooplankton communities of Lake Yoa as their early-Holocene freshwater habitat changed into the hypersaline conditions prevailing today. Chironomid production peaked during the fresh-to-saline transition period, then stabilized at about half that of the earlier freshwater ecosystem. Quantitative salinity inferences based on fossil chironomid assemblages indicate that the fresh-to-saline transition occurred fairly abruptly between ˜4100 and 3400 cal yr BP, but that the ecosystem was buffered against shorter-term climate fluctuations due to continuous inflow of fossil groundwater. The mixture of tropical-African and southern Palaearctic chironomid faunas in the Lake Yoa fossil record required us to address several methodological issues concerning chironomid-based salinity reconstruction, and the applicability of a calibration dataset based on tropical East and West African lakes to this Sahara desert locality. The most coherent reconstruction was obtained with an inference model that applies a weighted best-modern-analogue (WMAT) transfer function to the African calibration dataset expanded with six Sahara lakes.

  3. How hazardous is the Sahara Desert crossing for migratory birds? Indications from satellite tracking of raptors.

    Science.gov (United States)

    Strandberg, Roine; Klaassen, Raymond H G; Hake, Mikael; Alerstam, Thomas

    2010-06-23

    We investigated the risk associated with crossing the Sahara Desert for migrating birds by evaluating more than 90 journeys across this desert by four species of raptors (osprey Pandion haliaetus, honey buzzard Pernis apivorus, marsh harrier Circus aeruginosus and Eurasian hobby Falco subbuteo) recorded by satellite telemetry. Forty per cent of the crossings included events of aberrant behaviours, such as abrupt course changes, slow travel speeds, interruptions, aborted crossings followed by retreats from the desert and failed crossings due to death, indicating difficulties for the migrants. The mortality during the Sahara crossing was 31 per cent per crossing attempt for juveniles (first autumn migration), compared with only 2 per cent for adults (autumn and spring combined). Mortality associated with the Sahara passage made up a substantial fraction (up to about half for juveniles) of the total annual mortality, demonstrating that this passage has a profound influence on survival and fitness of migrants. Aberrant behaviours resulted in late arrival at the breeding grounds and an increased probability of breeding failure (carry-over effects). This study also demonstrates that satellite tracking can be a powerful method to reveal when and where birds are exposed to enhanced risk and mortality during their annual cycles.

  4. Airborne Particulate Threat Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Patrick Treado; Oksana Klueva; Jeffrey Beckstead

    2008-12-31

    Aerosol threat detection requires the ability to discern between threat agents and ambient background particulate matter (PM) encountered in the environment. To date, Raman imaging technology has been demonstrated as an effective strategy for the assessment of threat agents in the presence of specific, complex backgrounds. Expanding our understanding of the composition of ambient particulate matter background will improve the overall performance of Raman Chemical Imaging (RCI) detection strategies for the autonomous detection of airborne chemical and biological hazards. Improving RCI detection performance is strategic due to its potential to become a widely exploited detection approach by several U.S. government agencies. To improve the understanding of the ambient PM background with subsequent improvement in Raman threat detection capability, ChemImage undertook the Airborne Particulate Threat Assessment (APTA) Project in 2005-2008 through a collaborative effort with the National Energy Technology Laboratory (NETL), under cooperative agreement number DE-FC26-05NT42594. During Phase 1 of the program, a novel PM classification based on molecular composition was developed based on a comprehensive review of the scientific literature. In addition, testing protocols were developed for ambient PM characterization. A signature database was developed based on a variety of microanalytical techniques, including scanning electron microscopy, FT-IR microspectroscopy, optical microscopy, fluorescence and Raman chemical imaging techniques. An automated particle integrated collector and detector (APICD) prototype was developed for automated collection, deposition and detection of biothreat agents in background PM. During Phase 2 of the program, ChemImage continued to refine the understanding of ambient background composition. Additionally, ChemImage enhanced the APICD to provide improved autonomy, sensitivity and specificity. Deliverables included a Final Report detailing our

  5. Protected Areas in Tropical Africa: Assessing Threats and Conservation Activities

    Science.gov (United States)

    Tranquilli, Sandra; Abedi-Lartey, Michael; Abernethy, Katharine; Amsini, Fidèle; Asamoah, Augustus; Balangtaa, Cletus; Blake, Stephen; Bouanga, Estelle; Breuer, Thomas; Brncic, Terry M.; Campbell, Geneviève; Chancellor, Rebecca; Chapman, Colin A.; Davenport, Tim R. B.; Dunn, Andrew; Dupain, Jef; Ekobo, Atanga; Eno-Nku, Manasseh; Etoga, Gilles; Furuichi, Takeshi; Gatti, Sylvain; Ghiurghi, Andrea; Hashimoto, Chie; Hart, John A.; Head, Josephine; Hega, Martin; Herbinger, Ilka; Hicks, Thurston C.; Holbech, Lars H.; Huijbregts, Bas; Kühl, Hjalmar S.; Imong, Inaoyom; Yeno, Stephane Le-Duc; Linder, Joshua; Marshall, Phil; Lero, Peter Minasoma; Morgan, David; Mubalama, Leonard; N'Goran, Paul K.; Nicholas, Aaron; Nixon, Stuart; Normand, Emmanuelle; Nziguyimpa, Leonidas; Nzooh-Dongmo, Zacharie; Ofori-Amanfo, Richard; Ogunjemite, Babafemi G.; Petre, Charles-Albert; Rainey, Hugo J.; Regnaut, Sebastien; Robinson, Orume; Rundus, Aaron; Sanz, Crickette M.; Okon, David Tiku; Todd, Angelique; Warren, Ymke; Sommer, Volker

    2014-01-01

    Numerous protected areas (PAs) have been created in Africa to safeguard wildlife and other natural resources. However, significant threats from anthropogenic activities and decline of wildlife populations persist, while conservation efforts in most PAs are still minimal. We assessed the impact level of the most common threats to wildlife within PAs in tropical Africa and the relationship of conservation activities with threat impact level. We collated data on 98 PAs with tropical forest cover from 15 countries across West, Central and East Africa. For this, we assembled information about local threats as well as conservation activities from published and unpublished literature, and questionnaires sent to long-term field workers. We constructed general linear models to test the significance of specific conservation activities in relation to the threat impact level. Subsistence and commercial hunting were identified as the most common direct threats to wildlife and found to be most prevalent in West and Central Africa. Agriculture and logging represented the most common indirect threats, and were most prevalent in West Africa. We found that the long-term presence of conservation activities (such as law enforcement, research and tourism) was associated with lower threat impact levels. Our results highlight deficiencies in the management effectiveness of several PAs across tropical Africa, and conclude that PA management should invest more into conservation activities with long-term duration. PMID:25469888

  6. Protected areas in tropical Africa: assessing threats and conservation activities.

    Science.gov (United States)

    Tranquilli, Sandra; Abedi-Lartey, Michael; Abernethy, Katharine; Amsini, Fidèle; Asamoah, Augustus; Balangtaa, Cletus; Blake, Stephen; Bouanga, Estelle; Breuer, Thomas; Brncic, Terry M; Campbell, Geneviève; Chancellor, Rebecca; Chapman, Colin A; Davenport, Tim R B; Dunn, Andrew; Dupain, Jef; Ekobo, Atanga; Eno-Nku, Manasseh; Etoga, Gilles; Furuichi, Takeshi; Gatti, Sylvain; Ghiurghi, Andrea; Hashimoto, Chie; Hart, John A; Head, Josephine; Hega, Martin; Herbinger, Ilka; Hicks, Thurston C; Holbech, Lars H; Huijbregts, Bas; Kühl, Hjalmar S; Imong, Inaoyom; Yeno, Stephane Le-Duc; Linder, Joshua; Marshall, Phil; Lero, Peter Minasoma; Morgan, David; Mubalama, Leonard; N'Goran, Paul K; Nicholas, Aaron; Nixon, Stuart; Normand, Emmanuelle; Nziguyimpa, Leonidas; Nzooh-Dongmo, Zacharie; Ofori-Amanfo, Richard; Ogunjemite, Babafemi G; Petre, Charles-Albert; Rainey, Hugo J; Regnaut, Sebastien; Robinson, Orume; Rundus, Aaron; Sanz, Crickette M; Okon, David Tiku; Todd, Angelique; Warren, Ymke; Sommer, Volker

    2014-01-01

    Numerous protected areas (PAs) have been created in Africa to safeguard wildlife and other natural resources. However, significant threats from anthropogenic activities and decline of wildlife populations persist, while conservation efforts in most PAs are still minimal. We assessed the impact level of the most common threats to wildlife within PAs in tropical Africa and the relationship of conservation activities with threat impact level. We collated data on 98 PAs with tropical forest cover from 15 countries across West, Central and East Africa. For this, we assembled information about local threats as well as conservation activities from published and unpublished literature, and questionnaires sent to long-term field workers. We constructed general linear models to test the significance of specific conservation activities in relation to the threat impact level. Subsistence and commercial hunting were identified as the most common direct threats to wildlife and found to be most prevalent in West and Central Africa. Agriculture and logging represented the most common indirect threats, and were most prevalent in West Africa. We found that the long-term presence of conservation activities (such as law enforcement, research and tourism) was associated with lower threat impact levels. Our results highlight deficiencies in the management effectiveness of several PAs across tropical Africa, and conclude that PA management should invest more into conservation activities with long-term duration.

  7. Threat in dreams: an adaptation?

    Science.gov (United States)

    Malcolm-Smith, Susan; Solms, Mark; Turnbull, Oliver; Tredoux, Colin

    2008-12-01

    Revonsuo's influential Threat Simulation Theory (TST) predicts that people exposed to survival threats will have more threat dreams, and evince enhanced responses to dream threats, compared to those living in relatively safe conditions. Participants in a high crime area (South Africa: n=208) differed significantly from participants in a low crime area (Wales, UK: n=116) in having greater recent exposure to a life-threatening event (chi([1,N=186])(2)=14.84, pdreams (chi([1,N=287])(2)=6.11, pdream threats (Fisher's Exact test, p=.2478). Overall, the incidence of threat in dreams was extremely low-less than 20% of dreams featured realistic survival threats. Escape from dream threats occurred in less than 2% of dreams. We conclude that this evidence contradicts key aspects of TST.

  8. Nuclear Threats and Security

    OpenAIRE

    Garry Jacobs; Winston P. Nagan

    2012-01-01

    This article presents highlights and insights from the International Conference on “Nuclear Threats and Security” organized by the World Academy of Art and Science in association with the European Leadership Network and the Dag Hammarskjöld University College of International Relations and Diplomacy and sponsored by NATO at the Inter-University Centre, Dubrovnik on September 14-16, 2012. The conference examined important issues related to nuclear non-proliferation and disarmament, the legalit...

  9. Threat modeling designing for security

    CERN Document Server

    Shostack, Adam

    2014-01-01

    Adam Shostack is responsible for security development lifecycle threat modeling at Microsoft and is one of a handful of threat modeling experts in the world. Now, he is sharing his considerable expertise into this unique book. With pages of specific actionable advice, he details how to build better security into the design of systems, software, or services from the outset. You'll explore various threat modeling approaches, find out how to test your designs against threats, and learn effective ways to address threats that have been validated at Microsoft and other top companies. Systems secur

  10. The threat from without

    Directory of Open Access Journals (Sweden)

    Lassi Saressalo

    1987-01-01

    Full Text Available Of greatest importance in ethnic folklore are the recognised and unrecognised elements that are used when founding identity on tradition. For the aim of ethnic identification is to note and know the cultural features that connect me with people like me and separate me from people who are not like me. Every group and each of its members thus needs an opponent, a contact partner in order to identify itself. What about the Lapps? The ethnocentric values of ethnic folklore provide a model for this generalising comparison. 'They' are a potential danger, are unknown, strange, a threat from beyond the fells. They are sufficiently common for the group's ethnic feeling. It is here that we find tradition, folk tales, describing the community's traditional enemies, describing the threat from without, engendering preconceived ideas, conflicts and even war. The Lapps have never had an empire, they have never conquered others' territory, they have never engaged in systematic warfare against other peoples. For this reason Lapp tradition lacks an offensive ethnic folklore proper with emphasis on aggression, power, violence, heroism and an acceptance of the ideology of subordinating others. On the contrary,Lapp folklore is familiar with a tradition in which strangers are always threatening the Lapps' existence, plundering their territories, burning and destroying. The Lapp has always had to fight against alien powers, to give in or to outwit the great and powerful enemy. In the Lapp tradition the staalo represents an outside threat that cannot be directly concretised. If foes are regarded as concrete enemies that may be defeated in physical combat or that can be made to look ridiculous, a staalo is more mythical, more supranormal, more vague. One basic feature of the staalo tradition is that it only appears as one party to a conflict. The stories about the Lapp who succeeds in driving away a staalo threatening the community, to outwit the stupid giant or to kill

  11. Threats to international science

    Science.gov (United States)

    Kisslinger, Carl

    The role of nongovernmental organizations (NGOs) as effective agents for promoting world science is seriously threatened. It is ironic that the threat comes from Norway and Denmark, two countries that have demonstrated a deep commitment to individual freedom and human rights. Motivated by a sincere desire to express their strongest disapproval of the “apartheid” policies of the government of the Republic of South Africa, these countries have passed laws that have the effect of rejecting the International Council of Scientific Unions (ICSU) principles of nondiscrimination and free circulation of scientists.

  12. Antibacterial and antioxidant activities of three endemic plants from Algerian Sahara

    Directory of Open Access Journals (Sweden)

    ELmouloud Bouchouka

    2012-03-01

    Full Text Available Background. Saharan plants are known by their high content of antioxidant products like phenolic compounds due to the extreme climatic conditions. They constitute the basis of treatments used by local population for various diseases. The purposes of this study were to measure the total phenolic compounds and total fl avonoid compounds, to determine antioxidant capacity, and to evaluate the antibacterial activity of three wild Saharan medicinal plants. Material and methods. Hexane and ethyl acetate fractions of ethanol:water extract and the residu of the extracted aqueous layer of Ferula vesceritensis fruits, Genista saharae aerial parts and Zilla macropterae fruits were assayed to determine their antibacterial activity using the disc diffusion method against: Escherichia coli (ATCC 25922, Staphylococcus aureus (ATCC 25923 and Pseudomonas aeruginosa (ATCC 27853. In addition, the total phenolic compounds and total fl avonoids and antioxydant activity using DPPH test of ethyl acetate fractions (EAF of plant parts studied were investigated. Gallic acid, quercetin and vitamin C were used for these parameters. Results. Among the extracts tested, ethyl acetate fractions of all plants and hexane fraction of F. vesceritensis showed activity against S. aureus. Good activity was shown by EAF of G. saharae. According to the results, it is observed that Z. macropterae fruits possess a good antioxidant activity. Conclusion. The results indicate that the ethyl acetate fraction of G. sahara Aerial parts possesses a good antibacterial activity against S. aureus, which justifi es its use in traditional medicine for treating respiratory diseases. Furthermore, evaluation of in vitro antioxidant capacity of Ethyl acetate fractions of these plants, particular Z. macroptera fruits, has also provided interesting results. Zilla macroptera fruits may therefore be a good source of antioxidants.

  13. How much rainfall sustained a Green Sahara during the mid-Holocene?

    Science.gov (United States)

    Hopcroft, Peter; Valdes, Paul; Harper, Anna

    2016-04-01

    The present-day Sahara desert has periodically transformed to an area of lakes and vegetation during the Quaternary in response to orbitally-induced changes in the monsoon circulation. Coupled atmosphere-ocean general circulation model simulations of the mid-Holocene generally underestimate the required monsoon shift, casting doubt on the fidelity of these models. However, the climatic regime that characterised this period remains unclear. To address this, we applied an ensemble of dynamic vegetation model simulations using two different models: JULES (Joint UK Land Environment Simulator) a comprehensive land surface model, and LPJ (Lund-Potsdam-Jena model) a widely used dynamic vegetation model. The simulations are forced with a number of idealized climate scenarios, in which an observational climatology is progressively altered with imposed anomalies of precipitation and other related variables, including cloud cover and humidity. The applied anomalies are based on an ensemble of general circulation model simulations, and include seasonal variations but are spatially uniform across the region. When perturbing precipitation alone, a significant increase of at least 700mm/year is required to produce model simulations with non-negligible vegetation coverage in the Sahara region. Changes in related variables including cloud cover, surface radiation fluxes and humidity are found to be important in the models, as they modify the water balance and so affect plant growth. Including anomalies in all of these variables together reduces the precipitation change required for a Green Sahara compared to the case of increasing precipitation alone. We assess whether the precipitation changes implied by these vegetation model simulations are consistent with reconstructions for the mid-Holocene from pollen samples. Further, Earth System models predict precipitation increases that are significantly smaller than that inferred from these vegetation model simulations. Understanding

  14. Surface features on Sahara soil dust particles made visible by atomic force microscope (AFM) phase images

    Science.gov (United States)

    Helas, G.; Andreae, M. O.

    2008-10-01

    We show that atomic force microscopy (AFM) phase images can reveal surface features of soil dust particles, which are not evident using other microscopic methods. The non-contact AFM method is able to resolve topographical structures in the nanometer range as well as to uncover repulsive atomic forces and attractive van der Waals' forces, and thus gives insight to surface properties. Though the method does not allow quantitative assignment in terms of chemical compound description, it clearly shows deposits of distinguishable material on the surface. We apply this technique to dust aerosol particles from the Sahara collected over the Atlantic Ocean and describe micro-features on the surfaces of such particles.

  15. El papel de la ONU en el conflicto del Sahara Occidental

    OpenAIRE

    2013-01-01

    La democracia hoy: una mirada desde el temor a la El conflicto del Sahara Occidental comienza en el período de descolonización del continente africano, en la década de los setenta ms exactamente. Este confr. Acto se ha caracterizado por contar con dos tendencias que hasta el momento se presentan totalmente irreconciliables: los intereses de las partes, Marruecos y la República arave Saharaui Democrática (RASD), que han llegado a despertar la atención de otras naciones, quienes por efectos de ...

  16. How well do analyses capture dust-generating winds in the Sahara and Sahel?

    Science.gov (United States)

    Roberts, Alexander; Marsham, John; Knippertz, Peter; Parker, Douglas

    2016-04-01

    Airborne mineral dust is important for weather, climate and earth-system prediction. Uncertainty in winds, as well as the land-surface, are known to be key to model uncertainties for dust uplift. Recent research has shown that during the summer wet season in the Sahel strong winds generated by the cold outflow from organized convective systems are an important dust storm mechanism (so called haboobs), while over the inner Sahara nocturnal low-level jets forming on the pressure gradient around the heat low dominate. Together the Sahel and Sahara are the world's largest dust source. Until now there has been a severe shortage of data for evaluating models for this region. Here, we bring together new observations from the remote Sahara, made during the Fennec project, with Sahelian data from the African Monsoon Multidisciplinary Analysis (AMMA), to provide an unprecedented evaluation of dust-generating winds in the European Centre for Medium-Range Weather Forecasts ERA-Interim (ERA-I) reanalysis. Differences between observations and ERA-I are explored with specific attention to monsoon and non-monsoon influenced regions. The main results are: (1) High speed winds in instantaneous ERA-I grid-box mean winds are lacking compared to time-averaged wind speed observations; (2) agreement between ERA-I and observations is lower during the monsoon season, even in parts of the Sahara not directly affected by the monsoon; and (3) both the seasonal and diurnal variability is under-represented in ERA-I. ERA-I fails to capture the summertime maximum for monsoon-affected stations and seasonally, correlations between daily-mean ERA-I and observed winds vary from 0.8 to 0.4, with lower correlations for 3-hourly data. These differences demonstrate that the model used in the production of the ERA-I reanalysis is unable to represent some important dust uplift processes, especially during the monsoon season when moist convection plays a key role, and that the product is not sufficiently

  17. Categorizing threat : building and using a generic threat matrix.

    Energy Technology Data Exchange (ETDEWEB)

    Woodard, Laura; Veitch, Cynthia K.; Thomas, Sherry Reede; Duggan, David Patrick

    2007-09-01

    The key piece of knowledge necessary for building defenses capable of withstanding or surviving cyber and kinetic attacks is an understanding of the capabilities posed by threats to a government, function, or system. With the number of threats continuing to increase, it is no longer feasible to enumerate the capabilities of all known threats and then build defenses based on those threats that are considered, at the time, to be the most relevant. Exacerbating the problem for critical infrastructure entities is the fact that the majority of detailed threat information for higher-level threats is held in classified status and is not available for general use, such as the design of defenses and the development of mitigation strategies. To reduce the complexity of analyzing threat, the threat space must first be reduced. This is achieved by taking the continuous nature of the threat space and creating an abstraction that allows the entire space to be grouped, based on measurable attributes, into a small number of distinctly different levels. The work documented in this report is an effort to create such an abstraction.

  18. Nuclear Threats and Security

    Directory of Open Access Journals (Sweden)

    Garry Jacobs

    2012-10-01

    Full Text Available This article presents highlights and insights from the International Conference on “Nuclear Threats and Security” organized by the World Academy of Art and Science in association with the European Leadership Network and the Dag Hammarskjöld University College of International Relations and Diplomacy and sponsored by NATO at the Inter-University Centre, Dubrovnik on September 14-16, 2012. The conference examined important issues related to nuclear non-proliferation and disarmament, the legality of nuclear weapons and their use, illicit trade in nuclear materials, the dangers of nuclear terrorism, nuclear- and cyber-security. Papers and video recordings of the major presentations and session summaries can be found here.

  19. Activity patterns in the Sahara Desert: an interpretation based on cross-sectional geometric properties.

    Science.gov (United States)

    Nikita, Efthymia; Siew, Yun Ysi; Stock, Jay; Mattingly, David; Lahr, Marta Mirazón

    2011-11-01

    The Garamantian civilization flourished in modern Fezzan, Libya, between 900 BC and 500 AD, during which the aridification of the Sahara was well established. Study of the archaeological remains suggests a population successful at coping with a harsh environment of high and fluctuating temperatures and reduced water and food resources. This study explores the activity patterns of the Garamantes by means of cross-sectional geometric properties. Long bone diaphyseal shape and rigidity are compared between the Garamantes and populations from Egypt and Sudan, namely from the sites of Kerma, el-Badari, and Jebel Moya, to determine whether the Garamantian daily activities were more strenuous than those of other North African populations. Moreover, sexual dimorphism and bilateral asymmetry are assessed at an intra- and inter-population level. The inter-population comparisons showed the Garamantes not to be more robust than the comparative populations, suggesting that the daily Garamantian activities necessary for survival in the Sahara Desert did not generally impose greater loads than those of other North African populations. Sexual dimorphism and bilateral asymmetry in almost all geometric properties of the long limbs were comparatively low among the Garamantes. Only the lower limbs were significantly stronger among males than females, possibly due to higher levels of mobility associated with herding. The lack of systematic bilateral asymmetry in cross-sectional geometric properties may relate to the involvement of the population in bilaterally intensive activities or the lack of regular repetition of unilateral activities.

  20. Impact of Sahara dust transport on Cape Verde atmospheric element particles.

    Science.gov (United States)

    Almeida-Silva, M; Almeida, S M; Freitas, M C; Pio, C A; Nunes, T; Cardoso, J

    2013-01-01

    The objectives of this study were to (1) conduct an elemental characterization of airborne particles sampled in Cape Verde and (2) assess the influence of Sahara desert on local suspended particles. Particulate matter (PM(10)) was collected in Praia city (14°94'N; 23°49'W) with a low-volume sampler in order to characterize its chemical composition by k0-INAA. The filter samples were first weighed and subsequently irradiated at the Portuguese Research Reactor. Results showed that PM(10) concentrations in Cape Verde markedly exceeded the health-based air quality standards defined by the European Union (EU), World Health Organization (WHO), and U.S. Environmental Protection Agency (EPA), in part due to the influence of Sahara dust transport. The PM(10) composition was characterized essentially by high concentrations of elements originating from the soil (K, Sm, Co, Fe, Sc, Rb, Cr, Ce, and Ba) and sea (Na), and low concentrations of anthropogenic elements (As, Zn, and Sb). In addition, the high concentrations of PM measured in Cape Verde suggest that health of the population may be less affected compared with other sites where PM(10) concentrations are lower but more enriched with toxic elements.

  1. Eolian sediment responses to late Quaternary climate changes: Temporal and spatial patterns in the Sahara

    Science.gov (United States)

    Swezey, C.

    2001-01-01

    This paper presents a compilation of eolian-based records of late Quaternary climate changes in the Sahara. Although the data are relatively sparse, when viewed as a whole, they reveal a general pattern of widespread eolian sediment mobilization prior to 11,000 cal. years BP, eolian sediment stabilization from 11,000 to 5000 cal. years BP, and a return to widespread eolian sediment mobilization after 5000 cal. years BP. Furthermore, an eolian-based record from southern Tunisia reveals the existence of millennial-scale changes in eolian sediment behavior. These millennial-scale variations provide examples of eolian sediment responses to climate changes at a scale intermediate between seasonal and orbital ('Milankovitch') changes, and they are also coincident with abrupt atmospheric and oceanic changes. The general synchroneity of the eolian stratigraphic records and their coincidence with various oceanic and atmospheric changes suggest that global forcing mechanisms have influenced late Quaternary eolian sediment behavior in the Sahara. ?? 2001 Elsevier Science B.V.

  2. Quality and management of hot water of intercalary continental, northern Sahara of Algeria

    Science.gov (United States)

    Tifrani, Ala Eddine; Nezli, Imed Eddine

    2016-07-01

    The Algerian Sahara is the biggest desert in the world, and it is known by that the main climatic characters which are the high temperature and the low precipitations. The northern Sahara is a part of this big area, located on the south-east of Algeria. Due to the rarely and insufficient precipitations (1 to 180 mm per year) the need for water is a rising problem, so the main source are the ground water. There are three ground water aquifers in the area, the phreatic table, the terminal complex and the intercalary continental, our study is focused on the intercalary continental which is the biggest non recharged aquifer in the world, many studies national and international estimated the reserve of the water around 6 million m3. Existing between 1000 and 2000 m depth, this depth gives the water a lot of characterization which need to be noted and updated for example the temperature (around 50°C), and the high mineralization, because of the vast area and the difference in depths between wells, which is a reason of variety, the main goal is the determination of chemical and physical setting of this water.

  3. Coping with global environmental change, disasters and security. Threats, challenges, vulnerabilities and risks

    Energy Technology Data Exchange (ETDEWEB)

    Brauch, Hans Guenter [Freie Univ. Berlin (Germany). Dept. of Political and Social Sciences; UNU-EHS, Bonn (DE). College of Associated Scientists and Advisors (CASA); Oswald Spring, Ursula [National Univ. of Mexico, Cuernavaca (MX). Regional Multidisciplinary Research Centre (CRIM); Mesjasz, Czeslaw [Cracow Univ. of Exonomics (Poland). Faculty of Management; Grin, John [Amsterdam Univ. (Netherlands). Dept. of Political Science; Dutch Knowledge network for Systems Innovations and Transitions (KSI), Amsterdam (Netherlands); Kameri-Mbote, Patricia [Strathmore Univ., Nairobi (Kenya). Dept. of Law; International Environmental Law Research Centre, Nairobi (Kenya); Chourou, Bechir [Univ. of Tunis-Carthage, Hammam-Chatt (Tunisia); Dunay, Pal [Geneva Centre for Security Policy (Switzerland). International Training Course in Security Policy; Birkmann, Joern (eds.) [United Nations Univ. (UNU), Bonn (DE). Inst. for Environment and Human Security (EHS)

    2011-07-01

    This policy-focused Global Environmental and Human Security Handbook for the Anthropo-cene (GEHSHA) addresses new security threats, challenges, vulnerabilities and risks posed by global environmental change and disasters. In 6 forewords, 5 preface essays 95 peer reviewed chapcountries analyse in 10 parts concepts of military and political hard security and economic, social, environmental soft security with a regional focus on the Near East, North and Sub-Sahara Africa and Asia and on hazards in urban centres. The major focus is on coping with global environmental change: climate change, desertification, water, food and health and with hazards and strategies on social vulnerability and resilience building and scientific, international, regional and national political strategies, policies and measures including early warning of conflicts and hazards. The book proposes a political geo-ecology and discusses a 'Fourth Green Revolution' for the Anthropocene era of earth history. (orig.)

  4. Bio-threat microparticle simulants

    Science.gov (United States)

    Farquar, George Roy; Leif, Roald N

    2012-10-23

    A bio-threat simulant that includes a carrier and DNA encapsulated in the carrier. Also a method of making a simulant including the steps of providing a carrier and encapsulating DNA in the carrier to produce the bio-threat simulant.

  5. Bio-threat microparticle simulants

    Science.gov (United States)

    Farquar, George Roy; Leif, Roald

    2014-09-16

    A bio-threat simulant that includes a carrier and DNA encapsulated in the carrier. Also a method of making a simulant including the steps of providing a carrier and encapsulating DNA in the carrier to produce the bio-threat simulant.

  6. Psychoanalysis and the nuclear threat

    Energy Technology Data Exchange (ETDEWEB)

    Levine, H.B.; Jacobs, D.; Rubin, L.J.

    1988-01-01

    {ital Psychoanalysis and the Nuclear Threat} provides coverage of the dynamic and clinical considerations that follow from life in the nuclear age. Of special clinical interest are chapters dealing with the developmental consequences of the nuclear threat in childhood, adolescence, and adulthood, and those exploring the technical issues raised by the occurrence in analytic and psychotherapeutic hours of material related to the nuclear threat. Additional chapters bring a psychoanalytic perspective to bear on such issues as the need to have enemies, silence as the real crime, love, work, and survival in the nuclear age, the relationship of the nuclear threat to issues of mourning and melancholia, apocalyptic fantasies, the paranoid process, considerations of the possible impact of gender on the nuclear threat, and the application of psychoanalytic thinking to nuclear arms strategy. Finally, the volume includes the first case report in the English language---albeit a brief psychotherapy---involving the treatment of a Hiroshima survivor.

  7. Adverse drug reaction reports for cardiometabolic drugs from sub Sahara Africa: A study in VigiBase

    NARCIS (Netherlands)

    Berhe, Derbew F.; Juhlin, Kristina; Star, Kristina; Haaijer-Ruskamp, Flora M.; Michael, Kidane; Taxis, Katja; Mol, Peter G.M.

    2014-01-01

    Background: Many pharmacovigilance centers have been established in Sub Sahara Africa (SSA) in recent years. Their focus has been on ADRs to drugs for communicable diseases. Little is known about ADRs caused by drugs for cardiometabolic diseases, although its burden is increasing rapidly in SSA. Obj

  8. Images of Africa: A Report on What American Secondary School Students Know and Believe about Africa South of the Sahara.

    Science.gov (United States)

    Beyer, Barry K.; Hicks, E. Perry

    "Project Africa" surveyed selected seventh- and 12th-grade students in 24 states to determine (1) the specific nature of their images of Africa south of the Sahara, both before and after any formal study of this region, and (2) the types and accuracy of the students' knowledge about the region and its peoples. In one survey, students…

  9. Libraries in National Literacy Education Programmes in Africa South of the Sahara: The State-of-the-Art.

    Science.gov (United States)

    Newa, John M.

    1990-01-01

    Examines the involvement of public and village libraries in literacy and postliteracy programs in Africa south of the Sahara during the last two decades. Issues discussed include the extent of illiteracy in Black Africa, populations served by village libraries, African rural strategies of development, and the implications for library services. (44…

  10. Long-distance autumn migration across the Sahara by painted lady butterflies: exploiting resource pulses in the tropical savannah.

    Science.gov (United States)

    Stefanescu, Constantí; Soto, David X; Talavera, Gerard; Vila, Roger; Hobson, Keith A

    2016-10-01

    The painted lady, Vanessa cardui, is a migratory butterfly that performs an annual multi-generational migration between Europe and North Africa. Its seasonal appearance south of the Sahara in autumn is well known and has led to the suggestion that it results from extremely long migratory flights by European butterflies to seasonally exploit the Sahel and the tropical savannah. However, this possibility has remained unproven. Here, we analyse the isotopic composition of butterflies from seven European and seven African countries to provide new support for this hypothesis. Each individual was assigned a geographical natal origin, based on its wing stable hydrogen isotope (δ(2)Hw) value and a predicted δ(2)Hw basemap for Europe and northern Africa. Natal assignments of autumn migrants collected south of the Sahara confirmed long-distance movements (of 4000 km or more) starting in Europe. Samples from Maghreb revealed a mixed origin of migrants, with most individuals with a European origin, but others having originated in the Sahel. Therefore, autumn movements are not only directed to northwestern Africa, but also include southward and northward flights across the Sahara. Through this remarkable behaviour, the productive but highly seasonal region south of the Sahara is incorporated into the migratory circuit of V. cardui.

  11. A Senior High School Social Studies Unit on Africa South of the Sahara. World History Series, Bulletin No. 252.

    Science.gov (United States)

    Kelly, Harry; And Others

    This secondary level curriculum guide provides a program and identifies materials for the study of the history and culture of Africa south of the Sahara. The primary purpose of this course is to stimulate thought and to encourage students to make valid generalizations and intelligent assessments of the forces and events that have and are shaping…

  12. Preliminary comparative study of anti-inflmmatory effect of unheated and heat-treated Sahara honey: In vivo approach

    Directory of Open Access Journals (Sweden)

    Moussa Ahmed

    2015-11-01

    Full Text Available Objective: To investigate the effect of unheated and heat-treated of Sahara honey. Methods: A total of 24 Swiss albino mice weighing 25–35 g were divided into four groups (n = 6. Anti-inflammatory effect was assessed at 1, 2, 3, 4, 5 and 6 h after subplantar injection of carrageenan (0.5 mL of a 1% solution in normal saline. In addition, total phenolic content was determined by modified Folin-Ciocalteu method. Results: The total phenolic content capacity of the Sahara honey before and after heat treatment was between 72 and 97.9 mg of gallic acid equivalents/100 g of honey respectively. Administration of unheated honey (oral administration reduced significantly (P < 0.05. The carrageenan induced mice paw edema model at 1, 3 and 6 h for 21.85%, 5.43% and 80.43%, respectively. Administration of heat-treated honey showed insignificant inhibition of carrageenan and induced paw edema at 1 h (31.16%, 3 h (0.25% and 6 h (34.19%. The 50 mg/kg diclofenac exhibited percent reduction in paw volume 16.12%, 8.90% and 15.32% after 1 h, 3 h and 6 h, respectively, when compared with control animals. No toxicity was identified. Conclusions: Our results suggest that unheated Sahara honey has anti-inflammatory effects by reducing the mice paw edema size while heat-treated Sahara honey decreases the antiinflammatory activity.

  13. How Moral Threat Shapes Laypersons' Engagement With Science.

    Science.gov (United States)

    Bender, Jens; Rothmund, Tobias; Nauroth, Peter; Gollwitzer, Mario

    2016-12-01

    Laypersons' engagement with science has grown over the last decade, especially in Internet environments. While this development has many benefits, scientists also face the challenge of devaluation and public criticism by laypersons. Embedding this phenomenon in social-psychological theories and research on value-behavior correspondence, we investigated moral threat as a factor influencing laypersons' engagement with science. Across three studies, we hypothesized and found that moral values shape the way laypersons evaluate and communicate about science when these values are threatened in a given situation and central to people's self-concept. However, prior research on the underlying mechanism of moral threat effects cannot fully rule out value salience as an alternative explanation. To close this gap, we situationally induced value salience while varying the degree of moral threat (Study 3). Our findings indicate that moral threat amplifies the influence of moral values on laypersons' evaluation of science above and beyond value salience.

  14. Groundwater resources exploration in the Zug area (Tiris, Western Sahara); Prospeccion de recursos hidricos subterraneos en el area de Zug (Tiris, Sahara Occidental)

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, B.; Villarroya, F.; Rebollo, L. F.; Olaiz, A.; Lopez, J.

    2015-07-01

    The area of Zug is located in the southwestern corner of the Tiris dorsal, in the Western Sahara. The area is characterized by outcrops of materials, mainly gneisses of archaic age and fractured granitic rocks, which in the southern sector are covered by aeolian sand sheets. A hydrogeological survey of the territory has been carried out, and boreholes and dug wells have been located and analyzed and this information integrated with the sparse outcrops. Based on this study, two hydrogeological domains have been established: Zug and Azzefal. From the analysis of satellite images, field work, geophysical profiles, a well inventory and chemical analysis, three priority areas for the location of future water supply wells have been identified: 1) alluvial fans, preferably located on the slopes of the dikes that cross the Tiris dorsal; 2) sabkhas (salt flats) as places of con- centration of ephemeral runoff and subsurface infiltration of accumulated water; 3) highly fractured granitic areas. Some of these three cases coincide with existing wells in this area. Electrical tomography shows how, in specific locations, low resistivity values reach 50 metres, opening up the possibility of finding sufficient water to meet the aforementioned needs. The water quality is not suitable for human supply directly from the well without chemical treatment. The area is still full of opportunities for future research, but only when a more stable political situation exists. (Author)

  15. Toxoplasmosis: A global threat

    Directory of Open Access Journals (Sweden)

    João M Furtado

    2011-01-01

    Full Text Available Toxoplasmosis, a disease described worldwide, which is caused by the protozoan Toxoplasma gondii, commonly involves the retina. The disease has a higher impact in immunocompromised individuals and in congenital infection because of the severity of central nervous system involvement. Although simple prophylactic measures could reduce transmission, T. gondii seroprevalence is still high, especially in South America. Educational campaigns and the development of new drugs to prevent primary infection could potentially reduce the burden of the disease.

  16. Stereotype Threat as Validity Threat: The Anxiety-Sex-Threat Interaction

    Science.gov (United States)

    Delgado, Ana R.; Prieto, Gerardo

    2008-01-01

    Stereotype threat has been invoked to explain underperformance on a variety of groups for whom the stereotypes allege inferior cognitive abilities. In math testing, stereotype threat has been used to explain sex differences in test performance. This paper describes an experimental study on a large sample (n = 313), in which the role of anxiety and…

  17. Regional hydrogen roadmap. Project development framework for the Sahara Wind Project

    Energy Technology Data Exchange (ETDEWEB)

    Benhamou, Khalid [Sahara Wind Inc., Rabat (Morocco); Arbaoui, Abdelaziz [Ecole National Superieure des Arts et Metiers ENSAM Meknes (Morocco); Loudiyi, Khalid [Al Akhawayn Univ. (Morocco); Ould Mustapha, Sidi Mohamed [Nouakchott Univ. (Mauritania). Faculte des Sciences et Techniques

    2010-07-01

    The trade winds that blow along the Atlantic coast from Morocco to Senegal represent one of the the largest and most productive wind potentials available on earth. Because of the erratic nature of winds however, wind electricity cannot be integrated locally on any significant scale, unless mechanisms are developed for storing these intermittent renewable energies. Developing distributed wind energy solutions feeding into smaller electricity markets are essential for solving energy access issues and enabling the development of a local, viable renewable energy industry. These may be critical to address the region's economic challenges currently under pressure from Sub-Saharan migrant populations. Windelectrolysis for the production of hydrogen can be used in grid stabilization, as power storage, fuel or chemical feedstock in specific industries. The objective of the NATO SfP 'Sahara Trade Winds to Hydrogen' project is to support the region's universities through an applied research framework in partnership with industries where electrolysis applications are relevant. By powering two university campuses in Morocco and Mauritania with small grid connected wind turbines and 30 kW electrolyzers generating hydrogen for power back-up as part of ''green campus concepts'' we demonstrated that wind-electrolysis for the production of hydrogen could absorb larger quantities of cheap generated wind electricity in order to maximize renewable energy uptakes within the regions weaker grid infrastructures. Creating synergies with local industries to tap into a widely available renewable energy source opens new possibilities for end users such as utilities or mining industries when processing raw minerals, whose exports generates key incomes in regions most exposed to desertification and climate change issue. Initiated by Sahara Wind Inc. a company from the private sector, along with the Al Akhawayn University, the Ecole Nationale Superieure

  18. Mobbing, threats to employees

    Directory of Open Access Journals (Sweden)

    Tatjana Vene

    2012-02-01

    Full Text Available RQ: Is there a connection among perception of hostile and unethical communication, timely removal of causes and employee satisfaction?Purpose: Perceived mobbing in the organization, analysing causes and timely removal of them without any effect; achieve an environment of satisfied employees. The purpose is to study the relationship amongthe categories: perceiving mobbing, removing the effects, employee satisfaction.Methods: Qualitative research approach, method of interview by using the seven steps principles.Results: The findings clearly state that being aware of the negative factors and psychological abuse in organizations was present. The interview participants perceived different negative behaviours especially by the female population and from the side of superiors. In some organizations perceived negative factors are insults,insinuations, low wages, inadequate working day, competition, lobbying, and verbal threats. All negative factors lead to serious implications for employees, in which the organization can lose its reputation, productivity is reduced, costs of employment can increase with more sick leaves and in extreme cases, the results can be soserious that the organization can end in bankruptcy or liquidation.Organization: The result of the study warns management to acceptcertain actions and remediate the situation in organizations. The employer and managers must do everything to protect their subordinates from violence and potential offenders.Society: The research study warns on the seriousness of mobbing among employees, the aim is to bring the issue to individuals and society. The victim usually needs help (health costs, losses in the pension system, increased unemployment, and lower productivity of the whole society.Originality: In view of the sensitivity of the issues, the author concludes that the existing research studies are based especially on closed questions (questionnaires; however, interviews create mutual trust between

  19. Modelling ultraviolet threats

    Science.gov (United States)

    James, I.

    2016-10-01

    Electro-optically (EO) guided surface to air missiles (SAM) have developed to use Ultraviolet (UV) wavebands supplementary to the more common Infrared (IR) wavebands. Missiles such as the US Stinger have been around for some time but are not considered a proliferation risk. The Chinese FN-16 and Russian SA-29 (Verba) are considered a much higher proliferation risk. As a result, models of the missile seekers must be developed to understand the characteristics of the seeker and the potential performance enhancement that are included. Therefore, the purpose of this paper is to introduce the steps that have been taken to characterise and model these missiles. It begins by outlining some of the characteristics of the threats, the key elements of a UV scene, the potential choice of waveband for a detector, the initial modelling work to represent the UV detector of the missile and presents initial results. The modelling shows that the UV detection range of a typical aircraft is dependent on both the size of the aircraft and its reflectivity. However, the strength of this correlation is less than expected. As a result, further work is required to model more seeker types and to investigate what is causing the weak correlations found in these initial investigations. In addition, there needs to be further study of the sensitivities of the model to other variables, such as the modelled detectivity of the detector and the signal to noise ratio assumed. Overall, the outcome of this work will be to provide specifications for aircraft size and reflectivity that limit the effectiveness of the UV channels.

  20. Forsterite and Olivine in Sahara-97210 (LL3.2) and Chainpur (LL3.4) Chondrules: Compositional Evolution and the Influence of Melting

    Science.gov (United States)

    Ruzicka, A.; Floss, C.

    2004-01-01

    It is generally accepted that chondrules contain relict grains that did not crystallize in situ, and that forsterite is one type of relict grain which is a likely precursor for chondrules. Chemically and morphologically similar forsterite is also found as "isolated grains", especially in carbonaceous chondrites. Using SIMS, we analyzed forsterite, ferrous overgrowths around forsterite, and coexisting normal olivine in 5 chondrules and 2 isolated grains in the Sahara-97210 ('Sahara") LL3.2 chondrite. We earlier used the same methods to study olivine in 3 Chainpur chondrules that contain relict forsterite. Our new data for Sahara provide additional insight into the processes affecting chondrules and their precursors.

  1. Global Threats to Child Safety.

    Science.gov (United States)

    Mace, Sharon E

    2016-02-01

    Children have rights, as enumerated in the Declaration of the Rights of the Child, and need protection from violence, exploitation, and abuse. Global threats to child safety exist. These threats include lack of basic needs (food, clean water, sanitation), maltreatment, abandonment, child labor, child marriage, female genital mutilation, child trafficking, disasters, and armed conflicts/wars. Recent disasters and armed conflicts have led to a record number of displaced people especially children and their families. Strategies and specific programs can be developed and implemented for eliminating threats to the safety of children.

  2. Surface features on Sahara soil dust particles made visible by atomic force microscope (AFM phase images

    Directory of Open Access Journals (Sweden)

    M. O. Andreae

    2008-10-01

    Full Text Available We show that atomic force microscopy (AFM phase images can reveal surface features of soil dust particles, which are not evident using other microscopic methods. The non-contact AFM method is able to resolve topographical structures in the nanometer range as well as to uncover repulsive atomic forces and attractive van der Waals' forces, and thus gives insight to surface properties. Though the method does not allow quantitative assignment in terms of chemical compound description, it clearly shows deposits of distinguishable material on the surface. We apply this technique to dust aerosol particles from the Sahara collected over the Atlantic Ocean and describe micro-features on the surfaces of such particles.

  3. Surface features on Sahara soil dust particles made visible by atomic force microscope (AFM phase images

    Directory of Open Access Journals (Sweden)

    G. Helas

    2008-08-01

    Full Text Available We show that atomic force microscopy (AFM phase images can reveal surface features of soil dust particles, which are not evident using other microscopic methods. The non-contact AFM method is able to resolve topographical structures in the nanometer range as well as to uncover repulsive atomic forces and attractive van der Waals' forces, and thus gives insight to surface properties. Though the method does not allow quantitative assignment in terms of chemical compound description, it clearly shows deposits of distinguishable material on the surface. We apply this technique to dust aerosol particles from the Sahara collected over the Atlantic Ocean and describe micro-features on the surfaces of such particles.

  4. Wars Without Beginning or End: Violent Political Organizations and Irregular Warfare in the Sahel-Sahara

    CERN Document Server

    Walther, Olivier; Skillicorn, David

    2016-01-01

    This article examines the structure and spatial patterns of violent political organizations in the Sahel-Sahara, a region characterized by growing political instability over the last 20 years. Drawing on a public collection of disaggregated data, the article uses network science to represent alliances and conflicts of 179 organizations that were involved in violent events between 1997 and 2014. To this end, we combine two spectral embedding techniques that have previously been considered separately: one for directed graphs (relationships are asymmetric), and one for signed graphs (relationships are positive or negative). Our result show that groups that are net attackers are indistinguishable at the level of their individual behavior, but clearly separate into pro- and anti-political violence based on the groups to which they are close. The second part of the article maps a series of 389 events related to nine Trans-Saharan Islamist groups between 2004 and 2014. Spatial analysis suggests that cross-border mov...

  5. Structure, composition, and location of organic matter in the enstatite chondrite Sahara 97096 (EH3)

    CERN Document Server

    Piani, Laurette; Beyssac, Olivier; Binet, Laurent; Bourot-Denise, Michèle; Derenne, Sylvie; Guillou, Corentin Le; Marrocchi, Yves; Mostefaoui, Smail; Rouzaud, Jean-Noel; Thomen, Aurelien

    2015-01-01

    The insoluble organic matter (IOM) of an unequilibrated enstatite chondrite Sahara (SAH) 97096 has been investigated using a battery of analytical techniques. As the enstatite chondrites are thought to have formed in a reduced environment at higher temperatures than carbonaceous chondrites, they constitute an interesting comparative material to test the heterogeneities of the IOM in the solar system and to constrain the processes that could affect IOM during solar system evolution. The SAH 97096 IOM is found in situ: as submicrometer grains in the network of fine-grained matrix occurring mostly around chondrules and as inclusions in metallic nodules, where the carbonaceous matter appears to be more graphitized. IOM in these two settings has very similar $\\delta^{15}N$ and $\\delta^{13}C$; this supports the idea that graphitized inclusions in metal could be formed by metal catalytic graphitization of matrix IOM. A detailed comparison between the IOM extracted from a fresh part and a terrestrially weathered part...

