Évaluation de la potabilité chimique des eaux souterraines dans un bassin versant tropical :Cas du Sud-Ouest de la Côte d’Ivoire

L'etude propose un etat des lieux de la qualite chimique des eaux souterraines ainsi que leur situation vis-a-vis d'elements toxiques d'origine anthropique (nitrate et pesticides) dans la nouvelle boucle du cacao (Sud-Ouest de la Cote dfIvoire). Cinquante-six echantillons dfeau souterraine et de surface ont ete preleves au cours de deux campagnes de terrain puis analyses en se basant sur seize parametres physico-chimiques. Les resultats montrent que les eaux souterraines ont pour la majorite un pH neutre. Elles sont a 34% tres faiblement mineralisees ; seulement 21% presente une conductivite superieure a 500 ƒÊS.cm-1. Ces eaux sont pour la plupart bicarbonatees dont une moitie est alcaline et lfautre calco-magnesienne. La qualite chimique est satisfaisante pour 80% des eaux etudiees au regard des normes OMS. Certaines ont meme des teneurs voisines a certaines eaux minerales de commerce. En revanche, dfautres presentent des teneurs tres critiques en nitrate, en sulfate et en fer. Les fortes teneurs en nitrate proviennent des activites humaines demontrant que les ressources en eau de la region ne sont pas a lfabri dfune pollution par les pesticides qui sont fortement utilises dans les plantations de cacao, cafe, hevea et palmier a huile ainsi que dans les maraichers.Mots cles: Qualite physico-chimique, pesticides, nitrate, hydrochimie, Cote dfIvoire

Parameter estimation methods for analyzing overlapping gravitational wave signals in the third-generation detector era

In the coming years, third-generation detectors such as the EinsteinTelescope and the Cosmic Explorer will enter the network of ground-basedgravitational-wave detectors. Their current design predicts a significantlyimproved sensitivity band with a lower minimum frequency than existingdetectors. This, combined with the increased arm length, leads to two majoreffects: the detection of more signals and the detection of longer signals.Both will result in a large number of overlapping signals. It has been shown that such overlapping signals can lead to biases in therecovered parameters, which would adversely affect the science extracted fromthe observed binary merger signals. In this work, we analyze overlapping binaryblack hole coalescences with two methods to analyze multi-signal observations:hierarchical subtraction and joint parameter estimation. We find that thesemethods enable a reliable parameter extraction in most cases and that jointparameter estimation is usually more precise but comes with highercomputational costs.<br

Application des méthodes statistiques et géostatistiques à l’étude de la conductivité électrique des eaux souterraines de la région du N’zi-Comoé (Centre-Est de la Côte d’Ivoire)

La r&#233;gion du N&#8217;zi-Como&#233; est situ&#233;e au Centre-Est de la C&#244;te d&#8217;Ivoire. L&#8217;approvisionnement en eau potable des populations rurales est assur&#233; majoritairement par les forages d&#8217;hydraulique villageoise. Ces eaux appartiennent &#224; un environnement g&#233;ologique de socle cristallin et cristallophyllien. Les formations g&#233;ologiques sont constitu&#233;es de roches magmatiques (granites, migmatites, gneiss) et m&#233;tamorphiques (schistes, gr&#232;s, roches vertes). La d&#233;termination de la qualit&#233; des eaux souterraines peut &#234;tre appr&#233;ci&#233;e par la conductivit&#233; &#233;lectrique (CE). Elle repr&#233;sente un param&#232;tre physique de l&#8217;eau qui fournit des informations sur sa min&#233;ralisation. Le but de cette &#233;tude est de comprendre l&#8217;environnement physico-chimique et l&#8217;&#233;volution spatiale de la min&#233;ralisation des eaux souterraines des aquif&#232;res fissur&#233;s de la r&#233;gion du N&#8217;zi-Como&#233; &#224; partir d&#8217;un descripteur performant qui est la conductivit&#233; &#233;lectrique (CE). La m&#233;thodologie appliqu&#233;e est fond&#233;e sur une approche pluridisciplinaire int&#233;grant les analyses statistiques et g&#233;ostatistiques, avec un &#233;chantillon de 193 forages. L&#8217;analyse en composantes principales norm&#233;es (ACPN) a confirm&#233; que la conductivit&#233; &#233;lectrique des eaux souterraines est influenc&#233;e par les param&#232;tres physico-chimiques de l&#8217;eau. Cependant, elle n&#8217;est pas influenc&#233;e par l&#8217;&#233;paisseur d&#8217;alt&#233;ration et l&#8217;&#233;paisseur for&#233;e dans le niveau fissur&#233;. L&#8217;analyse g&#233;ostatistique a montr&#233; que le mod&#232;le exponentiel mod&#233;lise au mieux la conductivit&#233; &#233;lectrique, variable r&#233;gionalis&#233;e et structur&#233;e. La cartographie de la conductivit&#233; &#233;lectrique, en tenant compte de sa structure spatiale, a permis de mettre en &#233;vidence une r&#233;partition h&#233;t&#233;rog&#232;ne dans l&#8217;espace de la min&#233;ralisation avec les plus fortes valeurs dans le Sud-Ouest et le Nord-Est.Mots cl&#233;s: Min&#233;ralisation; ACPN; Analyse variographique; Cartographie; Aquif&#232;res fissur&#233;s; C&#244;te d&#8217;Ivoir

