scholarly journals Projecting the Potential Distribution of Glossina morsitans (Diptera: Glossinidae) under Climate Change Using the MaxEnt Model

Biology ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 1150
Author(s):  
Ruobing Zhou ◽  
Yuan Gao ◽  
Nan Chang ◽  
Tai Gao ◽  
Delong Ma ◽  
...  
Keyword(s):  
Human African Trypanosomiasis ◽  
Climatic Factors ◽  
Sub Saharan Africa ◽  
Large Area ◽  
Glossina Morsitans ◽  
Entropy Model ◽  
Climate Conditions ◽  
Maxent Model ◽  
Sub Saharan ◽  
Suitable Habitats

Glossina morsitans is a vector for Human African Trypanosomiasis (HAT), which is mainly distributed in sub-Saharan Africa at present. Our objective was to project the historical and future potentially suitable areas globally and explore the influence of climatic factors. The maximum entropy model (MaxEnt) was utilized to evaluate the contribution rates of bio-climatic factors and to project suitable habitats for G. morsitans. We found that Isothermality and Precipitation of Wettest Quarter contributed most to the distribution of G. morsitans. The predicted potentially suitable areas for G. morsitans under historical climate conditions would be 14.5 million km2, including a large area of Africa which is near and below the equator, small equatorial regions of southern Asia, America, and Oceania. Under future climate conditions, the potentially suitable areas are expected to decline by about −5.38 ± 1.00% overall, under all shared socioeconomic pathways, compared with 1970–2000. The potentially suitable habitats of G. morsitans may not be limited to Africa. Necessary surveillance and preventive measures should be taken in high-risk regions.

scholarly journals “They Do Not Care about Us Anymore”: Understanding the Situation of Older People in Ghana

2021 ◽  
Vol 18 (5) ◽  
pp. 2337
Author(s):  
Joseph Asumah Braimah ◽  
Mark W. Rosenberg
Keyword(s):  
Older People ◽  
Lived Experiences ◽  
Climatic Factors ◽  
Sub Saharan Africa ◽  
Structural Factors ◽  
Sanitation Services ◽  
Poor Access ◽  
Access To Water ◽  
Sub Saharan ◽  
Sharing Circles

While existing research acknowledges copious challenges faced by older adults (people aged 60 and over) in Ghana and most countries in sub-Saharan Africa, they fail to situate the lived experiences of this vulnerable group within the broader context of health geography and public health. This paper draws insights from ecological systems theory and the “geographies of older people” literature to examine the lived experiences of older people in Ghana. Data for the study were gathered using interviews (42) and sharing circles (10). Our findings reveal a complex mix of experiences consistent with the different levels of the environment. Dominant themes include access to social support, functional impairment and poor health status, social status, poor access to water and sanitation services, food insecurity, economic insecurity, and caregiving burden. These findings support the wide-held notion that the experiences of older people are complex and produced by the interplay of both individual and structural factors. Our findings demonstrate that sociocultural, economic, political, and climatic factors are important consideration in promoting elderly wellbeing and quality of life in Ghana.

scholarly journals Distance from Africa, not climate, explains within-population phenotypic diversity in humans

2008 ◽  
Vol 276 (1658) ◽  
pp. 809-814 ◽  
Author(s):  
Lia Betti ◽  
François Balloux ◽  
William Amos ◽  
Tsunehiko Hanihara ◽  
Andrea Manica
Keyword(s):  
Climatic Factors ◽  
Phenotypic Diversity ◽  
Morphological Diversity ◽  
Sub Saharan Africa ◽  
Relative Role ◽  
Morphometric Traits ◽  
Perfect Agreement ◽  
Skull Measurements ◽  
Sub Saharan

The relative importance of ancient demography and climate in determining worldwide patterns of human within-population phenotypic diversity is still open to debate. Several morphometric traits have been argued to be under selection by climatic factors, but it is unclear whether climate affects the global decline in morphological diversity with increasing geographical distance from sub-Saharan Africa. Using a large database of male and female skull measurements, we apply an explicit framework to quantify the relative role of climate and distance from Africa. We show that distance from sub-Saharan Africa is the sole determinant of human within-population phenotypic diversity, while climate plays no role. By selecting the most informative set of traits, it was possible to explain over half of the worldwide variation in phenotypic diversity. These results mirror those previously obtained for genetic markers and show that ‘bones and molecules’ are in perfect agreement for humans.

scholarly journals Three arenaviruses in three subspecific natal multimammate mouse taxa in Tanzania: same host specificity, but different spatial genetic structure?