  6. Global Sea Level Stabilization-Sand Dune Fixation: A Solar-powered Sahara Seawater Textile Pipeline

    CERN Document Server

    Badescu, Viorel; Bolonkin, Alexander A

    2007-01-01

    Could anthropogenic saturation with pumped seawater of the porous ground of active sand dune fields in major deserts (e.g., the westernmost Sahara) cause a beneficial reduction of global sea level? Seawater extraction from the ocean, and its deposition on deserted sand dune fields in Mauritania and elsewhere via a Solar-powered Seawater Textile Pipeline (SSTP) can thwart the postulated future global sea level. Thus, Macro-engineering offers an additional cure for anticipated coastal change, driven by global sea level rise, that could supplement, or substitute for (1) stabilizing the shoreline with costly defensive public works (armoring macroprojects) and (2) permanent retreat from the existing shoreline (real and capital property abandonment). We propose Macro-engineering use tactical technologies that sculpt and vegetate barren near-coast sand dune fields with seawater, seawater that would otherwise, as commonly postulated, enlarge Earth seascape area! Our Macro-engineering speculation blends eremology with...

  7. Local Human Development in contexts of permanent crisis: Women’s experiences in the Western Sahara

    Directory of Open Access Journals (Sweden)

    María López Belloso

    2009-04-01

    Full Text Available Sahrawi women are active agents in the social dynamics of the refugee camps, in which they have developeda number of coping strategies to overcome the hardships of a deteriorating humanitarian situation. Since the outbreak of the con#ict and the forced settlement in Tindouf, Algeria, women have been responsible for the entire management of refugee camps, assuming leadership roles in many sectors of society.This paper highlights the Sahrawi women’s contribution to the process of local human development in a context of protracted refuge such as the one in the Western Sahara. In addition to the enlargement of the refugee population’s capacities in relation to material and physical assets, social and organizational abilities, and motivational strengths, one of the major achievements of Sahrawi women has been their own individual and collective process of empowerment within the camp life.

  8. Comparison of efifcacy of unheated and heat-treated Sahara honey on wound healing in rabbits

    Institute of Scientific and Technical Information of China (English)

    Baghdad Khiati; Moussa Ahmed

    2015-01-01

    Objective:To investigate the efficacy of unheated and heat-treated Sahara honey on wound healing in rabbits on the basis of macroscopic observation changes. Methods:Eight female rabbits were used. Using aseptic surgical technique, a 3 cm incision was made on the back of each rabbit and two rabbits with injuries in each group were treated daily with a topical application of unheated and heated honey, sulfadiazine and sterile saline, respectively. Results:The unheated honey demonstrated the highest activity on the wound compared to reference ointment silver sulfadiazine, heat-treated honey and sterile saline respectively. Further the present investigation proves that unheated honey is possessing superior wound healing activity than that of heat-treated honey. Conclusions:The result of this study confirms that unheated honey had the best wound healing effect even better than heat-treated honey.

  9. Dust and Biological Aerosols from the Sahara and Asia Influence Precipitation in the Western US

    Energy Technology Data Exchange (ETDEWEB)

    Creamean, Jessie; Suski, Kaitlyn; Rosenfeld, Daniel; Cazorla, Alberto; DeMott, Paul J.; Sullivan, Ryan C.; White, Allen B.; Ralph, F. M.; Minnis, Patrick; Comstock, Jennifer M.; Tomlinson, Jason M.; Prather, Kimberly

    2013-03-29

    Winter storms in California’s Sierra Nevada increase seasonal snowpack and provide critical water resources for the state. Thus, the mechanisms influencing precipitation in this region have been the subject of research for decades. Previous studies suggest Asian dust enhances cloud ice and precipitation (1), while few studies consider biological aerosols as an important global source of ice nuclei (IN). Here, we show that dust and biological aerosols transported from as far as the Sahara were present in glaciated high-altitude clouds coincident with elevated IN concentrations and ice-induced precipitation. This study presents the first direct cloud and precipitation measurements showing that Saharan and Asian dust and biological aerosols likely serve as IN and play an important role in orographic precipitation processes over the western United States.

  10. Microbial diversity and organic matter fractions under two arid soils in Algerian Sahara

    Science.gov (United States)

    Karabi, Mokhtar; Hamdi, Aissa Baelhadj; Zenkhri, Salah

    2016-07-01

    The Algerian Sahara is characterized by a heterogeneity of edaphic conditions and climatic dissimilarities; however, information on biological indicators of arid soils is weakly documented in this area. The researchers who have studied the biological activities of the soils of the arid regions have underlined their low organic matter content, particularly their very low rates of organic nitrogen; a low humification because seriously inhibited by a significant mineralization. The objective of the current work is to study the microbial biomass densities and organic matter fractions for different types of soil, under two arid soil in Algerian Sahara. The experiment was conducted in an alluvial soil in traditional palm grove of Guerrara, and in a saline soil in experimental field of university of Ouargla. Composite soil samples (10 subsamples each) were collected aseptically at 0-20 cm depth on two diagonal transects drawn over an area of 12 ha. The following germs densities were determined: Bacteria, Fungi and Actinomycetes. The soil organic matter fractions, the textural fractions, chemical attributes (organic C, total N, total limestone and gypsum) were also determined. The microbial groups count on both soils reveals that the bacterianmicroflora present a numerical superiority followed by the actinomycetes and finally fungi. The micro-organisms densities except fungal density, showed a prevalence of the bacterianmicroflora, and actinomycetes in alluvial soil compared to saline soil. Fractionation of soil organic matter show that all fractions are better represented in alluvial soil except non-extractable organic carbon (NEOC) which are better represented in saline soil. This confirms that alluvial soil has a relatively large biological activity than saline soil and that humification process is relatively pronounced by comparing it with the saline soil, which tends to contain little polycondenseshumic compounds.

  11. The Sahara from the Middle Jurassic to the Middle Cretaceous: Data on environments and climates based on outcrops in the Algerian Sahara

    Science.gov (United States)

    Busson, G.; Cornée, A.

    The period investigated, succeeded the Upper Triassic and Liassic-Lower Dogger arid sedimentation which was characterized by the development of large evaporitic deposits. The north-eastern part of the Algerian Sahara is specially interesting as it constitutes part of the few dated continental Jurassic outcrops in North Africa (except in the Maghreb). Continental Lower-Middle Cretaceous is also well developed in the same region. The grading of these continental series into marine series particularly in the north-eastern part of the Maghreb has been investigated from an adequate number of well spaced wells. The Middle-Upper Jurassic (Lower Taouratine) consists of an argillaceous-sandy-ferruginous series, often grey coloured and rich in filicean wood and vertebrate remains in some levels. The ferralitic alteration products denote a more humid climate than that which prevailed during the Liassic-Lower-Dogger times. These products alternate with sandy conglomeratic events confirming the influences of alternating important run-off and aeolian winnowing. The large continental Lower and Middle Cretaceous detrital nappes are discussed. They constitute the uppermost part of the series, south of the Tinrhert Hamada (Alba-Vraconian series with the more detrital lateral equivalent), west of Tademait (Gara Samani). Data on lithology and paleobiology (fishes, Dinosaurs, other vertebrates, pelecypods, gastropods, wood debris, palynoflora) permit the reconstruction of the palaeo-environment and the conditions of deposition. This is similar to the sub-desertic terrestrial sedimentation by violent and ephemeral hydrodynamism model based on the modern Darfour example. The desertic conditions which prevailed in these Saharan areas during the Cretaceous are reflected as well as their possible consequences on the sedimentation of nearby oceanic areas (Atlantic and Tethys). This detrital sedimentation is finally reviewed in the context of its tectonic origins and an attempt is made to

  12. A comparison of the physical properties of desert dust retrieved from the sunphotometer observation of major events in the Sahara, Sahel, and Arabian Peninsula

    KAUST Repository

    Masmoudi, Mohamed

    2015-05-01

    © 2015 Elsevier B.V. The objective of this work is to assess the variability of the size-distribution, real (n) and imaginary (k) parts of the refractive index, asymmetry parameter (g), and single scattering albedo (SSA) of desert dust events observed in the Sahara, Sahel, and Arabian Peninsula areas. For this we use the level-2 inversions of 14 AERONET sunphotometers representative of the area of study. In the dataset, the dust-dominated events are discriminated on the basis of their large optical depth and low (<. 0.3) Ångström exponent (α) calculated between 440. nm and 870. nm. In all the volume size-distributions a coarse mode (CM) of particles is observed but a fine mode (FM) of particles with radii. <. 0.2. μm is also present. The volume fraction represented by the FM is lower (3%) during the most intense dust storms than during moderate ones (12%). The inter-site variability of the characteristics of the CM-dominated situations is found to be non-significant and at 440, 675, 870, and 1020. nm a common set of values can be adopted for n (1.54 ± 0.03, 1.53 ± 0.02, 1.50 ± 0.02, 1.48 ± 0.02), k (0.0037 ± 0.0007, 0.0012 ± 0.0002, 0.0011 ± 0.0002, 0.0012 ± 0.0002), g (0.77 ± 0.01, 0.74 ± 0.01, 0.73 ± 0.01, 0.74 ± 0.01), and the SSA (0.90 ± 0.02, 0.97 ± 0.01, 0.98 ± 0.01, 0.98 ± 0.01). However; during the less intense dust-events the growing influence of the FM leads to regional differentiation of the dust properties and 2 main areas can be distinguished: 1) the relatively clean central Sahara/Sahel, and 2) the more polluted continuum constituted by the Mediterranean coast and the Arabian Peninsula.

  13. Dengue: a global threat.

    Science.gov (United States)

    Thisyakorn, Usa; Thisyakorn, Chule

    2015-01-01

    Dengue, a mosquito-borne viral disease, is currently an expanding global problem. The disease is caused by four closely related dengue serotypes; it ranges from asymptomatic infection to undifferentiated fever, dengue fever (DF) and dengue hemorrhagic fever (DHF). DHF is characterized by fever, bleeding diathesis and a tendency to develop apotentially fatal shock syndrome. Dengue infection with organ impairment mainly involves the central nervous system and liver. Consistent hematological findings include vasculopathy, coagulopathy and thrombocytopenia. Laboratory diagnoses include virus isolation, serology, and detection ofdengue ribonucleic acid. Successful treatment, which is mainly supportive, depends on early recognition of the disease and careful monitoring for shock. A severity-based revised dengue classification for medical interventions has been developed and validated in many countries. So far however, there has not been any specific dengue treatment; prevention is currently limited to vector control measures. The world's first, large-scale dengue vaccine, efficacy study demonstrated its efficacy and a reduction of dengue's severity in a study of more than 10,000 volunteers in Asia. Initial safety data are consistent with a good safety profile.

  14. DENGUE: GLOBAL THREAT.

    Science.gov (United States)

    Thisyakorn, Usa; Thisyakorn, Chule

    2015-01-01

    Dengue is a mosquito-borne viral disease, which is currently an expanding global problem. Four closely related dengue serotypes cause the disease, which ranges from asymptomatic infection to undifferentiated fever, dengue fever (DF), and dengue hemorrhagic fever (DHF). DHF is characterized by fever, bleeding diathesis, and a tendency to develop a potentially fatal shock syndrome. Dengue infection with organ impairment mainly involves the central nervous system and the liver. Consistent hematological findings include vasculopathy, coagulopathy, and thrombocytopenia. Laboratory diagnosis includes virus isolation, serology, and detection of dengue ribonucleic acid. Successful treatment, which is mainly supportive, depends on early recognition of the disease and careful monitoring for shock. A severity-based revised dengue classification for medical interventions has been developed and validated in many countries. There is no specific dengue treatment, and prevention is currently limited to vector control measures. The world's first, large-scale dengue vaccine efficacy study demonstrated its efficacy and a reduction of dengue disease severity with a good safety profile in a study of more than 30,000 volunteers from Asia and Latin America.

  15. Geochemical and mineralogical evidence for Sahara and Sahel dust additions to Quaternary soils on Lanzarote, eastern Canary Islands, Spain

    Science.gov (United States)

    Muhs, D.R.; Budahn, J.; Skipp, G.; Prospero, J.M.; Patterson, D.; Bettis, E. Arthur

    2010-01-01

    Africa is the most important source of dust in the world today, and dust storms are frequent on the nearby Canary Islands. Previous workers have inferred that the Sahara is the most important source of dust to Canary Islands soils, with little contribution from the Sahel region. Soils overlying a late Quaternary basalt flow on Lanzarote, Canary Islands, contain, in addition to volcanic minerals, quartz and mica, exotic to the island's bedrock. Kaolinite in the soils also likely has an exotic origin. Trace-element geochemistry shows that the soils are derived from varying proportions of locally derived basalt and African dust. Major-element geochemistry, clay mineralogy and interpretation of satellite imagery suggest that dust additions to the Canary Islands come not only from the Sahara Desert, but also from the Sahel region. ?? Published 2010. This article is a US Government work and is in the public domain in the USA.

  16. Threat image projection in CCTV

    Science.gov (United States)

    Neil, David; Thomas, Nicola; Baker, Bob

    2007-10-01

    Operators are key components in a Closed Circuit Television (CCTV) system, being the link between the system technology and its effective use. Operators' performance will largely determine the level of service provided by the system. There have been few studies testing operator performance, while much work has been done to test the performance of the technology. Previous work on CCTV operator performance carried out by the Home Office Scientific Development Branch (HOSDB) has used filmed video and subjects who knew they were undergoing testing, meaning subjects are likely to be concentrating harder on performing well. HOSDB believes that there is a need for a test that would be able to be routinely used in a CCTV control room throughout the course of a normal shift to provide management with operational performance data. Threat Image Projection (TIP) is routinely used in X-Ray baggage scanners to keep operators alert to possible threats. At random intervals, a threat target image is superimposed over the image of the baggage being screened. The operator then responds to this threat. A similar system could be used for CCTV operators. A threat image would be randomly superimposed over the live CCTV feed and the operator would be expected to respond to this.

  17. The population threat.

    Science.gov (United States)

    Teitelbaum, M S

    1992-01-01

    contraints urged by Malthus. US policies in the 1980s amounted to defunding of population programs and ideological suppression. Seven steps in US policy change are indicated. Centralization of responsibilities for population issues should be determined within government; the Department of State or the National Security Council are likely choices.

  18. Cyber threats within civil aviation

    Science.gov (United States)

    Heitner, Kerri A.

    Existing security policies in civil aviation do not adequately protect against evolving cyber threats. Cybersecurity has been recognized as a top priority among some aviation industry leaders. Heightened concerns regarding cyber threats and vulnerabilities surround components utilized in compliance with the Federal Aviation Administration's (FAA) Next Generation Air Transportation (NextGen) implementation. Automated Dependent Surveillance-B (ADS-B) and Electronic Flight Bags (EFB) have both been exploited through the research of experienced computer security professionals. Civil aviation is essential to international infrastructure and if its critical assets were compromised, it could pose a great risk to public safety and financial infrastructure. The purpose of this research was to raise awareness of aircraft system vulnerabilities in order to provoke change among current national and international cybersecurity policies, procedures and standards. Although the education of cyber threats is increasing in the aviation industry, there is not enough urgency when creating cybersecurity policies. This project intended to answer the following questions: What are the cyber threats to ADS-B of an aircraft in-flight? What are the cyber threats to EFB? What is the aviation industry's response to the issue of cybersecurity and in-flight safety? ADS-B remains unencrypted while the FAA's mandate to implement this system is rapidly approaching. The cyber threat of both portable and non-portable EFB's have received increased publicity, however, airlines are not responding quick enough (if at all) to create policies for the use of these devices. Collectively, the aviation industry is not being proactive enough to protect its aircraft or airport network systems. That is not to say there are not leaders in cybersecurity advancement. These proactive organizations must set the standard for the future to better protect society and it's most reliable form of transportation.

  19. Strengths, weaknesses, opportunities and threats

    DEFF Research Database (Denmark)

    Bull, J. W.; Jobstvogt, N.; Böhnke-Henrichs, A.;

    2016-01-01

    environmental awareness. Threats include resistance to change, and difficulty with interdisciplinary collaboration. Consideration of SWOT themes suggested five strategic areas for developing and implementing ES.The ES concept could improve decision-making related to natural resource use, and interpretation...... facilitate interdisciplinary research, ensuring decision-making that supports sustainable development........ Such an assessment could form the basis for improving ES thinking, further embedding it into environmental decisions and management.The Young Ecosystem Services Specialists (YESS) completed a Strengths-Weaknesses-Opportunities-Threats (SWOT) analysis of ES through YESS member surveys. Strengths include the approach...

  20. Looming vulnerability to threat: a cognitive paradigm for anxiety.

    Science.gov (United States)

    Riskind, J H

    1997-08-01

    The concept that perceived threat or danger is a cognitive antecedent of anxiety is central in clinical psychology, personality psychology, and social psychology. The aim in the current article is to review this concept and present a new conception called the looming vulnerability model. Looming vulnerability is conceptualized as an important cognitive component of threat or danger that elicits anxiety, sensitizes the individual to signs of movement and threat, biases cognitive processing, and makes the anxiety more persistent and less likely to habituate. In addition, it is postulated as a principal theme that discriminates anxiety and focal fears from depression. The looming vulnerability model integrates a disparate collection of findings and integrates the conceptualization of anxiety and fear with ethological and developmental observations. The social-cognitive and evolutionary basis of the sense of looming vulnerability are discussed, as well as its roots in cognitive schemata (fear scripts), its state elicitation by several potential classes of antecedent conditions, and possible treatment implications.

  1. Spatial distribution of dust's optical properties over the Sahara and Asia inferred from Moderate Resolution Imaging Spectroradiometer

    Directory of Open Access Journals (Sweden)

    M. Yoshida

    2012-12-01

    Full Text Available There is a great deal of uncertainty surrounding the role of mineral dust aerosols in the earth's climate system. One reason for this uncertainty is that the optical properties of mineral dust, such as its single scattering albedo (the ratio of scattering to total extinction, are poorly understood because ground observations are limited to several locations and the satellite standard products are not available due to the excessively bright surface of the desert in the visible wavelength. We develop a method in this paper to estimate the spatial distributions of the aerosol single scattering albedo (ω0 and optical depth (τa, with daily 1 degree latitude and 1 degree longitude resolution, using data from Moderate Resolution Imaging Spectroradiometer (MODIS, as well as model simulations of radiative transfer. This approach is based on the "critical surface reflectance" method developed in the literature, which estimates ω0 from the top of the atmospheric radiance. We confirm that the uncertainties in our estimation of ω0 and τa are suitably minor and that the characteristic spatial distributions estimated over the Sahara and Asia are significant. The results for the Sahara indicate good correlation between ω0 and the surface reflectance and between ω0 and τa. Therefore, ω0 is determined mainly by the mineral composition of surface dust and/or the optical depth of airborne dust in the Sahara. On the other hand, the relationships between ω0, τa, and the surface reflectance are less clear in Asia than in the Sahara, and the values of ω0 are smaller than those in the Sahara. The regions with small ω0 values are consistent with the regions where coal-burning smoke and carbonaceous aerosols are thought to be transported, as reported in previous studies. Because the coal-burning and carbonaceous

  2. Diatom-inferred salinity and carbonate oxygen isotopes in Holocene waterbodies of the western Sahara and Sahel (Africa)

    Science.gov (United States)

    Gasse, Françoise

    2002-03-01

    Thirteen Holocene palaeolakes in the western Sahara and Sahel have provided diatom records, with carbonate oxygen isotope profiles available from eight of them. Most of these palaeolakes were groundwater-fed. Lake water chemistry is reconstructed using diatom transfer functions. Lake water salinity and 18O records are assembled with some isotopic and chemical groundwater data to better understand the response of the hydrological systems to climate changes over the past 15,000 yr. Data are in general agreement with climate simulations using coupled atmosphere-ocean-vegetation models which show a mid-Holocene wetting over the whole of northwest Africa, and a rapid drying by 6-4 ka. The lake record also shows that at many sites the major lake infilling lags the end of the Younger Dryas by 1-2 ka. Regional differences also appear in the timing of the lake hydrological optimum: ca. 10.5-8.5 and 7.5-4.5 ka in the northern Sahara, 10-8.5 ka in the Aı̈r-Ténéré, 10-5.7 or 4.5 in the Sahel, and 7.5 ka in Lake Chad. The whole of the Holocene is punctuated by short-term drying events. Changes in water isotopic composition through time are partly explained by changes in rainfall amount and air humidity. During the wet Holocene period however, the very low δ values in the southern Sahara also imply changes in the moisture transport pattern or rainfall mechanisms. Data suggest an apparent decrease in 18O content of precipitation along the monsoon flow, in contrast with modern patterns. Changes in water availability and quality have driven population migrations in and out of the Sahara-Sahel, but relationships between climate and cultures are complex. Short-term dry events might have driven inventive adaptations. In the Sahara, drying at 5-4.5 ka coincides with both the collapse of the classical Neolithic civilization and the settlement of new cultures.

  3. Biophysics and the Challenges of Emerging Threats

    CERN Document Server

    Puglisi, Joseph D

    2009-01-01

    This volume is a collection of articles from the proceedings of the International School of Structural Biology and Magnetic Resonance 8th Course: Biophysics and the Challenges of Emerging Threats. This NATO Advance Study Institute (ASI) was held in Erice at the Ettore Majorana Foundation and Centre for Scientific Culture on 19 through 30 June 2007. The ASI brought together a diverse group of experts who bridged the fields of virology and biology, biophysics, chemistry and physics. Prominent lecturers and students from around the world representant a total of 24 countries participated in the NATO ASI organized by Professors Joseph Puglisi (Stanford University, USA) and Alexander Arseniev (Moscow, RU). The central hypothesis underlying this ASI was that interdisciplinary research, merging principles of physics, chemistry and biology, can drive new discovery in detecting and fighting bioterrorism agents, lead to cleaner environments, and help propel development in NATO partner countries. The ASI merged the relat...

  4. The Convergence of Virtual Reality and Social Networks: Threats to Privacy and Autonomy.

    Science.gov (United States)

    O'Brolcháin, Fiachra; Jacquemard, Tim; Monaghan, David; O'Connor, Noel; Novitzky, Peter; Gordijn, Bert

    2016-02-01

    The rapid evolution of information, communication and entertainment technologies will transform the lives of citizens and ultimately transform society. This paper focuses on ethical issues associated with the likely convergence of virtual realities (VR) and social networks (SNs), hereafter VRSNs. We examine a scenario in which a significant segment of the world's population has a presence in a VRSN. Given the pace of technological development and the popularity of these new forms of social interaction, this scenario is plausible. However, it brings with it ethical problems. Two central ethical issues are addressed: those of privacy and those of autonomy. VRSNs pose threats to both privacy and autonomy. The threats to privacy can be broadly categorized as threats to informational privacy, threats to physical privacy, and threats to associational privacy. Each of these threats is further subdivided. The threats to autonomy can be broadly categorized as threats to freedom, to knowledge and to authenticity. Again, these three threats are divided into subcategories. Having categorized the main threats posed by VRSNs, a number of recommendations are provided so that policy-makers, developers, and users can make the best possible use of VRSNs.

  5. Understanding Cyber Threats and Vulnerabilities

    NARCIS (Netherlands)

    Luiijf, H.A.M.

    2012-01-01

    This chapter reviews current and anticipated cyber-related threats to the Critical Information Infrastructure (CII) and Critical Infrastructures (CI). The potential impact of cyber-terrorism to CII and CI has been coined many times since the term was first coined during the 1980s. Being the relevanc

  6. Threat from Emerging Vectorborne Viruses

    Centers for Disease Control (CDC) Podcasts

    2016-06-09

    Reginald Tucker reads an abridged version of the commentary by CDC author Ronald Rosenberg, Threat from Emerging Vectorborne Viruses.  Created: 6/9/2016 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 6/9/2016.

  7. Cyber Threats to Nuclear Infrastructures

    Energy Technology Data Exchange (ETDEWEB)

    Robert S. Anderson; Paul Moskowitz; Mark Schanfein; Trond Bjornard; Curtis St. Michel

    2010-07-01

    Nuclear facility personnel expend considerable efforts to ensure that their facilities can maintain continuity of operations against both natural and man-made threats. Historically, most attention has been placed on physical security. Recently however, the threat of cyber-related attacks has become a recognized and growing world-wide concern. Much attention has focused on the vulnerability of the electric grid and chemical industries to cyber attacks, in part, because of their use of Supervisory Control and Data Acquisition (SCADA) systems. Lessons learned from work in these sectors indicate that the cyber threat may extend to other critical infrastructures including sites where nuclear and radiological materials are now stored. In this context, this white paper presents a hypothetical scenario by which a determined adversary launches a cyber attack that compromises the physical protection system and results in a reduced security posture at such a site. The compromised security posture might then be malevolently exploited in a variety of ways. The authors conclude that the cyber threat should be carefully considered for all nuclear infrastructures.

  8. The threat of soil salinity

    NARCIS (Netherlands)

    Daliakopoulos, I.N.; Tsanis, I.K.; Koutroulis, A.; Kourgialas, N.N.; Varouchakis, A.E.; Karatzas, G.P.; Ritsema, C.J.

    2016-01-01

    Soil salinisation is one of the major soil degradation threats occurring in Europe. The effects of salinisation can be observed in numerous vital ecological and non-ecological soil functions. Drivers of salinisation can be detected both in the natural and man-made environment, with climate and th

  9. Model Simulations of Complex Dust Emissions over the Sahara during the West African Monsoon Onset

    Directory of Open Access Journals (Sweden)

    Carolina Cavazos-Guerra

    2012-01-01

    Full Text Available The existing limitations in ground-based observations in remote areas in West Africa determine the dependence on numerical models to represent the atmospheric mechanisms that contribute to dust outbreaks at different space-time scales. In this work, the ability of the Weather Research and Forecasting model coupled with the Chemistry (WRF-Chem model using the GOCART dust scheme is evaluated. The period comprises the West African Monsoon onset phase (the 7th to 12th of June, 2006 coinciding with the AMMA Special Observing Period (SOP. Different features in the horizontal and vertical dynamical structure of the Saharan atmosphere are analyzed with a combination of satellite and ground-based observations and model experimentation at 10 and 30 km model resolution. The main features of key Saharan dust processes during summer are identifiable, and WRF-CHEM replicates these adequately. Observations and model analyses have shown that cold pools (haboobs contributed a substantial proportion of total dust during the study period. The comparative analysis between observations and WRF-Chem simulations demonstrates the model efficiency to simulate the spatial and 3D structure of dust transport over the Sahara and Sahel. There is, therefore, a strong basis for accurate forecasting of dust events associated with synoptic scale events when model dust emission parameterization is suitably calibrated.

  10. Satellite imagery and airborne geophysics for geologic mapping of the Edembo area, Eastern Hoggar (Algerian Sahara)

    Science.gov (United States)

    Lamri, Takfarinas; Djemaï, Safouane; Hamoudi, Mohamed; Zoheir, Basem; Bendaoud, Abderrahmane; Ouzegane, Khadidja; Amara, Massinissa

    2016-03-01

    Satellite imagery combined with airborne geophysical data and field observations were employed for new geologic mapping of the Edembo area in the Eastern Hoggar (Tuareg Shield, Sahara). Multi-spectral band fusion, filtering, and transformation techniques, i.e., band combination, band-rationing and principal component analysis of ETM+ and ASTER data are used for better spectral discrimination of the different rocks units. A thematic map assessed by field data and available geologic information is compiled by supervised classification of satellite data with high overall accuracy (>90%). The automated extraction technique efficiently aided the detection of the structural lineaments, i.e., faults, shear zones, and joints. Airborne magnetic and Gamma-ray spectrometry data showed the pervasiveness of the large structures beneath the Paleozoic sedimentary cover and aeolian sands. The aeroradiometric K-range is used for discrimination of the high-K granitoids of Djanet from the peralumineous granites of Edembo, and to verify the Silurian sediments with their high K-bearing minerals. The new geological map is considered to be a high resolution improvement on all pre-existing maps of this hardly accessible area in the Tuareg Shield. Integration of the airborne geophysical and space-borne imagery data can hence provide a rapid means of geologically mapping areas hitherto poorly known or difficult to access.

  11. The Right to Self-Determination and Natural Resources: The Case of Western Sahara

    Directory of Open Access Journals (Sweden)

    Hans Morten Haugen

    2007-06-01

    Full Text Available Phosphate, fish and possibly oil and gas all constitute important natural resources found on the territory and in the waters of Western Sahara. The importance of these natural resources must be recognised in order to understand the stalemate in the attempted process of decolonisation from Morocco which has been going on for more than 30 years. The article analyses the ‘resource dimension’ of the right to self-determination, as recognised in human rights treaties and in Resolution III of the UN Conference on the Law of the Seas, as well as several resolutions from the United Nations General Assembly. If the resources are exploited in a manner which does not benefit the peoples seeking to enjoy the right to self-determination, such exploitation is illegal. The article shows that the current exploitation takes place in a manner contrary to the interests of the local population, the Saharawis. The article also demonstrates that recent license agreements with Saharawi authorities in the field of oil and gas, signal a potentially new and constructive approach by international corporations.

  12. Dynamics of green Sahara periods and their role in hominin evolution.

    Science.gov (United States)

    Larrasoaña, Juan C; Roberts, Andrew P; Rohling, Eelco J

    2013-01-01

    Astronomically forced insolation changes have driven monsoon dynamics and recurrent humid episodes in North Africa, resulting in green Sahara Periods (GSPs) with savannah expansion throughout most of the desert. Despite their potential for expanding the area of prime hominin habitats and favouring out-of-Africa dispersals, GSPs have not been incorporated into the narrative of hominin evolution due to poor knowledge of their timing, dynamics and landscape composition at evolutionary timescales. We present a compilation of continental and marine paleoenvironmental records from within and around North Africa, which enables identification of over 230 GSPs within the last 8 million years. By combining the main climatological determinants of woody cover in tropical Africa with paleoenvironmental and paleoclimatic data for representative (Holocene and Eemian) GSPs, we estimate precipitation regimes and habitat distributions during GSPs. Their chronology is consistent with the ages of Saharan archeological and fossil hominin sites. Each GSP took 2-3 kyr to develop, peaked over 4-8 kyr, biogeographically connected the African tropics to African and Eurasian mid latitudes, and ended within 2-3 kyr, which resulted in rapid habitat fragmentation. We argue that the well-dated succession of GSPs presented here may have played an important role in migration and evolution of hominins.

  13. SHUTTLE IMAGING RADAR: PHYSICAL CONTROLS ON SIGNAL PENETRATION AND SUBSURFACE SCATTERING IN THE EASTERN SAHARA.

    Science.gov (United States)

    Schaber, Gerald G.; McCauley, John F.; Breed, Carol S.; Olhoeft, Gary R.

    1986-01-01

    It is found that the Shuttle Imaging Radar A (SIR-A) signal penetration and subsurface backscatter within the upper meter or so of the sediment blanket in the Eastern Sahara of southern Egypt and northern Sudan are enhanced both by radar sensor parameters and by the physical and chemical characteristics of eolian and alluvial materials. The near-surface stratigraphy, the electrical properties of materials, and the types of radar interfaces found to be responsible for different classes of SIR-A tonal response are summarized. The dominant factors related to efficient microwave signal penetration into the sediment blanket include 1) favorable distribution of particle sizes, 2) extremely low moisture content and 3) reduced geometric scattering at the SIR-A frequency (1. 3 GHz). The depth of signal penetration that results in a recorded backscatter, called radar imaging depth, was documented in the field to be a maximum of 1. 5 m, or 0. 25 times the calculated skin depth, for the sediment blanket. The radar imaging depth is estimated to be between 2 and 3 m for active sand dune materials.

  14. Dental indicators of adaptation in the Sahara Desert during the Late Holocene.

    Science.gov (United States)

    Nikita, E; Mattingly, D; Lahr, M M

    2014-10-01

    The present paper examines dental diseases and linear enamel hypoplasia among the Garamantes, a Late Holocene Saharan population, and aims to draw conclusions about nutrition and adaptation to a hyper-arid environment. Archaeological evidence suggests that the Garamantian diet included animal protein and local, Mediterranean and Near Eastern plants. Moreoever, although the Garamantes had developed urban centres, the size of these was not large enough to allow for particularly unhygienic conditions to appear. The above archaeological findings were partly corroborated by the current bioarchaeological study. At an intra-population level, the Garamantes showed limited sex differences in dental disease prevalence, while all dental conditions increased in frequency with age, as expected. At an inter-population level, the frequency of all dental conditions was comparable to that found among other North African groups, with the exception of ante-mortem tooth loss. The low frequency of most dental conditions is an indication that the Garamantian diet was overall balanced, while the high frequency of ante-mortem tooth loss may be related to factors such as oral hygiene, food preparation or eating mode, which cannot be controlled for osteologically. Finally, the low frequency of enamel hypoplasia suggests either that the Sahara did not inflict particular stresses on the population, or, more likely, that the Garamantes had developed effective mechanisms for coping with their natural environment.

  15. Characterization and antimicrobial potential of extremely halophilic archaea isolated from hypersaline environments of the Algerian Sahara.

    Science.gov (United States)

    Quadri, Inès; Hassani, Imene Ikrame; l'Haridon, Stéphane; Chalopin, Morgane; Hacène, Hocine; Jebbar, Mohamed

    2016-01-01

    Halophilic archaea were isolated from different chotts and sebkha, dry salt lakes and salt flat respectively, of the Algerian Sahara and characterized using phenotypic and phylogenetic approaches. From 102 extremely halophilic strains isolated, forty three were selected and studied. These strains were also screened for their antagonistic potential and the production of hydrolytic enzymes. Sequencing of the 16S rRNA genes and phylogenetic analysis allowed the identification of 10 archaeal genera within the class Halobacteria: Natrinema (13 strains), Natrialba (12 strains), Haloarcula (4 strains), Halopiger (4 strains), Haloterrigena (3 strains), Halorubrum (2 strains), Halostagnicola (2 strains), Natronococcus, Halogeometricum and Haloferax (1 strain each). The most common producers of antimicrobial compounds belong to the genus Natrinema while the most hydrolytic isolates, with combined production of several enzymes, belong to the genus Natrialba. The strain affiliated to Halopiger djelfamassilliensis was found to produce some substances of interest (halocins, anti-Candida, enzymes). After partial purification and characterization of one of the strains Natrinema gari QI1, we found similarities between the antimicrobial compound and the halocin C8. Therefore, the gene encoding halocin C8 was amplified and sequenced.

  16. Globalisation of water: Opportunities and threats of virtual water trade

    OpenAIRE

    Chapagain, A.K.

    2006-01-01

    Where the river basin is generally seen as the appropriate unit for analyzing freshwater availability and use, it becomes increasingly important to put freshwater issues in a global context. The book analyses the opportunities and threats of international virtual water trade in the context of solving national and regional problems of water shortages. Central questions addressed in the study are: What are the fluxes of virtual water related to the international trade of products? Is the import...

  17. Is China Threat a Hoax?

    Institute of Scientific and Technical Information of China (English)

    Niu Weigan; Ma Zongshi

    2008-01-01

    The Beijing Olympics has focused unprecedented world attention on China this year. Many people hail the Games as an occasion that showcases China's growing contribution to world development and harmony. But intent on politicizing this global event, a few modern Cassandras still cling to the flawed China Threat theory. In this paper, the author traces the origins of this fallacious theory. He sees it as a product of Western empiricism viewed through an historical and philosophical prism. He argues that the assertion of threat arises from a generalization of historical facts. The assertion links China's growing clout with declining Western dominance in international affairs. Starting with the myth that peace is possible only among democracies, the theory predicts the inevitability of conflict between the West and China, a country with an alleged expansionist tradition and under an authoritarian system.

  18. Zika Still a Threat During Winter Months

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_162518.html Zika Still a Threat During Winter Months Public health ... doesn't necessarily mean the end of the Zika threat in the United States, a public health ...

  19. Filling in biodiversity threat gaps

    DEFF Research Database (Denmark)

    Joppa, L. N.; O'Connor, Brian; Visconti, Piero

    2016-01-01

    increase to 10,000 times the background rate should species threatened with extinction succumb to pressures they face (4). Reversing these trends is a focus of the Convention on Biological Diversity's 2020 Strategic Plan for Biodiversity and its 20 Aichi Targets and is explicitly incorporated...... into the United Nations' 2030 Agenda for Sustainable Development and its 17 Sustainable Development Goals (SDGs). We identify major gaps in data available for assessing global biodiversity threats and suggest mechanisms for closing them....

  20. Subordinates as Threats to Leaders

    OpenAIRE

    Glazer, Amihai; Segendorff, Björn

    2001-01-01

    A leader of an organization may view a subordinate as threatening or weakening the leader's position. The threat may increase with the subordinate's ability and reduce the rents the leader wins. In particular, a leader who trains his subordinate reduces the cost to the owner of a firm in replacing the leader, and so reduces the leader's bargaining power. The leader therefore provides inefficiently low training for the subordinate.

  1. Cyber Terrorism– Global Security Threat

    OpenAIRE

    Bogdanoski, Mitko; Petreski, Drage

    2013-01-01

    It is more than obvious that the way of conducting terrorism with the time is becoming more sophisticated. The cyber terrorism is real threat to fast technology development. Potential targets are systems which control the nation’s defenses and critical infrastructure. The terrorist of the future will win the wars without firing a shot - just by destroying infrastructure that significantly relies on information technology. The fast growth of the Internet users and Internet dependence dramat...

  2. OBESITY AMONG SCHOOL CHILDREN: AN EMERGING THREAT IN CENTRAL INDIA

    Directory of Open Access Journals (Sweden)

    Garima

    2014-09-01

    Full Text Available BACKGROUND: Obesity in children and adolescents is rapidly reaching epidemic proportions globally as well as in India. It is a well-recognized risk factor for adult obesity, which in turn may be the basis of various chronic diseases. So, by preventing the development of obesity in childhood can reduce the likelihood of obesity in adulthood and its health consequences. AIMS & OBJECTIVES: To find out the prevalence of overweight and obesity among school children in Bhopal city. MATERIAL & METHODS: STUDY DESIGN: Cross sectional descriptive study. STUDY POPULATION: Students studying in IX, X, XI, XII class in government and private schools of Bhopal STUDY PERIOD: July 2012-June 2014 (24 Months SAMPLING PROCEDURE: Multistage simple random sampling method was used to select schools from a list obtained by Ministry of education. Total 38 schools were chosen to fulfill the sample size, in which 120 students from each school were included under study. METHODS OF DATA COLLECTION: Data was collected by taking anthropometric measurements like body weight, height, BMI (Body mass index, WC (waist circumference. RESULTS: In present study, 256 (5.6% students were overweight and 46 (1.0% were obese. Total 2505 (55.0% of students have waist circumferences between 70 to 85 cm, whereas only 187(4.0% students have waist circumference more than 85 cm. CONCLUSION: The overall prevalence of overweight and obesity was 5.6% and 1.0% respectively among school children. It was more common in girls and among students of private schools.

  3. Children's environment in Central Europe: threats and chances.

    Science.gov (United States)

    Böse-O'Reilly, Stephan; Heudorf, Ursel; Lob-Corzilius, Thomas; von Mühlendahl, Karl Ernst; Otto, Matthias; Schmidt, Sabine

    2007-10-01

    Many of the "classical" environmental hazards and risks (such as anthropogenic chemical and physical factors, e.g., asbestos, dioxin, electromagnetic fields and "pesticides") are in our countries not major determinants of children's health and well being; however, there may exist unseen or unrecognized causal contexts. Some hazards, such as UV light, noise, fine particles, tobacco smoke, legal and illegal drugs, and radon, are considered important by experts, but are still largely ignored by the public. In our society, despite of, or maybe because of the multitude of information and disinformation, adequate risk perception continues to be a problem. Furthermore, ever-new environmental toxicants will come to the surface and occupy medial interest, and thus, continuing attention is warranted. Of our children's environment, yet other facets are of prime importance: nutrition, housing and traffic and public media. Most important, however, is the fact that society (governments, administration, industry and consumers) are disregarding the long-term sustainability of their actions and behaviour, thus endangering the future of our children and grandchildren. This is in contrast with the existing declarations and official action plans. In future, ranking of priorities for research and actions will be necessary, taking into account costs and effectiveness since resources to be invested into these issues certainly will remain limited.

  4. Sahara dust, ocean spray, volcanoes, biomass burning: pathways of nutrients into Andean rainforests

    Directory of Open Access Journals (Sweden)

    P. Fabian

    2009-10-01

    Full Text Available Regular rain and fogwater sampling in the Podocarpus National Park, on the humid eastern slopes of the Ecuadorian Andes, along an altitude profile between 1960 and 3180 m, has been carried out since 2002. The samples, accumulated over about 1-week intervals, were analysed for pH, conductivity and major ions (K+, Na+, NH4+, Ca2+, Mg2+, Cl, SO42−, NO3, PO43−.

    About 35% of the weekly samples had very low ion contents, with pH mostly above 5 and conductivity below 10 μS/cm. 10-days back trajectories (FLEXTRA showed that respective air masses originated in pristine continental areas, with little or no obvious pollution sources.

    About 65%, however, were significantly loaded with cations and anions, with pH as low as 3.5 to 4.0 and conductivity up to 50 μS/cm. The corresponding back trajectories clearly showed that air masses had passed over areas of intense biomass burning, active volcanoes, and the ocean, with episodic Sahara and/or Namib desert dust interference.

    Enhanced SO42− and NO3+ were identified, by combining satellite-based fire pixel observations with back trajectories, as predominantly resulting from biomass burning. Analyses of oxygen isotopes 16O, 17O, and 18O in nitrate show that nitrate in the samples is indeed a product of atmospheric conversion of precursors. Some SO42−, about 10% of the total input, could be identified to originate from active volcanoes, whose plumes were encountered by about 10% of all trajectories.

    Enhanced Na+, K+, and Cl were found to originate from ocean spray sources. They were associated with winds providing Atlantic air masses to the receptor site within less than 5 days. Episodes of

  5. Advances in understanding mineral dust and boundary layer processes over the Sahara from Fennec aircraft observations

    Directory of Open Access Journals (Sweden)

    C. L. Ryder

    2015-01-01

    Full Text Available The Fennec climate program aims to improve understanding of the Saharan climate system through a synergy of observations and modelling. We present a description of the Fennec airborne observations during 2011 and 2012 over the remote Sahara (Mauritania and Mali and the advances in the understanding of mineral dust and boundary layer processes they have provided. Aircraft instrumentation aboard the UK FAAM BAe146 and French SAFIRE Falcon 20 is described, with specific focus on instrumentation specially developed and relevant to Saharan meteorology and dust. Flight locations, aims and associated meteorology are described. Examples and applications of aircraft measurements from the Fennec flights are presented, highlighting new scientific results delivered using a synergy of different instruments and aircraft. These include: (1 the first airborne measurement of dust particles sized up to 300 microns and associated dust fluxes in the Saharan atmospheric boundary layer (SABL, (2 dust uplift from the breakdown of the nocturnal low-level jet before becoming visible in SEVIRI satellite imagery, (3 vertical profiles of the unique vertical structure of turbulent fluxes in the SABL, (4 in-situ observations of processes in SABL clouds showing dust acting as CCN and IN at −15 °C, (5 dual-aircraft observations of the SABL dynamics, thermodynamics and composition in the Saharan heat low region (SHL, (6 airborne observations of a dust storm associated with a cold-pool (haboob issued from deep convection over the Atlas, (7 the first airborne chemical composition measurements of dust in the SHL region with differing composition, sources (determined using Lagrangian backward trajectory calculations and absorption properties between 2011 and 2012, (8 coincident ozone and dust surface area measurements suggest coarser particles provide a route for ozone depletion, (9 discrepancies between airborne coarse mode size distributions and AERONET sunphotometer

  6. Actinopolyspora biskrensis sp. nov., a novel halophilic actinomycete isolated from Northern Sahara.

    Science.gov (United States)

    Saker, Rafika; Bouras, Noureddine; Meklat, Atika; Zitouni, Abdelghani; Schumann, Peter; Spröer, Cathrin; Klenk, Hans-Peter; Sabaou, Nasserdine

    2015-03-01

    A novel halophilic, filamentous actinomycete, designated H254(T), was isolated from a Saharan soil sample collected from Biskra (Northern Sahara), and subjected to a polyphasic taxonomic characterization. The strain is Gram-positive, aerobic, and halophilic, and the optimum NaCl concentration for growth is 15-20 % (w/v). The cell-wall hydrolysate contained meso-diaminopimelic acid, and the diagnostic whole-cell sugars were arabinose and galactose. The diagnostic phospholipid detected was phosphatidylcholine, and MK-9(H4) was the predominant menaquinone. The major fatty acid profiles were anteiso-C17:0 (32.8 %), C15:0 (28 %), and iso-C17:0 (12.3 %). Comparative analysis of the 16S rRNA gene sequences revealed that the strain H254(T) formed a well-separated sub-branch within the radiation of the genus Actinopolyspora, and the microorganism was most closely related to Actinopolyspora saharensis DSM 45459(T) (99.2 %), Actinopolyspora halophila DSM 43834(T) (99.1 %), and Actinopolyspora algeriensis DSM 45476(T) (99.0 %). Nevertheless, the strain had relatively lower mean values for DNA-DNA relatedness with the above strains (57.2, 68.4, and 45.6 %, respectively). Based on phenotypic features and phylogenetic position, we propose that strain H254(T) represents a novel species of the genus Actinopolyspora, for which the name Actinopolyspora biskrensis sp. nov. is proposed. The type strain of A. biskrensis is strain H254(T) (=DSM 46684(T) =CECT 8576(T)).

  7. Alliance of proteomics and genomics to unravel the specificities of Sahara bacterium Deinococcus deserti.

    Directory of Open Access Journals (Sweden)

    Arjan de Groot

    2009-03-01

    Full Text Available To better understand adaptation to harsh conditions encountered in hot arid deserts, we report the first complete genome sequence and proteome analysis of a bacterium, Deinococcus deserti VCD115, isolated from Sahara surface sand. Its genome consists of a 2.8-Mb chromosome and three large plasmids of 324 kb, 314 kb, and 396 kb. Accurate primary genome annotation of its 3,455 genes was guided by extensive proteome shotgun analysis. From the large corpus of MS/MS spectra recorded, 1,348 proteins were uncovered and semiquantified by spectral counting. Among the highly detected proteins are several orphans and Deinococcus-specific proteins of unknown function. The alliance of proteomics and genomics high-throughput techniques allowed identification of 15 unpredicted genes and, surprisingly, reversal of incorrectly predicted orientation of 11 genes. Reversal of orientation of two Deinococcus-specific radiation-induced genes, ddrC and ddrH, and identification in D. deserti of supplementary genes involved in manganese import extend our knowledge of the radiotolerance toolbox of Deinococcaceae. Additional genes involved in nutrient import and in DNA repair (i.e., two extra recA, three translesion DNA polymerases, a photolyase were also identified and found to be expressed under standard growth conditions, and, for these DNA repair genes, after exposure of the cells to UV. The supplementary nutrient import and DNA repair genes are likely important for survival and adaptation of D. deserti to its nutrient-poor, dry, and UV-exposed extreme environment.

  8. A forest butterfly in sahara desert oases: isolation does not matter.

    Science.gov (United States)

    Habel, Jan Christian; Husemann, Martin; Schmitt, Thomas; Dapporto, Leonardo; Rödder, Dennis; Vandewoestijne, Sofie

    2013-03-01

    Numerous studies addressing the impact of habitat fragmentation on genetic diversity have been performed. In this study, we analyze the effects of a seemingly nonpermeable matrix on the population structure of the forest-dwelling butterfly Pararge aegeria in geographically isolated oases at the northern margin of the Sahara desert using microsatellites, morphological characters, and species distribution modeling. Results from all analyses are mostly congruent and reveal 1) a split between European and North African populations, 2) rather low divergence between populations from the eastern and western part of North Africa (Morocco vs. Tunisia), 3) a lack of differentiation between the oasis and Atlas Mountain populations, 4) as well as among the oasis populations, and 5) no reduction of genetic variability in oasis populations. However, one exception to this general trend resulted from the analyses of wing shape; wings of butterflies from oases are more elongated compared with those from the other habitats. This pattern of phenotypic divergence may suggest a recent colonization of the oasis habitats by individuals, which might be accompanied by a rather dispersive behavior. Species distribution modeling suggests a fairly recent reexpansion of the species' climatic niche starting in the Holocene at about 6000 before present. The combined results indicate a rather recent colonization of the oases by highly mobile individuals from genetically diverse founder populations. The colonization was likely followed by the expansion and persistence of these founder populations under relatively stable environmental conditions. This, together with low rates of gene flow, likely prevented differentiation of populations via drift and led to the maintenance of high genetic diversity.

