Inside the Black Box of Internet Adoption: The Role of Migration and Networking in Internet Penetration in West Africa

Abstract The analysis of land–atmosphere feedbacks requires detailed representation of land processes in atmospheric models. The focus here is on runoff–infiltration partitioning and resolved overland flow. In the standard version of WRF, runoff–infiltration partitioning is described as a purely vertical process. In WRF-Hydro, runoff is enhanced with lateral water flows. The study region is the Sissili catchment (12 800 km2) in West Africa, and the study period is from March 2003 to February 2004. The WRF setup here includes an outer and inner domain at 10- and 2-km resolution covering the West Africa and Sissili regions, respectively. In this WRF-Hydro setup, the inner domain is coupled with a subgrid at 500-m resolution to compute overland and river flow. Model results are compared with TRMM precipitation, model tree ensemble (MTE) evapotranspiration, Climate Change Initiative (CCI) soil moisture, CRU temperature, and streamflow observation. The role of runoff–infiltration partitioning and resolved overland flow on land–atmosphere feedbacks is addressed with a sensitivity analysis of WRF results to the runoff–infiltration partitioning parameter and a comparison between WRF and WRF-Hydro results, respectively. In the outer domain, precipitation is sensitive to runoff–infiltration partitioning at the scale of the Sissili area (~100 × 100 km2), but not of area A (500 × 2500 km2). In the inner domain, where precipitation patterns are mainly prescribed by lateral boundary conditions, sensitivity is small, but additionally resolved overland flow here clearly increases infiltration and evapotranspiration at the beginning of the wet season when soils are still dry. The WRF-Hydro setup presented here shows potential for joint atmospheric and terrestrial water balance studies and reproduces observed daily discharge with a Nash–Sutcliffe model efficiency coefficient of 0.43.

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Spatial spread of the West Africa Ebola epidemic

Royal Society Open Science ◽

10.1098/rsos.160294 ◽

2016 ◽

Vol 3 (8) ◽

pp. 160294 ◽

Cited By ~ 40

Author(s):

Andrew M. Kramer ◽

J. Tomlin Pulliam ◽

Laura W. Alexander ◽

Andrew W. Park ◽

Pejman Rohani ◽

...

Keyword(s):

West Africa ◽

Sierra Leone ◽

Ebola Virus ◽

Emerging Diseases ◽

Relative Probability ◽

Effective Response ◽

Spatial Spread ◽

Force Of Infection ◽

International Border

Controlling Ebola outbreaks and planning an effective response to future emerging diseases are enhanced by understanding the role of geography in transmission. Here we show how epidemic expansion may be predicted by evaluating the relative probability of alternative epidemic paths. We compared multiple candidate models to characterize the spatial network over which the 2013–2015 West Africa epidemic of Ebola virus spread and estimate the effects of geographical covariates on transmission during peak spread. The best model was a generalized gravity model where the probability of transmission between locations depended on distance, population density and international border closures between Guinea, Liberia and Sierra Leone and neighbouring countries. This model out-performed alternative models based on diffusive spread, the force of infection, mobility estimated from cell phone records and other hypothesized patterns of spread. These findings highlight the importance of integrated geography to epidemic expansion and may contribute to identifying both the most vulnerable unaffected areas and locations of maximum intervention value.

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Intimate partner sexual and physical violence among women in Togo, West Africa: Prevalence, associated factors, and the specific role of HIV infection

Global Health Action ◽

10.3402/gha.v7.23456 ◽

2014 ◽

Vol 7 (1) ◽

pp. 23456 ◽

Cited By ~ 16

Author(s):

Juan Burgos-Soto ◽

Joanna Orne-Gliemann ◽

Gaëlle Encrenaz ◽

Akouda Patassi ◽

Aurore Woronowski ◽

...

Keyword(s):

West Africa ◽

Hiv Infection ◽

Associated Factors ◽

Physical Violence ◽

Intimate Partner ◽

Specific Role

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Consumption and its Externalities: Where Economy Meets Ecology

Global Environmental Politics ◽

10.1162/152638001316881386 ◽

2001 ◽

Vol 1 (3) ◽

pp. 11-30 ◽

Cited By ~ 16

Author(s):

Thomas Princen

Keyword(s):

At Risk ◽

Environmental Policy ◽

Economic Activity ◽

Policy Making ◽

Black Box ◽

Social Scientists ◽

Consumer Sovereignty ◽

Marginal Improvement

If social scientists are going to make a contribution to environmental policy-making that is commensurate with the severity of biophysical trends, they must develop analytic tools that go beyond marginal improvement and a production focus where key actors escape responsibility via distanced commerce and the black box of consumer sovereignty. One means is to construct an ecologically informed “consumption angle” on economic activity. The first approach is to retain the prevailing supply-demand dichotomy and address the externalities of consumption and the role of power in consuming. The second approach is to construe all economic activity as “consuming,” as “using up.” This approach construes material provisioning in the context of hunter/gathering, cultivation, and manufacture and then develops three interpretive layers of excess consumption: background consumption, overconsumption, and misconsumption. An example from timbering illustrates how, by going up and down the decision chain, the consumption angle generates questions about what is consumed and what is put at risk. Explicit assignment of responsibility for excess throughput becomes more likely.

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Modulation of cardiovascular control mechanisms and their interaction

Physiological Reviews ◽

10.1152/physrev.1996.76.1.193 ◽

1996 ◽

Vol 76 (1) ◽

pp. 193-244 ◽

Cited By ~ 126

Author(s):

P. B. Persson

Keyword(s):

Nitric Oxide ◽

Black Box ◽

Control Element ◽

Control Mechanisms ◽

Severity Of Disease ◽

The Brain ◽

Specific Control ◽

Central Level ◽

Shed Light

It is generally held that the role of a specific control element can only be understood within its physiological environment. The reviewed studies make it clear that there is a potent interplay between locally produced substances such as adenosine, nitric oxide, prostaglandins, and various others all interacting with the central level of control. This can occur at central sites (e.g., nitric oxide in the brain) or in the periphery (e.g., neural influence on autoregulation). The interactions are more or less pronounced during specific physiological challenges. Furthermore, several of these interactions are altered under pathological circumstances, and in some cases, the interactions seem to maintain or even augment the severity of disease. When more than three parameters participate in an interaction, the resulting regulation may become extremely complex. If these parameters are nonlinearly coupled with each other, the only way to shed light onto the nature of control network is by treating it as a black box. With the use of spectral analysis or nonlinear methods, it is possible to disentangle the fundamental nature of the system in terms of the complexity and stability. Therefore, modern developments in cardiovascular physiology utilizing these techniques, some of which are derived from the "chaos theory," are reviewed.

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