2020 ◽  
Vol 6 (2) ◽  
Author(s):  
Laura N Cuypers ◽  
Stuart J E Baird ◽  
Alexandra Hánová ◽  
Tatjana Locus ◽  
Abdul S Katakweba ◽  
...  
Keyword(s):  
Genetic Structure ◽  
Spatial Genetic Structure ◽  
First Record ◽  
Sub Saharan Africa ◽  
Lassa Virus ◽  
Large Area ◽  
Order Of Magnitude ◽  
Morogoro Virus ◽  
Test Specificity ◽  
Sub Saharan

Abstract Mastomys natalensis is widespread in sub-Saharan Africa and hosts several arenavirus species, including the pathogenic zoonotic Lassa virus in West Africa. Mitochondrial lineages sub-divide the range of M. natalensis and have been associated with cryptic structure within the species. To test specificity of arenaviruses to hosts carrying these lineages, we screened 1772 M. natalensis in a large area of Tanzania where three mitochondrial lineages meet. We detected fifty-two individuals that were positive for one of three arenaviruses: Gairo, Morogoro, and Luna virus. This is the first record of Luna virus in Tanzania. We confirmed the specificity of each arenavirus to a distinct host mitochondrial lineage except for three cases in one locality at the centre of a host hybrid zone. No arenaviruses were detected in a large part of the study area. Morogoro and Gairo virus showed differences in prevalence (Morogoro virus lower than Gairo virus) and in genetic structure (Morogoro virus more structured than Gairo virus). However, both viruses have genetic neighbourhood size estimates of the same order of magnitude as Lassa virus. While differences in arenavirus and/or host evolutionary and ecological dynamics may exist, Tanzanian arenaviruses could be suited to model Lassa virus dynamics in M. natalensis.

scholarly journals α-d-Glucopyranosyl-(1→2)-[6-O-(l-tryptophanyl)-β-d-fructofuranoside]

Molbank ◽  
10.3390/m1066 ◽  
2019 ◽  
Vol 2019 (2) ◽  
pp. M1066
Author(s):  
Kwaku Kyeremeh ◽  
Samuel Kwain ◽  
Gilbert Mawuli Tetevi ◽  
Anil Sazak Camas ◽  
Mustafa Camas ◽  
...  
Keyword(s):  
Human African Trypanosomiasis ◽  
2D Nmr ◽  
Sub Saharan Africa ◽  
Western Region ◽  
Mangrove Plant ◽  
Chemical Profiling ◽  
Coptis Japonica ◽  
Full Structure ◽  
Sub Saharan ◽  
Uptake And Metabolism

The Mycobacterium sp. BRS2A-AR2 is an endophyte of the mangrove plant Rhizophora racemosa G. Mey., which grows along the banks of the River Butre, in the Western Region of Ghana. Chemical profiling using 1H-NMR and HRESI-LC-MS of fermentation extracts produced by the strain led to the isolation of the new compound, α-d-Glucopyranosyl-(1→2)-[6-O-(l-tryptophanyl)-β-d–fructofuranoside] or simply tortomycoglycoside (1). Compound 1 is an aminoglycoside consisting of a tryptophan moiety esterified to a disaccharide made up of β-d-fructofuranose and α-d-glucopyranose sugars. The full structure of 1 was determined using UV, IR, 1D, 2D-NMR and HRESI-LC-MS data. When tested against Trypanosoma brucei subsp. brucei, the parasite responsible for Human African Trypanosomiasis in sub-Saharan Africa, 1 (IC50 11.25 µM) was just as effective as Coptis japonica (Thunb.) Makino. (IC50 8.20 µM). The extract of Coptis japonica (Thunb.) Makino. is routinely used as laboratory standard due to its powerful antitrypanosomal activity. It is possible that, compound 1 interferes with the normal uptake and metabolism of tryptophan in the T. brucei subsp. brucei parasite.

scholarly journals Chemotherapy of Human African Trypanosomiasis

2009 ◽  
Vol 2009 ◽  
pp. 1-5 ◽  
Author(s):  
Cyrus J. Bacchi
Keyword(s):  
Combination Chemotherapy ◽  
Human African Trypanosomiasis ◽  
Economic Loss ◽  
Chemotherapeutic Agents ◽  
Sub Saharan Africa ◽  
African Trypanosomiasis ◽  
Physical Suffering ◽  
Rural Clinics ◽  
Sub Saharan

Human Africa trypanosomiasis is a centuries-old disease which has disrupted sub-Saharan Africa in both physical suffering and economic loss. This article presents an update of classic chemotherapeutic agents, in use for >50 years and the recent development of promising non-toxic combination chemotherapy suitable for use in rural clinics.