  9. Stereotype Threat, Test Anxiety, and Mathematics Performance

    Science.gov (United States)

    Tempel, Tobias; Neumann, Roland

    2014-01-01

    We investigated the combined effects of stereotype threat and trait test anxiety on mathematics test performance. Stereotype threat and test anxiety interacted with each other in affecting performance. Trait test anxiety predicted performance only in a diagnostic condition that prevented stereotype threat by stereotype denial. A state measure of…

  10. A new cichlid fish in the Sahara: The Ounianga Serir lakes (Chad), a biodiversity hotspot in the desert.

    Science.gov (United States)

    Trape, Sébastien

    In the rare perennial bodies of water of the Sahara desert, only a few fish species have survived to increasing aridification since the end of the last humid period at the Holocene, approximately 5000 years BP. Here, I report the occurrence of an undescribed haplochomine cichlid fish in Lake Boukou, one of the seven Ounianga Serir lakes (Chad). These lakes are located in one of the most arid areas of the Sahara desert, but they persist by virtue of subsurface inflow of fresh groundwater from a large fossil aquifer. Astatotilapia tchadensis sp. nov. is characterized by a black bar between eye and corner of mouth, rounded orange spots on anal fin, scales ctenoid, lower limb of first gill arch with 7-8 gill rackers, dorsal fin with 13-14 spines and 9-11 soft rays, anal fin with 3 spines and 8-9 soft rays, 29 or 30 lateral line scales, and lower pharyngeal dentition with enlarged molariform teeth. The new species is easily distinguished from A. desfontainii and A. flaviijosephii, the northernmost haplochromine species currently isolated from its other group members, and appears close to an unnamed species of Lake Chad basin. Ounianga Serir lakes and especially Lake Boukou present a remarkable diversity of fish, the highest known in the Sahara desert with a total of at least six fish species belonging to six genera and three families. They also constitute an exceptional natural landscape inscribed on the UNESCO world heritage list in 2012 and a biodiversity hotspot for desert vertebrate species.

  11. Role of surface wind and vegetation cover in multi-decadal variations of dust emission in the Sahara and Sahel

    Science.gov (United States)

    Kim, Dongchul; Chin, Mian; Remer, Lorraine A.; Diehl, Thomas; Bian, Huisheng; Yu, Hongbin; Brown, Molly E.; Stockwell, William R.

    2017-01-01

    North Africa, the world's largest dust source, is non-uniform, consisting of a permanently arid region (Sahara), a semi-arid region (Sahel), and a relatively moist vegetated region (Savanna), each with very different rainfall patterns and surface conditions. This study aims to better understand the controlling factors that determine the variation of dust emission in North Africa over a 27-year period from 1982 to 2008, using observational data and model simulations. The results show that the model-derived Saharan dust emission is only correlated with the 10-m winds (W10m) obtained from reanalysis data, but the model-derived Sahel dust emission is correlated with both W10m and the Normalized Difference Vegetation Index (NDVI) that is obtained from satellite. While the Saharan dust accounts for 82% of the continental North Africa dust emission (1340-1570 Tg year-1) in the 27-year average, the Sahel accounts for 17% with a larger seasonal and inter-annual variation (230-380 Tg year-1), contributing about a quarter of the transatlantic dust transported to the northern part of South America. The decreasing dust emission trend over the 27-year period is highly correlated with W10m over the Sahara (R = 0.92). Over the Sahel, the dust emission is correlated with W10m (R = 0.69) but is also anti-correlated with the trend of NDVI (R = -0.65). W10m is decreasing over both the Sahara and the Sahel between 1982 and 2008, and the trends are correlated (R = 0.53), suggesting that Saharan/Sahelian surface winds are a coupled system, driving the inter-annual variation of dust emission.

  12. Stereotype threat and female communication styles.

    Science.gov (United States)

    von Hippel, Courtney; Wiryakusuma, Cindy; Bowden, Jessica; Shochet, Megan

    2011-10-01

    A large body of research has documented the performance-debilitating effects of stereotype threat for individuals, but there is a paucity of research exploring interpersonal consequences of stereotype threat. Two experiments tested the hypothesis that stereotype threat would change the style in which women communicate. Results indicate that women who experience stereotype threat regarding leadership abilities react against the stereotype by adopting a more masculine communication style. Study 2 provides evidence that self-affirmation eliminates this effect of stereotype threat on women's communication styles. A third study demonstrates an ironic consequence of this effect of stereotype threat on women's communication--when women under stereotype threat adopt a more masculine communication style, they are rated as less warm and likeable, and evaluators indicate less willingness to comply with their requests. Theoretical and practical implications of these findings are discussed.

  13. Wireless LAN Security Threats & Vulnerabilities

    Directory of Open Access Journals (Sweden)

    Md. Waliullah

    2014-01-01

    Full Text Available Wireless LANs are everywhere these days from home to large enterprise corporate networks due to the ease of installation, employee convenience, avoiding wiring cost and constant mobility support. However, the greater availability of wireless LANs means increased danger from attacks and increased challenges to an organisation, IT staff and IT security professionals. This paper discusses the various security issues and vulnerabilities related to the IEEE 802.11 Wireless LAN encryption standard and common threats/attacks pertaining to the home and enterprise Wireless LAN system and provide overall guidelines and recommendation to the home users and organizations.

  14. Symbian `vulnerability' and Mobile Threats

    CERN Document Server

    Gharibi, Wajeb

    2012-01-01

    Modern technologies are becoming ever more integrated with each other. Mobile phones are becoming increasing intelligent, and handsets are growing ever more like computers in functionality. We are entering a new era - the age of smart houses, global advanced networks which encompass a wide range of devices, all of them exchanging data with each other. Such trends clearly open new horizons to malicious users, and the potential threats are self evident. In this paper, we study and discuss one of the most famous mobile operating systems 'Symbian'; its vulnerabilities and recommended protection technologies.

  15. New Threat to World Economy

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The aggregate amount of money and credit in the global economy has risen sharply over the past 30 years,with its growth rate and stock far exceeding that of the real economy or real assets of the world.This is the view of Xiang Songzuo,professor at the Huazhong University of Science and Technology,whose opinion was first published in a recent article in China Business News.Xiang said this situation is a real threat to the world economy.Excerpts of his article are reprinted below:

  16. Threat, security and attitude formation among the young

    Science.gov (United States)

    Radin, Furio

    1985-12-01

    The perception of threat to security on the part of young people reflects a central aspect of the societal phenomenon of attitude formation, whose primary function is, ideally, to meet the need for security. In all modern societies, however, the process of socialization — which by its very nature is educational in that it prepares individuals to function as members of society — operates on the principle of systematically frustrating this need by employing a system of reward and punishment based on competition. This system creates a fundamental insecurity and a corresponding attitude (de)formation in the individual, which is exploited by the state in order to consolidate the power of the dominant groups. Due to this fundamental insecurity, the individual is incapable of coping rationally with threat and seeks pseudo-security, e.g., in conformity. Threat — particularly global threat — is perceived as an external factor over which the individual has no control, i.e., it is perceived as falling exclusively within the province of those in power, whose control is further strengthened by this perception. Since the essential damage to the individual's attitude system has been done by the time he leaves school, this undesirable condition of modern societies can only be rectified by a socialization process in general — and an educational process in particular — which cultivates in the individual the development of critical judgment, free self-realization and the spirit of co-operation instead of competition.

  17. The Role of Meteorology and Surface Condition to Multi-Decadal Variations of Dust Emission in Sahara and Sahel

    Science.gov (United States)

    Kim, D.; Chin, M.; Diehl, T. L.; Bian, H.; Brown, M. E.; Remer, L. A.; Stockwell, W. R.

    2014-12-01

    North Africa is the world's largest dust source region influencing regional and global climate, human health, and even the local economy. However North Africa as a dust source is not uniform but it consists of the arid region (Sahara) and the semi-arid region (Sahel) with emission rates depending on meteorological and surface conditions. Several recent studies have shown that dust from North Africa seems to have a decreasing trend in the past three decades. The goal of this study is to better understand the controlling factors that determine the change of dust in North Africa using observational data and model simulations. First we analyze surface bareness conditions determined from a long-term satellite observed Normalized Difference Vegetation Index for 1980-2008. Then we examine the key meteorological variables of precipitation and surface winds. Modeling experiments were conducted using the NASA Goddard Chemistry Aerosol Radiation and Transport (GOCART) model, which has been recently updated with a dynamic dust source function. Using the method we separate the dust originating from the Sahel from that of the Sahara desert. We find that the surface wind speed is the most dominant factor affecting Sahelian dust emission while vegetation has a modulating effect. We will show regional differences in meteorological variables, surface conditions, dust emission, and dust distribution and address the relationships among meteorology, surface conditions, and dust emission/loading in the past three decades (1980-2008).

  18. Presence and Origin of Fluoride in the Complex Terminal Water of Ouargla Basin (Northern Sahara of Algeria

    Directory of Open Access Journals (Sweden)

    Imed E. Nezli

    2009-01-01

    Full Text Available Problem statement: The underground waters in the oriental regions of the Algerian Sahara, present real chemical quality problems. Their content in fluorides always exceeds the limit of the recommended levels. That is 0.8 mg L-1, according to the maximum temperature in the region. Combined to a high salinity, it affects the health of the population living around the region. The present work, deals with the presence of fluoride and the geochemical origin in the Complex Terminal aquifer of Ouargla, rarely examined in the Algerian Sahara. Approach: Is based on the following aspects: Sampling and physico-chemicals analysis of water, statistical treatment of the physico-chemical water parameters and simulation to natural and isotherm 25°C evaporation of water parameters. Results: The results show the presence of fluoride in the studied water. The rates vary between 1 and 2 mg L-1. The calculation of water saturation index in relation with the preponderant minerals, using the thermodynamic model ‹‹phreeqci›› reveals a sensitivity of carbonate minerals towards precipitation and dissolution of evaporitic minerals and clayey fluorides as well. Conclusions/Recommendations: The increasing alkalinity of water in contact with the aquifer during long periods of stay decreases the chemical activity of calcium and helps with alteration of clayey minerals and fluoride as a necessary condition for a possible fluorite mineralization. Knowing the origin of that fluoridation leads to possible solutions, through the optimization of a water treatment meets the standards.

  19. Constraining the Sahara freshwater discharge during sapropel S5 time by a stable isotope record from the Greater Sirte

    Science.gov (United States)

    Zirks, Eleen; Kucera, Michal; Bachem, Paul; Schulz, Hartmut

    2016-04-01

    The Nile River and the Black Sea were long considered as the only significant eastern Mediterranean freshwater sources and therefore inferred as the primary agents promoting surface stratification associated with sapropel formation. Sapropel S5, deposited during the last interglacial, marks a time of possible movement of Homo sapiens out of Africa. Satellite images revealed the existence of ancient rivers that once ran through the Sahara desert and drained into the Gulf of Sirte. Anomalous Nd isotope records from sapropel S5 deposits indicate that these rivers may have been active during MIS 5e, implying another freshwater source into the eastern Mediterranean Sea during that period. To constrain the extent of freshwater discharge into the Mediterranean from the Kufrah River during MIS 5e, a new δ18O record of five planktonic foraminifera species was generated from sediment core GeoTü SL 96, located proximal to the assumed outflow of the Kufrah River. The record from core GeoTü SL 96 compared with seven other records from the eastern Mediterranean Sea reveal a pattern of oxygen isotope anomalies which implies that the Kufrah River delivered detectable amount of freshwater during the second part of sapropel S5. These results reinforce the hypothesis that Sahara river systems were active during MIS 5e, which has ramifications for the understanding of sapropel events, reconstruction of coastal landscape, and the better understanding of migration routes of early humans.

  20. Impacts of dust reduction on the northward expansion of the African monsoon during the Green Sahara period

    Science.gov (United States)

    Pausata, Francesco S. R.; Messori, Gabriele; Zhang, Qiong

    2016-01-01

    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 West African Monsoon (WAM) occurred between 15000-5000 yr BP, when increased summer rainfall led to the so-called "Green Sahara" and to a reduction in dust emissions from the region. However, model experiments are unable to fully reproduce the intensification and geographical expansion of the WAM during this period, even when vegetation over the Sahara is considered. Here, we use a fully coupled simulation for 6000 yr BP (Mid-Holocene) in which prescribed Saharan vegetation and dust concentrations are changed in turn. A closer agreement with proxy records is obtained only when both the Saharan vegetation changes and dust decrease are taken into account. The dust reduction strengthens the vegetation-albedo feedback, extending the monsoon's northern limit approximately 500 km further than the vegetation-change case only. We therefore conclude that accounting for changes in Saharan dust loadings is essential for improving model simulations of the WAM during the Mid-Holocene.

  1. Psychobiological responses to social threat: evolution of a psychological model in psychoneuroimmunology.

    Science.gov (United States)

    Kemeny, Margaret E

    2009-01-01

    There exists a bidirectional network of interactions between the central nervous system, the endocrine system and the immune system. The existence of these pathways allows stressful life experience to impact the immune system with important implications for health. One powerful elicitor of changes in the autonomic, endocrine and immune systems is threat to social status. This review describes the development of a human model of social status threat that specifies a set of contextual, psychological and biological pathways that may underlie the health consequences of threats to social status and regard. The role of cognitive processes in shaping the physiological response to the social world will be emphasized.

  2. Advances in understanding mineral dust and boundary layer processes over the Sahara from Fennec aircraft observations

    Science.gov (United States)

    Ryder, C. L.; McQuaid, J. B.; Flamant, C.; Rosenberg, P. D.; Washington, R.; Brindley, H. E.; Highwood, E. J.; Marsham, J. H.; Parker, D. J.; Todd, M. C.; Banks, J. R.; Brooke, J. K.; Engelstaedter, S.; Estelles, V.; Formenti, P.; Garcia-Carreras, L.; Kocha, C.; Marenco, F.; Sodemann, H.; Allen, C. J. T.; Bourdon, A.; Bart, M.; Cavazos-Guerra, C.; Chevaillier, S.; Crosier, J.; Darbyshire, E.; Dean, A. R.; Dorsey, J. R.; Kent, J.; O'Sullivan, D.; Schepanski, K.; Szpek, K.; Trembath, J.; Woolley, A.

    2015-07-01

    The Fennec climate programme aims to improve understanding of the Saharan climate system through a synergy of observations and modelling. We present a description of the Fennec airborne observations during 2011 and 2012 over the remote Sahara (Mauritania and Mali) and the advances in the understanding of mineral dust and boundary layer processes they have provided. Aircraft instrumentation aboard the UK FAAM BAe146 and French SAFIRE (Service des Avions Français Instrumentés pour la Recherche en Environnement) Falcon 20 is described, with specific focus on instrumentation specially developed for and relevant to Saharan meteorology and dust. Flight locations, aims and associated meteorology are described. Examples and applications of aircraft measurements from the Fennec flights are presented, highlighting new scientific results delivered using a synergy of different instruments and aircraft. These include (1) the first airborne measurement of dust particles sizes of up to 300 microns and associated dust fluxes in the Saharan atmospheric boundary layer (SABL), (2) dust uplift from the breakdown of the nocturnal low-level jet before becoming visible in SEVIRI (Spinning Enhanced Visible Infra-Red Imager) satellite imagery, (3) vertical profiles of the unique vertical structure of turbulent fluxes in the SABL, (4) in situ observations of processes in SABL clouds showing dust acting as cloud condensation nuclei (CCN) and ice nuclei (IN) at -15 °C, (5) dual-aircraft observations of the SABL dynamics, thermodynamics and composition in the Saharan heat low region (SHL), (6) airborne observations of a dust storm associated with a cold pool (haboob) issued from deep convection over the Atlas Mountains, (7) the first airborne chemical composition measurements of dust in the SHL region with differing composition, sources (determined using Lagrangian backward trajectory calculations) and absorption properties between 2011 and 2012, (8) coincident ozone and dust surface area

  3. The place of sub-Sahara Africa in the world sport system

    Directory of Open Access Journals (Sweden)

    T. Dejonghe

    2001-01-01

    Full Text Available The contemporary world sportsystem is developed through globalisation with its homogenisation and heterogenisation processes. The result of these opposite forces is the division of the world in 6 classes. Sub-Sahara Africa underwent, with the exception of South-Africa, Namibia and Zimbabwe, a total and passive acceptance of the western (British modern sports. The place of that part of Africa is analogue to and correlates with its place in Wallerstein's world-system periphery. The introduction of modern sports is associated with the spatial diffusion of the 19th century British hegemonic cultural imperialism. The purpose of this policy was a transformation of the traditional society into a modern functional world-culture and the incorporation of that part of the world in the world-system. The anti-western feelings after the independence resulted in a political Pan-Africanism. However, sport and more specific soccer, a typical product of the western domination, has not been rejected. On the contrary, local politicians used it to create a national identity. The strong link between soccer and soil resulted in a strong form of topophily. This connection was transformed into sportnationalism and created in the, through artificial borders developed, nations a unity and a national pride. The outcome of sport games was used to demonstrate the successes in politics and economics. The absence of any political platform on which the Third World had a strong voice brought about that the international sport scene, such as the FIFA, was used for the unification of the Third World against the former colonial powers. Nowadays, the globalisation processes result in an increasing labour migration of African football players to the rich core competitions in Europe. This form of migration can be classified as another form of "cash crop" or in this case "foot drain.. ""As Roman imperialism laid the foundation of modern civilisation and led wild barbarians of these

  4. Surveillance of the bioterrorist threat: a primary care response.

    Science.gov (United States)

    Fleming, D M; Barley, M A; Chapman, R S

    2004-03-01

    Threats from bioterrorism are of national and international concern. We outline a system of disease surveillance covering a selection of diseases linked to potential bioterrorist threats, based on the weekly returns service of the Royal College of General Practitioners and covering a surveillance population of 650,000 in England and Wales. Practices record working diagnoses and the episode type (distinguishing new episodes of illness from ongoing consultations) on patients' computerised medical records. These are interrogated twice weekly by using automated routines. The registered population and persons consulting for each Read code (group of codes) are counted in sex and age specific groups and the data forwarded electronically to the Research Unit, where the results are consolidated by region (North, Central, South). Weekly incidence rates between October 2001 and September 2002 were compared with the weekly average over the past seven years for 13 selected conditions. Detailed data are presented for three conditions (asthma, infections of the skin, disorders of the peripheral nervous system). For asthma increased incidence was reported in weeks 31 and 32 of 2002, predominantly in the Central region. For the other two conditions no unusual peaks of incidence were observed in any region. Operational research based on disciplined recording of morbidity in general practice can deliver timely surveillance data on bioterrorist threats.

  5. Stereotype threat and executive functions: which functions mediate different threat-related outcomes?

    Science.gov (United States)

    Rydell, Robert J; Van Loo, Katie J; Boucher, Kathryn L

    2014-03-01

    Stereotype threat research shows that women's math performance can be reduced by activating gender-based math stereotypes. Models of stereotype threat assert that threat reduces cognitive functioning, thereby accounting for its negative effects. This work provides a more detailed understanding of the cognitive processes through which stereotype threat leads women to underperform at math and to take risks, by examining which basic executive functions (inhibition, shifting, and updating) account for these outcomes. In Experiments 1 and 2, women under threat showed reduced inhibition, reduced updating, and reduced math performance compared with women in a control condition (or men); however, only updating accounted for women's poor math performance under threat. In Experiment 3, only updating accounted for stereotype threat's effect on women's math performance, whereas only inhibition accounted for the effect of threat on risk-taking, suggesting that distinct executive functions can account for different stereotype threat-related outcomes.

  6. Enhanced Memory for both Threat and Neutral Information Under Conditions of Intergroup Threat

    Directory of Open Access Journals (Sweden)

    Yong eZhu

    2015-11-01

    Full Text Available Few studies have examined the effect of intergroup threat on cognitive outcomes such as memory. Different theoretical perspectives can inform how intergroup threat should affect memory for threat-relevant and neutral information, such as the mood-congruency approach, Yerkes-Dodson law, Easterbrook’s theory, and also evolutionary perspectives. To test among these, we conducted two experiments to examine how exposure to intergroup threats affected memory compared to control conditions. In study 1, we manipulated symbolic threat and examined participants’ memory for threat and neutral words. In study 2, memory performance was assessed following the induction of realistic threat. Across the studies, in the control condition participants showed better memory for threat-related than neutral information. However, participants under threat remembered neutral information as well as threat-related information. In addition, participants in the threat condition remembered threat-related information as well as participants in the control condition. The findings are discussed in terms of automatic vigilance processes but also the effects of threat on arousal and its effect on information processing. This latter perspective, suggests paradoxically, that under some circumstances involving an outgroup threat, non-threatening information about outgroups can be extensively processed.

  7. Countering the Nuclear Terrorist Threat

    Energy Technology Data Exchange (ETDEWEB)

    Vantine, H C

    2002-10-04

    The nuclear/radioactive threat to homeland security posed by terrorists can be broken into four categories. Of highest concern is the use of an improvised nuclear device (IND). An IND, as its name implies, is a nuclear explosive device. It produces nuclear yield, and this nuclear yield has catastrophic effects. An IND is the ultimate terrorist weapon, and terrorist groups are actively attempting to acquire nuclear weapons. Detonation of an IND could dwarf the devastation of the September 11 attack on the World Trade Center. Dealing with the aftermath of an IND would be horrific. Rescue efforts and cleanup would be hazardous and difficult. Workers would have to wear full protection suits and self-contained breathing apparatus. Because of the residual radioactivity, in certain locations they could only work short times before acquiring their ''lifetime'' dose. As with the Chernobyl event, some rescue workers might well expose themselves to lethal doses of radiation, adding to the casualty toll. Enormous volumes of contaminated debris would have to be removed and disposed. If a terrorist group decides not to pursue an actual nuclear device, it might well turn to Radiological Dispersal Devices (RDDs) or ''dirty bombs'' as they are often called. RDDs spread radioactivity but they do not generate nuclear yield. The fabrication of an RDD requires radioactive material and a dispersal mechanism. Radioactive materials are used all over the world for medical, industrial, and research applications. Standards for safe handling and accountability of radioactive material vary around the world. Stories in the press suggest inadequate controls on radiological materials in parts of the world. The effects of an RDD vary widely, and are measured in terms of contamination area, health effects to the exposed population, and economic consequences. Even a negligible, but measurable, exposure would exploit the general public's fear of things

  8. Chikungunya - a serious threat for public health

    Directory of Open Access Journals (Sweden)

    Hrnjaković-Cvjetković Ivana B.

    2015-01-01

    Full Text Available Introduction. Chikungunya is a contagious disease caused by Chikungunya virus, an arbovirus from the Togaviridae family. This infection is mostly spread by mosquitoes from the genus Aedes, especially Aedes albopictus, which have spread from Asia to America and Europe including some countries surrounding Serbia. Epidemiologic Features. The outbreak of epidemics has been reported in Philippines, Sumatra, Java, Indonesia, West Africa region (from Senegal to Cameroon, Congo, Nigeria, Angola, Uganda, Guinea, Malawi, Central African Republic, Burundi, South Africa and India. At the beginning of the 21st century, large outbreaks were recorded on the island of Réunion. During 2006, 1.400.000 cases of chikungunya infection were recorded in India. Local transmission of infection in continental Europe was reported from Northeast Italy (254 suspected and 78 laboratory confirmed cases in Emilia-Romagna region and France (two cases in 2010. From December 2013 to June 2014, 5.294 confirmed cases and more than 180.000 suspected cases of chikungunya were reported in the Caribbean. Clinical Findings. The disease presents suddenly with fever, rush and arthralgia. In general, chikungunya is a mild self - limited disease. Less often, it may be presented with signs of meningoencephalitis or fulminant hepatitis, sometimes with fatal outcome. Conclusion. Fast developing international traffic and booming tourism as well as the vector spreading from its homeland make chikungunya a real threat to our country. [Projekat Ministarstva nauke Republike Srbije, br. TR31084 i br. TR43007

  9. A reward for patience and suffering – Ethnomycology and commodification of desert truffles among Sahrawi refugees and nomads of Western Sahara

    NARCIS (Netherlands)

    Volpato, G.; Rossi, D.; Dentoni, D.

    2013-01-01

    A Reward for Patience and Suffering: Ethnomycology and Commodification of Desert Truffles among Sahrawi Refugees and Nomads of Western Sahara. This paper reflects on the role of ethnobiological knowledge and practices for refugees’ agency by focusing on the use and commodification of desert truffles

  10. ARCHAEOLOGICAL AND ENVIRONMENTAL CHANGES BETWEEN 9500 BP AND 4500 BP: A CONTRIBUTION FROM THE SAHARA TO UNDERSTAND EXPANDING DROUGHTS IN THE “GREAT MEDITERRANEAN”

    Directory of Open Access Journals (Sweden)

    E. A.A. Garcea

    2013-03-01

    Full Text Available The Sahara is more connected to the Mediterranean than often assumed and palynology, in particular, has provided evidence of past interrelations between the Mediterranean and the Sahara with pollen spectra from prehistoric Saharan deposits including Mediterranean taxa. In order to show human-environment relationships and populations’ strategies in response to changing environments, this paper presents a case study from the southern Sahara. This region offered a natural laboratory for the study of human/climate interaction as the range of environmental change extended from flood to drought, forcing people to cope with periodic environmental instability. When the tropical rainfall belt migrated northward, watertable outcropped in interdunal depressions and formed permanent lakes, which alternated with severe arid spells. As a case study, this paper presents the results of interdisciplinary investigations on climate changes, human adaptations and subsistence strategies at Gobero, in the southern Sahara of Niger. Gobero is a restricted archaeological area comprising 8 sites that surround the shores of a palaeolake. It was intermittently occupied between about 9500 cal years BP and 4500 BP. Due to alternating environmental conditions it could only be occupied at the beginning and at the end of the most humid periods.

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

    Science.gov (United States)

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

    2016-01-01

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

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

    Science.gov (United States)

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

    2008-10-28

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

  13. Africa South of the Sahara, Rationale and Introduction: An Experimental Program of Study for Secondary School Social Studies Students. Teaching Guide.

    Science.gov (United States)

    Carnegie-Mellon Univ., Pittsburgh, PA. Project Africa.

    The articulation of a rationale for Project Africa's instructional program, the collection of materials for improving inquiry-oriented instruction at the secondary level about Africa south of the Sahara, and the preparation of teaching and study guides have been completed. This geographic region, rather than the whole continent, was chosen to…

  14. Peoples of Africa, Topic 1. Africa South of the Sahara: A Program of Study for Secondary School Social Studies Students. (Teaching and Student Guides).

    Science.gov (United States)

    Carnegie-Mellon Univ., Pittsburgh, PA. Project Africa.

    This teaching guide and student text for Project Africa's curriculum program, "Africa South of the Sahara," deal with how four typical contemporary African peoples acquired their present way of life: (1) the Hausa of Northern Nigeria, (2) the Kung Bushmen of the Kalahari Desert, (3) the Mech'a Galla of Ethiopa, and (4) the Kikuyu of…

  15. Countering 21st Century Threats

    DEFF Research Database (Denmark)

    Scharling Pedersen, Peter; Pillai, Chad M.; Hun, Lee Jae

    2015-01-01

    The United States and its Allies confront an increasingly volatile world where threats range from traditional state-on-state challenges to non-state transnational networks. To successfully combat these 21st Century problems, in an era of resource and geo-political power constraints, the U......), Counter-Terrorism (CT), and Security and Stability Operations (SSO). • Establishing a construct that allows a strategic Whole-of-Government capacity for operations coordinated by joint interagency task forces. • Continue to developing the Global SOF network. • Increased intelligence sharing in areas...... (UW). Other obstacles such as resolving tensions in U.S. statutory law between traditional military and intelligence activities, bridging the gap with non-security Departments and Agencies, and developing the necessary trust with bilateral and multilateral partners are components that need...

  16. World's soils are under threat

    Science.gov (United States)

    Montanarella, Luca; Pennock, Daniel Jon; McKenzie, Neil; Badraoui, Mohamed; Chude, Victor; Baptista, Isaurinda; Mamo, Tekalign; Yemefack, Martin; Singh Aulakh, Mikha; Yagi, Kazuyuki; Hong, Suk Young; Vijarnsorn, Pisoot; Zhang, Gan-Lin; Arrouays, Dominique; Black, Helaina; Krasilnikov, Pavel; Sobocká, Jaroslava; Alegre, Julio; Henriquez, Carlos Roberto; de Lourdes Mendonça-Santos, Maria; Taboada, Miguel; Espinosa-Victoria, David; AlShankiti, Abdullah; Kazem AlaviPanah, Sayed; El Mustafa Elsheikh, Elsiddig Ahmed; Hempel, Jon; Camps Arbestain, Marta; Nachtergaele, Freddy; Vargas, Ronald

    2016-02-01

    The Intergovernmental Technical Panel on Soils has completed the first State of the World's Soil Resources Report. Globally soil erosion was identified as the gravest threat, leading to deteriorating water quality in developed regions and to lowering of crop yields in many developing regions. We need to increase nitrogen and phosphorus fertilizer use in infertile tropical and semi-tropical soils - the regions where the most food insecurity among us are found - while reducing global use of these products overall. Stores of soil organic carbon are critical in the global carbon balance, and national governments must set specific targets to stabilize or ideally increase soil organic carbon stores. Finally the quality of soil information available for policy formulation must be improved - the regional assessments in the State of the World's Soil Resources Report frequently base their evaluations on studies from the 1990s based on observations made in the 1980s or earlier.

  17. Dissolution Threats and Legislative Bargaining

    DEFF Research Database (Denmark)

    Becher, Michael; Christiansen, Flemming Juul

    2015-01-01

    Chief executives in many parliamentary democracies have the power to dissolve the legislature. Despite a well-developed literature on the endogenous timing of parliamentary elections, political scientists know remarkably little about the strategic use of dissolution power to influence policymaking....... To address this gap, we propose and empirically evaluate a theoretical model of legislative bargaining in the shadow of executive dissolution power. The model implies that the chief executive's public support and legislative strength, as well as the time until the next constitutionally mandated election......, are important determinants of the use and effectiveness of dissolution threats in policymaking. Analyzing an original time-series data set from a multiparty parliamentary democracy, we find evidence in line with key empirical implications of the model....

  18. Insider Threat Mitigation Workshop Instructional Materials

    Energy Technology Data Exchange (ETDEWEB)

    Gibbs, Philip [Brookhaven National Lab. (BNL), Upton, NY (United States); Larsen, Robert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); O' Brien, Mike [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Rodriquez, Jose [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2008-01-01

    Insiders represent a formidable threat to nuclear facilities. This set of workshop materials covers methodologies to analyze and approaches to mitigate the threat of an insider attempting abrupt theft of nuclear materials. This report is a compilation of workshop materials consisting of lectures on technical and administrative measures used in Physical Protection (PP) and Material Control and Accounting (MC&A) and methods for analyzing their effectiveness against a postulated insider threat.

  19. Bias Adjusted Precipitation Threat Scores

    Directory of Open Access Journals (Sweden)

    F. Mesinger

    2008-04-01

    Full Text Available Among the wide variety of performance measures available for the assessment of skill of deterministic precipitation forecasts, the equitable threat score (ETS might well be the one used most frequently. It is typically used in conjunction with the bias score. However, apart from its mathematical definition the meaning of the ETS is not clear. It has been pointed out (Mason, 1989; Hamill, 1999 that forecasts with a larger bias tend to have a higher ETS. Even so, the present author has not seen this having been accounted for in any of numerous papers that in recent years have used the ETS along with bias "as a measure of forecast accuracy".

    A method to adjust the threat score (TS or the ETS so as to arrive at their values that correspond to unit bias in order to show the model's or forecaster's accuracy in extit{placing} precipitation has been proposed earlier by the present author (Mesinger and Brill, the so-called dH/dF method. A serious deficiency however has since been noted with the dH/dF method in that the hypothetical function that it arrives at to interpolate or extrapolate the observed value of hits to unit bias can have values of hits greater than forecast when the forecast area tends to zero. Another method is proposed here based on the assumption that the increase in hits per unit increase in false alarms is proportional to the yet unhit area. This new method removes the deficiency of the dH/dF method. Examples of its performance for 12 months of forecasts by three NCEP operational models are given.

  20. Information security practices emerging threats and perspectives

    CERN Document Server

    Awad, Ahmed; Woungang, Isaac

    2017-01-01

    This book introduces novel research targeting technical aspects of protecting information security and establishing trust in the digital space. New paradigms, and emerging threats and solutions are presented in topics such as application security and threat management; modern authentication paradigms; digital fraud detection; social engineering and insider threats; cyber threat intelligence; intrusion detection; behavioral biometrics recognition; hardware security analysis. The book presents both the important core and the specialized issues in the areas of protection, assurance, and trust in information security practice. It is intended to be a valuable resource and reference for researchers, instructors, students, scientists, engineers, managers, and industry practitioners. .

  1. Phylogeny of North African Agama lizards (Reptilia: Agamidae) and the role of the Sahara desert in vertebrate speciation.

    Science.gov (United States)

    Gonçalves, Duarte V; Brito, José C; Crochet, Pierre-André; Geniez, Philippe; Padial, José M; Harris, D James

    2012-09-01

    The origin of Saharan biodiversity is poorly understood, in part because the geological and paleoclimatic events that presumably shaped species diversity are still controversial, but also because few studies have explored causal explanations for the origin of Saharan diversity using a phylogenetic framework. Here, we use mtDNA (16S and ND4 genes) and nDNA (MC1R and CMOS genes) to infer the relationships and biogeographic history of North African agamas (genus Agama). Agamas are conspicuous, diverse and abundant African lizards that also occur in the Saharan xeric and mesic environments. Our results revealed the presence of three Agama lineages in North Africa: one Afrotropical, one Sahelo-Saharan, and one broadly distributed in North Africa and mainly Saharan. Southern Mauritania contains the highest known diversity, with all three lineages present. Results suggest that agamas colonized the Sahara twice, but only one lineage was able to radiate and diversify there. Species in the Saharan lineage are mostly allopatric, and their splitting, genetic diversity and distribution are greatly explained by mountain ranges. One species in this lineage has colonized the Mediterranean climatic zone (A. impalearis), and another one the Sahel savannah (A. boueti). The other lineage to colonize the Sahara corresponds to A. boulengeri, an eminently Sahelian species that also inhabits Saharan mountain ranges in Mauritania and Mali. Phylogenetic analyses indicate that allopatric montane populations within some currently recognized species are also genetically divergent. Our study therefore concludes that vicariant speciation is a leading motor of species diversification in the area: Inside the Sahara, associated to mountain-ranges isolated by dune seas and bare plains; outside, associated to less harsh climates to the North and South. Paleoclimatic oscillations are suggested as causal explanations of the vicariant distribution and origin of species. Agamas are thought to have

  2. The evolution of the 87Sr/86Sr in the Dead Sea brine: from the Sedom lagoon to Sahara dusts

    Science.gov (United States)

    Stein, Mordechai

    2016-04-01

    The history of water-bodies in the Dead Sea brines commenced with the intrusion of the Sedom lagoon, possibly in the late Neogene and continued with the development of hypersaline and freshwater lakes (e.g. the modern Dead Sea and Sea of Galilee). 87Sr/86Sr ratios in these water-bodies decreased over the past ~ 5-6 Ma from 0.7087-0.7084 in salts deposited in the Sedom lagoon to ~ 0.7080 in modern Dead Sea brine. The 87Sr/86Sr ratios in the salts deposited from Sedom lagoon are significantly lower than those of the contemporaneous late Miocene seawater (~0.709). This difference was attributed to modification of the 87Sr/86Sr ratio in the Sedom lagoon solution by influx of Ca-chloride brines. The brines, in turn were formed by dolomitization of marine limestones of the DSR Cretaceous wall rocks (87Sr/86Sr ~ 0.7075) by the ingressing evaporated seawaters (Stein et al., 2000). After the disconnection of the Sedom lagoon from the open sea freshwater filled the lakes that occupied the Dead Sea basin. The freshwater influx modified the strontium isotope and chemical composition of the brine and provided bicarbonate and sulfate to the lake that led the precipitation of primary aragonite and gypsum. Freshwater that currently enter the lake are characterize by 87Sr/86Sr ~ 0.7081, significantly higher than the Cretaceous carbonates. Settled dust that deposits on the Judea Mountains is composed of calcite and quartz grains and is characterized by 87Sr/86Sr ratios ~ 0.7084. It appears that significant amounts of the strontium that entered the lakes with the freshwater originated from dissolution of the dust calcites. Large amounts of dust were transported from the Sahara desert to the Dead Sea watershed during glacial periods when the Sahara was dry and sea-level was low. The source of the detrital calcites however, is not known. They could be derived from dry paleo-lakes in the Sahara that were previously filled by waters that retained the required strontium isotope

  3. Threat by association: do distant intergroup threats carry-over into local intolerance?

    Science.gov (United States)

    Bouman, Thijs; van Zomeren, Martijn; Otten, Sabine

    2014-09-01

    Individuals are often confronted with intergroup threats, yet many of these threats emanate from distant groups that most individuals are unlikely to encounter in their local environment. An important yet unanswered question is whether reactions to those threats, such as intolerance towards the threatening group, carry over to other groups that individuals actually do encounter in their local environment (e.g., immigrants). The main goal of our studies was to experimentally identify this carry-over effect of intergroup threat. Specifically, we hypothesized that (by definition relatively abstract) symbolic threats (e.g., threats to the ingroup's worldview) have an especially strong carry-over potential because those threats can be easily attributed to other outgroups. We tested these predictions in one correlational and two experimental studies. The results of all three studies confirmed our hypothesis that particularly distant symbolic threats were predictive of intolerance towards local outgroups.

  4. Vibrotactile and visual threat cueing with high g threat intercept in dynamic flight simulation

    NARCIS (Netherlands)

    Eriksson, L.; Erp, J.B.F. van; Carlander, O.; Levin, B.; Veen, H.A.H.C. van; Veltman, J.E.

    2006-01-01

    In a TNO and FOI joint study, nine fighter pilots participated in a threat detection and intercept experiment in the Swedish Dynamic Flight Simulator. Visual threat cueing with a simulated Gripen aircraft head-up display (HUD) symbology was compared with combined visual and vibrotactile threat cuein

  5. Threat by association : Do distant intergroup threats carry-over into local intolerance?

    NARCIS (Netherlands)

    Bouman, Thijs; van Zomeren, Martijn; Otten, Sabine

    2014-01-01

    Individuals are often confronted with intergroup threats, yet many of these threats emanate from distant groups that most individuals are unlikely to encounter in their local environment. An important yet unanswered question is whether reactions to those threats, such as intolerance towards the thre

  6. Implications of high altitude desert dust transport from Western Sahara to Nile Delta during biomass burning season.

    Science.gov (United States)

    Prasad, Anup K; El-Askary, Hesham; Kafatos, Menas

    2010-11-01

    The air over major cities and rural regions of the Nile Delta is highly polluted during autumn which is the biomass burning season, locally known as black cloud. Previous studies have attributed the increased pollution levels during the black cloud season to the biomass or open burning of agricultural waste, vehicular, industrial emissions, and secondary aerosols. However, new multi-sensor observations (column and vertical profiles) from satellites, dust transport models and associated meteorology present a different picture of the autumn pollution. Here we show, for the first time, the evidence of long range transport of dust at high altitude (2.5-6 km) from Western Sahara and its deposition over the Nile Delta region unlike current Models. The desert dust is found to be a major contributor to the local air quality which was previously considered to be due to pollution from biomass burning enhanced by the dominant northerly winds coming from Europe.

  7. Bensaâd Ali (dir., L’eau et ses enjeux au Sahara, Iremam, Karthala, 2011, 242 p.

    Directory of Open Access Journals (Sweden)

    Jean-Louis Marçot

    2011-11-01

    Full Text Available Je dirai en premier ma déception. Comme le suggère Ali Bensaâd à l’entrée du livre qu’il a dirigé, l’enjeu de l’eau au Sahara n’est ni plus ni moins que la conservation de la vie dans ce milieu qui lui est particulièrement hostile - la vie sous tous ses aspects. Or cet enjeu « vital » a été négligé au profit d’une approche micro-géographique. C’est pourtant par cette entrée que le travail collectif aurait pu légitimement intéresser un vaste public. Comment l’eau existe-t-elle à l’état naturel...

  8. Dust and biological aerosols from the Sahara and Asia influence precipitation in the western U.S.

    Science.gov (United States)

    Creamean, Jessie M; Suski, Kaitlyn J; Rosenfeld, Daniel; Cazorla, Alberto; DeMott, Paul J; Sullivan, Ryan C; White, Allen B; Ralph, F Martin; Minnis, Patrick; Comstock, Jennifer M; Tomlinson, Jason M; Prather, Kimberly A

    2013-03-29

    Winter storms in California's Sierra Nevada increase seasonal snowpack and provide critical water resources and hydropower for the state. Thus, the mechanisms influencing precipitation in this region have been the subject of research for decades. Previous studies suggest Asian dust enhances cloud ice and precipitation, whereas few studies consider biological aerosols as an important global source of ice nuclei (IN). Here, we show that dust and biological aerosols transported from as far as the Sahara were present in glaciated high-altitude clouds coincident with elevated IN concentrations and ice-induced precipitation. This study presents the first direct cloud and precipitation measurements showing that Saharan and Asian dust and biological aerosols probably serve as IN and play an important role in orographic precipitation processes over the western United States.

  9. Cosmic Impacts: The DoomsDay Threat

    Science.gov (United States)

    McGaha, J.

    1998-07-01

    Recent science fiction movies (Deep Impact and Armageddon) have brought public attention to the threat of possible impacts from space. Just how real is this threat and what would be the consequences of such an impact? Can we do anything to prevent it? The survival of civilization may depend on it.

  10. Target threat assessment using fuzzy sets theory

    Directory of Open Access Journals (Sweden)

    Ehsan Azimirad

    2015-08-01

    Full Text Available The threat evaluation is significant component in target classification process and is significant in military and non military applications. Small errors or mistakes in threat evaluation and target classification especial in military applications can result in huge damage of life and property. Threat evaluation helps in case of weapon assignment, and intelligence sensor support system. It is very important factor to analyze the behavior of enemy tactics as well as our surveillance. This paper represented a precise description of the threat evaluation process using fuzzy sets theory. A review has been carried out regarding which parameters that have been suggested for threat value calculation. For the first time in this paper, eleven parameters are introduced for threat evaluation so that this parameters increase the accuracy in designed system. The implemented threat evaluation system has been applied to a synthetic air defense scenario and four real time dynamic air defense scenarios. The simulation results show the correctness, accuracy, reliability and minimum errors in designing of threat evaluation system

  11. Game Theoretic Risk Analysis of Security Threats

    CERN Document Server

    Bier, Vicki M

    2008-01-01

    Introduces reliability and risk analysis in the face of threats by intelligent agents. This book covers applications to networks, including problems in both telecommunications and transportation. It provides a set of tools for applying game theory TO reliability problems in the presence of intentional, intelligent threats

  12. How you perceive threat determines your behavior

    Directory of Open Access Journals (Sweden)

    Orlando Fernandes Junior

    2013-10-01

    Full Text Available The prioritization of processing emotional stimuli usually produces deleterious effects on task performance when it distracts from a task. One common explanation is that brain resources are consumed by emotional stimuli, diverting resources away from executing the task. Viewing unpleasant stimuli also generates defensive reactions, and these responses may be at least partially responsible for the effect of the emotional modulation observed in various reaction time (RT paradigms. We investigated whether modulatory effects on RT vary if we presented threat stimuli to prompt different defensive responses. To trigger different responses, we manipulated threat perception by moving the direction of threatening stimuli. Threatening or neutral stimuli were presented as distractors during a bar orientation discrimination task. The results demonstrated that threat stimuli directed towards the observer produced a decrease in RT; in contrast, threat stimuli directed away from the observer produced an increase in RT, when compared to neutral stimuli. Accelerated RT during direct threat stimuli was attributed to increased motor preparation resulting from strong activation of the defense response cascade. In contrast, no direct threat stimuli likely activated the defense cascade, but less intensively, prompting immobility. Different threat stimuli produced varying effects, which was interpreted as evidence that the modulation of RT by emotional stimuli represents the summation of attentional and motivational effects. Additionally, participants who had been previously exposed to diverse types of violent crime were more strongly influenced by direct threat stimuli. In sum, our data support the concept that emotions are indeed action tendencies.

  13. Perception of the Threat of Terrorism.

    Science.gov (United States)

    Cohen-Louck, Keren

    2016-04-28

    In light of the tense and ongoing security situation in Israel, one important issue that needs to be analyzed and understood is the perception of terrorism threats. Most studies focused mainly on the psychological implications of terrorist acts; this study examines the complexity of the manner in which the individual perceives the threat of terrorism. In all, 40 Israeli adults (22 women and 18 men) were interviewed using semistructured in-depth interviews. Qualitative analysis indicates that the components of the perception of terrorism that construct the evaluation and subjective perception of the participants are as follows: (a) perception of control, which is a feeling of loss of control and helplessness due to uncertainty, inability to predict threats, and the vagueness of the threat; (b) perception of vulnerability to the threat, such as a feeling of vulnerability to and potential victimization by terrorism; and (c) perception of fear of terrorism that includes responses of fear, anxiety, feeling of danger, and emotional distress. In addition, gender differences were found in the analysis. The findings of this study help gain a better understanding as to how people perceive the threat of terrorism. The findings also enable an understanding of the complexity of living under ongoing terrorism threats and may assist in understanding how citizens cope with and adjust to this threat.

  14. The Nature of the Bioterrorism Threat

    Energy Technology Data Exchange (ETDEWEB)

    Regens, J. L.

    2003-02-25

    This analysis provides an overview of the nature of the bioterrorism threat. It identifies potential CDC Class A biological agents that are likely candidates for use in a terrorist incident and describes the known sources of vulnerability. The paper also summarizes S&T resources/needs and assesses response options for achieving effective biodefense against terrorist threats.

  15. Spatial Pattern Determination of Biodiversity Threats at Landscape Level (Case Study: Golestan Province

    Directory of Open Access Journals (Sweden)

    R. Mirzaei

    2015-06-01

    Full Text Available Mapping spatial patterns of potential biodiversity threats is one of the important steps for effective conservation planning and activities. To determine the spatial patterns of threats in Golestan province, 12 criteria in four main groups including structural (fractal coefficient of perimeter, circularity ratio of area, average slope, compositional aspects of biodiversity (presence of species at risk, non-biological threats (distance to city, distance to village, distance to road, distance to infrastructure, distance to agricultural land, soil pollution, risk of fire and isolation (Nearest Neighbor Index were used. These data layers were digitized in GIS environment and were weighted through Analytical Hierarchy Process. A weighted linear combination was then used to map the spatial pattern of biodiversity threats in the province. Compositional aspect (0.59, non-biological threats (0.23, isolation (0.11, and structural aspect (0.07 were relatively weighted in the order of importance. Central parts of the province and patches in the northern and southern parts were recognized to be more exposed to biodiversity threats. The central parts of the province were mostly threatened by urban, industrial, road and agricultural development, whereas the northern and southern parts were recognized as areas of conservation importance having a variety of threatened birds.

  16. Source apportionment and seasonal variation of PM2.5 in a Sub-Sahara African city: Nairobi, Kenya

    Directory of Open Access Journals (Sweden)

    S. M. Gaita

    2014-04-01

    Full Text Available Sources of airborne particulate matter and their seasonal variation in urban areas in Sub-Sahara Africa are poorly understood due to lack of long-term measurement data. In view of this, airborne fine particles matter (particle diameter ≤ 2.5 μm, PM2.5 were collected between May 2008 and April 2010 at two sites (urban background site and suburban site within the Nairobi metropolitan area. A total of 780 samples were collected and analyzed for particulate mass, black carbon (BC and thirteen trace elements. The average PM2.5 concentration at the urban background site was 20 ± 8 μg m−3 whereas the concentration at the suburban site was 13 ± 8 μg m−3. The daily PM2.5 concentrations exceeded 25 μg m−3 (the World Health Organization 24 h guideline value 29% of the days at the urban background site and 7% of the days at the suburban site. At both sites, BC, Fe, S and Cl accounted for approximately 80% of all detected elements. Positive Matrix Factorization analysis identified five source factors that contribute to PM2.5 in Nairobi; traffic, mineral dust, secondary aerosol, industrial and combustion. Mineral dust and traffic factors were related to approximately 74% of PM2.5. Identified source factors exhibited seasonal variation though traffic factor was prominently consistent throughout the sampling period. The results provide information that can be exploited for policy formulation and mitigation strategies to control air pollution in Sub-Sahara African cities.

