Your selection in the media library
Page 1 : Results 1 to 5 on 9
Will we soon be forced to eat jellyfish? Since the beginning of the 2000s, these gelatinous creatures have invaded many of the world's seas, like the Japan Sea, the Black Sea, the Mediterranean Sea, etc. Is it a cyclic phenomenon, caused by changes in marine currents or even global warming? Until now, the causes remained unknown. A new study conducted by IRD researchers and its partners, published in Bulletin of marine science, exposes overfishing as the main factor.
Some good news in the world of climate research: the “Agulhas Current” off the coast of South Africa, is said to stimulate North-South ocean circulation in the Atlantic. This “conveyor belt” which redistributes and controls heat around the globe, is threatening to slow down due to melting ice. As has been shown in a recent study however, published in Nature Climate Change ( 1) based on satellite altimeter measurements, this famous current is accelerating. Located at the interface between the Indian and Atlantic Oceans, this current multiplies injections of warm and above all highly salt water into the Atlantic from the Indian Ocean. The phenomenon, also caused by global warming, could in return be offsetting the effects of glacial melting on thermohaline circulation( 2) and the global climate. More locally, it will considerably change the climate in southern Africa.
One and a half million people per year are poisoned by snake venom in Sub-Saharan Africa. An IRD researcher recently analysed around 100 surveys and medical reports published over the past 40 years. No large-scale study of the situation had hitherto been conducted and public health authorities had underestimated the size of the problem. This means that currently only 10% of victims are treated, owing to a shortage of antivenoms * and lack of awareness among health care practitioners. Yet the clinical complications can be very serious, even fatal. A bite from a cobra or mamba can bring on death by asphyxia –due to respiratory paralysis– within 6h after the incident. Venom injected by the ocellated carpet viper, common in the African savannah, can cause haemorrhages leading to the victim’s death in a few days.
This new study provides authorities with more detailed and reliable figures which should enable them to readjust their health-care services in better tune with needs.
Rice is the world’s most commonly used cereal food, feeding half of humanity. However, rice production will have to double within 20 years from now to meet the needs of a growing population.
Two species are used for cultivation, one Asian and the other African. The Asian species gives much stronger agronomic performances, but the African one is more rustic, more resistant to pathogens, more tolerant to drought and soil salinity.
With the aim of transferring these properties to Asian rice, IRD scientists and their research partners( 1) are seeking to overcome the sterility between the two species( 2). They used genome sequencing to compare the structure of a portion of chromosome, identified as the factor behind the reproductive barrier. These investigations, the first results of which were published recently in the journal PLoS One , have led to the definition of genetic markers allowing more rapid development of fertile lineages of improved Asian rice.
Every day, 1500 young infants in the world contract HIV from their mother. Ninety per cent of them live in Sub-Saharan Africa. Infection occurs in utero or during delivery, or later during breastfeeding. Young mothers could abandon breastfeeding, but this would deprive their baby of an essential source of nutrients and antibodies and, if artificial milk was used, expose the child to other illnesses (such as diarrhoea owing to lack of safe drinking water, or malnutrition).
Now they can breastfeed with less risk. An international consortium of researchers, including a team from the IRD( 1), recently showed that by taking an antiretroviral treatment up to the sixth month of breastfeeding mothers can halve the probability of contaminating their child in comparison with standard treatment recommended in the previous WHO (World Health Organization) protocol guidelines( 2). This new approach reduces the risk of HIV transmission from 9.5 to 5.4%. These highly encouraging results prompted WHO to revise their guidelines on prophylaxis during breastfeeding.