Malthus and the Theory of ‘Unequal Powers’: Population and Food Production in India, 1800–1947

1986 ◽  
Vol 20 (4) ◽  
pp. 661-701 ◽  
Author(s):  
Simon Commander
Keyword(s):  
Population Growth ◽  
Food Production ◽  
Climatic Factors ◽  
Green Revolution ◽  
Sub Saharan Africa ◽  
Population Growth Rates ◽  
Indian Agriculture ◽  
Sub Saharan ◽  
Food Imports ◽  
Food Commodities

The spectre of a ‘Malthusian’ catastrophe engulfing the subcontinent commands less attention currently than in relatively recent times. This is largely attributable to the greater sense of confidence in the food-grain supply capacity of Indian agriculture in the wake of the Green Revolution. From the mid-1960s through to 1980, output has maintained a growth rate in excess of 2.5% p.a., with yield increments rather than area increments accounting for the major part. Since 1950, per capita net availability of foodgrains has increased by over 20%, while the real price of foodgrains has shown a steady downward trend since 1968. Current projections suggest that self-sufficiency in food production can be sustained through to the end of the century. Yet this remains partly contingent on climatic factors and a slackening trend of population growth. However, population growth rates currently exceed 2.2% p.a. and the relative stability of fertility rates means that a diminution is by no means assured. While supply shortfalls could be met through increased imports of food commodities, the possible emergence of India in the longer term as a food deficitary economy could have serious implications for the international grain market, given the current structure of supply for foodgrains and the growing dependence, particularly in Sub-Saharan Africa, on food imports.

A contribution to the concept and the classification of the bioclimatic unit in Sub-Saharan Africa

Bothalia ◽  
1983 ◽  
Vol 14 (3/4) ◽  
pp. 713-719 ◽  
Author(s):  
J. F. V Phillips
Keyword(s):  
Crop Production ◽  
Climatic Factors ◽  
Ecological Status ◽  
Sub Saharan Africa ◽  
South East Asia ◽  
Natural Conditions ◽  
Policy And Practice ◽  
Sub Saharan ◽  
Vegetation Physiognomy

A bioclimatic unit is an integration of climatic factors (e.g. radiation, humidity complexes) and features modified by physiography and vegetation (biotic communities and associated habitats, i.e. wherever possible, ecosystems). Unit implies an entity irrespective of ecological status and dimensions: these are otherwise differentiated. It often must suffice to use vegetation communities, because information regarding biotic communities or ecosystems is unavailable. Increasingly, disturbance of ‘natural’ conditions makes it imperative to involve man in the classification, demarcation and policy for the development of bioclimatic units. Ignorance regarding the nature and distribution of a climax necessitates using pro- (pre- or post-) climaxes.This is based upon the differentiation in these criteria: climatic (radiation and humidity complexes); vegetation (physiognomy and ecological status) . . . and as these are further modified by physiography and edaphic features (physiognomic differentiation ranges from specific faciations of forest or thicket); wooded savanna (facies ofwoodland, shrubland); facies or faciations of grassland; climatic differentiation ranges from highly humid toarid . . . and further to subdesert and desert. Recommendations respecting policy and practice in pastoral, crop production and forestry development based on this concept have been used in various sectors of Africa. South East Asia and Latin America. Detailed experience has been gained in Natal and elsewhere. Several maps illustrate the application of the concept.

High-resolution weather simulation for sub-Saharan Africa on the World Community Grid

2021 ◽  
Author(s):  
Camille Le Coz ◽  
Qidi Yu ◽  
Lloyd A. Treinish ◽  
Manuel Garcia Alvarez ◽  
Ashley Cryan ◽  
...  
Keyword(s):  
High Resolution ◽  
Wrf Model ◽  
Sub Saharan Africa ◽  
Large Area ◽  
World Community ◽  
The World ◽  
Sub Saharan ◽  
Socio Economic Impact ◽  
One Year ◽  
The Impact

