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The waters off the coast of Senegal have been stripped of their false cods, also known as "thiof" or groupers. How is it possible that this country's iconic fish is nearly extinct? A French-Senegalese team recently demonstrated that the collapse of stocks is due to the boom in the small-scale fishery sector – generally viewed as a sustainable alternative to industrial fisheries. Over 30 years, the number of pirogues has quadrupled. Technological progress continuously improves the fishing power of the fleet. In order to reduce pressure on the resource, researchers recommend the implementation of a management system to control small-scale fisheries and regulate exportation, which pushes up prices per kilo and makes thiof a very profitable commodity, despite the scarcity of the fish.
In Africa, more than 25 million people, most of them women, are currently infected by the AIDS virus. However, a study conducted by Epicentre( 1) and IRD researchers shows that men are less responsive to treatment. The provision of healthcare is intended to restore the level of lymphocyte cells, called T-CD4, reduced by HIV. Based on 13,000 patients monitored through four programmes carried out by Médecins sans frontières France in Malawi, Uganda and Kenya, the study shows that the reconstitution of these white blood cells is slower in men than in women.
Due to stigmatisation and work- and transport-related constraints, among others, men often receive healthcare at a later stage and are less responsive to treatment. However, this gender-based difference could also stem from biological causes, such as physiologically lower rates of T-CD4 lymphocytes.
This study underlines the fact that men should therefore receive special attention from programmes aimed at fighting the disease.
In 2005, there were more than 5,000 marine protected areas across the globe. These reserves assist in preserving biodiversity. And yet, the impact on fishing has not yet been demonstrated. The Amphore( 1) programme, coordinated by the IRD and involving French and West African laboratories, provides a detailed economic and biological survey. Four reserves of varying size and age were studied in closer detail, including two in West Africa: one in Senegal, the other in Mauritania. A ban on fishing operations within protected areas only gives rise to a small increase in the total fish biomass, although there is an improvement in population diversity. The observations and models carried out by researchers show that halieutic resources are greater outside of protected areas, in zones that can be exploited by fishermen. The larger the area of the reserve, the more positive the effect. However, the creation of vast protected areas can cause problems, particularly in heavily anthropized areas, and requires participatory management.
The rate of primary education across the world has increased remarkably during the last decade, rising from 82% in 1999 to 88% in 2008, according to Unesco. The countries with the lowest education rates, in Sub-Saharan Africa and Western Asia, are also those who have demonstrated the largest increases. Beyond these figures, researchers have been questioning the reality in terms of inequalities and their reduction, and have shown that they have not yet disappeared. Two studies in Dakar have demonstrated this. They have provided a clearer picture of the consequences of the changes observed in Senegal, where an increasing number of girls are starting school, but remain less likely to proceed to secondary education than boys. The research has also underlined the boom in private education, now closing the gap with public schools: this is particularly the case for denominational private schools, with a success rate of almost 90% for the end-of-primary certificate, as opposed to just over 50% in the public sector.
The democratisation of primary schools has ushered in new educational norms and does not necessarily mean equal opportunities.
Potential treasures lie concealed under the West African savannah in some of the Earth’s poorest countries. Extensive gold fields occur, over hundreds of kilometres, from Senegal to Niger. The rapid rise in precious metal prices over the past five years has prompted hugely intensified mineral exploration. Yet new veins must be found if this African gold rush is to continue.
A new discovery, published in Nature Geoscience , is now shaking up our understanding of the Earth and the prospects for exploration. The research team ( 4), led by an IRD geologist, used innovatory modelling software to take a fresh look at the origins of plate tectonics in the light of the geothermal history of the gold deposits in the West African gold fields. These investigations will lead to better ways of locating the emplacement of veins and their depth. This result is a fundamental one for the science which furthermore offers promising applications for West African countries.