Bichat guidelines for the clinical management of brucellosis and bioterrorism-related brucellosis

Interest in Brucella species as a biological weapon stems from the fact that airborne transmission of the agent is possible. It is highly contagious and enters through mucous membranes such as the conjunctiva, oropharynx, respiratory tract and skin abrasions. It has been estimated that 10-100 organisms only are sufficient to constitute an infectious aerosol dose for humans. Signs and symptoms are similar in patients whatever the route of transmission and are mostly non-specific. Symptoms of patients infected by aerosol are indistinguishable from those of patients infected by other routes. Regimens containing doxycycline plus streptomycin or doxycycline plus rifampin are effective for most forms of brucellosis. Isolation of patients is not necessary. Trimethoprim-sulfamethoxazole and fluoroquinolones also have good results against Brucella, but are associated with high relapse rates when used as monotherapy. The combination of ofloxacin plus rifampicin is associated with good results. Even if there is little evidence to support its utility for post-exposure prophylaxis, doxycycline plus rifampicin is recommended for 3 to 6 weeks

Bichat guidelines for the clinical management of brucellosis and bioterrorism-related brucellosis

Interest in Brucella species as a biological weapon stems from the fact that airborne transmission of the agent is possible. It is highly contagious and enters through mucous membranes such as the conjunctiva, oropharynx, respiratory tract and skin abrasions. It has been estimated that 10-100 organisms only are sufficient to constitute an infectious aerosol dose for humans. Signs and symptoms are similar in patients whatever the route of transmission and are mostly non-specific. Symptoms of patients infected by aerosol are indistinguishable from those of patients infected by other routes. Regimens containing doxycycline plus streptomycin or doxycycline plus rifampin are effective for most forms of brucellosis. Isolation of patients is not necessary. Trimethoprim-sulfamethoxazole and fluoroquinolones also have good results against Brucella, but are associated with high relapse rates when used as monotherapy. The combination of ofloxacin plus rifampicin is associated with good results. Even if there is little evidence to support its utility for post-exposure prophylaxis, doxycycline plus rifampicin is recommended for 3 to 6 weeks

The role of menaquinones (vitamin K2) in human health

Recent reports have attributed the potential health benefits of vitamin K beyond its function to activate hepatic coagulation factors. Moreover, several studies have suggested that menaquinones, also known as vitamin K2, may be more effective in activating extra-hepatic vitamin K-dependent proteins than phylloquinone, also known as vitamin K1. Nevertheless, present dietary reference values (DRV) for vitamin K are exclusively based on phylloquinone, and its function in coagulation. The present review describes the current knowledge on menaquinones based on the following criteria for setting DRV: optimal dietary intake; nutrient amount required to prevent deficiency, maintain optimal body stores and/or prevent chronic disease; factors influencing requirements such as absorption, metabolism, age and sex. Dietary intake of menaquinones accounts for up to 25% of total vitamin K intake and contributes to the biological functions of vitamin K. However, menaquinones are different from phylloquinone with respect to their chemical structure and pharmacokinetics, which affects bioavailability, metabolism and perhaps impact on health outcomes. There are significant gaps in the current knowledge on menaquinones based on the criteria for setting DRV. Therefore, we conclude that further investigations are needed to establish how differences among the vitamin K forms may influence tissue specificities and their role in human health. However, there is merit for considering both menaquinones and phylloquinone when developing future recommendations for vitamin K intak

Incorporating prior knowledge improves detection of differences in bacterial growth rate

BACKGROUND: Robust statistical detection of differences in the bacterial growth rate can be challenging, particularly when dealing with small differences or noisy data. The Bayesian approach provides a consistent framework for inferring model parameters and comparing hypotheses. The method captures the full uncertainty of parameter values, whilst making effective use of prior knowledge about a given system to improve estimation. RESULTS: We demonstrated the application of Bayesian analysis to bacterial growth curve comparison. Following extensive testing of the method, the analysis was applied to the large dataset of bacterial responses which are freely available at the web-resource, ComBase. Detection was found to be improved by using prior knowledge from clusters of previously analysed experimental results at similar environmental conditions. A comparison was also made to a more traditional statistical testing method, the F-test, and Bayesian analysis was found to perform more conclusively and to be capable of attributing significance to more subtle differences in growth rate. CONCLUSIONS: We have demonstrated that by making use of existing experimental knowledge, it is possible to significantly improve detection of differences in bacterial growth rate

Drug Eluding Stents for Malignant Airway Obstruction: A Critical Review of the Literature

Lung cancer being the most prevalent malignancy in men and the 3rd most frequent in women is still associated with dismal prognosis due to advanced disease at the time of diagnosis. Novel targeted therapies are already on the market and several others are under investigation. However non-specific cytotoxic agents still remain the cornerstone of treatment for many patients. Central airways stenosis or obstruction may often complicate and decrease quality of life and survival of these patients. Interventional pulmonology modalities (mainly debulking and stent placement) can alleviate symptoms related to airways stenosis and improve the quality of life of patients. Mitomycin C and sirolimus have been observed to assist a successful stent placement by reducing granuloma tissue formation. Additionally, these drugs enhance the normal tissue ability against cancer cell infiltration. In this mini review we will concentrate on mitomycin C and sirolimus and their use in stent placement