<p>Rainfall in Africa is difficult to estimate accurately due to the large spatial variability. Most of the monsoon rainfall is generated by convective rainstorms that can be very localized, sometimes covering less than 100 km2. The goal of the African Rainfall Project is to run the Weather and Research Forecast (WRF) model for sub-Saharan Africa at a convection-permitting resolution in order to better represent such rainfall events. The resolution will be 1km, which is finer than most studies over Africa, which typically use resolutions of 3km or more. Running WRF for such a large area at such a high resolution is computationally expensive, which is where IBM’s World Community Grid comes in. The World Community Grid (WCG) is part of the Social Corporate Responsibility of IBM that crowdsources unused computing power from volunteers devices and donates it to scientific projects.</p><p>The simulation was adapted to the WCG by dividing the simulation of one year over sub-Saharan Africa in many smaller simulations of 48h over 52 by 52 km domains. These simulations are small enough to be calculated on a single computer of a volunteer at the required resolution. In total, 35609 overlapping domains are covering the whole of sub-Saharan Africa. During the post-processing phase, the smaller simulations are merged back together to obtain one consistent simulation over the whole continent.</p><p>Our main focus is rainfall, as this is the variable with the highest socio-economic impact in Africa. However, the outputs of the simulations include other variables such as the 2m-temperature, the 10m-wind speed and direction. These variables are outputted every 15min. At the end of this project, we will have over 3 billion files for a total of 0.5 PB. The data will be reorganized so that the different variables can be stored, searched and retrieved efficiently. After the reorganization, the data will be made publicly available.</p><p>The first validation step will be to examine the impact of dividing sub-Saharan Africa into many smaller domains. This will be done by comparing the simulation from this project to one large simulation. This simulation is obtained by running WRF at a 1km resolution on a large domain (500km by 1000km) for a shorter period, using Cartesius, the Dutch national computer. The second validation step will be to compare the simulations with satellite data and with in-situ measurements from the TAHMO network (www.tahmo.org).</p>

scholarly journals MIGRATION AND MALARIA IN EUROPE

2012 ◽  
Vol 4 (1) ◽  
pp. e2012014 ◽  
Author(s):  
Begoña Monge-Maillo ◽  
Rogelio López-Vélez
Keyword(s):  
Occupational Exposures ◽  
Clinical Malaria ◽  
Imported Malaria ◽  
Sub Saharan Africa ◽  
Climate Conditions ◽  
Asymptomatic Patients ◽  
Sub Saharan ◽  
The Individual ◽  
Stable Transmission ◽  
Autochthonous Transmission

The proportion of imported malaria cases due to immigrants in Europe has increased during the lasts decades, being the higher rates for those settled immigrants who travel to visit friends and relatives (VFRs) at their country of origin. Cases are mainly due to P. falciparum and Sub-Saharan Africa is the most common origin. Clinically, malaria in immigrants is characterized by a mild clinical presentation with even asymptomatic o delayed malaria cases and low parasitemic level. These characteristics may be explained by a semi-immunity acquired after long periods of time exposed to stable transmission of malaria. Malaria cases among immigrants, even those asymptomatic patients with sub-microscopic parasitemia, could increase the risk of transmission and reintroduction of malaria in certain areas with the adequate vectors and climate conditions. Moreover imported malaria cases by immigrants can also play an important role in the non-vectorial transmission out of endemic area, by blood transfusions, organ transplantation or congenital or occupational exposures. Probably, out of endemic areas, screening of malaria among recent arrived immigrants coming from malaria endemic countries should be performed. These aim to reduce the risk of clinical malaria in the individual as well as to prevent autochthonous transmission of malaria in areas where it had been eradicated.

scholarly journals Forecasting the global extent of invasion of the cereal pest Spodoptera frugiperda, the fall armyworm

NeoBiota ◽  
2018 ◽  
Vol 40 ◽  
pp. 25-50 ◽  
Author(s):  
Regan Early ◽  
Pablo González-Moreno ◽  
Sean T. Murphy ◽  
Roger Day
Keyword(s):  
Fall Armyworm ◽  
Maize Yield ◽  
Sub Saharan Africa ◽  
Potential Range ◽  
Wet Season ◽  
Distribution Models ◽  
Climate Conditions ◽  
Temperature And Precipitation ◽  
Sub Saharan ◽  
Transportation Routes

Fall armyworm, Spodopterafrugiperda, is a crop pest native to the Americas, which has invaded and spread throughout sub-Saharan Africa within two years. Recent estimates of 20–50% maize yield loss in Africa suggest severe impact on livelihoods. Fall armyworm is still infilling its potential range in Africa and could spread to other continents. In order to understand fall armyworm’s year-round, global, potential distribution, we used evidence of the effects of temperature and precipitation on fall armyworm life-history, combined with data on native and African distributions to construct Species Distribution Models (SDMs). We also investigated the strength of trade and transportation pathways that could carry fall armyworm beyond Africa. Up till now, fall armyworm has only invaded areas that have a climate similar to the native distribution, validating the use of climatic SDMs. The strongest climatic limits on fall armyworm’s year-round distribution are the coldest annual temperature and the amount of rain in the wet season. Much of sub-Saharan Africa can host year-round fall armyworm populations, but the likelihoods of colonising North Africa and seasonal migrations into Europe are hard to predict. South and Southeast Asia and Australia have climate conditions that would permit fall armyworm to invade. Current trade and transportation routes reveal Australia, China, India, Indonesia, Malaysia, Philippines and Thailand face high threat of fall armyworm invasions originating from Africa.

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