  17. Discrimination and validation of clouds and dust aerosol layers over the Sahara desert with combined CALIOP and IIR measurements

    Science.gov (United States)

    Liu, Jingjing; Chen, Bin; Huang, Jianping

    2014-02-01

    This study validates a method for discriminating between daytime clouds and dust aerosol layers over the Sahara Desert that uses a combination of active CALIOP (Cloud-Aerosol Lidar with Orthogonal Polarization) and passive IIR (Infrared Imaging Radiometer) measurements; hereafter, the CLIM method. The CLIM method reduces misclassification of dense dust aerosol layers in the Sahara region relative to other techniques. When evaluated against a suite of simultaneous measurements from CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations), CloudSat, and the MODIS (Moderate-resolution Imaging Spectroradiometer), the misclassification rate for dust using the CLIM technique is 1.16% during boreal spring 2007. This rate is lower than the misclassification rates for dust using the cloud aerosol discriminations performed for version 2 (V2-CAD; 16.39%) or version 3 (V3-CAD; 2.01%) of the CALIPSO data processing algorithm. The total identification errors for data from in spring 2007 are 13.46% for V2-CAD, 3.39% for V3-CAD, and 1.99% for CLIM. These results indicate that CLIM and V3-CAD are both significantly better than V2-CAD for discriminating between clouds and dust aerosol layers. Misclassifications by CLIM in this region are mainly limited to mixed cloud-dust aerosol layers. V3-CAD sometimes misidentifies low-level aerosol layers adjacent to the surface as thin clouds, and sometimes fails to detect thin clouds entirely. The CLIM method is both simple and fast, and may be useful as a reference for testing or validating other discrimination techniques and methods.

  18. Discrimination and Validation of Clouds and Dust Aerosol Layers over the Sahara Desert with Combined CALIOP and IIR Measurements

    Institute of Scientific and Technical Information of China (English)

    LIU Jingjing; CHEN Bin; HUANG Jianping

    2014-01-01

    This study validates a method for discriminating between daytime clouds and dust aerosol layers over the Sahara Desert that uses a combination of active CALIOP (Cloud-Aerosol Lidar with Orthogonal Polar-ization) and passive IIR (Infrared Imaging Radiometer) measurements; hereafter, the CLIM method. The CLIM method reduces misclassification of dense dust aerosol layers in the Sahara region relative to other techniques. When evaluated against a suite of simultaneous measurements from CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations), CloudSat, and the MODIS (Moderate-resolution Imag-ing Spectroradiometer), the misclassification rate for dust using the CLIM technique is 1.16%during boreal spring 2007. This rate is lower than the misclassification rates for dust using the cloud aerosol discriminations performed for version 2 (V2-CAD;16.39%) or version 3 (V3-CAD;2.01%) of the CALIPSO data processing algorithm. The total identification errors for data from in spring 2007 are 13.46% for V2-CAD, 3.39% for V3-CAD, and 1.99%for CLIM. These results indicate that CLIM and V3-CAD are both significantly better than V2-CAD for discriminating between clouds and dust aerosol layers. Misclassifications by CLIM in this region are mainly limited to mixed cloud-dust aerosol layers. V3-CAD sometimes misidentifies low-level aerosol layers adjacent to the surface as thin clouds, and sometimes fails to detect thin clouds entirely. The CLIM method is both simple and fast, and may be useful as a reference for testing or validating other discrimination techniques and methods.

  19. Quantifying the "Energy-Return-on-Investment" of desert greening in the Sahara/Sahel using a Global Climate Model

    Science.gov (United States)

    Bowring, S. P. K.; Miller, L. M.; Ganzeveld, L.; Kleidon, A.

    2013-08-01

    "Greening" the world's deserts has been proposed as a way to produce additional food, sequester carbon, and alter the climate of desert regions. Here, we quantify the potential benefits in terms of energetic quantities and compare these to the energetic costs. We then compare these using the metric of Energy-Return-On-Investment (EROI). We apply EROI to a series of global climate model simulations where the arid Sahara/Sahel region is irrigated with various rates of desalinated water to produce biomass. The energy content of this biomass is greater than the energy input rate for a minimum irrigation rate of about 200 mm yr-1 in the winter and 500 mm yr-1 in the summer, thereby yielding an EROI ratio > 1 : 1, expressing energetic sustainability. Quantified annually, the EROI was > 1 : 1 for irrigation rates more than 500 mm yr-1, progressively increasing to a maximum of 1.8 : 1 with 900 mm yr-1, and then decreasing with further increases in the irrigation rate. Including the precipitation feedback arising from changes in moisture-recycling within the study region approximately doubles these EROI ratios. This overall result varies spatially and temporally, so while the entire Sahara/Sahel region is irrigated equally, the western coastal region from June to August had the highest EROI. Other factors would complicate such a large-scale modification of the Earth System, but this sensitivity study concludes that with a required energy input, desert greening may be energetically sustainable. Furthermore, we suggest that this type of EROI-analysis could be applied as a metric to assess a diverse range of human alterations to, and interventions within, the Earth System.

  20. Security threats categories in healthcare information systems.

    Science.gov (United States)

    Samy, Ganthan Narayana; Ahmad, Rabiah; Ismail, Zuraini

    2010-09-01

    This article attempts to investigate the various types of threats that exist in healthcare information systems (HIS). A study has been carried out in one of the government-supported hospitals in Malaysia.The hospital has been equipped with a Total Hospital Information System (THIS). The data collected were from three different departments, namely the Information Technology Department (ITD), the Medical Record Department (MRD), and the X-Ray Department, using in-depth structured interviews. The study identified 22 types of threats according to major threat categories based on ISO/IEC 27002 (ISO 27799:2008). The results show that the most critical threat for the THIS is power failure followed by acts of human error or failure and other technological factors. This research holds significant value in terms of providing a complete taxonomy of threat categories in HIS and also an important component in the risk analysis stage.

  1. Stereotype threat prevents perceptual learning.

    Science.gov (United States)

    Rydell, Robert J; Shiffrin, Richard M; Boucher, Kathryn L; Van Loo, Katie; Rydell, Michael T

    2010-08-10

    Stereotype threat (ST) refers to a situation in which a member of a group fears that her or his performance will validate an existing negative performance stereotype, causing a decrease in performance. For example, reminding women of the stereotype "women are bad at math" causes them to perform more poorly on math questions from the SAT and GRE. Performance deficits can be of several types and be produced by several mechanisms. We show that ST prevents perceptual learning, defined in our task as an increasing rate of search for a target Chinese character in a display of such characters. Displays contained two or four characters and half of these contained a target. Search rate increased across a session of training for a control group of women, but not women under ST. Speeding of search is typically explained in terms of learned "popout" (automatic attraction of attention to a target). Did women under ST learn popout but fail to express it? Following training, the women were shown two colored squares and asked to choose the one with the greater color saturation. Superimposed on the squares were task-irrelevant Chinese characters. For women not trained under ST, the presence of a trained target on one square slowed responding, indicating that training had caused the learning of an attention response to targets. Women trained under ST showed no slowing, indicating that they had not learned such an attention response.

  2. In Brief: Forecasting meningitis threats

    Science.gov (United States)

    Showstack, Randy

    2008-12-01

    The University Corporation for Atmospheric Research (UCAR), in conjunction with a team of health and weather organizations, has launched a project to provide weather forecasts to medical officials in Africa to help reduce outbreaks of meningitis. The forecasts will enable local health care providers to target vaccination programs more effectively. In 2009, meteorologists with the National Center for Atmospheric Research, which is managed by UCAR, will begin issuing 14-day forecasts of atmospheric conditions in Ghana. Later, UCAR plans to work closely with health experts from several African countries to design and test a decision support system to provide health officials with useful meteorological information. ``By targeting forecasts in regions where meningitis is a threat, we may be able to help vulnerable populations. Ultimately, we hope to build on this project and provide information to public health programs battling weather-related diseases in other parts of the world,'' said Rajul Pandya, director of UCAR's Community Building Program. Funding for the project comes from a $900,000 grant from Google.org, the philanthropic arm of the Internet search company.

  3. [Counterfeit medicines: a growing threat].

    Science.gov (United States)

    Barbereau, S

    2006-12-01

    The medical drug market has undergone considerable transformation in recent years. Like other products, medicines have been affected by globalization. Free trade policies have had a number of negative effects including a reduction in quality control not only for some products but also for raw materials and finished products. The global environment has also created conditions conducive to counterfeit medicines. The term counterfeit medicine is defined differently from one country to another in terms of quality, legality and fraudulent intent. This situation prompted the WHO to propose the following definition: "A counterfeit medicine is one which is deliberately and fraudulently mislabeled with respect to identity and/or source. Counterfeiting can apply to both branded and generic products and counterfeit products may include products with the correct ingredients or with the wrong ingredients, without active ingredients, with insufficient active ingredients or with fake packaging." Weak pharmaceutical regulation often compounded by widespread corruption in developing countries has greatly facilitated the development of this illicit market with harmful and costly effects on public health. Due to the lack of pharmocovigilance accidents involving use of counterfeit drugs go unreported. For this reason it is not possible to measure the economic impact. While counterfeiting has become a major threat in developing countries, it also affects industrialized countries. Fraudulent behavior occurs all over the world.

  4. Terrorism threats and preparedness in Canada: the perspective of the Canadian public.

    Science.gov (United States)

    Gibson, Stacey; Lemyre, Louise; Clément, Mélanie; Markon, Marie-Pierre L; Lee, Jennifer E C

    2007-06-01

    Although Canada has not experienced a major terrorist attack, an increased global pending threat has put preparedness at the top of the Canadian government's agenda. Given its strong multicultural community and close proximity to the recently targeted United States, the Canadian experience is unique. However, minimal research exists on the public's reactions to terrorism threats and related preparedness strategies. In order for response initiatives to be optimally effective, it is important that the public's opinions regarding terrorism and preparedness be considered. This qualitative study examined perceptions of terrorism threats among Canadians living in Central and Eastern Canada (N = 75) in the fall of 2004. Conceptualizations of terrorism threat, psychosocial impacts, and sense of preparedness were explored in a series of qualitative interviews. Findings revealed that the majority of Canadians did not feel overly threatened by terrorist attacks, due in part to a perception of terrorist threats as related to global sociopolitical events and a positive Canadian identity. In addition, while most respondents did not feel they were individually affected by the threat of terrorism, there was some concern regarding larger societal impacts, such as increased paranoia, discrimination, and threats to civil liberties. Participants' views on preparedness focused largely on the utility of emergency preparedness strategies and the factors that could mitigate or inhibit preparedness at the individual and institutional levels, with a specific focus on education. Finally, the significant relevance of these findings in shaping terrorism preparedness, both in Canada and generally, is discussed.

  5. Towards securing SCADA systems against process-related threats

    NARCIS (Netherlands)

    Hadziosmanovic, Dina; Bolzoni, Damiano; Hartel, Pieter

    2010-01-01

    We propose a tool-assisted approach to address process-related threats on SCADA systems. Process-related threats have not been addressed before in a systematic manner. Our approach consists of two steps: threat analysis and threat mitigation. For the threat analysis, we combine two methodologies (PH

  6. Forecasting Lightning Threat Using WRF Proxy Fields

    Science.gov (United States)

    McCaul, E. W., Jr.

    2010-01-01

    Objectives: Given that high-resolution WRF forecasts can capture the character of convective outbreaks, we seek to: 1. Create WRF forecasts of LTG threat (1-24 h), based on 2 proxy fields from explicitly simulated convection: - graupel flux near -15 C (captures LTG time variability) - vertically integrated ice (captures LTG threat area). 2. Calibrate each threat to yield accurate quantitative peak flash rate densities. 3. Also evaluate threats for areal coverage, time variability. 4. Blend threats to optimize results. 5. Examine sensitivity to model mesh, microphysics. Methods: 1. Use high-resolution 2-km WRF simulations to prognose convection for a diverse series of selected case studies. 2. Evaluate graupel fluxes; vertically integrated ice (VII). 3. Calibrate WRF LTG proxies using peak total LTG flash rate densities from NALMA; relationships look linear, with regression line passing through origin. 4. Truncate low threat values to make threat areal coverage match NALMA flash extent density obs. 5. Blend proxies to achieve optimal performance 6. Study CAPS 4-km ensembles to evaluate sensitivities.

  7. Emerging oomycete threats to plants and animals.

    Science.gov (United States)

    Derevnina, Lida; Petre, Benjamin; Kellner, Ronny; Dagdas, Yasin F; Sarowar, Mohammad Nasif; Giannakopoulou, Artemis; De la Concepcion, Juan Carlos; Chaparro-Garcia, Angela; Pennington, Helen G; van West, Pieter; Kamoun, Sophien

    2016-12-05

    Oomycetes, or water moulds, are fungal-like organisms phylogenetically related to algae. They cause devastating diseases in both plants and animals. Here, we describe seven oomycete species that are emerging or re-emerging threats to agriculture, horticulture, aquaculture and natural ecosystems. They include the plant pathogens Phytophthora infestans, Phytophthora palmivora, Phytophthora ramorum, Plasmopara obducens, and the animal pathogens Aphanomyces invadans, Saprolegnia parasitica and Halioticida noduliformans For each species, we describe its pathology, importance and impact, discuss why it is an emerging threat and briefly review current research activities.This article is part of the themed issue 'Tackling emerging fungal threats to animal health, food security and ecosystem resilience'.

  8. THE BIOTERRORISM THREAT: TECHNOLOGICAL AND POLITICAL CONSIDERATIONS

    Energy Technology Data Exchange (ETDEWEB)

    J. F. PILAT

    2000-03-01

    Bioterrorism--along with biowarfare, from which it may not always be distinguishable in practice--will be a feature of the strategic landscape in the 21st century and is high on the US national security agenda. Bioterrorism poses a potential threat to the US population, agriculture, interests, friends and allies, and military forces (asymmetric threats). Yet these possibilities have not been widely pursued or realized by terrorists. The perceived threat is far worse than anything experienced to date, and is largely technologically driven.

  9. Identity threat and stigma in cancer patients

    Directory of Open Access Journals (Sweden)

    Sarah Knapp

    2014-09-01

    Full Text Available Cancer stigma has undergone an important transformation in recent decades. In general, this disease no longer fits squarely into Goffman’s classic taxonomy of stigmatized conditions. This review will demonstrate that, with important adaptations, an identity-threat model of stigma can be used to organize cancer stigma research post-Goffman. This adapted model postulates that one’s personal attributions, responses to situational threat, and disease/treatment characteristics can be used to predict identity threat and well-being of individuals with cancer. Implications for further research and clinical practice are discussed.

  10. Sahara Coal Pressure Filter ditch optimize operational efifciency%哈拉沟选煤厂加压过滤机运行效率优化

    Institute of Scientific and Technical Information of China (English)

    李兴华; 蒋淑丽; 马敬坡

    2015-01-01

    针对哈拉沟选煤厂细煤泥含量大,细煤泥水分高,加压过滤机小时处理量达不到设计要求等问题,通过改善哈拉沟选煤厂的细煤泥处理设备即加压过滤机的入料性质、运行参数、工艺系统等方法,提出了解决方案。%aiming Sahara Coal ditch fine slime content of large, thin slime high moisture, pressure filter hour processing capacity of less than the design requirements and other issues, by improving the Sahara Coal ditch ifne slime treatment equipment that pressure filter feed properties, operating parameters, process systems and other methods proposed solutions.

  11. A study of the relict fish fauna of northern Chad, with the first records of a polypterid and a poeciliid in the Sahara desert.

    Science.gov (United States)

    Trape, Sébastien

    2013-01-01

    Seventeen species and sub-species of fishes belonging to four families (Cyprinidae, Clariidae, Aplocheilidae, Cichlidae) were known to occur in perennial bodies of water in the Sahara desert. The study of fishes collected in Lake Boukou near Ounianga Serir (Borkou, northern Chad) shows, for the first time, the occurrence in the Sahara desert of relict populations of Polypterus senegalus (Polypteridae) and Poropanchax normani (Poeciliidae). The Cichlidae Tilapia zilli was also collected in this lake. With these new records, the relict fish fauna currently known in lakes and gueltas of the Borkou plateaus comprises six species. In the Ennedi Mountains, where the specific status of Barbus populations was unclear, B. macrops was collected in Bachikere guelta. The toad Amietophrynus regularis was collected in Ounianga Kebir.

  12. Cyber threats in social networking websites

    CERN Document Server

    Gharibi, Wajeb

    2012-01-01

    A social network is a social structure made up of individuals or organizations called nodes, which are connected by one or more specific types of interdependency, such as friendship, common interest, and exchange of finance, relationships of beliefs, knowledge or prestige. A cyber threat can be both unintentional and intentional, targeted or non targeted, and it can come from a variety of sources, including foreign nations engaged in espionage and information warfare, criminals, hackers, virus writers, disgruntled employees and contractors working within an organization. Social networking sites are not only to communicate or interact with other people globally, but also one effective way for business promotion. In this paper, we investigate and study the cyber threats in social networking websites. We go through the amassing history of online social websites, classify their types and also discuss the cyber threats, suggest the anti-threats strategies and visualize the future trends of such hoppy popular websi...

  13. Advanced Insider Threat Mitigation Workshop Instructional Materials

    Energy Technology Data Exchange (ETDEWEB)

    Gibbs, Philip [Brookhaven National Lab. (BNL), Upton, NY (United States); Larsen, Robert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); O' Brien, Mike [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Edmunds, Tom [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2009-02-01

    Insiders represent a formidable threat to nuclear facilities. This set of workshop materials covers methodologies to analyze and approaches to mitigate the threat of an insider attempting abrupt and protracted theft of nuclear materials. This particular set of materials is an update of a January 2008 version to add increased emphasis on Material Control and Accounting and its role with respect to protracted insider nuclear material theft scenarios. This report is a compilation of workshop materials consisting of lectures on technical and administrative measures used in Physical Protection (PP) and Material Control and Accounting (MC&A) and methods for analyzing their effectiveness against a postulated insider threat. The postulated threat includes both abrupt and protracted theft scenarios. Presentation is envisioned to be through classroom instruction and discussion. Several practical and group exercises are included for demonstration and application of the analysis approach contained in the lecture/discussion sessions as applied to a hypothetical nuclear facility.

  14. Childhood maltreatment and threats with weapons.

    Science.gov (United States)

    Casiano, Hygiea; Mota, Natalie; Afifi, Tracie O; Enns, Murray W; Sareen, Jitender

    2009-11-01

    The relationship between childhood maltreatment and future threats with weapons is unknown. We examined data from the nationally representative National Comorbidity Survey Replication (n = 5692) and conducted multiple logistic regression analyses to determine the association between childhood maltreatment and lifetime behavior of threatening others with a gun or other weapon. After adjusting for sociodemographic variables, physical abuse, sexual abuse, and witnessing domestic violence were significantly associated with threats made with a gun (adjusted odds ratios [AOR] ranging between 3.38 and 4.07) and other weapons (AOR ranging between 2.16 and 2.83). The greater the number of types of maltreatment experienced, the stronger the association with lifetime threats made to others with guns and any weapons. Over 94% of respondents who experienced maltreatment and made threats reported that the maltreatment occurred prior to threatening others with weapons. Prevention efforts that reduce exposure to maltreatment may reduce violent behavior in later life.

  15. Need threat can motivate performance after ostracism.

    Science.gov (United States)

    Jamieson, Jeremy P; Harkins, Stephen G; Williams, Kipling D

    2010-05-01

    Ostracism threatens fundamental needs of belonging, self-esteem, control, and meaningful existence, which should motivate participants to respond to this threat. However, research has yet to examine the role of need threat in producing motivation after ostracism. In the current work, participants completed a "cognitive ability" (antisaccade) task following Cyberball-induced ostracism or inclusion. In two experiments, it was found that when ostracized, participants do not see antisaccade performance as a means of responding to the concerns produced by need threat; they respond only to the social threat, leading to worse performance than included participants (Experiments 1 and 2). However, when participants see an avenue of response (the Cyberball players can compare antisaccade performances), ostracized participants outperform included participants (Experiment 2). Moreover, this effect was mediated by the need for belonging, suggesting that ostracized participants were motivated to elevate their inclusionary status by demonstrating their worth on the cognitive ability task.

  16. Cyber Threats In Social Networking Websites

    Directory of Open Access Journals (Sweden)

    Wajeb Ghari

    2012-02-01

    Full Text Available A social network is a social structure made up of individuals or organizations called nodes, which areconnected by one or more specific types of interdependency, such as friendship, common interest, and exchange of finance, relationships of beliefs, knowledge or prestige. A cyber threat can be both unintentional and intentional, targeted or non targeted, and it can come from a variety of sources, including foreign nations engaged in espionage and information warfare, criminals, hackers, virus writers, disgruntled employees and contractors working within an organization. Social networking sitesare not only to communicate or interact with other people globally, but also one effective way for business promotion. In this paper, we investigate and study the cyber threats in social networking websites. We go through the amassing history of online social websites, classify their types and also discuss the cyber threats, suggest the anti-threats strategies and visualize the future trends of such hoppy popular websites.

  17. Advanced insider threat mitigation workshop instructional materials

    Energy Technology Data Exchange (ETDEWEB)

    Gibbs, Philip [Brookhaven National Lab. (BNL), Upton, NY (United States); Larsen, Robert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); O Brien, Mike [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Edmunds, Tom [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2008-11-01

    Insiders represent a formidable threat to nuclear facilities. This set of workshop materials covers methodologies to analyze and approaches to mitigate the threat of an insider attempting abrupt and protracted theft of nuclear materials. This particular set of materials is a n update of a January 2008 version to add increased emphasis on Material Control and Accounting and its role with respect to protracted insider nuclear material theft scenarios.

  18. The concept of ego threat in social and personality psychology: is ego threat a viable scientific construct?

    Science.gov (United States)

    Leary, Mark R; Terry, Meredith L; Batts Allen, Ashley; Tate, Eleanor B

    2009-08-01

    Although widely invoked as an explanation for psychological phenomena, ego threat has been conceptualized and induced in a variety of ways. Most contemporary research conceptualizes ego threat as a threat to a person's self-image or self-esteem, but experimental operationalizations of ego threat usually confound threats to self-esteem with threats to public image or decreased control over negative events, leading to an inability to distinguish the effects of threats to people's personal egos from threats to public image or threats to feelings of control. This article reviews research on ego threat, discusses experimental manipulations that confound ego threat with other processes, and makes recommendations regarding the use of ego threat as a construct in personality and social psychology.

  19. Nuclear Threat Intelligence, Surveillance, and Reconnaissance

    Science.gov (United States)

    Kuliasha, Michael

    2012-03-01

    The National Security Strategy states that the greatest threat to the American people is ``the pursuit of nuclear weapons by violent extremists and their proliferation to additional states.'' The Global Nuclear Detection Architecture (GNDA) addresses a key portion of that threat by focusing on detecting nuclear and radiological materials that are out of regulatory control within permissive operating environments. However, the force protection requirements of the Department of Defense (DoD) range across a wider mission space from permissive environments, where nuclear and radiological materials can be monitored while under regulatory control, to hostile environments where nuclear and radiological materials exist in defiance of international regulations and agreements. This wider range of operating environments and the inherent physics limitations on the range of radiation detection pose great challenges to radiation detection-focused approaches to nuclear threat detection. Consequently, DoD is in the process of defining an intelligence, surveillance, and reconnaissance approach to countering nuclear threats that considers the observable signatures of all elements that comprise a potential threat; information, funds, people, material, equipment, and infrastructure. This strategy represents a shift from radiation detection as the primary sensing modality to radiation detection as one of many sensing modalities, including the human dimension, with a heavy emphasis on data fusion. This presentation will describe the attributes of a layered sensing approach to nuclear threat detection, illustrate the approach with examples, define potential building blocks, and discuss technical challenges.

  20. Friendship Characteristics, Threat Appraisals, and Varieties of Jealousy About Romantic Partners’ Friendships

    Directory of Open Access Journals (Sweden)

    Timothy R. Worley

    2014-12-01

    Full Text Available This study examined the role of friendship sex composition, friendship history, and threat appraisals in the experience of jealousy about a romantic partner’s involvement in extradyadic friendships. Using a survey, 201 individuals responded to scenarios describing a romantic partner’s involvement in a significant friendship outside the romantic dyad. A partner’s involvement in a cross-sex friendship was associated with greater perceptions of threat to both the existence and quality of the romantic relationship than was a partner’s involvement in a same-sex friendship. Further, the specific forms of jealousy experienced about partners’ friendships were dependent on the threat appraisals individuals associated with the friendships. Appraisals of relational existence threat mediated the influence of friendship characteristics (i.e., sex composition and history on sexual jealousy and companionship jealousy, while appraisals of relational quality threat mediated the influence of friendship characteristics on intimacy jealousy, power jealousy, and companionship jealousy. This study points toward the central role of threat appraisals in mediating associations between rival characteristics and various forms of jealousy about a partner’s friendships.

  1. Marine ground intelligence reform: how to redesign ground intelligence for the threats of the 21st century

    OpenAIRE

    1997-01-01

    Approved for public release; distribution is unlimited Present-day Marine ground intelligence is configured for attrition warfighting and the predictable conventional adversaries of the past. Designed during WWII, it has undergone little change; what has changed is the threat environment. Modern-day threats are less centralized and regimented. They think on their own and they adapt quickly. This thesis analyzes the current configuration of Marine ground intelligence and compares it with tw...

  2. Electricity from the Sahara and hydropower - moving forward with renewable energies; Saharastrom und Wasserkraft - mit erneuerbaren Energien in die Zukunft

    Energy Technology Data Exchange (ETDEWEB)

    Kolle, Christian (comp.)

    2009-07-01

    On 13 July a launch meeting took place under the auspices of Muenchner Rueck to initiate the largest private green electricity project of all times. Twenty German companies are preparing themselves to participate in the construction of photovoltaic systems and solar power plants in the Sahara. Even the technical problem of transporting the electricity to Europe, hitherto an obstacle to profitability, seems to have been brought to a solution. The following information was sourced from the GESIS databases SOLIS and SOFIS and the six English-language databases of the producer Cambridge Scientific Abstracts (CSA) which are integrated in www.sowiport.de via the national licences. The SOLIS database mostly covers German-language publications, i.e. journal contributions, monographies as well as contributions to compilations in the major social sciences. SOFIS largely procures its information through surveys among institutions in German speaking countries where social science research is conducted. The CSA databases offer references to research results centering on sociology and political science as well as neighbouring disciplines in the social and economic sciences. They largely cover international journals, but also books, book chapters and in some cases publication reviews.

  3. Implementation of triple helix clusters procedure in the sub-Sahara Africa energy sector. Case study: Academia - CREEC Photovoltaic Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Da Silva, Izael [Makerere Univ., Kampala (UG). Centre for Research in Energy and Energy Conservation (CREEC)

    2011-07-01

    Penetration of decentralized power supply for households and commercial enterprises is low in Sub-Sahara Africa. Solar Home Systems (SHS), despite their widespread use in other continents have failed to attain much success in Africa. One of the reasons is the high rate of failure of existing implementations. Data shows earlier failure rates of 50%. This is largely attributed to poor quality of products used, inefficient installation, mismanagement and lack of maintenance. To address this problem, the Centre for Research in Energy and Energy Conservation (CREEC) is setting up a Solar PV test laboratory in Uganda. This paper describes the installation process and how to sustain the laboratory after implementation. The lab is intended to provide a forum for training, research and consultancy under CREEC. It is intended as a tool to implement the triple helix and clusters procedure in the PV industry in particular and the energy sector in a more general scope. This paper offers details covering the current situation of the energy sector in Uganda and how the lab supports capacity building in the university to support the upcoming demand. (orig.)

  4. Holocene freshwater carbonate structures in the hyper-arid Gebel Uweinat region of the Sahara Desert (Southwestern Egypt)

    Science.gov (United States)

    Marinova, Margarita M.; Meckler, A. Nele; McKay, Christopher P.

    2014-01-01

    The eastern part of the Sahara is at present the driest region of the desert. Yet the extensive animal rock art in the area, presumed to depict real activities in the lives of the painters, suggests that environmental conditions were significantly different when the rock art was produced. Here we report on exploration of the area, which led to the discovery of morphologically-distinct carbonate structures that line the walls of two valleys in Gebel Uweinat, and were likely formed in standing water. The carbonate structures comprise what appear to be shoreline carbonate formations, and date back to 8100 and 9400 years BP. The chemical and morphological similarity of these formations to carbonate structures from modern lakes suggests that these lakes contained fresh, standing water suitable for human and animal use. However, the significant quartz content suggests that windblown sand was pervasive, and thus the vegetation cover may have been sparse. This discovery supports the possibility of grasslands in the area, which may have been able to support human habitation, and adds to the evidence for a wetter climate in the area in the early Holocene.

  5. Impacts of the Sahel-Sahara Interface Reforestation on West African Climate: Intraseasonal Variability and Extreme Precipitation Events

    Directory of Open Access Journals (Sweden)

    Ibrahima Diba

    2016-01-01

    Full Text Available This study aims to evaluate the impacts of the Sahel-Sahara interface reforestation on spatiotemporal variability of the summer rainfall and extreme precipitation events over West Africa using the RegCM4 model. The land surface scheme of RegCM4 was modified to incorporate an East-West reforested zone (15°N and 20°N. Two runs were performed using the standard version of RegCM4 and the modified one of the same model taking into account the incorporated forest. The reforestation significantly modifies rainfall signal over West Africa by increasing it over the reforested zone and the Fouta Jallon highlands (FJH. This rainfall increase is associated with a strengthening of the atmospheric moisture over the reforested area. This atmospheric moisture content increase associated with the wind dynamic may explain the spatiotemporal change of the rainfall and extreme precipitation events. The analysis of the impacts of the reforestation on some rainfall indices shows an increase of the 90th, 95th, and 99th percentiles over the reforested zone and off the FJH. This reforestation also causes an increase of the maximum length of the consecutive wet days over and off FJH and a decrease of the maximum length of the consecutive dry days over the northern Sahel and the reforested zone.

  6. A Review of e-Health Interventions for Maternal and Child Health in Sub-Sahara Africa.

    Science.gov (United States)

    Obasola, Oluwaseun Ireti; Mabawonku, Iyabo; Lagunju, Ikeoluwa

    2015-08-01

    To review e-health interventions for maternal and child health (MCH) and to explore their influence on MCH practices in sub-Sahara Africa (SSA). Keyword searches were used to retrieve articles from four databases and the websites of organisations involved in e-health projects for MCH in SSA. A total of 18relevant articles were retrieved using inclusion and exclusion criteria. The researchers reveal the prevalence of the application of mobile phones for MCH care and the influence of the use of information and communication technology (ICT) for delivering MCH information and services to target populations. There is a need to move the application of ICT for MCH care from pilot initiatives to interventions involving all stakeholders on a sub-regional scale. These interventions should also adopt an integrated approach that takes care of the information needs at every stage along the continuum of care. It is anticipated that the study would be useful in the evolution and implementation of future ICT-based programmes for MCH in the region.

  7. Metal Poisoning: Threat and Management

    Directory of Open Access Journals (Sweden)

    SJS Flora

    2009-12-01

    Full Text Available Exposure to toxic metals remains a wide spread occupational and environmental problems in world. Due to their widespread use in human activities such as industry, agriculture and even as medicine numerous health risks may be associated with exposure to these substances. Lead, arsenic and cadmium generally interferes with a number of body functions such as the haematopoietic system, central nervous system (CNS, liver and kidneys. Over the past few decades there have been growing awareness and concern that the toxic biochemical and functional effects are occurring at lower level of metal exposure than those that produce overt clinical and pathological signs and symptoms. Despite many years of research we are still far from an effective treatment of chronic heavy metal poisoning. The main therapeutic option for chronic metal poisoning relies in chelation therapy. Chelating agents are capable of linking together metal ions to form complex structures which can be easily excreted from the body. They have been used clinically as antidotes for acute and chronic poisoning. 2, 3-dimercaprol (BAL has long been the mainstay of chelation therapy of lead or arsenic poisoning. Meso 2, 3, -dimercaptosuccinic acid (DMSA has been tried successfully in animals as well as in few cases of human lead or arsenic poisoning. However, one of the major disadvantages of chelation with DMSA has been its inability to remove heavy metal from the intracellular sites because of its lipophobic nature. Further, it does not provide protection in terms of clinical/ biochemical recovery. A new trend in chelation therapy has emerged to use combined treatment. This includes use of structurally different chelating agents or a combination of an antioxidant and a chelator to provide better clinical/biochemical recovery in addition to mobilization of heavy metal form intracellular sites. The present review article attempts to provide update information about the current strategies being

  8. Improving Visual Threat Detection: Research to Validate the Threat Detection Skills Trainer

    Science.gov (United States)

    2013-08-01

    above, these responses included: • “The unsettled dirt,” • “ Grassy area,” and • “Weapons not held properly.” We hypothesized that training would...alternative explanation is that with training, participants narrow their choices to threat relevant cues rather than identifying all possible threats

  9. 49 CFR 1544.303 - Bomb or air piracy threats.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 9 2010-10-01 2010-10-01 false Bomb or air piracy threats. 1544.303 Section 1544... AND COMMERCIAL OPERATORS Threat and Threat Response § 1544.303 Bomb or air piracy threats. (a) Flight... upon receiving information that an act or suspected act of air piracy has been committed, the...

  10. 49 CFR 1546.301 - Bomb or air piracy threats.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 9 2010-10-01 2010-10-01 false Bomb or air piracy threats. 1546.301 Section 1546... Threat Response § 1546.301 Bomb or air piracy threats. No foreign air carrier may land or take off an airplane in the United States after receiving a bomb or air piracy threat against that airplane, unless...

  11. Threat assessment and sensor management in a modular architecture

    Science.gov (United States)

    Page, S. F.; Oldfield, J. P.; Islip, S.; Benfold, B.; Brandon, R.; Thomas, P. A.; Stubbins, D. J.

    2016-10-01

    Many existing asset/area protection systems, for example those deployed to protect critical national infrastructure, are comprised of multiple sensors such as EO/IR, radar, and Perimeter Intrusion Detection Systems (PIDS), loosely integrated with a central Command and Control (C2) system. Whilst some sensors provide automatic event detection and C2 systems commonly provide rudimentary multi-sensor rule based alerting, the performance of such systems is limited by the lack of deep integration and autonomy. As a result, these systems have a high degree of operator burden. To address these challenges, an architectural concept termed "SAPIENT" was conceived. SAPIENT is based on multiple Autonomous Sensor Modules (ASMs) connected to a High-Level Decision Making Module (HLDMM) that provides data fusion, situational awareness, alerting, and sensor management capability. The aim of the SAPIENT concept is to allow for the creation of a surveillance system, in a modular plug-and-play manner, that provides high levels of autonomy, threat detection performance, and reduced operator burden. This paper considers the challenges associated with developing an HLDMM aligned with the SAPIENT concept, through the discussion of the design of a realised HLDMM. Particular focus is drawn to how high levels of system level performance can be achieved whilst retaining modularity and flexibility. A number of key aspects of our HLDMM are presented, including an integrated threat assessment and sensor management framework, threat sequence matching, and ASM trust modelling. The results of real-world testing of the HLDMM, in conjunction with multiple Laser, Radar, and EO/IR sensors, in representative semi-urban environments, are discussed.

  12. Insider Threat Assessment: Model, Analysis and Tool

    Science.gov (United States)

    Chinchani, Ramkumar; Ha, Duc; Iyer, Anusha; Ngo, Hung Q.; Upadhyaya, Shambhu

    Insider threat is typically attributed to legitimate users who maliciously leverage their system privileges, and familiarity and proximity to their computational environment to compromise valuable information or inflict damage. According to the annual CSI/FBI surveys conducted since 1996, internal attacks and insider abuse form a significant portion of reported incidents. The strongest indication yet that insider threat is very real is given by the recent study [2] jointly conducted by CERT and the US Secret Service; the first of its kind, which provides an in-depth insight into the problem in a real-world setting. However, there is no known body of work which addresses this problem effectively. There are several challenges, beginning with understanding the threat.

  13. Left-Wing Extremism: The Current Threat

    Energy Technology Data Exchange (ETDEWEB)

    Karl A. Seger

    2001-04-30

    Left-wing extremism is ''alive and well'' both in the US and internationally. Although the current domestic terrorist threat within the U. S. is focused on right-wing extremists, left-wing extremists are also active and have several objectives. Leftist extremists also pose an espionage threat to U.S. interests. While the threat to the U.S. government from leftist extremists has decreased in the past decade, it has not disappeared. There are individuals and organizations within the U.S. who maintain the same ideology that resulted in the growth of left-wing terrorism in this country in the 1970s and 1980s. Some of the leaders from that era are still communicating from Cuba with their followers in the U.S., and new leaders and groups are emerging.

  14. Epidemiology today: Mitigating threats to an ecosystem.

    Science.gov (United States)

    Kreiger, Nancy

    2016-06-27

    Ecosystems comprise all the living and non-living things in a particular area (e.g., rain forest, desert), which interact and maintain equilibrium. Loss of equilibrium (e.g., clear-cutting trees in a rain forest) can mean the decline of the ecosystem, unless it is able to adapt to the new circumstances. The term "knowledge ecosystem" describes an approach to managing knowledge in a particular field; the components of this system include the people, the technological skills and resources, and information or data. Epidemiology can be thought of as a knowledge ecosystem and, like ecological systems, its existence can be threatened, from both internal and external forces that may alter its equilibrium. This paper describes some threats to the epidemiology knowledge ecosystem, how these threats came about, and what responses we can make that may serve to mitigate those threats.

  15. GLOBAL WARMING: IS A NEW THREAT?

    Energy Technology Data Exchange (ETDEWEB)

    Ayca Eminoglu

    2008-09-30

    In the Post Cold War era, the concepts of ''security'', ''national security'', and ''international security'' have changed with regard to their contents and meanings. Such developments made states to renew their national security policies. Security is a special form of politics as well. All security issues are political problems but not all political conflicts are security issues. In the Post Cold War era, differentiating and increasing numbers of elements that constitutes threat changed the concept of threat and widen the capacity of security. In this term, many elements lost its effect of being a threat but also new threatening elements emerged. Environmental problems, human rights, mass migration, micro nationalism, ethnic conflicts, religious fundamentalism, contagious diseases, international terrorism, economic instabilities, drug and weapon smuggling and human trafficking are the new problems emerged in international security agenda. Environmental problems no longer take place in security issues and can be mentioned as a ''low security'' issue. They are threats to the global commons i.e. the oceans, the seas, the ozone layer and the climate system, which are life supports for mankind as a whole. Global warming is one of the most important environmental issues of our day that effects human life in every field and can be defined as a 'serious threat to international security'. Because of global warming, environmental changes will occur and these changes will cause conflicting issues in international relations. Because of global warming dwindling freshwater supplies, food shortages, political instability and other conflicts may take place. Some IR scholars see a need for global cooperation in order to face the threat. At the background of global warming and its effects, states have to get preventive measures and normally, each state form its own measures, therefore as a

  16. Bio-Terrorism Threat and Casualty Prevention

    Energy Technology Data Exchange (ETDEWEB)

    NOEL,WILLIAM P.

    2000-01-01

    The bio-terrorism threat has become the ''poor man's'' nuclear weapon. The ease of manufacture and dissemination has allowed an organization with only rudimentary skills and equipment to pose a significant threat with high consequences. This report will analyze some of the most likely agents that would be used, the ease of manufacture, the ease of dissemination and what characteristics of the public health response that are particularly important to the successful characterization of a high consequence event to prevent excessive causalities.

  17. Bioterrorism: is it a real threat?

    Science.gov (United States)

    Gottschalk, René; Preiser, Wolfgang

    2005-05-01

    The Geneva Protocol of 1925 commits the signatory nations to refraining from the use of biological weapons. However, the terrorist assaults of September 2001 and, subsequently, the anthrax-containing letters are cause for great concerns: new threats to the security of nations are expected, as terrorist organizations seem to increasingly explore novel ways of spreading terror. In this context, naturally emerging diseases such as SARS, monkeypox or West Nile fever assume new importance because it is difficult to distinguish between natural epidemics and possible bioweapon assaults. Great efforts on the part of governments and public health authorities are necessary to counteract these threats.

  18. Nash bargaining with a nondeterministic threat

    CERN Document Server

    Soileau, Kerry Michael

    2008-01-01

    We consider bargaining problems which involve two participants, with a nonempty closed, bounded convex bargaining set of points in the real plane representing all realizable bargains. We also assume that there is no definite threat or disagreement point which will provide the default bargain if the players cannot agree on some point in the bargaining set. However, there is a nondeterministic threat: if the players fail to agree on a bargain, one of them will be chosen at random with equal probability, and that chosen player will select any realizable bargain as the solution, subject to a reasonable restriction.

  19. Defending Against Advanced Persistent Threats Using Game-Theory.

    Science.gov (United States)

    Rass, Stefan; König, Sandra; Schauer, Stefan

    2017-01-01

    Advanced persistent threats (APT) combine a variety of different attack forms ranging from social engineering to technical exploits. The diversity and usual stealthiness of APT turns them into a central problem of contemporary practical system security, since information on attacks, the current system status or the attacker's incentives is often vague, uncertain and in many cases even unavailable. Game theory is a natural approach to model the conflict between the attacker and the defender, and this work investigates a generalized class of matrix games as a risk mitigation tool for an advanced persistent threat (APT) defense. Unlike standard game and decision theory, our model is tailored to capture and handle the full uncertainty that is immanent to APTs, such as disagreement among qualitative expert risk assessments, unknown adversarial incentives and uncertainty about the current system state (in terms of how deeply the attacker may have penetrated into the system's protective shells already). Practically, game-theoretic APT models can be derived straightforwardly from topological vulnerability analysis, together with risk assessments as they are done in common risk management standards like the ISO 31000 family. Theoretically, these models come with different properties than classical game theoretic models, whose technical solution presented in this work may be of independent interest.

  20. Defending Against Advanced Persistent Threats Using Game-Theory

    Science.gov (United States)

    König, Sandra; Schauer, Stefan

    2017-01-01

    Advanced persistent threats (APT) combine a variety of different attack forms ranging from social engineering to technical exploits. The diversity and usual stealthiness of APT turns them into a central problem of contemporary practical system security, since information on attacks, the current system status or the attacker’s incentives is often vague, uncertain and in many cases even unavailable. Game theory is a natural approach to model the conflict between the attacker and the defender, and this work investigates a generalized class of matrix games as a risk mitigation tool for an advanced persistent threat (APT) defense. Unlike standard game and decision theory, our model is tailored to capture and handle the full uncertainty that is immanent to APTs, such as disagreement among qualitative expert risk assessments, unknown adversarial incentives and uncertainty about the current system state (in terms of how deeply the attacker may have penetrated into the system’s protective shells already). Practically, game-theoretic APT models can be derived straightforwardly from topological vulnerability analysis, together with risk assessments as they are done in common risk management standards like the ISO 31000 family. Theoretically, these models come with different properties than classical game theoretic models, whose technical solution presented in this work may be of independent interest. PMID:28045922

  1. Defensive activation to (un)predictable interoceptive threat: The NPU respiratory threat test (NPUr).

    Science.gov (United States)

    Schroijen, Mathias; Fantoni, Simona; Rivera, Carmen; Vervliet, Bram; Schruers, Koen; van den Bergh, Omer; van Diest, Ilse

    2016-06-01

    Potentially life-threatening interoceptive sensations easily engage the behavioral defensive system. Resulting fear and anxiety toward interoceptive threat are functionally distinct states that are hypothesized to play a prominent role in the etiology of panic disorder. The present study aimed to investigate whether fear- and anxiety-potentiated startle responses occur to predictable and unpredictable interoceptive threat, respectively. Therefore, we modified the NPU threat test (Schmitz & Grillon, ) and replaced the aversive electrocutaneous stimulus with an aversive interoceptive stimulus (a breathing occlusion, making it briefly impossible to breathe). Healthy participants (N = 48) underwent three instructed conditions. A visual cue signaled the occlusion in the predictable condition (P), whereas another cue was unrelated to the occurrence of the occlusion in the unpredictable condition (U). The safe condition (N) also had a visual cue, but no occlusion. Both fear- and anxiety-potentiated startle blink responses were observed in response to predictable and unpredictable respiratory threat, respectively. The current study presents and validates the NPU respiratory threat test (NPUr) as an ecologically valid paradigm to study both anxiety and fear in response to a panic-relevant interoceptive threat. The paradigm allows future testing of contextual generalization, investigation of different clinical groups, and more explicit comparisons of defensive responding to interoceptive versus exteroceptive threats.

  2. OpenFlow Security Threat Detection and Defense Services

    Directory of Open Access Journals (Sweden)

    Wanqing You

    2014-11-01

    Full Text Available The emergence of OpenFlow-capable switches de- couples control plane from the data flow plane so that they support programmable network and allow network administrators to have programmable central control of network traffic via a controller. The controller and its communication with switches and users become a malicious attack target. This paper explores major possible security threats and attacks on the controller of SDN and proposes a new approach to automatically and dynamically detect and monitor malicious behaviors on flow message passing and defend such attacks to ensure the security of SDN. We have built a FlowEye prototype at service level on Mininet API, and simulation tests are done on two feasible attacks on OpenFlow Beacon platform. The paper provides the feasibility study of such attacks and defense protection strategies in SDN security research.

  3. Using the threat probability task to assess anxiety and fear during uncertain and certain threat.

    Science.gov (United States)

    Bradford, Daniel E; Magruder, Katherine P; Korhumel, Rachel A; Curtin, John J

    2014-09-12

    Fear of certain threat and anxiety about uncertain threat are distinct emotions with unique behavioral, cognitive-attentional, and neuroanatomical components. Both anxiety and fear can be studied in the laboratory by measuring the potentiation of the startle reflex. The startle reflex is a defensive reflex that is potentiated when an organism is threatened and the need for defense is high. The startle reflex is assessed via electromyography (EMG) in the orbicularis oculi muscle elicited by brief, intense, bursts of acoustic white noise (i.e., "startle probes"). Startle potentiation is calculated as the increase in startle response magnitude during presentation of sets of visual threat cues that signal delivery of mild electric shock relative to sets of matched cues that signal the absence of shock (no-threat cues). In the Threat Probability Task, fear is measured via startle potentiation to high probability (100% cue-contingent shock; certain) threat cues whereas anxiety is measured via startle potentiation to low probability (20% cue-contingent shock; uncertain) threat cues. Measurement of startle potentiation during the Threat Probability Task provides an objective and easily implemented alternative to assessment of negative affect via self-report or other methods (e.g., neuroimaging) that may be inappropriate or impractical for some researchers. Startle potentiation has been studied rigorously in both animals (e.g., rodents, non-human primates) and humans which facilitates animal-to-human translational research. Startle potentiation during certain and uncertain threat provides an objective measure of negative affective and distinct emotional states (fear, anxiety) to use in research on psychopathology, substance use/abuse and broadly in affective science. As such, it has been used extensively by clinical scientists interested in psychopathology etiology and by affective scientists interested in individual differences in emotion.

  4. Threats and Vulnerabilities of RFID and Beyond

    NARCIS (Netherlands)

    Hoepman, J.H.; Veugen, P.J.M.

    2009-01-01

    This chapter discusses both security and privacy threats to RFID systems, in a balanced way. We first outline the general architecture of an RFID system, the stakeholders managing the different components, and identify the specific properties of RFID systems relevant for privacy and security. We the

  5. The Missing Piece in Threat Intelligence

    Directory of Open Access Journals (Sweden)

    Frank Denis

    2016-03-01

    Full Text Available Common systems for sharing intelligence on security threats have not been designed to efficiently process feedback from infrastructure providers. In order to fill this gap, we introduce DIP, a new description language to expose changes being made on a network that are relevant to security research and prevention.

  6. Hostile Intelligence Threat U.S. Technology

    Science.gov (United States)

    1988-11-01

    Assistant Secretary of Defense for DoD 5200.1-PH-2 Command, Control, Comunnications , and Intelligence (703) 695-2686 DEPARTMENT OF DEFENSE DTIC...intelligence threat: "* PROGRAM MANAGER Telephone: "* INSTALLATION SECURITY OFFICE Telephone: "* LOCAL DIS COGNIZANT SECURITY OFFICE (Industrial

  7. Primary Auditory Cortex Regulates Threat Memory Specificity

    Science.gov (United States)

    Wigestrand, Mattis B.; Schiff, Hillary C.; Fyhn, Marianne; LeDoux, Joseph E.; Sears, Robert M.

    2017-01-01

    Distinguishing threatening from nonthreatening stimuli is essential for survival and stimulus generalization is a hallmark of anxiety disorders. While auditory threat learning produces long-lasting plasticity in primary auditory cortex (Au1), it is not clear whether such Au1 plasticity regulates memory specificity or generalization. We used…

  8. Dismount Threat Recognition through Automatic Pose Identification

    Science.gov (United States)

    2012-03-01

    camera and joint estimation software of the Kinect for Xbox 360. A threat determination is made based on the pose identified by the network. Ac- curacy...mapping produced by the Kinect sensor [3]. . . . . . . . . . . . . . . . . . . . . . . . . . . 11 2.5. Test subject and generated model. The subject is...16 3.2. Joint position estimates extracted from Kinect . Example of col- lecting orthogonal poses

  9. Antibiotic and Antimicrobial Resistance: Threat Report 2013

    Science.gov (United States)

    ... resistant Staphylococcus aureus (MRSA) [page 77] Drug-resistant Streptococcus pneumoniae [page 79] Drug-resistant tuberculosis [page 81] Microorganisms with a Threat Level of Concerning Vancomycin-resistant Staphylococcus aureus ... Streptococcus [page 87] Clindamycin-resistant Group B Streptococcus [page ...

  10. Threats and countermeasures for network security

    Science.gov (United States)

    Denning, Peter J.

    1991-01-01

    In the late 1980's, the traditional threat of anonymous break-ins to networked computers was joined by viruses and worms, multiplicative surrogates that carry out the bidding of their authors. Technologies for authentication and secrecy, supplemented by good management practices, are the principal countermeasures. Four articles on these subjects are presented.

  11. The silent threat of low genetic diversity

    Science.gov (United States)

    Hunter, Margaret E.

    2013-01-01

    Across the Caribbean, protected coastal waters have served as primary feeding and breeding grounds for the endangered Antillean manatee. Unfortunately, these same coastal waters are also a popular “habitat” for humans. In the past, the overlap between human and manatee habitat allowed for manatee hunting and threatened the survival of these gentle marine mammals. Today, however, threats are much more inadvertent and are often related to coastal development, degraded habitats and boat strikes. In the state of Florida, decades of research on the species’ biological needs have helped conservationists address threats to its survival. For example, low wake zones and boater education have protected manatees from boat strikes, and many of their critical winter refuges are now protected. The Florida population has grown steadily, thus increasing from approximately 1,200 in 1991 to more than 5,000 in 2010. It is conceivable that in Florida manatees may one day be reclassified as “threatened” rather than “endangered.” Yet, in other parts of the Caribbean, threats still loom. This includes small, isolated manatee populations found on islands that can be more susceptible to extinction and lack of genetic diversity. To ensure the species’ long-term viability, scientists have turned their sights to the overall population dynamics of manatees throughout the Caribbean. Molecular genetics has provided new insights into long-term threats the species faces. Fortunately, the emerging field of conservation genetics provides managers with tools and strategies for protecting the species’ long-term viability.

  12. Flash floods in the Sahara: a case study for the 28 January 2013 flood in Qena, Egypt

    Directory of Open Access Journals (Sweden)

    Moawad Badawy Moawad

    2016-01-01

    Full Text Available Understanding the torrential rainfall and its consequent surface runoff in the Sahara is a crucial issue for better flood protection and water management plans. This is often hampered by the lack of appropriate in situ measurements. Even now the satellite-derived rainfall suffers from great uncertainty. Thus, we adjusted the data obtained from real-time satellite rainfall coverage (HYDIS using the in situ observed rainfall (Robs. Hydro-morphological parameters were then integrated with the empirical curve number (CN approach to estimate the surface runoff in Qena, Egypt during the 28 January 2013 flash flood event. We deduced that the study area received a total precipitation (∑Rcum of ∼35.6 × 106 [mm] and a total rain volume (∑Rvol of ∼88.9 × 109 [m3] mainly from wadi Qena (89.8%. The majority of the rainfalls fell at light intensity (<2.5 [mm hr−1]. The estimated total surface runoff (∑Qsur was 26.5 × 106 mm and the total runoff volume (∑Qvol was 66.2 × 106 [m3]. The total surface transmission losses (∑Tlos were calculated as 9.1 × 106 [mm], which represents about 25.6% of the total precipitation (∑Rcum and creates substantial opportunities for alluvial aquifer recharge. The total surface runoff (∑Qsur and flood magnitude were generally low, therefore, flood influences were restricted to the destruction of some roads in Qena but no fatalities were involved, nevertheless. Most of the running water was contained by El Sail Canal and poured into the Nile River. It is expected that the applied method in this study will be helpful for our understanding and quantification of flood hydrology and contribute to better risk management plan in the arid and hyper-arid regions.

  13. Endophytic actinomycetes from spontaneous plants of Algerian Sahara: indole-3-acetic acid production and tomato plants growth promoting activity.

    Science.gov (United States)

    Goudjal, Yacine; Toumatia, Omrane; Sabaou, Nasserdine; Barakate, Mustapha; Mathieu, Florence; Zitouni, Abdelghani

    2013-10-01

    Twenty-seven endophytic actinomycete strains were isolated from five spontaneous plants well adapted to the poor sandy soil and arid climatic conditions of the Algerian Sahara. Morphological and chemotaxonomical analysis indicated that twenty-two isolates belonged to the Streptomyces genus and the remaining five were non-Streptomyces. All endophytic strains were screened for their ability to produce indole-3-acetic acid (IAA) in vitro on a chemically defined medium. Eighteen strains were able to produce IAA and the maximum production occurred with the Streptomyces sp. PT2 strain. The IAA produced was further extracted, partially purified and confirmed by thin layer chromatography (TLC) analysis. The 16S rDNA sequence analysis and phylogenetic studies indicated that strain PT2 was closely related to Streptomyces enissocaecilis NRRL B 16365(T), Streptomyces rochei NBRC 12908(T) and Streptomyces plicatus NBRC 13071(T), with 99.52 % similarity. The production of IAA was affected by cultural conditions such as temperature, pH, incubation period and L-tryptophan concentration. The highest level of IAA production (127 μg/ml) was obtained by cultivating the Streptomyces sp. PT2 strain in yeast extract-tryptone broth supplemented with 5 mg L-tryptophan/ml at pH 7 and incubated on a rotary shaker (200 rpm) at 30 °C for 5 days. Twenty-four-hour treatment of tomato cv. Marmande seeds with the supernatant culture of Streptomyces sp. PT2 that contained the crude IAA showed the maximum effect in promoting seed germination and root elongation.

  14. Intercomparison of Satellite Dust Retrieval Products over the West African Sahara During the Fennec Campaign in June 2011

    Science.gov (United States)

    Banks, J.R.; Brindley, H. E.; Flamant, C.; Garay, M. J.; Hsu, N. C.; Kalashnikova, O. V.; Klueser, L.; Sayer, A. M.

    2013-01-01

    Dust retrievals over the Sahara Desert during June 2011 from the IASI, MISR, MODIS, and SEVIRI satellite instruments are compared against each other in order to understand the strengths and weaknesses of each retrieval approach. Particular attention is paid to the effects of meteorological conditions, land surface properties, and the magnitude of the dust loading. The period of study corresponds to the time of the first Fennec intensive measurement campaign, which provides new ground-based and aircraft measurements of the dust characteristics and loading. Validation using ground-based AERONET sunphotometer data indicate that of the satellite instruments, SEVIRI is most able to retrieve dust during optically thick dust events, whereas IASI and MODIS perform better at low dust loadings. This may significantly affect observations of dust emission and the mean dust climatology. MISR and MODIS are least sensitive to variations in meteorological conditions, while SEVIRI tends to overestimate the aerosol optical depth (AOD) under moist conditions (with a bias against AERONET of 0.31), especially at low dust loadings where the AOD<1. Further comparisons are made with airborne LIDAR measurements taken during the Fennec campaign, which provide further evidence for the inferences made from the AERONET comparisons. The effect of surface properties on the retrievals is also investigated. Over elevated surfaces IASI retrieves AODs which are most consistent with AERONET observations, while the AODs retrieved by MODIS tend to be biased low. In contrast, over the least emissive surfaces IASI significantly underestimates the AOD (with a bias of -0.41), while MISR and SEVIRI show closest agreement.

  15. Crocodiles in the Sahara desert: an update of distribution, habitats and population status for conservation planning in Mauritania.

    Directory of Open Access Journals (Sweden)

    José C Brito

    Full Text Available BACKGROUND: Relict populations of Crocodylus niloticus persist in Chad, Egypt and Mauritania. Although crocodiles were widespread throughout the Sahara until the early 20(th century, increased aridity combined with human persecution led to local extinction. Knowledge on distribution, occupied habitats, population size and prey availability is scarce in most populations. This study evaluates the status of Saharan crocodiles and provides new data for Mauritania to assist conservation planning. METHODOLOGY/PRINCIPAL FINDINGS: A series of surveys in Mauritania detected crocodile presence in 78 localities dispersed across 10 river basins and most tended to be isolated within river basins. Permanent gueltas and seasonal tâmoûrts were the most common occupied habitats. Crocodile encounters ranged from one to more than 20 individuals, but in most localities less than five crocodiles were observed. Larger numbers were observed after the rainy season and during night sampling. Crocodiles were found dead in between water points along dry river-beds suggesting the occurrence of dispersal. CONCLUSION/SIGNIFICANCE: Research priorities in Chad and Egypt should focus on quantifying population size and pressures exerted on habitats. The present study increased in by 35% the number of known crocodile localities in Mauritania. Gueltas are crucial for the persistence of mountain populations. Oscillations in water availability throughout the year and the small dimensions of gueltas affect biological traits, including activity and body size. Studies are needed to understand adaptation traits of desert populations. Molecular analyses are needed to quantify genetic variability, population sub-structuring and effective population size, and detect the occurrence of gene flow. Monitoring is needed to detect demographical and genetical trends in completely isolated populations. Crocodiles are apparently vulnerable during dispersal events. Awareness campaigns focusing on

  16. Stable oxygen isotopic composition of corals from the Gulf of Guinea as indicators of periods of extreme precipitation conditions in the sub-Sahara

    Science.gov (United States)

    Swart, Peter K.; White, Kathy S.; Enfield, David; Dodge, Richard E.; Milne, Peter

    1998-11-01

    Stable oxygen isotopic analyses of scleractinian coral skeletons from the Gulf of Guinea in the eastern Atlantic reveal that the corals from this region can be used to identify periods of severe drought and above average precipitation in sub-Sahara Africa. Data presented in this paper show an inverse correlation between precipitation in the Sahel and the δ18O values of a coral skeletons of the species Siderastrea spp. collected from the island of Principe in the Gulf of Guinea. This is opposite to the correlation expected, as previous work has suggested that higher sea surface temperatures occur in the Gulf of Guinea during periods of low rainfall in the Sahel. Such an association would lead to a positive correlation between Sahel precipitation and skeletal δ18O. The explanation for the observed inverse correlation is that the salinity of the Gulf of Guinea is strongly influenced by the outflow from the Niger and Congo rivers. These periods of high freshwater input also correlate with periods of higher rainfall in the sub-Sahara and therefore affect the δ18O values of the coral skeleton. The correlation between δ18O values of the coral skeleton and temperature in the northern subtropical Atlantic Ocean (r = -0.34), the magnitude of the dipole (r = -0.45), and the latitudinal position of the intertropical convergence zone (r = -0.37) illustrate that the δ18O values in the coral skeleton reflect climate dynamics of the region that affect the precipitation patterns in sub-Sahara Africa.

  17. Factors influencing IUCN threat levels to orchids across Europe on the basis of national red lists.

    Science.gov (United States)

    Kull, Tiiu; Selgis, Ulvi; Peciña, Miguel Villoslada; Metsare, Mirjam; Ilves, Aigi; Tali, Kadri; Sepp, Kalev; Kull, Kalevi; Shefferson, Richard P

    2016-09-01

    The red list has become a ubiquitous tool in the conservation of species. We analyzed contemporary trends in the threat levels of European orchids, in total 166 species characterized in 27 national red lists, in relation to their reproductive biology and growth form, distribution area, and land cover where they occur. We found that species in central Europe are more threatened than those in the northern, southern, or Atlantic parts of Europe, while species were least threatened in southern Europe. Nectarless and tuberous species are significantly more threatened than nectariferous and rhizomatous taxa. Land cover (ratios of artificial land cover, area of pastures and grasslands, forests and inland wetlands) also significantly impacted the threat level. A bigger share of artificial land cover increases threat, and a bigger share of pasture and grassland lowers it. Unexpectedly, a bigger share of inland wetland area in a country increased threat level, which we believe may be due to the threatened nature of wetlands themselves relative to other natural land cover types. Finally, species occurring in multiple countries are on average less threatened. We believe that large-scale analysis of current IUCN national red lists as based on their specific categories and criteria may particularly inform the development of coordinated regional or larger-scale management strategies. In this case, we advocate for a coordinated EU protection and restoration strategy particularly aimed at central European orchids and those occurring in wetland area.

  18. El Sahara Occidental : alimentación y cocina tradicional : aspectos culturales, lingüísticos y etnobotánicos

    OpenAIRE

    Baya E., Moulay-Lahssan

    2014-01-01

    Esta tesis aborda diversos aspectos relacionados con la alimentación y la cocina tradicional de las sociedades beduinas o seminómadas del Sahara Occidental. Dichos aspectos se enmarcan dentro de su contexto cultural y sociológico; de modo que, además de los temas alimentarios, se abordan aspectos culturales, lingüísticos y etnobotánicos. La investigación está basada fundamentalmente en fuentes orales, que, a su vez, son contrastadas y complementadas con la documentación que suministran algun...

  19. Cyber Conflicts as a New Global Threat

    Directory of Open Access Journals (Sweden)

    Alexander Kosenkov

    2016-09-01

    Full Text Available In this paper, an attempt is made to analyze the potential threats and consequences of cyber conflicts and, in particular, the risks of a global cyber conflict. The material is based on a comprehensive analysis of the nature of cyber conflict and its elements from both technical and societal points of view. The approach used in the paper considers the societal component as an essential part of cyber conflicts, allowing basics of cyber conflicts often disregarded by researchers and the public to be highlighted. Finally, the conclusion offers an opportunity to consider cyber conflict as the most advanced form of modern warfare, which imposes the most serious threat and whose effect could be comparable to weapons of mass destruction.

  20. Securing Infrastructure from High Explosive Threats

    Energy Technology Data Exchange (ETDEWEB)

    Glascoe, L; Noble, C; Reynolds, J; Kuhl, A; Morris, J

    2009-03-20

    Lawrence Livermore National Laboratory (LLNL) is working with the Department of Homeland Security's Science and Technology Directorate, the Transportation Security Administration, and several infrastructure partners to characterize and help mitigate principal structural vulnerabilities to explosive threats. Given the importance of infrastructure to the nation's security and economy, there is a clear need for applied research and analyses (1) to improve understanding of the vulnerabilities of these systems to explosive threats and (2) to provide decision makers with time-critical technical assistance concerning countermeasure and mitigation options. Fully-coupled high performance calculations of structural response to ideal and non-ideal explosives help bound and quantify specific critical vulnerabilities, and help identify possible corrective schemes. Experimental validation of modeling approaches and methodologies builds confidence in the prediction, while advanced stochastic techniques allow for optimal use of scarce computational resources to efficiently provide infrastructure owners and decision makers with timely analyses.

  1. Detecting underwater improvised explosive threats (DUIET)

    Science.gov (United States)

    Feeley, Terry

    2010-04-01

    Improvised Explosive Devices (IEDs) have presented a major threat in the wars in Afghanistan and Iraq. These devices are powerful homemade land mines that can be small and easily hidden near roadsides. They are then remotely detonated when Coalition Forces pass by either singly or in convoys. Their rapid detection, classification and destruction is key to the safety of troops in the area. These land based bombs will have an analogue in the underwater theater especially in ports, lakes, rivers and streams. These devices may be used against Americans on American soil as an element of the global war on terrorism (GWOT) Rapid detection and classification of underwater improvised explosive devices (UIED) is critical to protecting innocent lives and maintaining the day to day flow of commerce. This paper will discuss a strategy and tool set to deal with this potential threat.

  2. Threat Modeling-Oriented Attack Path Evaluating Algorithm

    Institute of Scientific and Technical Information of China (English)

    LI Xiaohong; LIU Ran; FENG Zhiyong; HE Ke

    2009-01-01

    In order to evaluate all attack paths in a threat tree,based on threat modeling theory,a weight distribution algorithm of the root node in a threat tree is designed,which computes threat coefficients of leaf nodes in two ways including threat occurring possibility and the degree of damage.Besides,an algorithm of searching attack path was also obtained in accordence with its definition.Finally,an attack path evaluation system was implemented which can output the threat coefficients of the leaf nodes in a target threat tree,the weight distribution information,and the attack paths.An example threat tree is given to verify the effectiveness of the algorithms.

  3. Common Viruses a Deadly Threat At Nursing Homes

    Science.gov (United States)

    ... 163048.html Common Viruses a Deadly Threat at Nursing Homes RSV and human metapneumovirus need to be ... News) -- Common viruses pose a serious threat in nursing homes, often sabotaging standard infection control measures, a ...

  4. 41 CFR 60-741.22 - Direct threat defense.

    Science.gov (United States)

    2010-07-01

    ... INDIVIDUALS WITH DISABILITIES Discrimination Prohibited § 60-741.22 Direct threat defense. The contractor may... individual or others in the workplace. (See § 60-741.2(y) defining direct threat.)...

  5. Introduction to Administrative Programs that Mitigate the Insider Threat

    Energy Technology Data Exchange (ETDEWEB)

    Gerke, Gretchen K.; Rogers, Erin; Landers, John; DeCastro, Kara

    2012-09-01

    This presentation begins with the reality of the insider threat, then elaborates on these tools to mitigate the insider threat: Human Reliability Program (HRP); Nuclear Security Culture (NSC) Program; Employee Assistance Program (EAP).

  6. American Jihadist Terrorism: Combating a Complex Threat

    Science.gov (United States)

    2010-12-07

    context of terrorism, the Arabic word jihad is derived from a verb that means “to struggle, strive, or exert oneself.” It appears in the Quran in the...4. American Jihadist Terrorism: Combating a Complex Threat Congressional Research Service 68 looked “ beautiful .”331 They later drove the van to...purchased chemicals at beauty supply stores in Denver. Investigators suggest that Zazi used the same hotel suite twice to try and produce bomb-making

  7. Nonproliferation, Nuclear Security, and the Insider Threat

    Energy Technology Data Exchange (ETDEWEB)

    Balatsky, Galya I. [Los Alamos National Laboratory; Duggan, Ruth [SNL

    2012-07-12

    Insider threat concept is evolving and getting more attention: (1) Domestically, internationally and in foreign countries, (2) At the government, academia, and industry levels, and (3) Public awareness and concerns are also growing. Negligence can be an insider's action. Technology advancements provide more opportunities, new tools for the insider. Our understanding of the insider is shaped by our cultural, social and ethnic perceptions and traditions. They also can limit our recognition of the issues and response actions.

  8. Handsets Malware Threats and Facing Techniques

    CERN Document Server

    Elfattah, Marwa M A; Sarhan, Ebada

    2012-01-01

    Nowadays, mobile handsets combine the functionality of mobile phones and PDAs. Unfortunately, mobile handsets development process has been driven by market demand, focusing on new features and neglecting security. So, it is imperative to study the existing challenges that facing the mobile handsets threat containment process, and the different techniques and methodologies that used to face those challenges and contain the mobile handsets malwares. This paper also presents a new approach to group the different malware containment systems according to their typologies.

  9. The Divisive Threat of Immigration in Europe

    Science.gov (United States)

    2012-12-01

    Europe , immigrant children consistently underperformed in reading. This disparity suggests that immigrant children will have lower literacy rates, less...OF IMMIGRATION IN EUROPE by Andrew J. Sheehan Lars W. Lilleby December 2012 Thesis Advisor: Gordon McCormick Second Reader: Anna...COVERED Master’s Thesis 4. TITLE AND SUBTITLE The Divisive Threat of Immigration in Europe 5. FUNDING NUMBERS 6. AUTHOR(S) Lars W. Lilleby

  10. Community Changes Address Common Health Threat

    Centers for Disease Control (CDC) Podcasts

    2013-09-30

    This podcast helps residents living in multiunit housing, like apartments and condos, understand the threat of secondhand smoke. It also helps residents understand what steps they can take to breathe a little easier if involuntarily exposed to secondhand smoke.  Created: 9/30/2013 by Division of Community Health, National Center for Chronic Disease Prevention and Health Promotion.   Date Released: 9/30/2013.

  11. Deployable centralizers

    Energy Technology Data Exchange (ETDEWEB)

    Grubelich, Mark C.; Su, Jiann-Cherng; Knudsen, Steven D.

    2017-02-28

    A centralizer assembly is disclosed that allows for the assembly to be deployed in-situ. The centralizer assembly includes flexible members that can be extended into the well bore in situ by the initiation of a gas generating device. The centralizer assembly can support a large load carrying capability compared to a traditional bow spring with little or no installation drag. Additionally, larger displacements can be produced to centralize an extremely deviated casing.

  12. Asymmetric threat data mining and knowledge discovery

    Science.gov (United States)

    Gilmore, John F.; Pagels, Michael A.; Palk, Justin

    2001-03-01

    Asymmetric threats differ from the conventional force-on- force military encounters that the Defense Department has historically been trained to engage. Terrorism by its nature is now an operational activity that is neither easily detected or countered as its very existence depends on small covert attacks exploiting the element of surprise. But terrorism does have defined forms, motivations, tactics and organizational structure. Exploiting a terrorism taxonomy provides the opportunity to discover and assess knowledge of terrorist operations. This paper describes the Asymmetric Threat Terrorist Assessment, Countering, and Knowledge (ATTACK) system. ATTACK has been developed to (a) data mine open source intelligence (OSINT) information from web-based newspaper sources, video news web casts, and actual terrorist web sites, (b) evaluate this information against a terrorism taxonomy, (c) exploit country/region specific social, economic, political, and religious knowledge, and (d) discover and predict potential terrorist activities and association links. Details of the asymmetric threat structure and the ATTACK system architecture are presented with results of an actual terrorist data mining and knowledge discovery test case shown.

  13. Bot armies as threats to network security

    Science.gov (United States)

    Banks, Sheila B.; Stytz, Martin R.

    2007-04-01

    "Botnets", or "bot armies", are large groups of remotely controlled malicious software. Bot armies pose one of the most serious security threats to all networks. Botnets, remotely controlled and operated by botmasters or botherders, can launch massive denial of service attacks, multiple penetration attacks, or any other malicious network activity on a massive scale. While bot army activity has, in the past, been limited to fraud, blackmail, and other forms of criminal activity, their potential for causing large-scale damage to the entire internet; for launching large-scale, coordinated attacks on government computers and networks; and for large-scale, coordinated data gathering from thousands of users and computers on any network has been underestimated. This paper will not discuss how to build bots but the threats they pose. In a "botnet" or "bot army", computers can be used to spread spam, launch denial-of-service attacks against Web sites, conduct fraudulent activities, and prevent authorized network traffic from traversing the network. In this paper we discuss botnets and the technologies that underlie this threat to network and computer security. The first section motivates the need for improved protection against botnets, their technologies, and for further research about botnets. The second contains background information about bot armies and their key underlying technologies. The third section presents a discussion of the types of attacks that botnets can conduct and potential defenses against them. The fourth section contains a summary and suggestions for future research and development.

  14. Mere effort and stereotype threat performance effects.

    Science.gov (United States)

    Jamieson, Jeremy P; Harkins, Stephen G

    2007-10-01

    Although the fact that stereotype threat impacts performance is well established, the underlying process(es) is(are) not clear. Recently, T. Schmader and M. Johns (2003) argued for a working memory interference account, which proposes that performance suffers because cognitive resources are expended on processing information associated with negative stereotypes. The antisaccade task provides a vehicle to test this account because optimal performance requires working memory resources to inhibit the tendency to look at an irrelevant, peripheral cue (the prepotent response) and to generate volitional saccades to the target. If stereotype threat occupies working memory resources, then the ability to inhibit the prepotent response and to launch volitional saccades will be impaired, and performance will suffer. In contrast, S. Harkins's (2006) mere effort account argues that stereotype threat participants are motivated to perform well, which potentiates the prepotent response, but also leads to efforts to counter this tendency if participants recognize that the response is incorrect, know the correct response, and have the opportunity to make it. Results from 4 experiments support the mere effort but not the working memory interference account.

  15. Cyber threat model for tactical radio networks

    Science.gov (United States)

    Kurdziel, Michael T.

    2014-05-01

    The shift to a full information-centric paradigm in the battlefield has allowed ConOps to be developed that are only possible using modern network communications systems. Securing these Tactical Networks without impacting their capabilities has been a challenge. Tactical networks with fixed infrastructure have similar vulnerabilities to their commercial counterparts (although they need to be secure against adversaries with greater capabilities, resources and motivation). However, networks with mobile infrastructure components and Mobile Ad hoc Networks (MANets) have additional unique vulnerabilities that must be considered. It is useful to examine Tactical Network based ConOps and use them to construct a threat model and baseline cyber security requirements for Tactical Networks with fixed infrastructure, mobile infrastructure and/or ad hoc modes of operation. This paper will present an introduction to threat model assessment. A definition and detailed discussion of a Tactical Network threat model is also presented. Finally, the model is used to derive baseline requirements that can be used to design or evaluate a cyber security solution that can be scaled and adapted to the needs of specific deployments.

  16. Culture, threat, and mental illness stigma: identifying culture-specific threat among Chinese-American groups.

    Science.gov (United States)

    Yang, Lawrence H; Purdie-Vaughns, Valerie; Kotabe, Hiroki; Link, Bruce G; Saw, Anne; Wong, Gloria; Phelan, Jo C

    2013-07-01

    We incorporate anthropological insights into a stigma framework to elucidate the role of culture in threat perception and stigma among Chinese groups. Prior work suggests that genetic contamination that jeopardizes the extension of one's family lineage may comprise a culture-specific threat among Chinese groups. In Study 1, a national survey conducted from 2002 to 2003 assessed cultural differences in mental illness stigma and perceptions of threat in 56 Chinese-Americans and 589 European-Americans. Study 2 sought to empirically test this culture-specific threat of genetic contamination to lineage via a memory paradigm. Conducted from June to August 2010, 48 Chinese-American and 37 European-American university students in New York City read vignettes containing content referring to lineage or non-lineage concerns. Half the participants in each ethnic group were assigned to a condition in which the illness was likely to be inherited (genetic condition) and the rest read that the illness was unlikely to be inherited (non-genetic condition). Findings from Study 1 and 2 were convergent. In Study 1, culture-specific threat to lineage predicted cultural variation in stigma independently and after accounting for other forms of threat. In Study 2, Chinese-Americans in the genetic condition were more likely to accurately recall and recognize lineage content than the Chinese-Americans in the non-genetic condition, but that memorial pattern was not found for non-lineage content. The identification of this culture-specific threat among Chinese groups has direct implications for culturally-tailored anti-stigma interventions. Further, this framework might be implemented across other conditions and cultural groups to reduce stigma across cultures.

  17. 电测深法在撒哈拉沙漠地区找水应用%The Application of Electrical Sounding to Water Exploration in Sahara

    Institute of Scientific and Technical Information of China (English)

    唐英杰

    2014-01-01

    Because of the arid climate and water scarcity, few study on geology and hydrogeology of Sahara has been taken.The lack of study in this field has made water exploration in Sahara harder .On the basis of previous research data , the study is taken step by step to explore the unknown research field.With the help of electrical sounding, aquifers'location are identified and physical properties of them are concluded.The study is scientific and its results can be a reference for further work on hydrogeology .%撒哈拉沙漠地区气候干燥,水资源缺乏,相应的地质、水文地质工作研究程度低,为水源地勘探工作带来很大困难。结合实例,采用电测深法,遵循从已知到未知原则,经过点、线、面逐步开展工作,总结含水层物性特征,划定主要含水区域,为水文工作的开展提供重要的基础资料。

  18. COMPARATIVE ANALYSIS POLICY OF GERMANY, BRITAIN AND FRANCE IN CENTRAL ASIA

    OpenAIRE

    S. M. Yun

    2011-01-01

    Abstract: Germany, Great Britain and France stated their interests in Central Asia immediately after the disintegration of USSR. In 1994 and 1995 the policies of the leading European countries towards Central Asia stressed the restraining of Russia’s neo-imperial ambitions in the post-soviet space and the support of economic independence of Central Asian states. As of late 1990s the regional policies prioritized fighting the drug threat and after September 11, 2001 — the terrorism threat. The...

  19. Fall 2014 SEI Research Review Insider Threat Mitigation LINE Project

    Science.gov (United States)

    2014-10-01

    Fall 2014 SEI Research Review Moore, 28-30 October 2014 © 2014 Carnegie Mellon University Contact Information Slide Format Presenter / Point of...published • Threat models published in book: CERT Guide to Insider Threats (2012) • Pattern-Based Design of Insider Threat Programs: Forthcoming 12

  20. An Examination of Stereotype Threat Effects on Girls' Mathematics Performance

    Science.gov (United States)

    Ganley, Colleen M.; Mingle, Leigh A.; Ryan, Allison M.; Ryan, Katherine; Vasilyeva, Marina; Perry, Michelle

    2013-01-01

    Stereotype threat has been proposed as 1 potential explanation for the gender difference in standardized mathematics test performance among high-performing students. At present, it is not entirely clear how susceptibility to stereotype threat develops, as empirical evidence for stereotype threat effects across the school years is inconsistent. In…

  1. Death Threat and Death Concerns in the College Student.

    Science.gov (United States)

    Tobacyk, Jerome; Eckstein, Daniel

    1980-01-01

    Thanatology students reported significantly lesser death threat and significantly greater death concerns. Trait anxiety was found to be a significant predictor of change in death threat in the Thanatology Group, with lesser anxiety associated with greater decline in death threat. (Author)

  2. Traits, States, and Attentional Gates: Temperament and Threat Relevance as Predictors of Attentional Bias to Social Threat

    OpenAIRE

    2009-01-01

    This study investigated the influence of situational and dispositional factors on attentional biases toward social threat, and the impact of these attentional biases on distress in a sample of adolescents. Results suggest greater biases for personally-relevant threat cues, as individuals reporting high social stress were vigilant to subliminal social threat cues, but not physical threat cues, and those reporting low social stress showed no attentional biases. Individual differences in fearful...

  3. Rift Valley fever: Real or perceived threat for Zambia?

    Directory of Open Access Journals (Sweden)

    George Dautu

    2012-06-01

    Full Text Available Rift Valley fever (RVF in Zambia was first reported in 1974 during an epizootic of cattle and sheep that occurred in parts of Central, Southern and Copperbelt Provinces. In 1990, the disease was documented in nine districts of the provinces of Zambia. In the last two decades, there have been no reports of RVF. This long period without reported clinical disease raises questions as to whether RVF is a current or just a perceived threat. To address this question, World Organisation for Animal Health (OIE disease occurrence data on RVF for the period 2005−2010 in the Southern Africa Development Community (SADC was analysed. From the analysis, it was evident that most countries that share a common border with Zambia had reported at least one occurrence of the disease during the period under review. Due to the absence of natural physical barriers between Zambia and most of her neighbours, informal livestock trade and movements is a ubiquitous reality. Analysis of the rainfall patterns also showed that Zambia received rains sufficient to support a mosquito population large enough for high risk of RVF transmission. The evidence of disease occurrence in nearby countries coupled with animal movement, and environmental risk suggests that RVF is a serious threat to Zambia. In conclusion, the current occurrence of RVF in Zambia is unclear, but there are sufficient indications that the magnitude of the circulating infection is such that capacity building in disease surveillance and courses on recognition of the disease for field staff is recommended. Given the zoonotic potential of RVF, these measures are also a prerequisite for accurate assessment of the disease burden in humans.

  4. Environmental changes in the Central Sahara during the Holocene - The Mid-Holocene transition from freshwater lake into sebkha in the Segedim depression, NE Niger

    Science.gov (United States)

    Baumhauer, Roland; Schulz, Erhard; Pomel, Simon

    The change from a fresh water lake to a sebkha during the middle Holocene was investigated in the Segedim depression/North-eastern Niger using continuous thin sections for micropetrography, palynology and for diatoms. This record is clearly divided into several units showing sequences of laminated anoxic to oxic clays, the stage of a sebkha with an inflow of loess, fine broken quartz grains and salts which are covered by dune sands made of rounded and clay covered quartz. The mineral assemblages of the three principal units are defined by the illite/kaolinitecalcite The diatom assemblages equally show the passage from fresh to saline water. The pollen spectra indicate the change from the Saharan savannah to desert vegetation.

  5. When threats foreign turn domestic : Two ways for distant realistic intergroup threats to carry over into local intolerance

    NARCIS (Netherlands)

    Bouman, Thijs; van Zomeren, Martijn; Otten, Sabine

    2015-01-01

    In times of economic downturn, perceived realistic intergroup threats (e.g., labour competition) often dominate political and media discourse. Although local outgroups (e.g., local immigrants) can be experienced as sources of realistic threats, we propose that such threats can also be perceived to b

  6. Sahara and Sahel vulnerability to climate changes, lessons from the past - Focus on the Ounianga lake region (NE Chad)

    Science.gov (United States)

    Grenier, Christophe; Zheng, Weipeng; Lezine, Anne-Marie; Braconnot, Pascale; Krinner, Gerhard; Harel, Marie-Alice; Anglade, Juliette; Paillou, Philippe

    2010-05-01

    Reconstructions from sedimentary records and climate modelling results show an overall drying in the African Sahara and Sahel during the Holocene. Was this change abrupt or gradual, and amplified or not through vegetation change and feedbacks to the atmosphere is still the subject of debate. For instance, while [deMenocal et al. 2000] show from oceanic sediments off the Mauritanian coast, that the end of the African Humid Period (AHP), recorded 5500 years ago, was abrupt. [Kroepelin et al., 2008] studied recently sediments from lake Yoa (Ounianga region, NE Chad) and derived a gradual climate change. The present paper focusses on the Ounianga lake region (NE Chad) where the Kropelin et al. study was carried on. We investigate hydrological reconstructions based on climate scenarios and modelling of water dynamics of the catchment area of the lakes. Under modern conditions, Ounianga lakes are maintained in a hyper arid environment due to groundwater inputs from the Nubian Sandstone Aquifer System (NSAS), a very large aquifer covering parts of Chad, Libya, Egypt and Sudan. Moreover, these lakes are situated within 200 km of the Tibesti Mountains ranging over 3000 meters where rainfall is larger than in the plains. So the issue arises as to what extent distant water inputs from the Tibesti and local groundwater recharge could have maintained high lake levels during the climatic transition phase and/or could explain some features analysed from the sediments regarding the abruptness of the salinisation of lake Yoa roughly by 3900 BP. The topography of the region is analyzed from SRTM data to obtain paleo river networks and compared with satellite radar pictures (PALSAR) to identify key features in the Yoa catchement area [refer to Grenier et al. 2009]. A hydrological model is constructed including the river network and depressions interpreted as lakes and modeled dynamically as reservoirs. The groundwater input from the aquifer is modeled within the Cast3m finite element

  7. Private Higher Education in a Cold War World: Central America

    Science.gov (United States)

    Harrington, James J.

    2009-01-01

    In Central America the Cold War support of the elites by the United States was designed to ward off the communist threat. At the same time social and economic demands by the working and middle classes created revolutionary movements in the face of rigid and violent responses by Central American governments. Issues of social justice pervaded the…

  8. ‘Everybody knows’, but the rest of the world: the case of a caterpillar-borne reproductive loss syndrome in dromedary camels observed by Sahrawi pastoralists of Western Sahara

    NARCIS (Netherlands)

    Volpato, G.; Nardo, Di A.; Rossi, D.; Lamin Saleh, S.; Broglia, A.

    2013-01-01

    Background The traditional knowledge of local communities throughout the world is a valuable source of novel ideas and information to science. In this study, the ethnoveterinary knowledge of Sahrawi pastoralists of Western Sahara has been used in order to put forward a scientific hypothesis regardin

  9. SURVEY OF BIBLIOGRAPHIES AND REFERENCE WORKS ON ASIA, AFRICA, LATIN AMERICA, RUSSIA, AND EAST EUROPE--AND COMPILATION OF BIBLIOGRAPHIES ON EAST ASIA, SOUTH ASIA AND AFRICA SOUTH OF THE SAHARA FOR UNDERGRADUATE LIBRARIES. INTERIM REPORT, PHASE ONE.

    Science.gov (United States)

    MOREHOUSE, WARD

    THE PURPOSE OF THE PROJECT IS TO ASSIST UNDERGRADUATE LIBRARIES IN STRENGTHENING THEIR RESOURCES ON AREAS OUTSIDE THE PERIMETER OF WESTERN CIVILIZATION USUALLY GIVEN LITTLE ATTENTION BY AMERICAN COLLEGES, WITH SPECIAL EMPHASIS ON EAST AND SOUTH ASIA AND AFRICA SOUTH OF THE SAHARA. UNDER THE PROJECT'S FIRST PHASE, A PANEL OF LIBRARY ADVISERS WAS…

  10. Threat model framework and methodology for personal networks (PNs)

    DEFF Research Database (Denmark)

    Prasad, Neeli R.

    2007-01-01

    To be able to build a secure network, it is essential to model the threats to the network. A methodology for building a threat model has been proposed in the paper. Several existing threat models and methodologies will be compared to the proposed methodology. The aim of the proposed methodology...... is to give a structured, convenient approach for building threat models. A framework for the threat model is presented with a list of requirements for methodology. The methodology will be applied to build a threat model for Personal Networks. Practical tools like UML sequence diagrams and attack trees have...... been used. Also risk assessment methods will be discussed. Threat profiles and vulnerability profiles have been presented....

  11. Protection without detection: a threat mitigation technique

    Science.gov (United States)

    White, Joshua; McCoy, Joseph R.; Ratazzi, Paul

    2012-05-01

    Networking systems and individual applications have traditionally been defended using signature-based tools that protect the perimeter, many times to the detriment of service, performance, and information flow. These tools require knowledge of both the system on which they run and the attack they are preventing. As such, by their very definition, they only account for what is known to be malicious and ignore the unknown. The unknown, or zero day threat, can occur when defenses have yet to be immunized via a signature or other identifier of the threat. In environments where execution of the mission is paramount, the networks and applications must perform their function of information delivery without endangering the enterprise or losing the salient information, even when facing zero day threats. In this paper we, describe a new defensive strategy that provides a means to more deliberately balance the oft mutually exclusive aspects of protection and availability. We call this new strategy Protection without Detection, since it focuses on network protection without sacrificing information availability. The current instantiation analyzes the data stream in real time as it passes through an in-line device. Critical files are recognized, and mission-specific trusted templates are applied as they are forwarded to their destination. The end result is a system which eliminates the opportunity for propagation of malicious or unnecessary payloads via the various containers that are inherent in the definition of standard file types. In some cases, this method sacrifices features or functionality that is typically inherent in these files. However, with the flexibility of the template approach, inclusion or exclusion of these features becomes a deliberate choice of the mission owners, based on their needs and amount of acceptable risk. The paper concludes with a discussion of future extensions and applications.

  12. Assessing the global threat from Zika virus.

    Science.gov (United States)

    Lessler, Justin; Chaisson, Lelia H; Kucirka, Lauren M; Bi, Qifang; Grantz, Kyra; Salje, Henrik; Carcelen, Andrea C; Ott, Cassandra T; Sheffield, Jeanne S; Ferguson, Neil M; Cummings, Derek A T; Metcalf, C Jessica E; Rodriguez-Barraquer, Isabel

    2016-08-12

    First discovered in 1947, Zika virus (ZIKV) infection remained a little-known tropical disease until 2015, when its apparent association with a considerable increase in the incidence of microcephaly in Brazil raised alarms worldwide. There is limited information on the key factors that determine the extent of the global threat from ZIKV infection and resulting complications. Here, we review what is known about the epidemiology, natural history, and public health effects of ZIKV infection, the empirical basis for this knowledge, and the critical knowledge gaps that need to be filled.

  13. Cybersecurity Public Sector Threats and Responses

    CERN Document Server

    Andreasson, Kim J

    2011-01-01

    The Internet has given rise to new opportunities for the public sector to improve efficiency and better serve constituents in the form of e-government. But with a rapidly growing user base globally and an increasing reliance on the Internet, digital tools are also exposing the public sector to new risks. An accessible primer, Cybersecurity: Public Sector Threats and Responses focuses on the convergence of globalization, connectivity, and the migration of public sector functions online. It identifies the challenges you need to be aware of and examines emerging trends and strategies from around

  14. Rethinking climate change as a security threat

    Energy Technology Data Exchange (ETDEWEB)

    Schoch, Corinne

    2011-10-15

    Once upon a time climate change was a strictly environment and development issue. Today it has become a matter of national and international security. Efforts to link climate change with violent conflict may not be based on solid evidence, but they have certainly captured the attention of governments. They have played a vital role in raising the much-needed awareness of climate change as an issue that deserves global action. But at what cost? Focusing on climate change as a security threat alone risks devolving humanitarian responsibilities to the military, ignoring key challenges and losing sight of those climate-vulnerable communities that stand most in need of protection.

  15. Swimming in the Sahara

    Institute of Scientific and Technical Information of China (English)

    Alex; Stone; 于文

    2007-01-01

    非洲的撒哈拉大沙漠总会使人想起干旱、贫瘠和荒凉的画面。然而,是不是盘古开天地以来,它就是一望无际、了无人烟的沙漠呢?历史上的撒哈拉沙漠究竟是什么样子?德国科隆大学的地质考古学家Stefan Kropclin通过对东撒哈拉长达30年的挖掘,以及对其出土的文物,例如动物骨骼、山洞艺术品等研究,对以上问题给出了明确的答案。他认为,过去的撒哈拉大沙漠曾是一个生机勃勃的绿色伊甸园,将来它必将重现昔日草木葱茏的景像。

  16. Prefrontal control of attention to threat.

    Science.gov (United States)

    Peers, Polly V; Simons, Jon S; Lawrence, Andrew D

    2013-01-01

    Attentional control refers to the regulatory processes that ensure that our actions are in accordance with our goals. Dual-system accounts view temperament as consisting of both individual variation in emotionality (e.g., trait anxiety) and variation in regulatory attentional mechanisms that act to modulate emotionality. Increasing evidence links trait variation in attentional control to clinical mood and anxiety disorder symptoms, independent of trait emotionality. Attentional biases to threat have been robustly linked to mood and anxiety disorders. However, the role of variation in attentional control in influencing such biases, and the neural underpinnings of trait variation in attentional control, are unknown. Here, we show that individual differences in trait attentional control, even when accounting for trait and state anxiety, are related to the magnitude of an attentional blink (AB) following threat-related targets. Moreover, we demonstrate that activity in dorso-lateral prefrontal cortex (DLPFC), is observed specifically in relation to control of attention over threatening stimuli, in line with neural theories of attentional control, such as guided activation theory. These results have key implications for neurocognitive theories of attentional bias and emotional resilience.

  17. Prefrontal control of attention to threat

    Directory of Open Access Journals (Sweden)

    Polly V Peers

    2013-02-01

    Full Text Available Attentional control refers to the regulatory processes that ensure that our actions are in accordance with our goals. Dual-system accounts view temperament as consisting of both individual variation in emotionality (e.g. trait anxiety and variation in regulatory attentional mechanisms that act to modulate emotionality. Increasing evidence links trait variation in attentional control to clinical mood and anxiety disorder symptoms, independent of trait emotionality. Attentional biases to threat have been robustly linked to mood and anxiety disorders. However, the role of variation in attentional control in influencing such biases, and the neural underpinnings of trait variation in attentional control, are unknown. Here, we show, that individual differences in trait attentional control, even when accounting for trait and state anxiety, are related to the magnitude of an attentional blink following threat-related targets. Moreover, we demonstrate that activity in dorsolateral prefrontal cortex, is observed specifically in relation to control of attention over threatening stimuli, in line with neural theories of attentional control, such as guided activation theory. These results have key implications for neurocognitive theories of attentional bias and emotional resilience.

  18. Nuclear Smuggling and Threats to Lithuanian Security

    Directory of Open Access Journals (Sweden)

    Murauskaitė Eglė

    2016-12-01

    Full Text Available The article explores threats related to illicit trafficking of radioactive materials and dual-use goods applicable in state level nuclear programs, actualizing the global trends for the Baltic region. The article points to Eastern Europe’s changing risk profile in this respect, as increasing penetration of Russian criminal groups inside Ukraine and the destabilized situations in neighboring countries create an environment where the risk of nuclear smuggling is on the rise. Criminal entities can be seen forming new bonds, with trafficking routes intersecting and zones of influence shifting - consequently, an unusual level of criminal involvement in nuclear smuggling is observed, alongside a geographic shift of smuggling patterns. In addition, states seeking materials and technologies for their military programs have taken a notable interest in this region as a way of circumventing international transit regulations. The article looks at the likely implications of these new nuclear smuggling trends for the security of the Baltic states. It suggests that Lithuania may soon be facing a relatively new threat, and one that it is ill-prepared to counter. The article discusses the risk factors and indicators to watch before that risk becomes reality, and offers ways for Lithuania to contribute to addressing these increasingly acute problems on a regional level.

  19. Ongoing Threats to Emerging Financial Entities

    Directory of Open Access Journals (Sweden)

    Bryce Alexander LYNCH

    2016-06-01

    Full Text Available In the twenty-first century the pace of technological advancement shows no signs of stopping. Old technologies are being discarded as obsolete or are transformed in ways that nobody could have foreseen even a half-decade ago. Along with these radical changes come vulnerabilities and threats to infrastructure, including informational and financial which must be considered and protected. This is not to say that basic security measures must continue to be neglected in favor of rapid development and deployment to provide a Minimum Viable Product to customers; basic security protocols become all the more important under these circumstances. Improving faster are attacks against the new infrastructure; technique and technology tend to change along generally accepted sets of rules while attackers follow no rules or guidelines. This fundamental asymmetry leaves defenders at a distinct advantage in several ways, including ethical concerns (“There are some lines we will not cross” versus “By any means necessary”, monetary considerations (“Return on investment” versus “The resources aren’t ours to begin with, so who cares” and pragmatism (“We exist to make money to improve shareholder value” versus “Because it’s there”. That said, measurable, repeatable, and effective countermeasures exist which can be deployed on an enterprise-wide basis to help level the playing field by deterring attackers. This paper will discuss these threats along with active and passive countermeasures for same.

  20. Unattended sensors for nuclear threat detection

    Energy Technology Data Exchange (ETDEWEB)

    Runkle, Robert C.; Myjak, Mitchell J.; Batdorf, Michael T.; Bowler, Ryan S.; Kiff, Scott D.; Morris, Scott J.; Mullen, Crystal A.; Rohrer, John S.; Todd, Lindsay C.

    2008-06-30

    This paper discusses the ongoing development of a compact, unattended, and low-power radiation detection system designed for deployment to the front lines of nuclear proliferation. Current countermeasure deployments aim to detect nuclear threats by screening cargo containers abroad or at ports of entry, but the defensive nature of these systems means that they face the immense challenge of detecting intentionally-concealed materials. A complementary strategy places countermeasures closer to the source of nuclear proliferation, but deployments to these regions often must operate autonomously and in the absence of infrastructure. This application motivates our development of a low-power system capable of detecting gamma-ray and neutron emissions while operating autonomously for extended periods of time. Many challenges are present when developing radiation-detection systems for this application, and this paper describes work focused on two of them: the development of compact, low-power electronics for gamma-ray-spectrometer and 3He- tube signal processing, and analysis algorithms capable of distinguishing threats from benign sources in mid-resolution gamma-ray spectrometers. We discuss our development efforts on these fronts and present results based on implementation in a proof-of-principle system comprised of two 5 cm x 10 cm x 41 cm NaI(Tl) crystals and eight 40-cm 3He tubes.

  1. Overview of the Distributed Mission Training Integrated Threat Environment project

    Science.gov (United States)

    Stytz, Martin R.; Banks, Sheila B.; Santos, Eugene, Jr.

    1998-08-01

    The Joint Synthetic Battlespace (JSB) envisioned within the Department of Defense modeling and simulation master plan requires a distributed virtual environment (DVE) wide consistent threat environment to achieve a useful mission rehearsal, training, test and evaluation capability. To achieve this objective, all threats in the DVE must appear at compatible levels of fidelity to all the entities operating in the DVE and they must interact with human- operated and computer-controlled entities in a realistic fashion. Achieving this goal is not currently possible for two reasons. First, each primary aircraft simulator training system developer has created their own threat system and made their own modeling decisions to support a specific user for a select few predetermined conditions. This traditional threat simulation approach is expensive and leads to ongoing difficulties in maintaining threat currency as intelligence updates are made, new weapons are introduced and new theaters of operation are identified. Second, the threat system interaction on a distributed network must be coordinated. The individualized nature of current threat systems precludes the possibility of introducing coordinated threats. The Distributed Mission Training Integrated Threat Environment (DMTITE) project is developing an effective solution to these issues. The DMTITE project is identifying the requirements for a distributed threat environment and building a demonstrator DOD High Level Architecture compatible system that can provide realistic threats for pilots to train against. The DMTITE prototype will instantiate a variety of threats for use in distributed training scenarios, including surface threats, air threats, radars, and jamming systems. A key element of the system will be the provision of realistic behaviors for the threat systems. We based DMTITE on a general software design methodology and software architecture for computer-generated forces (CGFs) that naturally supports `variety

  2. A Lesson Not to Be Learned? Understanding Stereotype Threat Does Not Protect Women from Stereotype Threat

    Science.gov (United States)

    Tomasetto, Carlo; Appoloni, Sara

    2013-01-01

    This research examines whether reading a text presenting scientific evidence concerning the phenomenon of stereotype threat improves or disrupts women's performance in a subsequent math task. In two experimental conditions participants (N=118 ) read a text summarizing an experiment in which stereotypes, and not biological differences, were shown…

  3. Feeling the Threat: Stereotype Threat as a Contextual Barrier to Women's Science Career Choice Intentions

    Science.gov (United States)

    Deemer, Eric D.; Thoman, Dustin B.; Chase, Justin P.; Smith, Jessi L.

    2014-01-01

    Social cognitive career theory (SCCT; Lent, Brown, & Hackett, 1994, 2000) holds that contextual barriers inhibit self-efficacy and goal choice intentions from points both near and far from the active career development situation. The current study examined the influence of one such proximal barrier, stereotype threat, on attainment of these…

  4. Threats Management Throughout the Software Service Life-Cycle

    Directory of Open Access Journals (Sweden)

    Erlend Andreas Gjære

    2014-04-01

    Full Text Available Software services are inevitably exposed to a fluctuating threat picture. Unfortunately, not all threats can be handled only with preventive measures during design and development, but also require adaptive mitigations at runtime. In this paper we describe an approach where we model composite services and threats together, which allows us to create preventive measures at design-time. At runtime, our specification also allows the service runtime environment (SRE to receive alerts about active threats that we have not handled, and react to these automatically through adaptation of the composite service. A goal-oriented security requirements modelling tool is used to model business-level threats and analyse how they may impact goals. A process flow modelling tool, utilising Business Process Model and Notation (BPMN and standard error boundary events, allows us to define how threats should be responded to during service execution on a technical level. Throughout the software life-cycle, we maintain threats in a centralised threat repository. Re-use of these threats extends further into monitoring alerts being distributed through a cloud-based messaging service. To demonstrate our approach in practice, we have developed a proof-of-concept service for the Air Traffic Management (ATM domain. In addition to the design-time activities, we show how this composite service duly adapts itself when a service component is exposed to a threat at runtime.

  5. Identifying key conservation threats to Alpine birds through expert knowledge.

    Science.gov (United States)

    Chamberlain, Dan E; Pedrini, Paolo; Brambilla, Mattia; Rolando, Antonio; Girardello, Marco

    2016-01-01

    Alpine biodiversity is subject to a range of increasing threats, but the scarcity of data for many taxa means that it is difficult to assess the level and likely future impact of a given threat. Expert opinion can be a useful tool to address knowledge gaps in the absence of adequate data. Experts with experience in Alpine ecology were approached to rank threat levels for 69 Alpine bird species over the next 50 years for the whole European Alps in relation to ten categories: land abandonment, climate change, renewable energy, fire, forestry practices, grazing practices, hunting, leisure, mining and urbanization. There was a high degree of concordance in ranking of perceived threats among experts for most threat categories. The major overall perceived threats to Alpine birds identified through expert knowledge were land abandonment, urbanization, leisure and forestry, although other perceived threats were ranked highly for particular species groups (renewable energy and hunting for raptors, hunting for gamebirds). For groups of species defined according to their breeding habitat, open habitat species and treeline species were perceived as the most threatened. A spatial risk assessment tool based on summed scores for the whole community showed threat levels were highest for bird communities of the northern and western Alps. Development of the approaches given in this paper, including addressing biases in the selection of experts and adopting a more detailed ranking procedure, could prove useful in the future in identifying future threats, and in carrying out risk assessments based on levels of threat to the whole bird community.

  6. A reference region for the Ordovician-Silurian boundary: the Oued In Djerane, Algerian SaharaUne région de référence pour la limite Ordovicien-Silurien : l'Oued In Djerane, Sahara algérien

    Science.gov (United States)

    Legrand, Philippe

    2000-01-01

    The melting chronology of the Latest Ordovician inlandsis takes on a particular importance in northern Gondwana. A continuous sequence of Diplograptid range zones has been defined from outcrops in the Oued In Djerane, but its comparison with the sequence observed in the stratotype of the Silurian-Ordovician boundary is problematic because of the endemic character of the Saharan species. Moreover, some difficulties are linked to the definition of the Ordovician-Silurian boundary, which, in the Algerian Sahara, probably lies in the Pseudorthograptus (?) kiliani zone. A definite regional diachronism in the melting of the ice-cap has also been confirmed.

  7. Screening for Genes Coding for Putative Antitumor Compounds, Antimicrobial and Enzymatic Activities from Haloalkalitolerant and Haloalkaliphilic Bacteria Strains of Algerian Sahara Soils

    Directory of Open Access Journals (Sweden)

    Okba Selama

    2014-01-01

    Full Text Available Extreme environments may often contain unusual bacterial groups whose physiology is distinct from those of normal environments. To satisfy the need for new bioactive pharmaceuticals compounds and enzymes, we report here the isolation of novel bacteria from an extreme environment. Thirteen selected haloalkalitolerant and haloalkaliphilic bacteria were isolated from Algerian Sahara Desert soils. These isolates were screened for the presence of genes coding for putative antitumor compounds using PCR based methods. Enzymatic, antibacterial, and antifungal activities were determined by using cultural dependant methods. Several of these isolates are typical of desert and alkaline saline soils, but, in addition, we report for the first time the presence of a potential new member of the genus Nocardia with particular activity against the yeast Saccharomyces cerevisiae. In addition to their haloalkali character, the presence of genes coding for putative antitumor compounds, combined with the antimicrobial activity against a broad range of indicator strains and their enzymatic potential, makes them suitable for biotechnology applications.

  8. PALEODRAINAGES OF THE EASTERN SAHARA - THE RADAR RIVERS REVISITED (SIR - A/B IMPLICATIONS FOR A MID - TERTIARY TRANS - AFRICAN DRAINAGE SYSTEM).

    Science.gov (United States)

    McCauley, John F.; Breed, Carlos S.; Schaber, Gerald G.; McHugh, William P.; Issawi, Bahay; Haynes, C. Vance; Grolier, Maurice J.; El Kilani, Ali

    1986-01-01

    A complex history of Cenozoic fluvial activity in the presently hyperarid eastern Sahara is inferred from Shuttle Imaging Radar (SIR) data and postflight field investigations in southwest Egypt and northwest Sudan. SIR images were coregistered with Landsat and existing maps as a guide to exploration of the buried paleodrainages (radar rivers) first discovered by SIR-A. Field observations explain the radar responses of three types of radar rivers: RR-1, RR-2, and RR-3. A generalized model of the radar rivers, based on field studies and regional geologic relations, shows apparent changes in river regimen since the large valleys were established during the late Paleogene-early Neogene eras. SIR-based mapping of these paleodrainages, although incomplete, reveals missing links in an area once thought to be devoid of master streams.

  9. The formation conditions of enstatite chondrites: Insights from trace element geochemistry of olivine-bearing chondrules in Sahara 97096 (EH3)

    CERN Document Server

    Jacquet, Emmanuel; Gounelle, Matthieu

    2016-01-01

    We report in situ LA-ICP-MS trace element analyses of silicate phases in olivine-bearing chondrules in the Sahara 97096 (EH3) enstatite chondrite. Most olivine and enstatite present rare earth element (REE) patterns comparable to their counterparts in type I chondrules in ordinary chondrites. They thus likely share a similar igneous origin, likely under similar redox conditions. The mesostasis however frequently shows negative Eu and/or Yb (and more rarely Sm) anomalies, evidently out of equilibrium with olivine and enstatite. We suggest that this reflects crystallization of oldhamite during a sulfidation event, already inferred by others, during which the mesostasis was molten, where the complementary positive Eu and Yb anomalies exhibited by oldhamite would have possibly arisen due to a divalent state of these elements. Much of this igneous oldhamite would have been expelled from the chondrules, presumably by inertial acceleration or surface tension effects, and would have contributed to the high abundance ...

  10. Screening for genes coding for putative antitumor compounds, antimicrobial and enzymatic activities from haloalkalitolerant and haloalkaliphilic bacteria strains of Algerian Sahara Soils.

    Science.gov (United States)

    Selama, Okba; Amos, Gregory C A; Djenane, Zahia; Borsetto, Chiara; Laidi, Rabah Forar; Porter, David; Nateche, Farida; Wellington, Elizabeth M H; Hacène, Hocine

    2014-01-01

    Extreme environments may often contain unusual bacterial groups whose physiology is distinct from those of normal environments. To satisfy the need for new bioactive pharmaceuticals compounds and enzymes, we report here the isolation of novel bacteria from an extreme environment. Thirteen selected haloalkalitolerant and haloalkaliphilic bacteria were isolated from Algerian Sahara Desert soils. These isolates were screened for the presence of genes coding for putative antitumor compounds using PCR based methods. Enzymatic, antibacterial, and antifungal activities were determined by using cultural dependant methods. Several of these isolates are typical of desert and alkaline saline soils, but, in addition, we report for the first time the presence of a potential new member of the genus Nocardia with particular activity against the yeast Saccharomyces cerevisiae. In addition to their haloalkali character, the presence of genes coding for putative antitumor compounds, combined with the antimicrobial activity against a broad range of indicator strains and their enzymatic potential, makes them suitable for biotechnology applications.

  11. When threats foreign turn domestic: Two ways for distant realistic intergroup threats to carry over into local intolerance.

    Science.gov (United States)

    Bouman, Thijs; van Zomeren, Martijn; Otten, Sabine

    2015-09-01

    In times of economic downturn, perceived realistic intergroup threats (e.g., labour competition) often dominate political and media discourse. Although local outgroups (e.g., local immigrants) can be experienced as sources of realistic threats, we propose that such threats can also be perceived to be caused by distant outgroups (e.g., European Union members perceiving Greece to threaten their economies) and that such distant threats can carry over into local intolerance (e.g., increasing intolerance towards local immigrant groups). We predicted and found in two studies that perceived distant realistic threats carried over into local intolerance via two different pathways. First, direct reactions towards the distant outgroup can generalize to culturally similar local outgroups (the group-based association pathway). Secondly, Study 2 indicated that when the distant threat was attributed to stereotypical outgroup traits (e.g., being lazy), distant realistic threats activated local realistic threats, which subsequently influenced local intolerance (the threat-based association pathway). Taken together, our studies indicate that perceived realistic threats foreign can turn domestic, but in two different ways.

  12. Threat-Related Information Suggests Competence: A Possible Factor in the Spread of Rumors.

    Directory of Open Access Journals (Sweden)

    Pascal Boyer

    Full Text Available Information about potential danger is a central component of many rumors, urban legends, ritual prescriptions, religious prohibitions and witchcraft crazes. We investigate a potential factor in the cultural success of such material, namely that a source of threat-related information may be intuitively judged as more competent than a source that does not convey such information. In five studies, we asked participants to judge which of two sources of information, only one of which conveyed threat-related information, was more knowledgeable. Results suggest that mention of potential danger makes a source appear more competent than others, that the effect is not due to a general negativity bias, and that it concerns competence rather than a more generally positive evaluation of the source.

  13. Impaired Retrieval Inhibition of Threat Material in Generalized Anxiety Disorder.

    Science.gov (United States)

    Kircanski, Katharina; Johnson, Douglas C; Mateen, Maria; Bjork, Robert A; Gotlib, Ian H

    2016-03-01

    Generalized Anxiety Disorder (GAD) is characterized by cognitive biases toward threat-relevant information, but the underlying mechanisms are unclear. We translated a retrieval-practice paradigm from cognitive science to investigate impaired inhibition of threat information as one such mechanism. Participants diagnosed with GAD and never-disordered control participants learned a series of cue-target pairs; whereas some cues were associated only with neutral targets, others were associated with both neutral and threat targets. Next, participants practiced retrieving neutral targets, which typically suppresses the subsequent recall of unpracticed associated targets (retrieval-induced forgetting; RIF). Finally, participants were tested on their recall of all targets. Despite showing intact RIF of neutral targets, the GAD group failed to exhibit RIF of threat targets. Furthermore, within the GAD group, less RIF of threat targets correlated with greater pervasiveness of worry. Deficits in inhibitory control over threat-relevant information may underlie the cognitive pathology of GAD, which has important treatment implications.

  14. Prejudice towards Muslims in The Netherlands: testing integrated threat theory.

    Science.gov (United States)

    Velasco González, Karina; Verkuyten, Maykel; Weesie, Jeroen; Poppe, Edwin

    2008-12-01

    This study uses integrated threat theory to examine Dutch adolescents' (N=1,187) prejudice towards Muslim minorities. One out of two participants was found to have negative feelings towards Muslims. Perceived symbolic and realistic threat and negative stereotypes were examined as mediators between antecedent factors (in-group identification, intergroup contact, and the endorsement of multiculturalism) and prejudice. Based on structural equation modelling, it was found that stereotypes and symbolic threats, but not realistic threats, predicted prejudice towards Muslims. Further, it was found that the effect of in-group identification on prejudice was fully mediated by symbolic threat, the effect of contact was partially mediated by stereotypes, and the effect of the endorsement of multiculturalism was mediated by both symbolic threat and stereotypes. In addition, contact and multiculturalism were directly associated with prejudice towards Muslims. The theoretical and practical implications of these findings are discussed.

  15. Air Target Fuzzy Pattern Recognition Threat-Judgment Model

    Institute of Scientific and Technical Information of China (English)

    童幼堂; 王建明

    2003-01-01

    Threat-judgment is a complicated fuzzy inference problem. Up to now no relevant unified theory and measuring standard have been developed. It is very difficult to establish a threat-judgment model with high reliability in the air defense system for the naval warships. Air target threat level judgment is an important component in naval warship combat command decision-making systems. According to the threat level judgment of air targets during the air defense of single naval warship, a fuzzy pattern recognition model for judging the threat from air targets is established. Then an algorithm for identifying the parameters in the model is presented. The model has an adaptive feature and can dynamically update its parameters according to the state change of the attacking targets and the environment. The method presented here can be used for the air defense system threat judgment in the naval warships.

  16. When anticipation beats accuracy: Threat alters memory for dynamic scenes.

    Science.gov (United States)

    Greenstein, Michael; Franklin, Nancy; Martins, Mariana; Sewack, Christine; Meier, Markus A

    2016-05-01

    Threat frequently leads to the prioritization of survival-relevant processes. Much of the work examining threat-related processing advantages has focused on the detection of static threats or long-term memory for details. In the present study, we examined immediate memory for dynamic threatening situations. We presented participants with visually neutral, dynamic stimuli using a representational momentum (RM) paradigm, and manipulated threat conceptually. Although the participants in both the threatening and nonthreatening conditions produced classic RM effects, RM was stronger for scenarios involving threat (Exps. 1 and 2). Experiments 2 and 3 showed that this effect does not generalize to the nonthreatening objects within a threatening scene, and that it does not extend to arousing happy situations. Although the increased RM effect for threatening objects by definition reflects reduced accuracy, we argue that this reduced accuracy may be offset by a superior ability to predict, and thereby evade, a moving threat.

  17. Females that experience threat are better teachers.

    Science.gov (United States)

    Kleindorfer, Sonia; Evans, Christine; Colombelli-Négrel, Diane

    2014-05-01

    Superb fairy-wren (Malurus cyaneus) females use an incubation call to teach their embryos a vocal password to solicit parental feeding care after hatching. We previously showed that high call rate by the female was correlated with high call similarity in fairy-wren chicks, but not in cuckoo chicks, and that parent birds more often fed chicks with high call similarity. Hosts should be selected to increase their defence behaviour when the risk of brood parasitism is highest, such as when cuckoos are present in the area. Therefore, we experimentally test whether hosts increase call rate to embryos in the presence of a singing Horsfield's bronze-cuckoo (Chalcites basalis). Female fairy-wrens increased incubation call rate when we experimentally broadcast cuckoo song near the nest. Embryos had higher call similarity when females had higher incubation call rate. We interpret the findings of increased call rate as increased teaching effort in response to a signal of threat.

  18. Affective signals of threat increase perceived proximity.

    Science.gov (United States)

    Cole, Shana; Balcetis, Emily; Dunning, David

    2013-01-01

    Do stimuli appear to be closer when they are more threatening? We tested people's perceptions of distance to stimuli that they felt were threatening relative to perceptions of stimuli they felt were disgusting or neutral. Two studies demonstrated that stimuli that emitted affective signals of threat (e.g., an aggressive male student) were seen as physically closer than stimuli that emitted affective signals of disgust (e.g., a repulsive male student) or no affective signal. Even after controlling for the direct effects of physiological arousal, object familiarity, and intensity of the negative emotional reaction, we found that threatening stimuli appeared to be physically closer than did disgusting ones (Study 2). These findings highlight the links among biased perception, action regulation, and successful navigation of the environment.

  19. Zika Virus: Old Rival, New Threat

    Directory of Open Access Journals (Sweden)

    Huanyu Wang

    2016-04-01

    Full Text Available Zika virus (ZIKV, originally isolated in 1947, caused a worldwide epidemic between January 2014 and February 2016 in which a total of 39 countries have reported autochthonous circulation (33 or indirect evidence of local transmission (6. The total area affected by ZIKV infection is expanding steadily. ZIKV has become a new threat to public health, and the recent cluster of microcephaly and other neurologic disorders suspected to be due to ZIKV has lead the World Health Organization to announce that it is a Public Health Emergency of International Concern. Because of its current importance, this review summarizes the currently available data on the etiology, epidemiology, clinical features, laboratory diagnosis, and transmission of ZIKV and its related diseases.

  20. Threats from space: 20 years of progress

    CERN Document Server

    Remo, J L

    2014-01-01

    It has been 20 years since planning began for the 1995 United Nations International Conference on Near-Earth Objects. The conference proceedings established the scientific basis for an international organizational framework to support research and collective actions to mitigate a potential near-Earth object (NEO) threat to the planet. Since that time, researchers have conducted telescope surveys that should, within the coming decade, answer many questions about the size, number, and Earth impact probability of these objects. Space explorations to asteroids and comets have been successfully carried out, including sample recovery. Laboratory experiments and computer simulations at Sandia National Laboratories have analyzed the effects of soft X-ray radiation on meteorites - which might help researchers develop a way to redirect an incoming asteroid by vaporizing a thin layer of its surface. An Action Team on NEOs, established in 2001 in response to recommendations of the Third United Nations Conference on the E...

  1. Scientific performance estimation of robustness and threat

    Science.gov (United States)

    Hoffman, John R.; Sorensen, Eric; Stelzig, Chad A.; Mahler, Ronald P. S.; El-Fallah, Adel I.; Alford, Mark G.

    2002-07-01

    For the last three years at this conference we have been describing the implementation of a unified, scientific approach to performance estimation for various aspects of data fusion: multitarget detection, tracking, and identification algorithms; sensor management algorithms; and adaptive data fusion algorithms. The proposed approach is based on finite-set statistics (FISST), a generalization of conventional statistics to multisource, multitarget problems. Finite-set statistics makes it possible to directly extend Shannon-type information metrics to multisource, multitarget problems in such a way that information can be defined and measured even though any given end-user may have conflicting or even subjective definitions of what informative means. In this presentation, we will show how to extend our previous results to two new problems. First, that of evaluating the robustness of multisensor, multitarget algorithms. Second, that of evaluating the performance of multisource-multitarget threat assessment algorithms.

  2. The insider threat--a new aspect of biosecurity.

    Science.gov (United States)

    Engells, Thomas E

    2013-01-01

    The need for those responsible for security at hospital research centers to take steps to counter insider threats to use biomedical and microbiological research and for perverted purposes is real, says the author. He spells out what the threats consist of suspicious behaviors to be aware of and reporting procedures for effective resolution that will enable life science researchers and law enforcement to successfully work together to thwart such threats.

  3. Postural threat influences vestibular-evoked muscular responses.

    Science.gov (United States)

    Lim, Shannon B; Cleworth, Taylor W; Horslen, Brian C; Blouin, Jean-Sébastien; Inglis, J Timothy; Carpenter, Mark G

    2017-02-01

    Standing balance is significantly influenced by postural threat. While this effect has been well established, the underlying mechanisms of the effect are less understood. The involvement of the vestibular system is under current debate, and recent studies that investigated the effects of height-induced postural threat on vestibular-evoked responses provide conflicting results based on kinetic (Horslen BC, Dakin CJ, Inglis JT, Blouin JS, Carpenter MG. J Physiol 592: 3671-3685, 2014) and kinematic (Osler CJ, Tersteeg MC, Reynolds RF, Loram ID. Eur J Neurosci 38: 3239-3247, 2013) data. We examined the effect of threat of perturbation, a different form of postural threat, on coupling (cross-correlation, coherence, and gain) of the vestibulo-muscular relationship in 25 participants who maintained standing balance. In the "No-Threat" conditions, participants stood quietly on a stable surface. In the "Threat" condition, participants' balance was threatened with unpredictable mediolateral support surface tilts. Quiet standing immediately before the surface tilts was compared to an equivalent time from the No-Threat conditions. Surface EMG was recorded from bilateral trunk, hip, and leg muscles. Hip and leg muscles exhibited significant increases in peak cross-correlation amplitudes, coherence, and gain (1.23-2.66×) in the Threat condition compared with No-Threat conditions, and significant correlations were observed between threat-related changes in physiological arousal and medium-latency peak cross-correlation amplitude in medial gastrocnemius (r = 0.408) muscles. These findings show a clear threat effect on vestibular-evoked responses in muscles in the lower body, with less robust effects of threat on trunk muscles. Combined with previous work, the present results can provide insight into observed changes during balance control in threatening situations.

  4. The Reliability to Predict Threat in Social Networks

    Directory of Open Access Journals (Sweden)

    Aleksandrs Larionovs

    2014-11-01

    Full Text Available During the analysis and study it will be possible to create and describe information damping mechanism for transition of threats from one user group to another (within the parameters of portraits, which is the main cause of the massively spreading threat on social networks. Threat predictability in social networks is associated with an adequate scrutiny of system and user portrait, which has a direct correlation.

  5. Stereotype threat in salary negotiations is mediated by reservation salary.

    Science.gov (United States)

    Tellhed, Una; Björklund, Fredrik

    2011-04-01

    Women are stereotypically perceived as worse negotiators than men, which may make them ask for less salary than men when under stereotype threat (Kray et al., 2001). However, the mechanisms of stereotype threat are not yet properly understood. The current study investigated whether stereotype threat effects in salary negotiations can be explained by motivational factors. A total of 116 business students negotiated salary with a confederate and were either told that this was diagnostic of negotiating ability (threat manipulation) or not. Measures of minimum (reservation) and ideal (aspiration) salary goals and regulatory focus were collected. The finding (Kray et al., 2001) that women make lower salary requests than men when under stereotype threat was replicated. Women in the threat condition further reported lower aspiration salary, marginally significantly lower reservation salary and less eagerness/more vigilance than men. Reservation salary mediated the stereotype threat effect, and there was a trend for regulatory focus to mediate the effect. Thus, reservation salary partly explains why women ask for less salary than men under stereotype threat. Female negotiators may benefit from learning that stereotype threat causes sex-differences in motivation.

  6. Working Memory Regulates Trait Anxiety-Related Threat Processing Biases.

    Science.gov (United States)

    Booth, Robert W; Mackintosh, Bundy; Sharma, Dinkar

    2016-12-19

    High trait anxious individuals tend to show biased processing of threat. Correlational evidence suggests that executive control could be used to regulate such threat-processing. On this basis, we hypothesized that trait anxiety-related cognitive biases regarding threat should be exaggerated when executive control is experimentally impaired by loading working memory. In Study 1, 68 undergraduates read ambiguous vignettes under high and low working memory load; later, their interpretations of these vignettes were assessed via a recognition test. Trait anxiety predicted biased interpretation of social threat vignettes under high working memory load, but not under low working memory load. In Study 2, 53 undergraduates completed a dot probe task with fear-conditioned Japanese characters serving as threat stimuli. Trait anxiety predicted attentional bias to the threat stimuli but, again, this only occurred under high working memory load. Interestingly however, actual eye movements toward the threat stimuli were only associated with state anxiety, and this was not moderated by working memory load, suggesting that executive control regulates biased threat-processing downstream of initial input processes such as orienting. These results suggest that cognitive loads can exacerbate trait anxiety-related cognitive biases, and therefore represent a useful tool for assessing cognitive biases in future research. More importantly, since biased threat-processing has been implicated in the etiology and maintenance of anxiety, poor executive control may be a risk factor for anxiety disorders. (PsycINFO Database Record

  7. Stereotype Threat Alters the Subjective Experience of Memory.

    Science.gov (United States)

    Mazerolle, Marie; Régner, Isabelle; Rigalleau, François; Huguet, Pascal

    2015-01-01

    There is now evidence that negative age-related stereotypes about memory reduce older adults' memory performance, and inflate age differences in this domain. Here, we examine whether stereotype threat may also influence the basic feeling that one is more or less able to remember. Using the Remember/Know paradigm, we demonstrated that stereotype threat conducted older adults to a greater feeling of familiarity with events, while failing to retrieve any contextual detail. This finding indicates that stereotype threat alters older adults' subjective experience of memory, and strengthens our understanding of the mechanisms underlying stereotype threat effects.

  8. Wetland Preservation in Australia: The Administrative and Policital Threats

    Institute of Scientific and Technical Information of China (English)

    Mark Yaolin Wang

    2008-01-01

    The wetlands in Australia are of great physical, chemical and biological variety due to the continent's age, geological history and climate. The traditional physical and biological threats remain as the main challenges for wetland preservation in Australia. However, it has been increasingly recognized that the immediate survival of wetlands are being affected by more subtle threats, such as administrative and political threats. This paper identifies these non-physical threats and discusses how and why they have become the major barriers for sustainable wetland preservation in Australia. Finally, this paper calls for more practical policies and solutions to be implemented for sustainable wetland preservation in Australia.

  9. Mechanisms of visual threat detection in specific phobia.

    Science.gov (United States)

    Weierich, Mariann R; Treat, Teresa A

    2015-01-01

    People with anxiety or stress-related disorders attend differently to threat-relevant compared with non-threat stimuli, yet the temporal mechanisms of differential allocation of attention are not well understood. We investigated two independent mechanisms of temporal processing of visual threat by comparing spider-phobic and non-fearful participants using a rapid serial visual presentation task. Consistent with prior literature, spider phobics, but not non-fearful controls, displayed threat-specific facilitated detection of spider stimuli relative to negative stimuli and neutral stimuli. Further, signal detection analyses revealed that facilitated threat detection in spider-phobic participants was driven by greater sensitivity to threat stimulus features and a trend towards a lower threshold for detecting spider stimuli. However, phobic participants did not display reliably slowed temporal disengagement from threat-relevant stimuli. These findings advance our understanding of threat feature processing that might contribute to the onset and maintenance of symptoms in specific phobia and disorders that involve visual threat information more generally.

  10. Temperature profiles from STD casts from the Spanish Sahara from NOAA Ship OCEANOGRAPHER as part of the International Decade of Ocean Exploration / Coastal Upwelling Ecosystems Analysis (IDOE/CUEA) from 1974-03-08 to 1974-05-01 (NCEI Accession 9800112)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profiles were collected from STD casts off the Spanish Sahara from NOAA Ship OCEANOGRAPHER from 08 March 1974 to 01 May 1974. Data were collected by the...

  11. Threats to sandy beach ecosystems: A review

    Science.gov (United States)

    Defeo, Omar; McLachlan, Anton; Schoeman, David S.; Schlacher, Thomas A.; Dugan, Jenifer; Jones, Alan; Lastra, Mariano; Scapini, Felicita

    2009-01-01

    We provide a brief synopsis of the unique physical and ecological attributes of sandy beach ecosystems and review the main anthropogenic pressures acting on the world's single largest type of open shoreline. Threats to beaches arise from a range of stressors which span a spectrum of impact scales from localised effects (e.g. trampling) to a truly global reach (e.g. sea-level rise). These pressures act at multiple temporal and spatial scales, translating into ecological impacts that are manifested across several dimensions in time and space so that today almost every beach on every coastline is threatened by human activities. Press disturbances (whatever the impact source involved) are becoming increasingly common, operating on time scales of years to decades. However, long-term data sets that describe either the natural dynamics of beach systems or the human impacts on beaches are scarce and fragmentary. A top priority is to implement long-term field experiments and monitoring programmes that quantify the dynamics of key ecological attributes on sandy beaches. Because of the inertia associated with global climate change and human population growth, no realistic management scenario will alleviate these threats in the short term. The immediate priority is to avoid further development of coastal areas likely to be directly impacted by retreating shorelines. There is also scope for improvement in experimental design to better distinguish natural variability from anthropogenic impacts. Sea-level rise and other effects of global warming are expected to intensify other anthropogenic pressures, and could cause unprecedented ecological impacts. The definition of the relevant scales of analysis, which will vary according to the magnitude of the impact and the organisational level under analysis, and the recognition of a physical-biological coupling at different scales, should be included in approaches to quantify impacts. Zoning strategies and marine reserves, which have not

  12. International Illegal Trade in Wildlife: Threats and U.S. Policy

    Science.gov (United States)

    2008-08-22

    Actual and potential locations identified by the State Department include Somalia; the Trans-Sahara, including Mali, Mauritania, Niger, Algeria , and...Living Resources. Antarctic marine living resources include finfish, mollusks, crustaceans , and all other species of living organisms, including birds...The statute applies only to wild mammals, birds, fish, amphibians, reptiles, mollusks, and crustaceans . It does not apply, for example, to insects

  13. Threat Detection in Tweets with Trigger Patterns and Contextual Cues

    NARCIS (Netherlands)

    Spitters, M.M.; Eendebak, P.T.; Worm, D.T.H.; Bouma, H.

    2014-01-01

    Many threats in the real world can be related to activities in open sources on the internet. Early detection of threats based on internet information could assist in the prevention of incidents. However, the amount of data in social media, blogs and forums rapidly increases and it is time consuming

  14. Investigating Hypervigilance for Social Threat of Lonely Children

    Science.gov (United States)

    Qualter, Pamela; Rotenberg, Ken; Barrett, Louise; Henzi, Peter; Barlow, Alexandra; Stylianou, Maria; Harris, Rebecca A.

    2013-01-01

    The hypothesis that lonely children show hypervigilance for social threat was examined in a series of three studies that employed different methods including advanced eye-tracking technology. Hypervigilance for social threat was operationalized as hostility to ambiguously motivated social exclusion in a variation of the hostile attribution…

  15. Threats and protection for electronically-steered array radars

    NARCIS (Netherlands)

    Janssen, J.P.B.; Monni, S.; Maas, A.P.M.; Vliet, F.E. van

    2008-01-01

    Front-end power overload protection is a vital issue in any electro-magnetic sensor. The issues around active electronically-steered arrays are more recent and pose new threats. Different categories of threats can damage the sensitive electronics in the phased-array radar, like hostile high power el

  16. Anxiety and threat perception abnormalities in normal children.

    NARCIS (Netherlands)

    P. Muris; M. Kindt; S. Boegels; H. Merckelbach; B, Gadet; V. Moulaert

    2000-01-01

    Examined the relationship between childhood anxiety and threat perception abnormalities. 105 children (aged 8-13 yrs) were exposed to stories reflecting 3 types of anxiety: social anxiety, separation anxiety, and generalized anxiety. From children's reactions to the stories, a number of threat perce

  17. A Stereotype Threat Account of Boys' Academic Underachievement

    Science.gov (United States)

    Hartley, Bonny L.; Sutton, Robbie M.

    2013-01-01

    Three studies examined the role of stereotype threat in boys' academic underachievement. Study 1 (children aged 4-10, n = 238) showed that girls from age 4 years and boys from age 7 years believed, and thought adults believed, that boys are academically inferior to girls. Study 2 manipulated stereotype threat, informing children aged…

  18. Of guns and snakes: testing a modern threat superiority effect.

    Science.gov (United States)

    Subra, Baptiste; Muller, Dominique; Fourgassie, Lisa; Chauvin, Alan; Alexopoulos, Theodore

    2017-02-03

    Previous studies suggest that ancient (i.e. evolutionary-based) threats capture attention because human beings possess an inborn module shaped by evolution and dedicated to their detection. An alternative account proposes that a key feature predicting whether a stimulus will capture attention is its relevance rather than its ontology (i.e. phylogenetic or ontogenetic threat). Within this framework, the present research deals with the attentional capture by threats commonly encountered in our urban environment. In two experiments, we investigate the attentional capture by modern threats (i.e. weapons). In Experiment 1, participants responded to a target preceded by a cue, which was a weapon or a non-threatening stimulus. We found a larger cuing effect (faster reaction times to valid vs. invalid trials) with weapons as compared with non-threatening cues. In Experiment 2, modern (e.g. weapons) and ancient threats (e.g. snakes) were pitted against one another as cues to determine which ones preferentially capture attention. Crucially, participants were faster to detect a target preceded by a modern as opposed to an ancient threat, providing initial evidence for a superiority of modern threat. Overall, the present findings appear more consistent with a relevance-based explanation rather than an evolutionary-based explanation of threat detection.

  19. An examination of stereotype threat effects on girls' mathematics performance.

    Science.gov (United States)

    Ganley, Colleen M; Mingle, Leigh A; Ryan, Allison M; Ryan, Katherine; Vasilyeva, Marina; Perry, Michelle

    2013-10-01

    Stereotype threat has been proposed as 1 potential explanation for the gender difference in standardized mathematics test performance among high-performing students. At present, it is not entirely clear how susceptibility to stereotype threat develops, as empirical evidence for stereotype threat effects across the school years is inconsistent. In a series of 3 studies, with a total sample of 931 students, we investigated stereotype threat effects during childhood and adolescence. Three activation methods were used, ranging from implicit to explicit. Across studies, we found no evidence that the mathematics performance of school-age girls was impacted by stereotype threat. In 2 of the studies, there were gender differences on the mathematics assessment regardless of whether stereotype threat was activated. Potential reasons for these findings are discussed, including the possibility that stereotype threat effects only occur in very specific circumstances or that they are in fact occurring all the time. We also address the possibility that the literature regarding stereotype threat in children is subject to publication bias.

  20. Personality, threat and affective responses to cultural diversity

    NARCIS (Netherlands)

    Van der Zee, Karen; Van der Gang, Ineke

    2007-01-01

    The present study tried to reconcile assumptions from Terror Management Theory that individual differences in openness to diversity are enhanced by existential threat with own recent findings suggesting that individual differences are diminished by threat. A model was supported assuming that it is t

  1. Overview of the Threat Posed by Insiders to Critical Assets

    Science.gov (United States)

    2013-08-08

    cyber threats. Managing The Insider Threat: What Every Organization Should Know Twitter #CERTinsiderthreat © 2013 Carnegie Mellon University...Concealing Indicators and Violations S O B4 concealing rule violations due to organization sanctions O O O Addiction to Financial Gain Initial Satisfaction

  2. Coping with threats of terrorism: a protocol for group intervention.

    Science.gov (United States)

    Ottenstein, Richard J

    2003-01-01

    This article presents a group protocol designed to assist people in coping with direct and ongoing threats of terrorism. The protocol is intended to enable participants to address the psychological issues necessary to cope during periods of extreme threat. A step-by-step description of the protocol is provided.

  3. Asymmetric Threat Assessment Using Electro-Optical Image Systems

    NARCIS (Netherlands)

    Schwering, P.B.W.; Schutte, K.

    2010-01-01

    Asymmetric threat assessment from military platforms, including early detection and classification by electro-optical means, is a complicated matter. These threats can be for instance explosives-packed rubber boats, minecarrying swimmers and divers in a marine environment or terrorists, improvised e

  4. 41 CFR 60-300.22 - Direct threat defense.

    Science.gov (United States)

    2010-07-01

    ... 41 Public Contracts and Property Management 1 2010-07-01 2010-07-01 true Direct threat defense. 60-300.22 Section 60-300.22 Public Contracts and Property Management Other Provisions Relating to Public... VETERANS Discrimination Prohibited § 60-300.22 Direct threat defense. The contractor may use as...

  5. 41 CFR 60-250.22 - Direct threat defense.

    Science.gov (United States)

    2010-07-01

    ... 41 Public Contracts and Property Management 1 2010-07-01 2010-07-01 true Direct threat defense. 60-250.22 Section 60-250.22 Public Contracts and Property Management Other Provisions Relating to Public... VETERANS Discrimination Prohibited § 60-250.22 Direct threat defense. The contractor may use as...

  6. A Tale of Two Threats: Social Anxiety and Attention to Social Threat as a Function of Social Exclusion and Non-Exclusion Threats.

    Science.gov (United States)

    Buckner, Julia D; Dewall, C Nathan; Schmidt, Norman B; Maner, Jon K

    2010-10-01

    To attain and maintain social acceptance, people may attend to cues of possible social rejection or exclusion. Attention to such cues can be influenced by social anxiety. Two competing theories address social anxiety and attention: hypervigilance to versus avoidance of negative social cues. We propose a synthesis of these models such that, in the absence of social exclusion, socially anxious people may be hypervigilant to negative social cues. However, after experiencing social exclusion, they may avoid negative cues in favor of cues signaling social acceptance. Eyetracking was used to examine attention to negative, happy, and neutral faces after social exclusion threat or a non-exclusion threat (N = 27, 69.2% female). Fear of negative evaluation, a core component of social anxiety, was assessed using the Brief Fear of Negative Evaluation (BFNE) scale (Leary 1983). Among individuals with high BFNE, non-exclusion threat elicited greater attention toward negative faces than did social exclusion threat. However, social exclusion threat relative to non-exclusion threat was related to greater attention to positive faces among those with high BFNE. These effects were not observed among those with low BFNE. Thus, data provide preliminary support for a synthesized model.

  7. Unhealthy interactions: the role of stereotype threat in health disparities.

    Science.gov (United States)

    Aronson, Joshua; Burgess, Diana; Phelan, Sean M; Juarez, Lindsay

    2013-01-01

    Stereotype threat is the unpleasant psychological experience of confronting negative stereotypes about race, ethnicity, gender, sexual orientation, or social status. Hundreds of published studies show how the experience of stereotype threat can impair intellectual functioning and interfere with test and school performance. Numerous published interventions derived from this research have improved the performance and motivation of individuals targeted by low-ability stereotypes. Stereotype threat theory and research provide a useful lens for understanding and reducing the negative health consequences of interracial interactions for African Americans and members of similarly stigmatized minority groups. Here we summarize the educational outcomes of stereotype threat and examine the implications of stereotype threat for health and health-related behaviors.

  8. Personality and defensive reactions: fear, trait anxiety, and threat magnification.

    Science.gov (United States)

    Perkins, Adam M; Cooper, Andrew; Abdelall, Maura; Smillie, Luke D; Corr, Philip J

    2010-06-01

    The revised Reinforcement Sensitivity Theory (rRST) of personality (Gray & McNaughton, 2000) maintains that trait individual differences in the operation of defensive systems relate to facets of human personality, most notably anxiety and fear. We investigated this theory in 2 separate studies (total N=270) using a threat scenario research strategy (Blanchard, Hynd, Minke, Minemoto, & Blanchard, 2001). Consistent with rRST, results showed that individuals with high fear questionnaire scores tended to select defensive responses entailing orientation away from threat (e.g., run away) and that fear-prone individuals also tended to perceive threats as magnified. The extent of this threat magnification mediated the positive association observed between fear and orientation away from threat. Overall, results suggest that interindividual variance in defensive reactions is associated with a variety of existing personality constructs but that further research is required to determine the precise relationship between personality and defensive reactions.

  9. Perceived control qualifies the effects of threat on prejudice.

    Science.gov (United States)

    Greenaway, Katharine H; Louis, Winnifred R; Hornsey, Matthew J; Jones, Janelle M

    2014-09-01

    People sometimes show a tendency to lash out in a prejudiced manner when they feel threatened. This research shows that the relationship between threat and prejudice is moderated by people's levels of perceived control: Threat leads to prejudice only when people feel concurrently low in control. In two studies, terrorist threat was associated with heightened prejudice among people who were low in perceived control over the threat (Study 1; N = 87) or over their lives in general (Study 2; N = 2,394), but was not associated with prejudice among people who were high in perceived control. Study 3 (N = 139) replicated this finding experimentally in the context of the Global Financial Crisis. The research identifies control as an important ingredient in threatening contexts that, if bolstered, can reduce general tendencies to lash out under threat.

  10. Fructose; a Hidden Threat for Chronic Diseases

    Directory of Open Access Journals (Sweden)

    Ahmet Korkmaz

    2008-08-01

    Full Text Available Incremental usage of the fructose derived from corn by processed-food manufacturers has become a crucial threat in terms of human health. Although it is known as fruit sugar, the most important source of dietary fructose is now, processed-food prepared by using high-fructose corn syrup. Basically, fructose is metabolized within liver and its energy load is equal to glucose. Nevertheless, it does not make up satiety and fullness. Therefore, fructose-rich foods and beverages can be consumed in large amount because the absence of satiety. Studies performed recently unveil a connection between amount of fructose consumed and metabolic disorders such as cardiovascular diseases, type 2 diabetes, hypertension and obesity. The incidence of metabolic diseases which are already affecting more than half of the adults has been increasing among children. Moreover, these types of foods are generally consumed by children. Therefore, in order to reduce the frequency of metabolic disorders in all ages, the amount of fructose in processed-foods and beverages should also be taken into consideration. [TAF Prev Med Bull 2008; 7(4.000: 343-346

  11. Superluminous supernovae: No threat from Eta Carinae

    CERN Document Server

    Thomas, Brian C; Fields, Brian D; Anthony-Twarog, Barbara J

    2007-01-01

    Recently Supernova 2006gy was noted as the most luminous ever recorded, with a total radiated energy of ~10^44 Joules. It was proposed that the progenitor may have been a massive evolved star similar to Eta Carinae, which resides in our own galaxy at a (poorly determined) distance of ~2.5 kpc. Eta Carinae appears ready to detonate, and in fact had an outburst in 1843. Although it is too distant to pose a serious threat as a normal supernova, and given its rotation axis is unlikely to produce a Gamma Ray Burst oriented toward the Earth, Eta Carinae is about 30,000 times nearer than 2006gy, and we re-evaluate it as a potential superluminous supernova. We find that given the large ratio of emission in the optical to the X-ray, atmospheric effects are negligible. Ionization of the atmosphere and concomitant ozone depletion are unlikely to be important. Any cosmic ray effects should be spread out over ~10^4 y, and similarly unlikely to produce any serious perturbation to the biosphere. We also discuss a new possib...

  12. [Chikungunya fever - A new global threat].

    Science.gov (United States)

    Montero, Antonio

    2015-08-07

    The recent onset of epidemics caused by viruses such as Ebola, Marburg, Nipah, Lassa, coronavirus, West-Nile encephalitis, Saint Louis encephalitis, human immunodeficiency virus, dengue, yellow fever and Venezuelan hemorrhagic fever alerts about the risk these agents represent for the global health. Chikungunya virus represents a new threat. Surged from remote African regions, this virus has become endemic in the Indic ocean basin, the Indian subcontinent and the southeast of Asia, causing serious epidemics in Africa, Indic Ocean Islands, Asia and Europe. Due to their epidemiological and biological features and the global presence of their vectors, chikungunya represents a serious menace and could become endemic in the Americas. Although chikungunya infection has a low mortality rate, its high attack ratio may collapse the health system during epidemics affecting a sensitive population. In this paper, we review the clinical and epidemiological features of chikungunya fever as well as the risk of its introduction into the Americas. We remark the importance of the epidemiological control and mosquitoes fighting in order to prevent this disease from being introduced into the Americas.

  13. The nuclear threat; La menace nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Tertrais, Bruno

    2011-01-26

    For a long time, a small group of big powers has been the only holder of nuclear weapons (US, USSR, Great Britain, France and China). Since then, new weapons have come out on the geopolitical scene: Israel, India, Pakistan, and some others remain uncertain and generate a worrying atmosphere (North Korea, Iran..). But what is the real risk with nuclear proliferation? Should we dread about it? Is nuclear terrorism a real threat? What are the political stakes of nuclear weapons? Is disarmament a real solution? These are some of the questions that the author answers in a precise and clear manner in this book. Contents: 1 - from monopoly to proliferation: who owns nuclear weapons today, why is it so coveted, is it easy to make one?; 2 - the newcomers: what do we really know about the Iranian nuclear programme, Iran and North Korea: between negotiation and confrontation; 3 - international control and regulation: do we have reliable information, how do we know what we know, Iraq: was there a 'lie' somewhere, who are the states who have renounced nuclear weapons?; 4 - the future: is there still a nuclear warfare risk, what if Pakistani weapons fall into islamic hands, is nuclear terrorism a fantasy or a real risk?

  14. Ebola Virus ─ A Global Threat

    Directory of Open Access Journals (Sweden)

    Mejbah Uddin Ahmed

    2015-01-01

    Full Text Available Ebola virus is a filamentous, enveloped, non-segmented, single-stranded, negative-sense RNA virus. It belongs to the Filoviridae and was first recognized near the Ebola River valley in Zaire in 1976. Since then most of the outbreaks have occurred to both human and nonhuman primates in sub-Saharan Africa. Ebola virus causes highly fatal hemorrhagic fever in human and nonhuman primates. In addition to hemorrhagic fever, it could be used as a bioterrorism agent. Although its natural reservoir is yet to be proven, current data suggest that fruit bats are the possibility. Infection has also been documented through the handling of infected chimpanzees, gorillas, monkeys, forest antelope and porcupines. Human infection is caused through close contact with the blood, secretion, organ or other body fluids of infected animal. Human-to-human transmission is also possible. Ebola virus infections are characterized by immune suppression and a systemic inflammatory response that causes impairment of the vascular, coagulation, and immune systems, leading to multiorgan failure and shock. The virus constitutes an important public health threat in Africa and also worldwide as no effective treatment or vaccine is available till now

  15. Superluminous Supernovae: No Threat from Eta Carinae

    Science.gov (United States)

    Thomas, Brian; Melott, A. L.; Fields, B. D.; Anthony-Twarog, B. J.

    2008-05-01

    Recently Supernova 2006gy was noted as the most luminous ever recorded, with a total radiated energy of 1044 Joules. It was proposed that the progenitor may have been a massive evolved star similar to η Carinae, which resides in our own galaxy at a distance of about 2.3 kpc. η Carinae appears ready to detonate. Although it is too distant to pose a serious threat as a normal supernova, and given its rotation axis is unlikely to produce a Gamma-Ray Burst oriented toward the Earth, η Carinae is about 30,000 times nearer than 2006gy, and we re-evaluate it as a potential superluminous supernova. We find that given the large ratio of emission in the optical to the X-ray, atmospheric effects are negligible. Ionization of the atmosphere and concomitant ozone depletion are unlikely to be important. Any cosmic ray effects should be spread out over 104 y, and similarly unlikely to produce any serious perturbation to the biosphere. We also discuss a new possible effect of supernovae, endocrine disruption induced by blue light near the peak of the optical spectrum. This is a possibility for nearby supernovae at distances too large to be considered "dangerous” for other reasons. However, due to reddening and extinction by the interstellar medium, η Carinae is unlikely to trigger such effects to any significant degree.

  16. Identifying key conservation threats to Alpine birds through expert knowledge

    Directory of Open Access Journals (Sweden)

    Dan E. Chamberlain

    2016-02-01

    Full Text Available Alpine biodiversity is subject to a range of increasing threats, but the scarcity of data for many taxa means that it is difficult to assess the level and likely future impact of a given threat. Expert opinion can be a useful tool to address knowledge gaps in the absence of adequate data. Experts with experience in Alpine ecology were approached to rank threat levels for 69 Alpine bird species over the next 50 years for the whole European Alps in relation to ten categories: land abandonment, climate change, renewable energy, fire, forestry practices, grazing practices, hunting, leisure, mining and urbanization. There was a high degree of concordance in ranking of perceived threats among experts for most threat categories. The major overall perceived threats to Alpine birds identified through expert knowledge were land abandonment, urbanization, leisure and forestry, although other perceived threats were ranked highly for particular species groups (renewable energy and hunting for raptors, hunting for gamebirds. For groups of species defined according to their breeding habitat, open habitat species and treeline species were perceived as the most threatened. A spatial risk assessment tool based on summed scores for the whole community showed threat levels were highest for bird communities of the northern and western Alps. Development of the approaches given in this paper, including addressing biases in the selection of experts and adopting a more detailed ranking procedure, could prove useful in the future in identifying future threats, and in carrying out risk assessments based on levels of threat to the whole bird community.

  17. Safe from harm: learned, instructed, and symbolic generalization pathways of human threat-avoidance.

    Directory of Open Access Journals (Sweden)

    Simon Dymond

    Full Text Available Avoidance of threatening or unpleasant events is usually an adaptive behavioural strategy. Sometimes, however, avoidance can become chronic and lead to impaired daily functioning. Excessive threat-avoidance is a central diagnostic feature of anxiety disorders, yet little is known about whether avoidance acquired in the absence of a direct history of conditioning with a fearful event differs from directly learned avoidance. In the present study, we tested whether avoidance acquired indirectly via verbal instructions and symbolic generalization result in similar levels of avoidance behaviour and threat-beliefs to avoidance acquired after direct learning. Following fear conditioning in which one conditioned stimulus was paired with shock (CS+ and another was not (CS-, participants either learned or were instructed to make a response that cancelled impending shock. Three groups were then tested with a learned CS+ and CS- (learned group, instructed CS+ (instructed group, and generalized CS+ (derived group presentations. Results showed similar levels of avoidance behaviour and threat-belief ratings about the likelihood of shock across each of the three pathways despite the different mechanisms by which they were acquired. Findings have implications for understanding the aetiology of clinical avoidance in anxiety.

  18. The role of genomics in the identification, prediction, and prevention of biological threats.

    Science.gov (United States)

    Fricke, W Florian; Rasko, David A; Ravel, Jacques

    2009-10-01

    In all likelihood, it is only a matter of time before our public health system will face a major biological threat, whether intentionally dispersed or originating from a known or newly emerging infectious disease. It is necessary not only to increase our reactive "biodefense," but also to be proactive and increase our preparedness. To achieve this goal, it is essential that the scientific and public health communities fully embrace the genomic revolution, and that novel bioinformatic and computing tools necessary to make great strides in our understanding of these novel and emerging threats be developed. Genomics has graduated from a specialized field of science to a research tool that soon will be routine in research laboratories and clinical settings. Because the technology is becoming more affordable, genomics can and should be used proactively to build our preparedness and responsiveness to biological threats. All pieces, including major continued funding, advances in next-generation sequencing technologies, bioinformatics infrastructures, and open access to data and metadata, are being set in place for genomics to play a central role in our public health system.

  19. The role of genomics in the identification, prediction, and prevention of biological threats.

    Directory of Open Access Journals (Sweden)

    W Florian Fricke

    2009-10-01

    Full Text Available In all likelihood, it is only a matter of time before our public health system will face a major biological threat, whether intentionally dispersed or originating from a known or newly emerging infectious disease. It is necessary not only to increase our reactive "biodefense," but also to be proactive and increase our preparedness. To achieve this goal, it is essential that the scientific and public health communities fully embrace the genomic revolution, and that novel bioinformatic and computing tools necessary to make great strides in our understanding of these novel and emerging threats be developed. Genomics has graduated from a specialized field of science to a research tool that soon will be routine in research laboratories and clinical settings. Because the technology is becoming more affordable, genomics can and should be used proactively to build our preparedness and responsiveness to biological threats. All pieces, including major continued funding, advances in next-generation sequencing technologies, bioinformatics infrastructures, and open access to data and metadata, are being set in place for genomics to play a central role in our public health system.

  20. Central line infections - hospitals

    Science.gov (United States)

    ... infection; Central venous catheter - infection; CVC - infection; Central venous device - infection; Infection control - central line infection; Nosocomial infection - central line infection; Hospital acquired ...

  1. Radiation, multiple dispersal and parallelism in the skinks, Chalcides and Sphenops (Squamata: Scincidae), with comments on Scincus and Scincopus and the age of the Sahara Desert.

    Science.gov (United States)

    Carranza, S; Arnold, E N; Geniez, Ph; Roca, J; Mateo, J A

    2008-03-01

    Phylogenetic analysis using up to 1325 base pairs of mitochondrial DNA from 179 specimens and 30 species of Chalcides, Sphenops, Eumeces, Scincopus and Scincus indicates that Sphenops arose twice independently within Chalcides. It is consequently synonymized with that genus. Chalcides in this broader sense originated in Morocco, diversifying into four main clades about 10 Ma, after which some of its lineages dispersed widely to cover an area 40 times as large. Two separate lineages invaded the Canary Islands and at least five main lineages colonized southern Europe. At least five more spread across northern Africa, one extending into southwest Asia. Elongate bodies with reduced limbs have evolved at least four times in Chalcides, mesic 'grass-swimmers' being produced in one case and extensive adaptation to life in loose desert sand in two others. In clade, Chalcides striatus colonized SW Europe from NW Africa 2.6 Ma and C. chalcides mainland Italy 1.4 Ma, both invasions being across water, while C. c. vittatus reached Sardinia more recently, perhaps anthropogenically, and C. guentheri spread 1200km further east to Israel. C. minutus is a composite, with individuals from the type locality forming a long independent lineage and the remaining ones investigated being most closely related to C. mertensi. In the Northern clade, C. boulengeri and C. sepsoides spread east through sandy habitats north of the Sahara about 5 Ma, the latter reaching Egypt. C. bedriagai invaded Spain around the same time, perhaps during the Messinian period when the Mediterranean was dry, and shows considerable diversification. Although it is currently recognized as one species, the C. ocellatus clade exhibits as much phylogenetic depth as the other main clades of Chalcides, having at least six main lineages. These have independently invaded Malta and Sardinia from Tunisia and also southwest Arabia C. o. humilis appears to have spread over 4000 km through the Sahel, south of the Sahara quite

  2. Physicochemical and microbiological study of “shmen”, a traditional butter made from camel milk in the Sahara (Algeria: isolation and identification of lactic acid bacteria and yeasts

    Directory of Open Access Journals (Sweden)

    Mourad, Kacem

    2006-06-01

    Full Text Available Microorganisms (aerobic bacteria, coliforms, lactic acid bacteria, psychrotrophs, lipolytic bacteria and yeasts were isolated from 20 samples of shmen, a traditional clarified butter made from sour camel milk in the Algerian Sahara. The values of pH, titratable acidity, NaCl, total solid, moisture, and fat content ranged from : 3.11-4.97, 0.19-0.36%, 1.04-2.15%, 64.03-65.11%, 34.40-34.99%, and 49.90-56% respectively. A total of 181 isolates of lactic acid bacteria were identified as Lactobacillus plantarum (40 strains, Lactobacillus delbrueckii ssp. bulgaricus (35 strains, Lactococcus lactis ssp. lactis biovar diacetylacti (22 strains, Lactococcus lactis ssp. cremoris (18 strains, Lactobacillus paracasei ssp. paracasei (10 strains, Leuconostoc pseudomesenteroides (9 strains and Leuconostoc gelidum (12 strains Enterococcus faecium (35 strains. Yeasts were isolated from all samples (55 isolates. Of these, 40 were identified as Saccharomyces cerevisiae and 15 isolates were identified as Saccharomyces sp.Se aislaron los microorganismos (bacterias aeróbicas, coliformes, bacterias acido lácticas, bacterias lipolíticas y levaduras de 20 muestras de “shmen”, una matequilla tradicional del Sahara argelino hecha a partir de leche de camella. Los valores de pH, acidez, libre, Nacl, solidos totales, humedad y grasa oscilaron entre 3,11-4,97, 0,19-0,36%, 1.04-2,15%, 64,03-65,11%, 34,40-34,99% y 49,90-56,00%, respectivamente. Entre los 181 cultivos puros de bacterias lácticas se identificaron Lactobacillus plantarum (40 cepas, Lactobacillus delbrueckii ssp. bulgaricus (35 cepas, Lactococcus lactis ssp. lactis biovar diacetylacti (22 cepas, Lactococcus lactis ssp. cremoris (18 cepas, Lactobacillus paracasei ssp. paracasei (10 cepas, Leuconostoc pseudomesenteroides (9 cepas and Leuconostoc gelidum (12cepas Enterococcus faecium (35 cepas. Asimismo, se detectaron levaduras en todas las muestras (55 cultivos puros. De estos, 40 se identificaron como

  3. World wide web: opportunities, challenges, and threats.

    Science.gov (United States)

    Edworthy, S M

    1999-01-01

    The Internet provides new opportunities to gather information on the population and may provide alternatives to the traditional methods of conducting clinical trials in systemic lupus erythematosus. The 'world wide web-www' has grown extensively in the past decade and it is estimated that there will be over 1 billion individuals on the net by the year 2005. Notifying, recruiting and assessing patients using Internet technology are already potential uses of this electronic medium. However, total reliance on the Internet could lead to biased sampling of patients with lupus. Women with low incomes or who are unemployed are less likely to have access to the Internet. Individuals with neurological deficits may have trouble using the Internet effectively. Data collected on the web may not have high reliability and much work needs to be completed to determine the psychometric properties of information derived from this source. One of the greatest threats to contend with is protecting the confidentiality of patient information when using electronic communication. Safeguards against inadvertent or unintended release of information must receive high priority in any attempt to use the Internet for clinical trials. Particular attention should be paid to email messages, which have the potential to be intercepted or sent to individuals without clearance to see patient information. Nevertheless, the costs to systems performance caused by security measures must also be considered and balanced against the need for access by those with appropriate authority. A number of websites already exist for the benefit of patients and providers. Clinicians and scientists interested in the field of lupus research will need to keep up to date on the rapidly proliferating information that is becoming available. This article lists sites which can be visited now.

  4. Pulicat Lake: A Fragile Ecosystem Under Threat

    Directory of Open Access Journals (Sweden)

    Saraswathy R.

    2016-09-01

    Full Text Available The Pulicat Lake is the second largest brackish water lake after Chilika Lake in India. The average area of the water spread is 461 sq km. During the monsoon Pulicat Lake receives freshwater through three major rivers, namely, the Swarnamukhi, the Kalangi and the Arani. The Pulicat lagoon system, which is a storehouse of rich biological resources, is under great threat because of the anthropogenic influences. The Pulicat Lake ecosystem is degraded by siltation, bar mouth dynamics, shell mining and processing and population pressure due to the resettlement of villagers from Sriharikota Island. It has been determined that the extent of the lake, including its water spread area, is decreasing. Therefore, it is essential to assess the land use / land cover changes taking place in and around Pulicat Lake using remote sensing and GIS. Studies on its sediment characteristics are also vital. The grain size content reveals that most of the sediments contain clay and silt in enormous amounts. This lake has been the prime source of a livelihood through fishing for a large section of the population living in the surrounding villages. It is the most important refuge for water birds in south India. The fishing community who lives in and around Pulicat Lake follows the Padu system for fishing in the lake. In this study, apart from studies on configuration changes and sediment analysis, a study of the flora and fauna of the lake and the socio-economic conditions of the local community were also carried out. Finally, mitigation measures for the sustainable protection of the lake’s ecosystem were identified.

  5. Pulicat Lake: A Fragile Ecosystem Under Threat

    Science.gov (United States)

    Saraswathy, R.; Pandian, Pitchai Kasinatha

    2016-09-01

    The Pulicat Lake is the second largest brackish water lake after Chilika Lake in India. The average area of the water spread is 461 sq km. During the monsoon Pulicat Lake receives freshwater through three major rivers, namely, the Swarnamukhi, the Kalangi and the Arani. The Pulicat lagoon system, which is a storehouse of rich biological resources, is under great threat because of the anthropogenic influences. The Pulicat Lake ecosystem is degraded by siltation, bar mouth dynamics, shell mining and processing and population pressure due to the resettlement of villagers from Sriharikota Island. It has been determined that the extent of the lake, including its water spread area, is decreasing. Therefore, it is essential to assess the land use / land cover changes taking place in and around Pulicat Lake using remote sensing and GIS. Studies on its sediment characteristics are also vital. The grain size content reveals that most of the sediments contain clay and silt in enormous amounts. This lake has been the prime source of a livelihood through fishing for a large section of the population living in the surrounding villages. It is the most important refuge for water birds in south India. The fishing community who lives in and around Pulicat Lake follows the Padu system for fishing in the lake. In this study, apart from studies on configuration changes and sediment analysis, a study of the flora and fauna of the lake and the socio-economic conditions of the local community were also carried out. Finally, mitigation measures for the sustainable protection of the lake's ecosystem were identified.

  6. Garlic: nature's protection against physiological threats.

    Science.gov (United States)

    Butt, Masood Sadiq; Sultan, Muhammad Tauseef; Butt, Mehmood S; Iqbal, Javaid

    2009-06-01

    Currently reliance on natural products is gaining popularity to combat various physiological threats including oxidative stress, cardiovascular complexities, cancer insurgence, and immune dysfunction. The use of traditional remedies may encounter more frequently due to an array of scientific evidence in their favor. Garlic (Allium sativum) holds a unique position in history and was recognized for its therapeutic potential. Recent advancements in the field of immunonutrition, physiology, and pharmacology further explored its importance as a functional food against various pathologies. Extensive research work has been carried out on the health promoting properties of garlic, often referred to its sulfur containing metabolites i.e. allicin and its derivatives. Garlic in its preparations are effective against health risks and even used as dietary supplements such as age garlic extract (AGE) and garlic oil etc. Its components/formulations can scavenge free radicals and protect membranes from damage and maintains cell integrity. It also provides cardiovascular protection mediated by lowering of cholesterol, blood pressure, anti-platelet activities, and thromboxane formation thus providing protection against atherosclerosis and associated disorders. Besides this, it possesses antimutagenic and antiproliferative properties that are interesting in chemopreventive interventions. Several mechanisms have been reviewed in this context like activation of detoxification phase-I and II enzymes, reactive oxygen species (ROS) generation, and reducing DNA damage etc. Garlic could be useful in preventing the suppression of immune response associated with increased risk of malignancy as it stimulates the proliferation of lymphocytes, macrophage phagocytosis, stimulates the release of interleukin-2, tumor necrosis factor-alpha and interferon-gamma, and enhances natural killer cells. In this paper much emphasis has been placed on garlic's ability to ameliorate oxidative stress, core role

  7. Gender, threat/control-override delusions and violence.

    Science.gov (United States)

    Teasdale, Brent; Silver, Eric; Monahan, John

    2006-12-01

    This study brings together the threat/control-override perspective and the literature on gender and stress coping to argue that gender moderates the association between threat delusions and violence. We suggest that men are more likely than women to respond to stressors such as threat delusions with violence. We test these ideas using data from the MacArthur Violence Risk Assessment Study, a multi-wave study of post-discharge psychiatric patients. Within-person results from two-level hierarchical models support the idea that men and women cope with threat delusions differently. Specifically, we find that men are significantly more likely to engage in violence during periods when they experience threat delusions, compared with periods when they do not experience threat delusions. In contrast, women are significantly less likely to engage in violence during times when they experience threat delusions, compared with periods when they do not. We discuss these findings in light of the literature on gender and stress coping.

  8. Information fusion: telling the story (or threat narrative)

    Science.gov (United States)

    Fenstermacher, Laurie

    2014-06-01

    Today's operators face a "double whammy" - the need to process increasing amounts of information, including "Twitter-INT"1 (social information such as Facebook, You-Tube videos, blogs, Twitter) as well as the need to discern threat signatures in new security environments, including those in which the airspace is contested. To do this will require the Air Force to "fuse and leverage its vast capabilities in new ways."2 For starters, the integration of quantitative and qualitative information must be done in a way that preserves important contextual information since the goal increasingly is to identify and mitigate violence before it occurs. To do so requires a more nuanced understanding of the environment being sensed, including the human environment, ideally from the "emic" perspective; that is, from the perspective of that individual or group. This requires not only data and information that informs the understanding of how the individuals and/or groups see themselves and others (social identity) but also information on how that identity filters information in their environment which, in turn, shapes their behaviors.3 The goal is to piece together the individual and/or collective narratives regarding threat, the threat narrative, from various sources of information. Is there a threat? If so, what is it? What is motivating the threat? What is the intent of those who pose the threat and what are their capabilities and their vulnerabilities?4 This paper will describe preliminary investigations regarding the application of prototype hybrid information fusion method based on the threat narrative framework.

  9. Prefrontal inhibition of threat processing protects working memory from interference.

    Directory of Open Access Journals (Sweden)

    Robert James Clarke

    2013-05-01

    Full Text Available Bottom-up processes can interrupt ongoing cognitive processing in order to adaptively respond to emotional stimuli of high potential significance, such as those that threaten wellbeing. However it is vital that this interference can be modulated in certain contexts to focus on current tasks. Deficits in the ability to maintain the appropriate balance between cognitive and emotional demands can severely impact on day-to-day activities. This fMRI study examined this interaction between threat processing and cognition; 18 adult participants performed a visuospatial working memory (WM task with two load conditions, in the presence and absence of anxiety induction by threat of electric shock. Threat of shock interfered with performance in the low cognitive load condition; however interference was eradicated under high load, consistent with engagement of emotion regulation mechanisms. Under low load the amygdala showed significant activation to threat of shock that was modulated by high cognitive load. A directed top-down control contrast identified two regions associated with top-down control; ventrolateral PFC and dorsal ACC. Dynamic causal modelling provided further evidence that under high cognitive load, top-down inhibition is exerted on the amygdala and its outputs to prefrontal regions. Additionally, we hypothesised that individual differences in a separate, non-emotional top-down control task would predict the recruitment of dorsal ACC and ventrolateral PFC during top-down control of threat. Consistent with this, performance on a separate dichotic listening task predicted dorsal ACC and ventrolateral PFC activation during high WM load under threat of shock, though activation in these regions did not directly correlate with WM performance. Together, the findings suggest that under high cognitive load and threat, top-down control is exerted by dACC and vlPFC to inhibit threat processing, thus enabling WM performance without threat

  10. Central Solenoid

    CERN Multimedia

    2002-01-01

    The Central Solenoid (CS) is a single layer coil wound internally in a supporting cylinder housed in the cryostat of the Liquid Argon Calorimeter. It was successfully tested at Toshiba in December 2000 and was delivered to CERN in September 2001 ready for integration in the LAr Calorimeter in 2003. An intermediate test of the chimney and proximity cryogenics was successfully performed in June 2002.

  11. Assessing Database and Network Threats in Traditional and Cloud Computing

    Directory of Open Access Journals (Sweden)

    Katerina Lourida

    2015-05-01

    Full Text Available Cloud Computing is currently one of the most widely-spoken terms in IT. While it offers a range of technological and financial benefits, its wide acceptance by organizations is not yet wide spread. Security concerns are a main reason for this and this paper studies the data and network threats posed in both traditional and cloud paradigms in an effort to assert in which areas cloud computing addresses security issues and where it does introduce new ones. This evaluation is based on Microsoft’s STRIDE threat model and discusses the stakeholders, the impact and recommendations for tackling each threat.

  12. A Probabilistic Analysis Framework for Malicious Insider Threats

    DEFF Research Database (Denmark)

    Chen, Taolue; Kammuller, Florian; Nemli, Ibrahim

    2015-01-01

    threats, based on probabilistic modelling, verification, and synthesis techniques. The framework first identifies insiders’ intention to perform an inside attack, using Bayesian networks, and in a second phase computes the probability of success for an inside attack by this actor, using probabilistic......Malicious insider threats are difficult to detect and to mitigate. Many approaches for explaining behaviour exist, but there is little work to relate them to formal approaches to insider threat detection. In this work we present a general formal framework to perform analysis for malicious insider...

  13. Europa central

    Directory of Open Access Journals (Sweden)

    Karel BARTOSEK

    2010-02-01

    Full Text Available La investigación francesa continúa interesándose por Europa Central. Desde luego, hay límites a este interés en el ambiente general de mi nueva patria: en la ignorancia, producto del largo desinterés de Francia por este espacio después de la Segunda Guerra Mundial, y en el comportamiento y la reflexión de la clase política y de los medios de comunicación (una anécdota para ilustrar este ambiente: durante la preparación de nuestro coloquio «Refugiados e inmigrantes de Europa Central en el movimiento antifascista y la Resistencia en Francia, 1933-1945», celebrado en París en octubre de 1986, el problema de la definición fue planteado concreta y «prácticamente». ¡Y hubo entonces un historiador eminente, para quién Alemania no formaría parte de Europa Central!.

  14. CRISIS FOCUS: Bubbles Pose The Biggest Threat

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The shift of China’s monetary policy stance from "moderately loose" to "prudent" next year indicates curbing inflation and asset bubbles have become the Central Government’s top priority. But is China’s bubble problem short-term or long-term? Is it only monetary or related to economic structure? Is it the cause of China’s economic imbalance or the result? And what kind of deep-rooted problems in the macro economy does it reflect? All these questions call for deep thought, said Zhang Monan, a researcher with the State Information Center, in a recent article for The Beijing News. Edited excerpt follows:

  15. Fluctuations in [¹¹C]SB207145 PET binding associated with change in threat-related amygdala reactivity in humans

    DEFF Research Database (Denmark)

    Fisher, Patrick MacDonald; Haahr, Mette Ewers; Jensen, Christian Gaden

    2015-01-01

    resonance imaging while performing a gender discrimination task of fearful, angry, and neutral faces. This offered a unique opportunity to evaluate whether individual fluctuations in central serotonin levels, indexed by change in [11C]SB207145 binding, predicted changes in threat-related reactivity (ie...

  16. A Physicist Looks at the Terrorist Threat

    Science.gov (United States)

    Muller, Richard

    2009-05-01

    Many people fear a terrorist nuclear device, smuggled into the United States, as the one weapon that could surpass the destruction and impact of 9-11. I'll review the design of nuclear weapons, with emphasis on the kinds that can be developed by rogue nations, terrorist groups, and high-school students. Saddam, prior to the first gulf war, was developing a uranium bomb, similar to the one that destroyed Hiroshima. His calutrons (named after my university) were destroyed by the United Nations. The North Korean nuclear weapon was, like the U.S. bomb used on Nagasaki, based on plutonium. Its test released the energy equivalent of about 400 tons of TNT. Although some people have speculated that they were attempting to build a small bomb, it is far more likely that this weapon was a fizzle, with less than 1 percent of the plutonium exploded. In contrast, the energy released from burning jet fuel at the 9-11 World Trade Center attack was the equivalent of 900 tons of TNT for each plane -- over twice that of the North Korean Nuke. The damage came from the fact that gasoline delivers 10 kilocalories per gram, about 15 times the energy of an equal weight of TNT. It is this huge energy per gram that also accounts for our addiction to gasoline; per gram, high performance lithium-ion computer batteries carry only 1 percent as much energy. A dirty bomb (radiological weapon) is also unattractive to terrorists because of the threhold effect: doses less than 100 rem produce no radiation illness and will leave no dead bodies at the scene. That may be why al Qaeda instructed Jose Padilla to abandon his plans for a dirty bomb attack in Chicago, and to try a fossil fuel attack (natural gas) instead. I will argue that the biggest terrorist threat is the conventional low-tech one, such as an airplane attack on a crowded stadium using the explosive fuel that they can legally buy at the corner station.

  17. Threats to China's Biodiversity by Contradictions Policy.

    Science.gov (United States)

    Zheng, Heran; Cao, Shixiong

    2015-02-01

    China has among the highest biodiversities in the world, but faces extreme biodiversity losses due to the country's huge population and its recent explosive socioeconomic development. Despite huge efforts and investments by the government and Chinese society to conserve biodiversity, especially in recent decades, biodiversity losses may not have been reversed, and may even have been exacerbated by unintended consequences resulting from these projects. China's centralized approach to biodiversity conservation, with limited local participation, creates an inflexible and inefficient approach because of conflicts between local communities and national administrators over the benefits. Although community-based conservation may be an imperfect approach, it is an essential component of a successful future national conservation plan. Biodiversity conservation should be considered from the perspective of systems engineering and a governance structure that combines centralization with community-level conservation. In this paper, we describe China's complex challenge: how to manage interactions between humans and nature to find win-win solutions that can ensure long-term biodiversity conservation without sacrificing human concerns.

  18. Le développement humain local dans les contextes de crise permanente : l’expérience des femmes au Sahara Occidental

    Directory of Open Access Journals (Sweden)

    María López Belloso

    2009-04-01

    Full Text Available Les femmes sahraouies sont des agents actifs dans la dynamique sociale des camps de réfugiés, au sein desquels elles ont défini un certain nombre de stratégies de résolution de problèmes pour surmonter les obstacles liés à une situation humanitaire qui se détériore. Depuis le début du conflit et le déplacement forcé à Tindouf, en Algérie, les femmes sont en e%et intégralement responsables de la gestion des camps de réfugiés, et ont assumé un rôle de dirigeantes dans de nombreux secteurs de la société. Cet article souligne la contribution des femmes sahraouies au processus de développement humain local dans un contexte de refuge prolongé tel celui que connaît le Sahara Occidental. En plus d’améliorer la capacité d’accès des réfugiés aux ressources matérielles, physiques, sociales et organisationnelles ainsi qu’aux forces motivationnelles, les femmes sahraouies ont été en mesure de mettre en place leur propre processus de renforcement des capacitésII individuelle et collective dans la vie du camp.

  19. New early Pliocene owls from Langebaanweg, South Africa, with first evidence of Athene south of the Sahara and a new species of Tyto

    Directory of Open Access Journals (Sweden)

    Marco Pavia

    2015-12-01

    Full Text Available The fossiliferous Upper Varswater Formation at Langebaanweg (South Africa produced remains of at least five species of owls (Strigiformes. Tyto richae sp. nov. is the first palaeospecies of Tytonidae described from an African fossil site, though indeterminate remains referable to the genus Tyto are known from the Middle Miocene of Morocco, the early Pliocene of Ethiopia, and the Pliocene of Tanzania. Athene inexpectata sp. nov. is not only the earliest documented fossil evidence for the genus worldwide, but also the first record of a species of Athene in Africa south of the Sahara. Proportions of its hind limb indicate that At. inexpectata sp. nov. probably has been as terrestrial as its modern relative At. cunicularia. A few additional remains represent the earliest fossil evidence for the genera Asio and Bubo on the African continent, though the poor preservation of these bones prevents more detailed identifications. A distal tibiotarsus of a small owl about the size of At. inexpectata sp. nov. indicates the presence of a fifth, as yet indeterminate, species of owl at Langebaanweg. Biogeographical and palaeoecological implications of this assemblage of owls are discussed.

  20. Desert Dust Air Mass Mapping in the Western Sahara, using Particle Properties Derived from Space-based Multi-angle Imaging

    Science.gov (United States)

    Kahn, Ralph; Petzold, Andreas; Wendisch, Manfred; Bierwirth, Eike; Dinter, Tilman; Fiebig, Marcus; Schladitz, Alexander; von Hoyningen-Huene, Wolfgang

    2008-01-01

    Coincident observations made over the Moroccan desert during the SAhara Mineral dUst experiMent (SAMUM) 2006 field campaign are used both to validate aerosol amount and type retrieved from Multi-angle Imaging SpectroRadiometer (MISR) observations, and to place the sub-orbital aerosol measurements into the satellite's larger regional context. On three moderately dusty days for which coincident observations were made, MISR mid-visible aerosol optical thickness (AOT) agrees with field measurements point-by-point to within 0.05 to 0.1. This is about as well as can be expected given spatial sampling differences; the space-based observations capture AOT trends and variability over an extended region. The field data also validate MISR's ability to distinguish and to map aerosol air masses, from the combination of retrieved constraints on particle size, shape, and single-scattering albedo. For the three study days, the satellite observations (a) highlight regional gradients in the mix of dust and background spherical particles, (b) identify a dust plume most likely part of a density flow, and (c) show an air mass containing a higher proportion of small, spherical particles than the surroundings, that appears to be aerosol pollution transported from several thousand kilometers away.

  1. Desert Dust Aerosol Air Mass Mapping in the Western Sahara, Using Particle Properties Derived from Space-Based Multi-Angle Imaging

    Science.gov (United States)

    Kahn, Ralph; Petzold, Andreas; Wendisch, Manfred; Bierwirth, Eike; Dinter, Tilman; Esselborn, Michael; Fiebig, Marcus; Heese, Birgit; Knippertz, Peter; Mueller, Detlef; Schladitz, Alexander; Von Hoyningen-Huene, Wolfgang

    2008-01-01

    Coincident observations made over the Moroccan desert during the Sahara mineral dust experiment (SAMUM) 2006 field campaign are used both to validate aerosol amount and type retrieved from multi-angle imaging spectroradiometer (MISR) observations, and to place the suborbital aerosol measurements into the satellite s larger regional context. On three moderately dusty days during which coincident observations were made, MISR mid-visible aerosol optical thickness (AOT) agrees with field measurements point-by-point to within 0.05 0.1. This is about as well as can be expected given spatial sampling differences; the space-based observations capture AOT trends and variability over an extended region. The field data also validate MISR s ability to distinguish and to map aerosol air masses, from the combination of retrieved constraints on particle size, shape and single-scattering albedo. For the three study days, the satellite observations (1) highlight regional gradients in the mix of dust and background spherical particles, (2) identify a dust plume most likely part of a density flow and (3) show an aerosol air mass containing a higher proportion of small, spherical particles than the surroundings, that appears to be aerosol pollution transported from several thousand kilometres away.

  2. Biocontrol of Rhizoctonia solani damping-off and promotion of tomato plant growth by endophytic actinomycetes isolated from native plants of Algerian Sahara.

    Science.gov (United States)

    Goudjal, Yacine; Toumatia, Omrane; Yekkour, Amine; Sabaou, Nasserdine; Mathieu, Florence; Zitouni, Abdelghani

    2014-01-20

    Thirty-four endophytic actinomycetes were isolated from the roots of native plants of the Algerian Sahara. Morphological and chemical studies showed that twenty-nine isolates belonged to the Streptomyces genus and five were non-Streptomyces. All isolates were screened for their in vitro antifungal activity against Rhizoctonia solani. The six that had the greatest pathogen inhibitory capacities were subsequently tested for their in vivo biocontrol potential on R. solani damping-off in sterilized and non-sterilized soils, and for their plant-growth promoting activities on tomato seedlings. In both soils, coating tomato seeds with antagonistic isolates significantly reduced (P<0.05) the severity of damping-off of tomato seedlings. Among the isolates tested, the strains CA-2 and AA-2 exhibited the same disease incidence reduction as thioperoxydicarbonic diamide, tetramethylthiram (TMTD) and no significant differences (P<0.05) were observed. Furthermore, they resulted in a significant increase in the seedling fresh weight, the seedling length and the root length of the seed-treated seedlings compared to the control. The taxonomic position based on 16S rDNA sequence analysis and phylogenetic studies indicated that the strains CA-2 and AA-2 were related to Streptomyces mutabilis NBRC 12800(T) (100% of similarity) and Streptomyces cyaneofuscatus JCM 4364(T) (100% of similarity), respectively.

  3. Surviving in mountain climate refugia: new insights from the genetic diversity and structure of the relict shrub Myrtus nivellei (Myrtaceae) in the Sahara Desert.

    Science.gov (United States)

    Migliore, Jérémy; Baumel, Alex; Juin, Marianick; Fady, Bruno; Roig, Anne; Duong, Nathalie; Médail, Frédéric

    2013-01-01

    The identification of past glacial refugia has become a key topic for conservation under environmental change, since they contribute importantly to shaping current patterns of biodiversity. However, little attention has been paid so far to interglacial refugia despite their key role for the survival of relict species currently occurring in climate refugia. Here, we focus on the genetic consequences of range contraction on the relict populations of the evergreen shrub Myrtus nivellei, endemic in the Saharan mountains since at least the end of the last Green Sahara period, around 5.5 ka B.P. Multilocus genotypes (nuclear microsatellites and AFLP) were obtained from 215 individuals collected from 23 wadis (temporary rivers) in the three main mountain ranges in southern Algeria (the Hoggar, Tassili n'Ajjer and Tassili n'Immidir ranges). Identical genotypes were found in several plants growing far apart within the same wadis, a pattern taken as evidence of clonality. Multivariate analyses and Bayesian clustering revealed that genetic diversity was mainly structured among the mountain ranges, while low isolation by distance was observed within each mountain range. The range contraction induced by the last episode of aridification has likely increased the genetic isolation of the populations of M. nivellei, without greatly affecting the genetic diversity of the species as a whole. The pattern of genetic diversity observed here suggests that high connectivity may have prevailed during humid periods, which is consistent with recent paleoenvironmental reconstructions.

  4. Determination of the specific activities of the cosmogenic nuclides {sup 10}Be and {sup 26}Al in meteorites from the Sahara by means of accelerator mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Meltzow, B. [Koeln Univ. (Germany). Abt. Nuklearchemie; Herpers, U. [Koeln Univ. (Germany). Abt. Nuklearchemie; Romstedt, J. [Muenster Univ. (Germany). Inst. fuer Planetologie; Dittrich-Hannen, B. [Eidgenoessische Technische Hochschule, Zurich (Switzerland). Inst. fuer Teilchenphysik; Kubik, P.W. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Suter, M. [Eidgenoessische Technische Hochschule, Zurich (Switzerland). Inst. fuer Teilchenphysik

    1996-06-01

    In 30 samples of meteorites from the Sahara the specific activity of {sup 26}Al, and in the case of rare meteorite types also that of {sup 10}Be was determined. In most cases, the measured data are consistent with the suggestions about possible pairings which were based on mineralogical and petrographical investigations. The investigated CR and CH chondrites were found to be saturated in {sup 26}Al and {sup 10}Be. The {sup 26}Al and {sup 10}Be production rates can be assumed to be (44.5{+-}0.9) dpm/kg and (20.7{+-}0.3) dpm/kg, respectively, for CR as well as (30.1{+-}0.9) dpm/kg and (16.7{+-}0.4) dpm/kg for CH chondrites. Furthermore the {sup 26}Al data of 11 ordinary chondrites can also be interpreted as saturation activities and allow the assumption of 3.10{sup 6} y to be the lower limit of the exposure ages of these meteorites. In the case of Acfer 277, in addition to the {sup 10}Be and {sup 26}Al determinations, a study on nuclear tracks was performed. These data suggest that the investigated sample was located at no more than 8 cm below the original surface of a meteoroid of a radius between 25 cm and 65 cm which traveled through space (0.3{+-}0.1).10{sup 6} y before entering the earth`s atmosphere. (orig.)

  5. Assessment of Containment Structures Against Missile Impact Threats

    Institute of Scientific and Technical Information of China (English)

    LI Q M

    2006-01-01

    In order to ensure the highest safety requirements,nuclear power plant structures (the containment structures,the fuel storages and transportation systems) should be assessed against all possible internal and external impact threats.The internal impact threats include kinetic missiles generated by the failure of high pressure vessels and pipes,the failure of high speed rotating machineries and accidental drops.The external impact threats may come from airborne missiles,aircraft impact,explosion blast and fragments.The impact effects of these threats on concrete and steel structures in a nuclear power plant are discussed.Methods and procedures for the impact assessment of nuclear power plants are introduced.Recent studies on penetration and perforation mechanics as well as progresses on dynamic properties of concrete-like materials are presented to increase the understanding of the impact effects on concrete containment structures.

  6. Reassessing biological threats: Implications for cooperative mitigation strategies

    Directory of Open Access Journals (Sweden)

    Catharine Grace Young

    2015-11-01

    Full Text Available Multiple factors ranging from globalization to ecosystem disruption are presenting the global community with evolving biological threats to local, national, and global security that reach beyond the realm of traditional bioweapons threats. As a result, mitigation strategies have adapted necessarily to the increased diversity of biological threats. In general, response and preparedness strategies have largely shifted from being primarily reactive to traditional biological weapons to more proactive in nature. In this review, we briefly explore biological threats through a wider aperture, to embrace a deeper appreciation of viral pathogens, antimicrobial resistance, and agricultural pathogens, and their potential to cause civil, economic, and political devastation. In addition we discuss current mitigation strategies codified by the Global Health Security Agenda and the One Health paradigm, as well as some of the available tools to assist with their sustainable implementation.

  7. Little Threat of Zika Spread from Rio Olympics

    Science.gov (United States)

    ... html Little Threat of Zika Spread From Rio Olympics: Study Because it's winter in Brazil, mosquito activity ... HealthDay News) -- Travelers and competitors at the 2016 Olympic Games in Brazil are not likely to contract ...

  8. Antibiotic Resistance Threats in the U.S.

    Science.gov (United States)

    ... What's this? Submit Button Past Emails CDC Features Antibiotic Resistance Threats in the US Recommend on Facebook Tweet Share Compartir Antibiotics are powerful tools for fighting illness and disease, ...

  9. Solutions to the new threats to academic freedom?

    Science.gov (United States)

    Tooley, Michael

    2014-05-01

    In my commentary on Francesca Minerva's article 'New Threats to Academic Freedom', I agree with her contention that the existence of the Internet has given rise to new and very serious threats to academic freedom. I think that it is crucial that we confront those threats, and find ways to eliminate them, which I believe can be done. The threats in question involve both authors and editors. In the case of authors, I argue that the best solution is not anonymous publication, but publication using pseudonyms, and I describe how that would work. In the case of editors, my proposal is a website that a number of journals would have access to, where papers that editors judge to be clearly worthy of publication, but whose publication seems likely to set off a firestorm of public and media protest, could be published without any indication of the journal that had accepted the paper for publication.

  10. Stereotype threat and arousal: effects on women's math performance.

    Science.gov (United States)

    O'Brien, Laurie T; Crandall, Christian S

    2003-06-01

    Theories of arousal suggest that arousal should decrease performance on difficult tasks and increase performance on easy tasks. An experiment tested the hypothesis that the effects of stereotype threat on performance are due to heightened arousal. The authors hypothesized that telling participants that a math test they are about to take is known to have gender differences would cause stereotype threat in women but not in men. In the experiment, each participant took two tests--a difficult math test and an easy math test. Compared to women in a "no differences" condition, women in the "gender differences" condition scored better on the easy math test and worse on the difficult math test. Men's performance was unaffected by the manipulation. These data are consistent with an arousal-based explanation of stereotype threat effects. Data were inconsistent with expectancy, evaluation apprehension, and persistence explanations of the stereotype threat phenomenon.

  11. Puerto Rico Land-Based Threat to Benthic Habitats

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set describes the potential threat of sediment delivery and land-based sources of pollution to benthic habitats. This dataset is derived from NOAA's...

  12. Perceived threats of individuals recovering from myocardial infarction.

    Science.gov (United States)

    Bennett, S J

    1992-01-01

    Lazarus' phenomenological theory of stress and coping provided the basis for this descriptive study of perceived threats after myocardial infarction (MI). Sixty-four post-MI subjects enrolled in phase II cardiac rehabilitation programs identified threats they had experienced in the past month. Perceived threats were defined as situations that were difficult or troubling to the individual and were described by respondents in narrative form. Degree of threat was then measured by one item on which subjects indicated the degree of concern the threatening event had caused them. Responses to the one item were analyzed and categorized into the following five areas: physical problems; medical therapy/self-care; work/physical activity; interpersonal/family; and financial. The results provide an overview of the multiple concerns individuals deal with after a major life-threatening cardiac event.

  13. New Frontiers of Network Security: The Threat Within

    CERN Document Server

    Sanyal, Sugata; Gupta, Amit

    2010-01-01

    Nearly 70% of information security threats originate from inside an organization. Opportunities for insider threats have been increasing at an alarming rate with the latest trends of mobility (portable devices like Laptop, smart phones etc.), ubiquitous connectivity (wireless or through 3G connectivity) and this trend increases as more and more web-based applications are made available over the Internet. Insider threats are generally caused by current or ex-employees, contractors or partners, who have authorized access to the organization's network and servers. Theft of confidential information is often for either material gain or for willful damage. Easy availability of hacking tools on the Internet, USB devices and wireless connectivity provide for easy break-ins. The net result is losses worth millions of dollars in terms of IP theft, leakage of customer / individual information, etc. This paper presents an understanding of Insider threats, attackers and their motives and suggests mitigation techniques at ...

  14. A developmental perspective on the Virginia Student Threat Assessment Guidelines.

    Science.gov (United States)

    Cornell, Dewey G

    2011-01-01

    The Virginia Student Threat Assessment Guidelines were developed to help multidisciplinary school-based teams use a decision tree to evaluate student threats and take appropriate preventive action. A main goal of this approach is to allow school-based teams to recognize and respond to the developmental complexities of children and adolescents without resorting to the use of zero tolerance discipline. The model takes a triage approach that involves progressively more extensive assessment and intervention according to the severity of the threat and the student's intentions. The article summarizes two field test studies of the model, a study of training effects on staff attitudes and knowledge about violence prevention, and a quasi-experimental study showing that secondary schools using the model enjoyed a more positive school climate characterized by less bullying and greater willingness among students to seek help for threats of violence.

  15. Stereotype threat and hazard perception among provisional license drivers.

    Science.gov (United States)

    Skorich, Daniel P; Webb, Hugh; Stewart, Lisa; Kostyanaya, Maria; Cruwys, Tegan; McNeill, Kathy; Frain, Andrew J; Lim, Li; Jones, Benjamin M; Smyth, Lillian; O'Brien, Kerry J

    2013-05-01

    Stereotype threat refers to the negative impact a stereotype about one's group can have on one's performance in domains relevant to the stereotype. In the current paper, we explore whether the negative stereotype of provisional license drivers (PLDs) might produce stereotype threat in a driving-related hazard perception task. We manipulate threat by asking participants to self-identify as PLDs in a categorization condition, or by reminding PLD participants explicitly of the stereotype of PLDs in an explicit stereotype condition. Results reveal increments in hazard perception in the categorization condition, and decrements in hazard perception in the explicit stereotype condition. Mediation analysis reveals that hazard perception performance is fully mediated by increased effort in the categorization condition and by decreased effort in the explicit stereotype condition. We discuss these findings in terms of their implications for stereotype threat and its mediators, and for public policy that explicitly discriminates between PLDs and other driver groups.

  16. Racial Threat Theory: Assessing the Evidence, Requesting Redesign

    Directory of Open Access Journals (Sweden)

    Cindy Brooks Dollar

    2014-01-01

    Full Text Available Racial threat theory was developed as a way to explain how population composition influences discriminatory social control practices and has become one of the most acknowledged frameworks for explaining racial disparity in criminal justice outcomes. This paper provides a thorough review of racial threat theory and empirical assessments of the theory and demonstrates that while scholars often cite inconsistent support for the theory, empirical discrepancies may be due to insufficient attention to the conceptual complexity of racial threat. I organize and present the following review around 4 forms of state-sanctioned control mechanisms: police expenditures, arrests, sentencing, and capital punishment. Arguing that the pervasiveness of racialization in state controls warrants continued inquiry, I provide suggestions for future scholarship that will help us develop enhanced understanding of how racial threat may be operating.

  17. Threats and Dangers in Activity of the Tourism Sector Enterprises

    Directory of Open Access Journals (Sweden)

    Markina Iryna А.

    2015-03-01

    Full Text Available The aim of the article is to investigate the threats and dangers that affect not only the management system of the tourism sector enterprises, but their safety as well. By analyzing, systematizing and summarizing the scientific works of many scientists, the essence of the concepts of “danger” and “threat” has been considered, and the classification of dangers and threats faced by tourism enterprises in an unstable environment has been carried out. As a result of the research there have been identified the main threats and dangers peculiar for subjects of tourist activity that occur in the process of operation of tourism enterprises and deficiencies in the management of material, information, human, financial and other resources of tourism enterprises. The main prospect for further research in this area is to identify the potential directions for minimizing the risks and threats that ensure not only the appropriate level of the tourism enterprise competitiveness, but its development as well.

  18. Puerto Rico Land-Based Threat to Benthic Habitats

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set describes the potential threat of sediment delivery and land-based sources of pollution to benthic habitats. This dataset is derived from NOAA's study,...

  19. Fundamentalism and postmodernism: two threats to interreligious dialogue

    NARCIS (Netherlands)

    Poorthuis, Marcel

    2015-01-01

    Due to anti-institutional bias and a tendency to individualism, interreligious dialogue seems to decline in Western Europe. Two seemingly contradictory currents, fundamentalism and postmodernism constoitute in reality similar threats to interreligious dialogue

  20. Threat, prejudice and the impact of the riots in England.

    Science.gov (United States)

    de Rooij, Eline A; Goodwin, Matthew J; Pickup, Mark

    2015-05-01

    This paper examines how a major outbreak of rioting in England in 2011 impacted on prejudice toward three minority groups in Britain: Muslims, Black British and East Europeans. We test whether the riots mobilized individuals by increasing feelings of realistic and symbolic threat and ultimately prejudice, or whether the riots galvanized those already concerned about minorities, thus strengthening the relationship between threat and prejudice. We conducted three national surveys - before, after and one year on from the riots - and show that after the riots individuals were more likely to perceive threats to society's security and culture, and by extension express increased prejudice toward Black British and East European minorities. We find little evidence of a galvanizing impact. One year later, threat and prejudice had returned to pre-riots levels; however, results from a survey experiment show that priming memories of the riots can raise levels of prejudice.

  1. Wireless Security Threats, Vulnerabilities and Their Defense Mechanisms

    Directory of Open Access Journals (Sweden)

    Ankur Bawiskar

    2013-01-01

    Full Text Available In today’s world means of communications has changed rapidly and the main focus is on wireless communications. Communication in wireless mode has many threats. This paper discusses a brief overview of various threats to wireless networks at various layers and also presents a survey of the defense mechanisms. The main aim is to discuss attacks on MANET and their defense mechanisms. Communication in wireless mode is more challenging as compared to wired mode because of dynamically changing network topology. Wireless networks are mostly used in military applications and commercial applications. This paper also discusses internal threats and external threats. It also gives an overview of routing protocols being used in wireless networks and various attacks that take place against these routing protocols and their counter measures.

  2. USVI Land-Based Threat to Benthic Habitats

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set describes the potential threat of sediment delivery and land-based sources of pollution to benthic habitats. This dataset is derived from NOAA's...

  3. TERRORISM AS THE MAIN THREAT TO THE STATE DEFENCE

    Directory of Open Access Journals (Sweden)

    T. V. VERBITSKAYA

    2015-01-01

    Full Text Available The article focuses on the analysis of terrorism as the main threat to the state defense. One of the main problems in combating this threat is lack of the uniformity in understanding and definition of terrorism on national and international level, what complicates the search of the means reducing this threat. In addition, because of possible use of armed forces against this threat, the absence of understanding of this term as the basis for introducing relevant legal regimes may lead to violation of human rights. The article presents definitions of terrorism from normative acts of foreign countries and sources of international law. It traces the historical development of the understanding of terrorism in different countries in terms of the evolution of the content of this term.

  4. Best Practices and Controls for Mitigating Insider Threats

    Science.gov (United States)

    2013-08-08

    for plagiarism in academic papers, the process is virtually identical Solution: Managing The Insider Threat: What Every Organization Should Know...hundreds of actual cases of insider IT sabotage, theft of intellectual property, fraud, and espionage Managing The Insider Threat: What Every...service provider that meets or exceeds the organization’s own levels of security. •  Understand how the cloud provider protect data and other assets

  5. Darknet and Deepnet Mining for Proactive Cybersecurity Threat Intelligence

    OpenAIRE

    Nunes, Eric; Diab, Ahmad; Gunn, Andrew; Marin, Ericsson; Mishra, Vineet; Paliath, Vivin; Robertson, John; Shakarian, Jana; Thart, Amanda; Shakarian, Paulo

    2016-01-01

    In this paper, we present an operational system for cyber threat intelligence gathering from various social platforms on the Internet particularly sites on the darknet and deepnet. We focus our attention to collecting information from hacker forum discussions and marketplaces offering products and services focusing on malicious hacking. We have developed an operational system for obtaining information from these sites for the purposes of identifying emerging cyber threats. Currently, this sys...

  6. Dubai and the United Arab Emirates : security threats.

    OpenAIRE

    Christopher M. Davidson

    2009-01-01

    The United Arab Emirates’ (UAE) wealthiest emirate, Abu Dhabi, has built up the UAE Armed Forces in recent decades by procuring some of the finest military hardware available. This has provided the UAE with a strong defence shield and has undoubtedly reduced the threat of foreign invasion. However, the UAE’s hard security capabilities are either insufficient or inappropriate for countering remaining regional threats from Iran or, to a lesser extent, other Arab states. As such, ...

  7. S5: New Threats to Cyber-Security

    Science.gov (United States)

    2014-10-29

    2014 Carnegie Mellon University 29-Oct-2014 S5 : New Threats to Cyber-Security Software Engineering Institute Carnegie Mellon University...unclassified Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 2 Mark Sherman S5 : New Threats to Cyber-Security © 2014 Carnegie...Institute at permission@sei.cmu.edu. Carnegie Mellon® and CERT® are registered marks of Carnegie Mellon University. DM-0001805 3 Mark Sherman S5

  8. Intergovernmental Unity of Effort in Support of Biological Threat Prevention

    Science.gov (United States)

    2013-09-01

    96  xii THIS PAGE INTENTIONALLY LEFT BLANK xiii LIST OF TABLES Table 1.  Health Security Policy Biological Threat...level. Retrieved September 18, 2012, from http://ec.europa.eu/health/ph_threats/com/preparedness/docs/HEOF_en.pdf. Europa a Constitution for Europe...home.html. Europa Summaries of EU Legislation (2008, September). The fight against bioterrorism (communication). Retrieved January 15, 2011, from

  9. Physician office readiness for managing Internet security threats.

    Science.gov (United States)

    Keshavjee, K; Pairaudeau, N; Bhanji, A

    2006-01-01

    Internet security threats are evolving toward more targeted and focused attacks.Increasingly, organized crime is involved and they are interested in identity theft. Physicians who use Internet in their practice are at risk for being invaded. We studied 16 physician practices in Southern Ontario for their readiness to manage internet security threats. Overall, physicians have an over-inflated sense of preparedness. Security practices such as maintaining a firewall and conducting regular virus checks were not consistently done.

  10. Central pain.

    Science.gov (United States)

    Singh, Supreet

    2014-12-01

    Questions from patients about pain conditions and analgesic pharmacotherapy and responses from authors are presented to help educate patients and make them more effective self-advocates. The topic addressed in this issue is central pain, a neuropathic pain syndrome caused by a lesion in the brain or spinal cord that sensitizes one's perception of pain. It is a debilitating condition caused by various diseases such as multiple sclerosis, strokes, spinal cord injuries, or brain tumors. Varied symptoms and the use of pharmacological medicines and nonpharmacological therapies will be addressed.

  11. central t

    Directory of Open Access Journals (Sweden)

    Manuel R. Piña Monarrez

    2007-01-01

    Full Text Available Dado que la Regresión Ridge (RR, es una estimación sesgada que parte de la solución de la regresión de Mínimos Cuadrados (MC, es vital establecer las condiciones para las que la distribución central t de Student que se utiliza en la prueba de hipótesis en MC, sea también aplicable a la regresión RR. La prueba de este importante resultado se presenta en este artículo.

  12. Former Military Networks a Threat to Peace? The Demobilisation and Remobilisation of Renamo in Central Mozambique

    NARCIS (Netherlands)

    Wiegink, N.

    2015-01-01

    Renamo’s recent upsurge against the Mozambican Frelimo-led government after 22 years of relative stability has challenged the country’s often celebrated disarmament, demobilization and reintegration process (1992–1994). Drawing on ethnographic fieldwork conducted in Maringue (Sofala province), the l

  13. Does stereotype threat affect women in academic medicine?

    Science.gov (United States)

    Burgess, Diana Jill; Joseph, Anne; van Ryn, Michelle; Carnes, Molly

    2012-04-01

    Multiple complex factors contribute to the slow pace of women's advancement into leadership positions in academic medicine. In this article, the authors propose that stereotype threat--under which individuals who are members of a group characterized by negative stereotypes in a particular domain perform below their actual abilities in that domain when group membership is emphasized--may play an important role in the underrepresentation of women in leadership positions in academic medicine. Research to objectively assess the impact of stereotype threat for women in academic medicine is feasible and necessary to confirm this hypothesis. Still, a number of conditions present in the academic medicine community today have been shown to trigger stereotype threat in other settings, and stereotype threat fits with existing research on gender in academic medicine. In the meantime, academic health centers should implement relatively simple measures supported by experimental evidence from other settings to reduce the risk of stereotype threat, including (1) introducing the concept of stereotype threat to the academic medicine community, (2) engaging all stakeholders, male and female, to promote identity safety by enacting and making faculty aware of policies to monitor potential instances of discrimination, and training faculty to provide performance feedback that is free of gender bias, (3) counteracting the effects of sex segregation at academic health centers by increasing exposure to successful female leaders, (4) reducing gender stereotype priming by avoiding stereotypically male criteria for promotion, grants, and awards, and (5) building leadership efficacy among female physicians and scientists.

  14. Neuroimaging the temporal dynamics of human avoidance to sustained threat.

    Science.gov (United States)

    Schlund, Michael W; Hudgins, Caleb D; Magee, Sandy; Dymond, Simon

    2013-11-15

    Many forms of human psychopathology are characterized by sustained negative emotional responses to threat and chronic behavioral avoidance, implicating avoidance as a potential transdiagnostic factor. Evidence from both nonhuman neurophysiological and human neuroimaging studies suggests a distributed frontal-limbic-striatal brain network supports avoidance. However, our understanding of the temporal dynamics of the network to sustained threat that prompts sustained avoidance is limited. To address this issue, 17 adults were given extensive training on a modified free-operant avoidance task in which button pressing avoided money loss during a sustained threat period. Subsequently, subjects underwent functional magnetic resonance imaging while completing the avoidance task. In our regions of interest, we observed phasic, rather than sustained, activation during sustained threat in dorsolateral and inferior frontal regions, anterior and dorsal cingulate, ventral striatum and regions associated with emotion, including the amygdala, insula, substantia nigra and bed nucleus of the stria terminalis complex. Moreover, trait levels of experiential avoidance were negatively correlated with insula, hippocampal and amygdala activation. These findings suggest knowledge that one can consistently avoid aversive outcomes is not associated with decreased threat-related responses and that individuals with greater experiential avoidance exhibit reduced reactivity to initial threat. Implications for understanding brain mechanisms supporting human avoidance and psychological theories of avoidance are discussed.

  15. A Bayesian belief network of threat anticipation and terrorist motivations

    Science.gov (United States)

    Olama, Mohammed M.; Allgood, Glenn O.; Davenport, Kristen M.; Schryver, Jack C.

    2010-04-01

    Recent events highlight the need for efficient tools for anticipating the threat posed by terrorists, whether individual or groups. Antiterrorism includes fostering awareness of potential threats, deterring aggressors, developing security measures, planning for future events, halting an event in process, and ultimately mitigating and managing the consequences of an event. To analyze such components, one must understand various aspects of threat elements like physical assets and their economic and social impacts. To this aim, we developed a three-layer Bayesian belief network (BBN) model that takes into consideration the relative threat of an attack against a particular asset (physical layer) as well as the individual psychology and motivations that would induce a person to either act alone or join a terrorist group and commit terrorist acts (social and economic layers). After researching the many possible motivations to become a terrorist, the main factors are compiled and sorted into categories such as initial and personal indicators, exclusion factors, and predictive behaviors. Assessing such threats requires combining information from disparate data sources most of which involve uncertainties. BBN combines these data in a coherent, analytically defensible, and understandable manner. The developed BBN model takes into consideration the likelihood and consequence of a threat in order to draw inferences about the risk of a terrorist attack so that mitigation efforts can be optimally deployed. The model is constructed using a network engineering process that treats the probability distributions of all the BBN nodes within the broader context of the system development process.

  16. A Bayesian Belief Network of Threat Anticipation and Terrorist Motivations

    Energy Technology Data Exchange (ETDEWEB)

    Olama, Mohammed M [ORNL; Allgood, Glenn O [ORNL; Davenport, Kristen M [ORNL; Schryver, Jack C [ORNL

    2010-01-01

    Recent events highlight the need for efficient tools for anticipating the threat posed by terrorists, whether individual or groups. Antiterrorism includes fostering awareness of potential threats, deterring aggressors, developing security measures, planning for future events, halting an event in process, and ultimately mitigating and managing the consequences of an event. To analyze such components, one must understand various aspects of threat elements like physical assets and their economic and social impacts. To this aim, we developed a three-layer Bayesian belief network (BBN) model that takes into consideration the relative threat of an attack against a particular asset (physical layer) as well as the individual psychology and motivations that would induce a person to either act alone or join a terrorist group and commit terrorist acts (social and economic layers). After researching the many possible motivations to become a terrorist, the main factors are compiled and sorted into categories such as initial and personal indicators, exclusion factors, and predictive behaviors. Assessing such threats requires combining information from disparate data sources most of which involve uncertainties. BBN combines these data in a coherent, analytically defensible, and understandable manner. The developed BBN model takes into consideration the likelihood and consequence of a threat in order to draw inferences about the risk of a terrorist attack so that mitigation efforts can be optimally deployed. The model is constructed using a network engineering process that treats the probability distributions of all the BBN nodes within the broader context of the system development process.

  17. Attentional bias to threat: a perceptual accuracy approach.

    Science.gov (United States)

    Van Damme, Stefaan; Crombez, Geert; Notebaert, Lies

    2008-12-01

    To investigate attentional bias to threatening information, the authors propose a new version of the spatial cueing paradigm in which the focus is on perceptual accuracy instead of response speed. In two experiments, healthy volunteers made unspeeded discriminations between three visual targets presented left or right. Each target was preceded by a visual cue (colored rectangle) at either the same (valid) or opposite (invalid) location. By means of differential classical conditioning with aversive white noise, a threat cue and a control cue were created. Analyses of error rates showed that cueing effects (lower proportion of errors in valid trials relative to invalid trials) were more pronounced in threat trials than in neutral trials. This threat-related bias was particularly because of threat cues reducing accuracy in invalid trials, indicating difficulty disengaging attention from threatening information. Engagement of attention was not affected by threat, as threat cues did not facilitate the processing of targets in valid trials. The findings are discussed in light of the strengths and limitations of spatial cueing tasks.

  18. The nuclear threat: a new start

    Science.gov (United States)

    Drell, Sidney

    2009-02-01

    President Obama has said that he intends to "make the goal of eliminating all nuclear weapons a central element in [US] nuclear policy". He faces enormous challenges in converting this aspiration into a practical reality, both at home and abroad. One reason is that the world has become accustomed to thinking of nuclear weapons the way Winston Churchill described them in 1955: "It may be that we shall by a process of sublime irony have reached a stage in this story where safety will be the sturdy child of terror, and survival the twin brother of annihilation." Over half a century later, the world has changed and the "sublime irony" is that terror and annihilation still loom over humanity, while safety and survival are still in doubt.

  19. Non fisheries threats - Risk, status and trends of non-fisheries threats in the California Current to groundfish species

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — We are calculating the risk of focal groundfish species to non-fisheries related threats (e.g. shipping activity, inorganic pollution) and comparing the relative...

  20. Interaction of threat and verbal working memory in adolescents.

    Science.gov (United States)

    Patel, Nilam; Vytal, Katherine; Pavletic, Nevia; Stoodley, Catherine; Pine, Daniel S; Grillon, Christian; Ernst, Monique

    2016-04-01

    Threat induces a state of sustained anxiety that can disrupt cognitive processing, and, reciprocally, cognitive processing can modulate an anxiety response to threat. These effects depend on the level of cognitive engagement, which itself varies as a function of task difficulty. In adults, we recently showed that induced anxiety impaired working memory accuracy at low and medium but not high load. Conversely, increasing the task load reduced the physiological correlates of anxiety (anxiety-potentiated startle). The present work examines such threat-cognition interactions as a function of age. We expected threat to more strongly impact working memory in younger individuals by virtue of putatively restricted cognitive resources and weaker emotion regulation. This was tested by examining the influence of age on the interaction of anxiety and working memory in 25 adolescents (10 to 17 years) and 25 adults (22 to 46 years). Working memory load was manipulated using a verbal n-back task. Anxiety was induced using the threat of an aversive loud scream and measured via eyeblink startle. Findings revealed that, in both age groups, accuracy was lower during threat than safe conditions at low and medium but not high load, and reaction times were faster during threat than safe conditions at high load but did not differ at other loads. Additionally, anxiety-potentiated startle was greater during low and medium than high load. Thus, the interactions of anxiety with working memory appear similar in adolescents and adults. Whether these similarities reflect common neural mechanisms would need to be assessed using functional neuroimaging.

  1. Effects of threat management interactions on conservation priorities.

    Science.gov (United States)

    Auerbach, Nancy A; Wilson, Kerrie A; Tulloch, Ayesha I T; Rhodes, Jonathan R; Hanson, Jeffrey O; Possingham, Hugh P

    2015-12-01

    Decisions need to be made about which biodiversity management actions are undertaken to mitigate threats and about where these actions are implemented. However, management actions can interact; that is, the cost, benefit, and feasibility of one action can change when another action is undertaken. There is little guidance on how to explicitly and efficiently prioritize management for multiple threats, including deciding where to act. Integrated management could focus on one management action to abate a dominant threat or on a strategy comprising multiple actions to abate multiple threats. Furthermore management could be undertaken at sites that are in close proximity to reduce costs. We used cost-effectiveness analysis to prioritize investments in fire management, controlling invasive predators, and reducing grazing pressure in a bio-diverse region of southeastern Queensland, Australia. We compared outcomes of 5 management approaches based on different assumptions about interactions and quantified how investment needed, benefits expected, and the locations prioritized for implementation differed when interactions were taken into account. Managing for interactions altered decisions about where to invest and in which actions to invest and had the potential to deliver increased investment efficiency. Differences in high priority locations and actions were greatest between the approaches when we made different assumptions about how management actions deliver benefits through threat abatement: either all threats must be managed to conserve species or only one management action may be required. Threatened species management that does not consider interactions between actions may result in misplaced investments or misguided expectations of the effort required to mitigate threats to species.

  2. The Public Place of Central Libraries: Findings from Toronto and Vancouver.

    Science.gov (United States)

    Leckie, Gloria J.; Hopkins, Jeffrey

    2002-01-01

    Discussion of the social roles of public libraries focuses on the public use of central libraries in Toronto and Vancouver. Results support the notion that central libraries fulfill ideals of public place, and that private market interests represent a threat to its role as a public place. (Contains 99 references.) (Author/LRW)

  3. Towards Formal Analysis of Insider Threats for Auctions

    DEFF Research Database (Denmark)

    Kammueller, Florian; Kerber, Manfred; Probst, Christian W.

    2016-01-01

    This paper brings together the world of insider threats and auctions. For online-auction systems, like eBay, but also for high-value one-off auction algorithms as they are used for selling radio wave frequencies, the use of rigorous machine supported modelling and verification techniques is meani......This paper brings together the world of insider threats and auctions. For online-auction systems, like eBay, but also for high-value one-off auction algorithms as they are used for selling radio wave frequencies, the use of rigorous machine supported modelling and verification techniques...... is meaningful to prove correctness and scrutinize vulnerability to security and privacy attacks. Surveying the threats in auctions and insider collusions, we present an approach to model and analyze auction protocols for insider threats using the interactive theorem prover Isabelle. As a case study, we use...... the cocaine auction protocol that represents a nice combination of cryptographic techniques, protocols, and privacy goals suitable for highlighting insider threats for auctions....

  4. An Expert System For Multispectral Threat Assessment And Response

    Science.gov (United States)

    Steinberg, Alan N.

    1987-05-01

    A concept has been defined for an automatic system to manage the self-defense of a combat aircraft. Distinctive new features of this concept include: a. the flexible prioritization of tasks and coordinated use of sensor, countermeasures, flight systems and weapons assets by means of an automated planning function; b. the integration of state-of-the-art data fusion algorithms with event prediction processing; c. the use of advanced Artificial Intelligence tools to emulate the decision processes of tactical EW experts. Threat Assessment functions (a) estimate threat identity, lethality and intent on the basis of multi-spectral sensor data, and (b) predict the time to critical events in threat engagements (e.g., target acquisition, tracking, weapon launch, impact). Response Management functions (a) select candidate responses to reported threat situations; (b) estimate the effects of candidate actions on survival; and (c) coordinate the assignment of sensors, weapons and countermeasures with the flight plan. The system employs Finite State Models to represent current engagements and to predict subsequent events. Each state in a model is associated with a set of observable features, allowing interpretation of sensor data and adaptive use of sensor assets. Defined conditions on state transitions allow prediction of times to critical future states and are used in planning self-defensive responses, which are designed either to impede a particular state transition or to force a transition to a lower threat state.

  5. If it bleeds, it leads: separating threat from mere negativity.

    Science.gov (United States)

    Kveraga, Kestutis; Boshyan, Jasmine; Adams, Reginald B; Mote, Jasmine; Betz, Nicole; Ward, Noreen; Hadjikhani, Nouchine; Bar, Moshe; Barrett, Lisa F

    2015-01-01

    Most theories of emotion hold that negative stimuli are threatening and aversive. Yet in everyday experiences some negative sights (e.g. car wrecks) attract curiosity, whereas others repel (e.g. a weapon pointed in our face). To examine the diversity in negative stimuli, we employed four classes of visual images (Direct Threat, Indirect Threat, Merely Negative and Neutral) in a set of behavioral and functional magnetic resonance imaging studies. Participants reliably discriminated between the images, evaluating Direct Threat stimuli most quickly, and Merely Negative images most slowly. Threat images evoked greater and earlier blood oxygen level-dependent (BOLD) activations in the amygdala and periaqueductal gray, structures implicated in representing and responding to the motivational salience of stimuli. Conversely, the Merely Negative images evoked larger BOLD signal in the parahippocampal, retrosplenial, and medial prefrontal cortices, regions which have been implicated in contextual association processing. Ventrolateral as well as medial and lateral orbitofrontal cortices were activated by both threatening and Merely Negative images. In conclusion, negative visual stimuli can repel or attract scrutiny depending on their current threat potential, which is assessed by dynamic shifts in large-scale brain network activity.

  6. Brain Mechanisms of Social Threat Effects on Working Memory.

    Science.gov (United States)

    van Ast, V A; Spicer, J; Smith, E E; Schmer-Galunder, S; Liberzon, I; Abelson, J L; Wager, T D

    2016-02-01

    Social threat can have adverse effects on cognitive performance, but the brain mechanisms underlying its effects are poorly understood. We investigated the effects of social evaluative threat on working memory (WM), a core component of many important cognitive capabilities. Social threat impaired WM performance during an N-back task and produced widespread reductions in activation in lateral prefrontal cortex and intraparietal sulcus (IPS), among other regions. In addition, activity in frontal and parietal regions predicted WM performance, and mediation analyses identified regions in the bilateral IPS that mediated the performance-impairing effects of social threat. Social threat also decreased connectivity between the IPS and dorsolateral prefrontal cortex, while increasing connectivity between the IPS and the ventromedial prefrontal cortex, a region strongly implicated in the generation of autonomic and emotional responses. Finally, cortisol response to the stressor did not mediate WM impairment but was rather associated with protective effects. These results provide a basis for understanding interactions between social and cognitive processes at a neural systems level.

  7. Credibility of Deterrence Threats- A Social Psychological Perspective

    Directory of Open Access Journals (Sweden)

    Ahmed Sheikh

    1972-01-01

    Full Text Available In view of the prevailing ambiguities, impressionistic beliefs and perhaps distortions that shroud the contemporary deterrence theory and the various strategies of deterrence associated with it, this paper attempts to break fresh grounds, particularly in the area of threat credibility. By focusing the level of analysis somewhere between the individual personality and social structures and thus using a social psychological approach, it attempts to explain the behaviour (as related to the credibility of deterrence threats of national decision-makers, during acute international crises. After analyzing and re-evaluating the relevant literature in the field, the paper presents a functional model of threat perception involving two opponents. The model takes into account such variables as: (1 basic human needs; (2 role of reference groups; (3credibility and specificity of international threats; (4 leaders intentions and predispositions; and (5 self-perception of threats. The major conclusions of the paper are: (1 no communicative means for influencing human behaviour are uniformally effective because of the problem of distortion of perception; evidence suggests in most cases rationality under high fear is impaired because fear tends to reduce the range of clues which are available for the consideration of the threatened party.

  8. Assessment of terrorist threats to the Canadian energy sector

    Energy Technology Data Exchange (ETDEWEB)

    Shull, A. [Carleton Univ., Ottawa, ON (Canada). Norman Paterson School of International Affairs]|[Ottawa Univ., ON (Canada). Faculty of Law

    2006-03-15

    A critical terrorist threat assessment of Canadian energy systems was presented, as well as an analysis of integrated continental systems. Recent responses to heightened threat levels on the part of the Canadian government have ranged from information sharing to emergency preparedness and disaster mitigation strategies. This paper examined threats that the energy sector has traditionally encountered and argued that response capabilities do not match current threats posed by terrorism. The potential of a terrorist attack on the Canadian energy infrastructure is significant and has been referred to as a possible target by terrorist organizations. Actions taken by the Canadian government in response to heightened threat levels were examined. A review of energy industry security measures included outlines of: the natural gas industry, the electric sector, and nuclear reactors and waste. It was noted that not all elements of the critical energy infrastructure share the same level of risk. Recommendations included increased information sharing between government agencies and the private sector; resiliency standards in densely populated areas; and insulating the energy grid against a cascading blackout through the use of DC rather than AC lines. 59 refs.

  9. Benefits of integrating complementarity into priority threat management.

    Science.gov (United States)

    Chadés, Iadine; Nicol, Sam; van Leeuwen, Stephen; Walters, Belinda; Firn, Jennifer; Reeson, Andrew; Martin, Tara G; Carwardine, Josie

    2015-04-01

    Conservation decision tools based on cost-effectiveness analysis are used to assess threat management strategies for improving species persistence. These approaches rank alternative strategies by their benefit to cost ratio but may fail to identify the optimal sets of strategies to implement under limited budgets because they do not account for redundancies. We devised a multiobjective optimization approach in which the complementarity principle is applied to identify the sets of threat management strategies that protect the most species for any budget. We used our approach to prioritize threat management strategies for 53 species of conservation concern in the Pilbara, Australia. We followed a structured elicitation approach to collect information on the benefits and costs of implementing 17 different conservation strategies during a 3-day workshop with 49 stakeholders and experts in the biodiversity, conservation, and management of the Pilbara. We compared the performance of our complementarity priority threat management approach with a current cost-effectiveness ranking approach. A complementary set of 3 strategies: domestic herbivore management, fire management and research, and sanctuaries provided all species with >50% chance of persistence for $4.7 million/year over 20 years. Achieving the same result cost almost twice as much ($9.71 million/year) when strategies were selected by their cost-effectiveness ranks alone. Our results show that complementarity of management benefits has the potential to double the impact of priority threat management approaches.

  10. A hydrological-economic model for sustainable groundwater use in sparse-data drylands: Application to the Amtoudi Oasis in southern Morocco, northern Sahara.

    Science.gov (United States)

    Alcalá, Francisco J; Martínez-Valderrama, Jaime; Robles-Marín, Pedro; Guerrera, Francesco; Martín-Martín, Manuel; Raffaelli, Giuliana; de León, Julián Tejera; Asebriy, Lahcen

    2015-12-15

    A hydrological-economic model is introduced to describe the dynamics of groundwater-dependent economics (agriculture and tourism) for sustainable use in sparse-data drylands. The Amtoudi Oasis, a remote area in southern Morocco, in the northern Sahara attractive for tourism and with evidence of groundwater degradation, was chosen to show the model operation. Governing system variables were identified and put into action through System Dynamics (SD) modeling causal diagrams to program basic formulations into a model having two modules coupled by the nexus 'pumping': (1) the hydrological module represents the net groundwater balance (G) dynamics; and (2) the economic module reproduces the variation in the consumers of water, both the population and tourists. The model was operated under similar influx of tourists and different scenarios of water availability, such as the wet 2009-2010 and the average 2010-2011 hydrological years. The rise in international tourism is identified as the main driving force reducing emigration and introducing new social habits in the population, in particular concerning water consumption. Urban water allotment (PU) was doubled for less than a 100-inhabitant net increase in recent decades. The water allocation for agriculture (PI), the largest consumer of water, had remained constant for decades. Despite that the 2-year monitoring period is not long enough to draw long-term conclusions, groundwater imbalance was reflected by net aquifer recharge (R) less than PI+PU (Gtechnology actions are tentatively proposed to mitigate groundwater degradation, such as: wastewater capture, treatment, and reuse for irrigation; storm-water harvesting for irrigation; and active maintenance of the irrigation system to improve its efficiency.

  11. Cave invertebrates in Espírito Santo state, Brazil: a primary analysis of endemism, threats and conservation priorities

    Directory of Open Access Journals (Sweden)

    Marconi Souza Silva

    2015-08-01

    Full Text Available The cave-dwelling invertebrates were studied according to their composition, biodiversity, distribution and threats in the Atlantic Forest Central Biodiversity Corridor, a priority area for conservation actions in Brazil. Twelve obligate cave species were found, plus 495 troglophile species. Araneae (103 spp., Coleoptera (61 spp., Diptera (56 spp. and Lepidoptera (38 spp. were the richest taxa. The richness was higher in the carbonate caves (63 spp., sd = 16.7 and the highest diversity in granitic caves (H´= 2.68, sd = 0.5. The spatial turnover was 63.45 and similarity less than 30%. The total richness was correlated with the linear extension of the caves (Rs = 0.757, p ≤ 0.05. Surrounding area deforestation and religious and tourist use were the main threats. Emergency attention is recommended regarding protective actions, management and conservation of caves of extremely high biological importance.

  12. Advanced Research Workshop on Preparedness for Nuclear and Radiological Threats

    CERN Document Server

    Diamond, David; Nuclear Threats and Security Challenges

    2015-01-01

    With the dissolution of the Soviet Union the nuclear threats facing the world are constantly evolving and have grown more complex since the end of the Cold War. The diversion of complete weapon systems or nuclear material to rogue nations and terrorist organizations has increased. The events of the past years have proved the necessity to reevaluate these threats on a level never before considered.  In recognition that no single country possesses all of the answers to the critical scientific, institutional and legal questions associated with combating nuclear and radiological terrorism, the NATO Advanced Research Workshop on “Preparedness for Nuclear and Radiological Threats” and this proceeding was structured to promote wide-ranging, multi-national exploration of critical technology needs and underlying scientific challenges to reducing the threat of nuclear/radiological terrorism; to illustrate through country-specific presentations how resulting technologies were used in national programs; and to outli...

  13. Threat Assessment of Targets Based on Support Vector Machine

    Institute of Scientific and Technical Information of China (English)

    CAI Huai-ping; LIU Jing-xu; CHEN Ying-wu

    2006-01-01

    In the context of cooperative engagement of armored vehicles, the threat factors of offensive targets are analyzed, and a threat assessment (TA) model is built based on a support v.ector machine (SVM) method. The SVM-based model has some advantages over the traditional method-based models: the complex factors of threat are considered in the cooperative engagement; the shortcomings of neural networks, such as local minimum and "over fitting", are overcome to improve the generalization ability; its operation speed is high and meets the needs of real time C2 of cooperative engagement; the assessment results could be more reasonable because of its self-learning capability. The analysis and simulation indicate that the SVM method is an effective method to resolve the TA problems.

  14. Existential and psychological problems connected with Threat Predicting Process

    Directory of Open Access Journals (Sweden)

    Mamcarz Piotr

    2014-01-01

    Full Text Available The aim of the article is to present a very important phenomenon affecting human integrity and homeostasis that is Threat Prediction Process. This process can be defined as “experiencing apprehension concerning results of potential/ actual dangers,” (Mamcarz, 2015 oscillating in terminological area of anxiety, fear, stress, restlessness. Moreover, it highlights a cognitive process distinctive for listed phenomenon’s. The process accompanied with technological and organization changes increases number of health problems affecting many populations. Hard work conditions; changing life style; or many social and political threats have influence on people’s quality of life that are even greater and more dangerous than physical and psychological factors, which, in turn, have much more consequences for human normal functioning. The present article is based on chosen case studies of a qualitative analysis of threat prediction process

  15. Estimation of the threat of IEMI to complex electronic systems

    Directory of Open Access Journals (Sweden)

    R. Kanyou Nana

    2009-05-01

    Full Text Available The threat of ultra wideband (UWB sources is interesting for military issues. This paper summarizes information concerning the voltages generated from some commercially available UWB generator systems and their produced electromagnetic fields. The paper focuses on the coupling of UWB fields into electronic equipment and discusses possible modeling and measurement techniques to estimate such a threat for modern ships. An evaluation procedure for the determination of the induced voltage at the input of an electronic component is presented. This method is based on the computation of the internal electric field and the measurements on a test network, which is similar to the structure of the steering control cabling. It allows the estimation of the potential threat for the ship's electronic equipment due to the exposal to UWB emitting sources.

  16. Emotion guided threat detection: expecting guns where there are none.

    Science.gov (United States)

    Baumann, Jolie; Desteno, David

    2010-10-01

    Five experiments examine whether the ability of emotions to influence judgments of threat extends to a very basic process inherent in threat detection: object recognition. Participants experiencing different emotions were asked to make rapid judgments about whether target individuals were holding guns or neutral objects. Results across 4 experiments supported the hypothesis that anger increases the probability that neutral objects will be misidentified as ones related to violence, but not the converse. Of import, the findings demonstrate that this bias is not a simple function of the negative valence of an emotional state, but stems from specific threat-relevant cues provided by anger. Direct manipulation of participants' expectancies for encountering guns in the environment is shown not only to remove the bias among angry individuals when set to be low but also to produce a corresponding bias among neutral participants when set to be high. A 5th study demonstrates that the bias is amenable to correction given sufficient ability.

  17. A vector relational data modeling approach to Insider threat intelligence

    Science.gov (United States)

    Kelly, Ryan F.; Anderson, Thomas S.

    2016-05-01

    We address the problem of detecting insider threats before they can do harm. In many cases, co-workers notice indications of suspicious activity prior to insider threat attacks. A partial solution to this problem requires an understanding of how information can better traverse the communication network between human intelligence and insider threat analysts. Our approach employs modern mobile communications technology and scale free network architecture to reduce the network distance between human sensors and analysts. In order to solve this problem, we propose a Vector Relational Data Modeling approach to integrate human "sensors," geo-location, and existing visual analytics tools. This integration problem is known to be difficult due to quadratic increases in cost associated with complex integration solutions. A scale free network integration approach using vector relational data modeling is proposed as a method for reducing network distance without increasing cost.

  18. Dimensions of early experience and neural development: deprivation and threat.

    Science.gov (United States)

    Sheridan, Margaret A; McLaughlin, Katie A

    2014-11-01

    Over the past decade, a growing area of research has focused on adverse childhood experiences (ACEs) and their impacts on neural and developmental outcomes. Work in the field to-date has generally conceptualized ACEs in terms of exposure to stress while overlooking the underlying dimensions of environmental experience that may distinctly impact neural development. Here, we propose a novel framework that differentiates between deprivation (absence of expected cognitive and social input) and threat (presence of a threat to one's physical integrity). We draw support for the neural basis of this distinction from studies on fear learning and sensory deprivation in animals to highlight potential mechanisms through which experiences of threat and deprivation could affect neural structure and function in humans.

  19. Stereotype Threat in Organizations: An Examination of its Scope, Triggers, and Possible Interventions

    OpenAIRE

    Laura J. Kray; Shirako, Aiwa

    2009-01-01

    This chapter explores stereotype threat in organizational contexts. Building on the understanding that stereotype threat involves concerns about confirming a negative stereotype about one’s group, we begin by elucidating the scope of potential stereotype threat effects in organizations. We first examine the ubiquity of evaluations in organizations, which are at the heart of stereotype threat. Next we specify the potential psychological consequences of stereotype threat on targeted individua...

  20. Phishing - A Growing Threat to E-Commerce

    CERN Document Server

    Banday, M Tariq

    2011-01-01

    In today's business environment, it is difficult to imagine a workplace without access to the web, yet a variety of email born viruses, spyware, adware, Trojan horses, phishing attacks, directory harvest attacks, DoS attacks, and other threats combine to attack businesses and customers. This paper is an attempt to review phishing - a constantly growing and evolving threat to Internet based commercial transactions. Various phishing approaches that include vishing, spear phishng, pharming, keyloggers, malware, web Trojans, and others will be discussed. This paper also highlights the latest phishing analysis made by Anti-Phishing Working Group (APWG) and Korean Internet Security Center.

  1. Soluble iron nutrients in Saharan dust over the central Amazon rainforest

    Science.gov (United States)

    Rizzolo, Joana A.; Barbosa, Cybelli G. G.; Borillo, Guilherme C.; Godoi, Ana F. L.; Souza, Rodrigo A. F.; Andreoli, Rita V.; Manzi, Antônio O.; Sá, Marta O.; Alves, Eliane G.; Pöhlker, Christopher; Angelis, Isabella H.; Ditas, Florian; Saturno, Jorge; Moran-Zuloaga, Daniel; Rizzo, Luciana V.; Rosário, Nilton E.; Pauliquevis, Theotonio; Santos, Rosa M. N.; Yamamoto, Carlos I.; Andreae, Meinrat O.; Artaxo, Paulo; Taylor, Philip E.; Godoi, Ricardo H. M.

    2017-02-01

    The intercontinental transport of aerosols from the Sahara desert plays a significant role in nutrient cycles in the Amazon rainforest, since it carries many types of minerals to these otherwise low-fertility lands. Iron is one of the micronutrients essential for plant growth, and its long-range transport might be an important source for the iron-limited Amazon rainforest. This study assesses the bioavailability of iron Fe(II) and Fe(III) in the particulate matter over the Amazon forest, which was transported from the Sahara desert (for the sake of our discussion, this term also includes the Sahel region). The sampling campaign was carried out above and below the forest canopy at the ATTO site (Amazon Tall Tower Observatory), a near-pristine area in the central Amazon Basin, from March to April 2015. Measurements reached peak concentrations for soluble Fe(III) (48 ng m-3), Fe(II) (16 ng m-3), Na (470 ng m-3), Ca (194 ng m-3), K (65 ng m-3), and Mg (89 ng m-3) during a time period of dust transport from the Sahara, as confirmed by ground-based and satellite remote sensing data and air mass backward trajectories. Dust sampled above the Amazon canopy included primary biological aerosols and other coarse particles up to 12 µm in diameter. Atmospheric transport of weathered Saharan dust, followed by surface deposition, resulted in substantial iron bioavailability across the rainforest canopy. The seasonal deposition of dust, rich in soluble iron, and other minerals is likely to assist both bacteria and fungi within the topsoil and on canopy surfaces, and especially benefit highly bioabsorbent species. In this scenario, Saharan dust can provide essential macronutrients and micronutrients to plant roots, and also directly to plant leaves. The influence of this input on the ecology of the forest canopy and topsoil is discussed, and we argue that this influence would likely be different from that of nutrients from the weathered Amazon bedrock, which otherwise provides the

  2. Radiological threat, public and media: a psychosociological view

    Energy Technology Data Exchange (ETDEWEB)

    Arciszewski, T. [University Rene Descartes - Paris 5, 92 - Boulogne (France)

    2006-07-01

    Nuclear risk has become a major social communication along the 20. century because of its critical socio-political impact. That communication is not limited to expert speeches and simple acceptation. The way people understand that kind of threat is based on beliefs and on imaginary pictures. Consequently, and because it shapes people attitude, expectations and behaviours, their analysis is a key for policy and prevention. We will present, in the light of the research on risk perception and social psychology theoretical background, how people can manage with the nuclear fear. Some particular points will be studied: the nature of nuclear threat and fear, the cultural and media coverage and the consequences of this threat on behaviour. We will first focus on what a societal threat is and of which nature is the nuclear threat. We will rely on statistical data on risk perception. We have to consider the two main fields of information: first the nuclear threat as a mass destruction weapon and second, the radiological risk as a consequence of civil use of radiological material. Those two aspects, deeply related for most people, make the roots for the described fears. Then, the perception of the risks relative to nuclear is necessarily influenced by this representation. The representation of the nuclear power is and will be for next years, related to the nuclear mushroom as experimentally pointed o ut by Fiske, both with the abnormal children of Chernobyl. How can we change that vision? Not to be a liar, it will be hard work because it a old story, a long construction of what will be the future of mankind, something deeply influenced by media, movie, geopolitical facts like the cold war or technological accident like Three Mile Island or Chernobyl. It has to deal with the problem of media transmission of fears, which is a problem in itself, but due to the scientific base of our problem, particularly relevant. Moreover, there is a strong cultural background that maintains

  3. Flaviviruses, an expanding threat in public health: focus on dengue, West Nile, and Japanese encephalitis virus.

    Science.gov (United States)

    Daep, Carlo Amorin; Muñoz-Jordán, Jorge L; Eugenin, Eliseo Alberto

    2014-12-01

    The flaviviruses dengue, West Nile, and Japanese encephalitis represent three major mosquito-borne viruses worldwide. These pathogens impact the lives of millions of individuals and potentially could affect non-endemic areas already colonized by mosquito vectors. Unintentional transport of infected vectors (Aedes and Culex spp.), traveling within endemic areas, rapid adaptation of the insects into new geographic locations, climate change, and lack of medical surveillance have greatly contributed to the increase in flaviviral infections worldwide. The mechanisms by which flaviviruses alter the immune and the central nervous system have only recently been examined despite the alarming number of infections, related deaths, and increasing global distribution. In this review, we will discuss the expansion of the geographic areas affected by flaviviruses, the potential threats to previously unaffected countries, the mechanisms of pathogenesis, and the potential therapeutic interventions to limit the devastating consequences of these viruses.

  4. Stereotype Threat and Test Performance: A Primer for School Psychologists

    Science.gov (United States)

    Jordan, Alexander H.; Lovett, Benjamin J.

    2007-01-01

    Ethical guidelines require school psychologists to ensure that their assessment practices are nondiscriminatory, but typical discussions on this topic neglect the possible discriminatory effects of cultural stereotypes on assessment results. Recent research on "stereotype threat" shows that students' knowledge of stereotype-based negative…

  5. Threat, Intimidation, and Student Financial Market Knowledge: An Empirical Study

    Science.gov (United States)

    Ford, Matthew W.; Devoto, Steve; Kent, Daniel W.; Harrison, Todd

    2007-01-01

    Threat emanating from financial markets may intimidate college students to some degree. In this article, the authors considered the influence of such intimidation on student financial market knowledge. They hypothesized a negative relationship between intimidation and market knowledge. An empirical study of over 150 undergraduate business school…

  6. Globalisation of water: opportunities and threats of virtual water trade

    NARCIS (Netherlands)

    Chapagain, A.K.

    2006-01-01

    Where the river basin is generally seen as the appropriate unit for analyzing freshwater availability and use, it becomes increasingly important to put freshwater issues in a global context. The book analyses the opportunities and threats of international virtual water trade in the context of solvin

  7. Community Violence Exposure, Threat Appraisal, and Adjustment in Adolescents

    Science.gov (United States)

    Kliewer, Wendy; Sullivan, Terri N.

    2008-01-01

    Validity data are presented for a new measure of threat appraisals in response to community violence. Adolescents (N = 358; 45% male; 91% African American, M = 12.10 years, SD = 1.63) and their maternal caregivers participated in two waves of a longitudinal interview study focused on the consequences of exposure to community violence. Structural…

  8. Uncovering Embedded Face Threat Mitigation in Landscape Architecture Critique Feedback

    Science.gov (United States)

    Housley Gaffney, Amy L.

    2015-01-01

    Receiving public feedback on academic work may threaten students' face, particularly when such feedback is critical. One way that feedback may be cushioned is through face-threat mitigation techniques. I analyzed the use of such techniques in the feedback given by faculty and professionals to landscape architecture students as preparation for…

  9. Performance Assessment of Communication Enhancement Devices TEA HI Threat Headset

    Science.gov (United States)

    2015-08-01

    against impulsive noises (for example, gun shots or explosions), and were measured in accordance with ANSI S12.42-2010.2 Understanding the noise...measurements. The TEA HI Threat headset could be worn with the headband under the ACH or mounted directly to the helmet’s Accessory Rail Connector

  10. Network Threat Ratings in Conventional DREAD Model Using Fuzzy Logic

    Directory of Open Access Journals (Sweden)

    Ak.Ashakumar Singh

    2012-01-01

    Full Text Available One of the most popular techniques to deal with ever growing risks associated with security threats is DREAD model. It is used for rating risk of network threats identified in the abuser stories. In this model network threats needs to be defined by sharp cutoffs. However, such precise distribution is not suitable for risk categorization as risks are vague in nature and deals with high level of uncertainty. In view of these risk factors, the paper proposes a novel fuzzy approach using DREAD model for computing risk level that ensures better evaluation of imprecise concepts. Thus, it provides the capacity to include subjectivity and uncertainty during risk ranking. These threat parameters need to be frequently updated based on feedback from implementation of previous parameters. These feedback are always stated in the form of ordinal ratings, e.g. "high speed", "average performance", "good condition". Different people can describe different values to these ordinal ratings without a clear-cut reason or scientific basis. There is need for a way or means to transform vague ordinal ratings to more appreciable and precise numerical estimates. The paper transforms the ordinal performance ratings of some system performance parameters to numerical ratings using Fuzzy Logic.

  11. The effects of takeover threats on shareholders and firm value

    NARCIS (Netherlands)

    Haan, MA; Riyanto, Y

    2006-01-01

    We study the role of takeover threats as a corporate control mechanism using [Aghion, P., Tirole, J., 1997. Formal and real authority in organizations. Journal of Political Economy 105, 1-29] model of formal and real authority. Shareholders do not monitor the manager's actions since ownership is wid

  12. Computer Viruses and Related Threats: A Management Guide.

    Science.gov (United States)

    Wack, John P.; Carnahan, Lisa J.

    This document contains guidance for managing the threats of computer viruses, Trojan horses, network worms, etc. and related software along with unauthorized use. It is geared towards managers of end-user groups, managers dealing with multi-user systems, personal computers, and networks. The guidance is general and addresses the vulnerabilities…

  13. Perfectionism Moderates Stereotype Threat Effects on STEM Majors' Academic Performance

    Science.gov (United States)

    Rice, Kenneth G.; Lopez, Frederick G.; Richardson, Clarissa M. E.; Stinson, Jennifer M.

    2013-01-01

    Using a randomized, between-subjects experimental design, we tested hypotheses that self-critical perfectionism would moderate the effects of subtle stereotype threat (ST) for women and students in underrepresented racial/ethnic groups who are pursuing traditional degrees in science, technology, engineering, or math (STEM). A diverse sample of…

  14. New and emerging threats of cyber crime and terrorism

    NARCIS (Netherlands)

    Luiijf, H.A.M.

    2014-01-01

    Advancements in information and communication technologies (ICT) inextricably bring new threats to the end-users and society. However, the last 40 years have shown that many of the same cyber security design and programming failures occur over and over again when a new ICT innovation and development

  15. Collective Threat, Trust, and the Sense of Personal Control

    Science.gov (United States)

    Ross, Catherine E.

    2011-01-01

    A threatening and dangerous neighborhood may produce distressing emotions of anxiety, anger, and depression among the individuals who live there because residents find these neighborhoods subjectively alienating. The author introduces the idea that neighborhood disorder indicates collective threat, which is alienating--shaping perceptions of…

  16. Concealed Threat Detection at Multiple Frames-per-second

    Energy Technology Data Exchange (ETDEWEB)

    Chang, J T

    2005-11-08

    In this LDRD project, our research purpose is to investigate the science and technology necessary to enable real-time array imaging as a rapid way to detect hidden threats through obscurants such as smoke, fog, walls, doors, and clothing. The goal of this research is to augment the capabilities of protective forces in concealed threat detection. In the current context, threats include people as well as weapons. In most cases, security personnel must make very fast assessments of a threat based upon limited amount of data. Among other attributes, UWB has been shown and quantified to penetrate and propagate through many materials (wood, some concretes, non-metallic building materials, some soils, etc.) while maintaining high range resolution. We have build collaborations with university partners and government agencies. We have considered the impact of psychometrics on target recognition and identification. Specifically we have formulated images in real-time that will engage the user's vision system in a more active way to enhance image interpretation capabilities. In this project, we are researching the use of real time (field programmable gate arrays) integrated with high resolution (cm scale), ultra wide band (UWB) electromagnetic signals for imaging personnel through smoke and walls. We evaluated the ability of real-time UWB imaging for detecting smaller objects, such as concealed weapons that are carried by the obscured personnel. We also examined the cognitive interpretation process of real time UWB electromagnetic images.

  17. Facing Freeze: Social Threat Induces Bodily Freeze in Humans

    NARCIS (Netherlands)

    Roelofs, K.; Hagenaars, M.A.; Stins, J.F.

    2010-01-01

    Freezing is a common defensive response in animals threatened by predators. It is characterized by reduced body motion and decreased heart rate (bradycardia). However, despite the relevance of animal defense models in human stress research, studies have not shown whether social threat cues elicit si

  18. Cognitive bias for pictorial and linguistic threat cues in children

    NARCIS (Netherlands)

    van den Hout, M.; Hoekzema, B.; de Jong, P.; Kindt, M.

    2000-01-01

    The present study was designed to test the conditions under which threat-related cognitive bias can be observed in anxious children. Measures of cognitive bias for threatening words and pictures were obtained from 55 spider fearful children and 58 non-fearful children (aged 8-11 yrs) in the 1st expe

  19. Cognitive bias for pictorial and linguistic threat cues in children

    NARCIS (Netherlands)

    Kindt, M; van den Hout, M; de Jong, Peter; Hoekzema, B

    2000-01-01

    The present study was designed to test the conditions under which threat-related cognitive bias can be observed in anxious children. Measures of cognitive bias for threatening words and pictures were obtained from spider fearful children (N = 55) and non-fearful children (N = 58) aged 8-11 in the fi

  20. Common Sense Guide to Mitigating Insider Threats 4th Edition

    Science.gov (United States)

    2012-12-01

    ranged from late teens to retirement age. There is not a standard profile that can be used to identify a malicious insider. The CERT Insider Threat...contractor, business partner, or candidate for a position, such as race, disability, parenthood, or sexual orientation, which could open the door to