Analyses protéomiques d'une communauté bactérienne du sol et de Rhodanobacter thiooxydans se développant en présence de subérine de pomme de terre

Résumé: La subérine, un polymère lipidique et complexe des plantes est retrouvé dans divers tissus dont le périderme de la pomme de terre. Le processus biologique de sa dégradation reste encore peu connu et est attribué aux champignons. Des échantillons de sol provenant d'un champ de pommes de terre ont été inoculés dans un milieu de culture contenant de la subérine comme source de carbone. Une approche métaprotéomique a été utilisée pour identifier les populations bactériennes qui se développent en présence de la subérine sur une période d'incubation de 60 jours. Le nombre de spectres normalisé (NSpC) des protéines extracellulaires produites par la communauté bactérienne du sol ont considérablement diminué du jour 5 au jour 20, puis ont augmenté lentement, révélant une succession de bactéries, où la population des bactéries du genre Pseudomonas à croissance rapide a diminué et a été remplacée par d’autres espèces bactériennes qui pouvaient se développer en présence de la subérine. La récalcitrance de la subérine a été démontrée par l'émergence de bactéries auxotrophes telles qu’Oscillatoria dans les derniers jours de la culture bactérienne. Néanmoins, l'identification de deux lipases dans le surnageant de la culture suggère qu'au moins certaines espèces bactériennes peuvent dégrader la subérine. Une des lipases (I4WGM2) a été associée à Rhodanobacter thiooxydans. Lorsque cultivée dans un milieu contenant de la subérine, la souche de R. thiooxidans LCS2 a produit trois lipases, dont I4WGM2. R. thiooxidans LCS2 a également produit d'autres protéines liées au métabolisme des lipides, des transporteurs de chaines d’acide gras et les enzymes de la [béta]-oxydation. Ceci suggère que R. thiooxydans pourrait participer à la dégradation de la subérine.Abstract: Suberin is a complex lipidic plant polymer found in various tissues including potato periderm. The biological degradation process of suberin is poorly characterized and is attributed to fungi. Soil samples from a potato field were used to inoculate a culture medium containing suberin as carbon source and a metaproteomics approach was used to identify bacterial populations that develop in the presence of suberin, over a 60-day incubation period. The normalized spectral counts of predicted extracellular proteins produced by the soil bacterial community drastically decreased from day 5 to day 20 and then slowly increased, revealing a succession of bacteria. The population of fast-growing pseudomonads declined and was replaced by species that could develop in the presence of suberin. The recalcitrance of suberin was demonstrated by the emergence of auxotrophic bacteria such as Oscillatoria in the last days of the assay. Nevertheless, the identification of two putative lipases in the culture supernatants suggests that at least some bacterial species could degrade suberin. One of the lipases (I4WGM2) was associated with Rhodanobacter thiooxydans. When grown in a suberin-containing medium, R. thiooxydans strain LCS2 produced three lipases, including I4WGM2. This strain also produced other proteins linked to lipid metabolism, including fatty acid and lipid transporters and [beta]-oxidation enzymes, suggesting that R. thiooxydans could participate in suberin degradation

Evaluation du Potentiel Energétique de Biogaz des Déjections Animales de la Région Administrative de Kankan (République de Guinée)

Résumé - Depuis toujours, l'homme a organisé son espace de vie à proximité des élevages d'animaux. Néanmoins, la croissance démographique et la salubrité due aux déjections de ces animaux  ont motivées les travaux de valorisation des déchets animaux. La présente étude s’inscrit dans cette logique, qui consiste à faire l’évaluation du potentiel énergétique de biogaz des déjections animales de la région de Kankan. Les résultats obtenus portent sur : les quantités de déjections journalières moyennes de déjetions : bouses de vaches (4,45 kg) et fientes de poules (0,015 kg). Les effectifs du cheptel animal sont : bovins (1572132) ; Ovins (452373) ; caprins (385551) et volailles (321644). Le plus grand effectif de bétail est enregistré dans la préfecture de Siguiri (372411), suivi respectivement des préfectures de Kérouané, Mandiana, Kouroussa et Kankan. Les potentiels du biogaz de bouses de vaches par préfecture sont les suivants : Siguiri (180419,732 m3/j), Kérouané (167063,059 m3/j), Mandiana (158159,094 m3/j), Kouroussa (142498,795 m3/j) et Kankan (113500,716 m3/j). Pour les volailles on a : Siguiri (605,207 m3/j), Kérouané (577,065 m3/j), Mandiana (124,067 m3/j), Kouroussa (4,805 m3/j) et Kankan (635,467 m3/j).  De même, le plus grand potentiel énergétique est enregistré à Siguiri soit (829094,218 kWh/j), suivi respectivement de Kérouané (767791,764 m3/j), Mandiana (724 936,880 kWh/j), Kouroussa (652666,488 kWh/j), et Kankan (522743,719kWh/j). Le Potentiel total journalier énergétique de biogaz de la région est 3497233,069 kWh/j, avec une production annuelle de 12590039,048 MWh. Les résultats obtenus au cours de ce travail sont une première estimation du potentiel énergétique de biogaz des déjections animales de la région de Kankan.Abstract - Man has always organized his living space near animal farms. Nevertheless, the population growth and the healthiness due to the droppings of these animals have motivated work on the recovery of animal waste. This study is part of this logic, which consists in evaluating the energy potential of biogas in animal waste from the Kankan region. The results obtained relate to: the quantities of average daily droppings of droppings: cow dung (4.45 kg) and chicken droppings (0.015 kg). The numbers of animal livestock are: cattle (1572132) ; sheep (452373) ; goats (385551) and poultry (321644). The largest number of livestock is recorded in the prefecture of Siguiri (372411), followed respectively by the prefectures of Kérouané, Mandiana, Kouroussa and Kankan. The cow dung biogas potentials by prefecture are as follows: Siguiri (180419.732 m3/d), Kérouané (167,063.059 m3/d), Mandiana (158159.094 m3/d), Kouroussa (142498.795 m3/d) and Kankan (113,500.716 m3/d). For poultry, we have: Siguiri (605.207 m3/d), Kérouané (577.065 m3/d), Mandiana (124.067 m3/d), Kouroussa (4.805 m3/d) and Kankan (635.467 m3/d). Similarly, the greatest energy potential is recorded in Siguiri (829,094.218 kWh/d), followed respectively by Kérouané (767791.764 m3/d), Mandiana (724936.880 kWh/d), Kouroussa (652666.488 kWh/d) and Kankan (522743.719 kWh/d). The total daily energy potential of biogas in the region is 3497233.069 kWh/d, with an annual production of 12590039.048 MWh. The results obtained during this work are a first estimate of the biogas energy potential of animal waste in the Kankan region.Keywords - Potential, biogas, energy, manure, animal, Kankan

Perception de la Dégradation des Terres et Adoption des Technologies de Conservation des Eaux et des Sols au Nord du Burkina Faso : le cas du Zaï et des Cordons Pierreux

This study is based on data collected from 141 family-type farms in the Yatenga province in Burkina Faso. A probit approach is used to analyze the effect of perception of land degradation and other factors on the adoption of zaï and stone rows. The results of the estimation show that the availability of organic matter from small ruminants is determinant for the adoption of both zaï and stone rows. Although most of farmers are aware of the causes and consequences of land degradation, this factor does not significantly impact on farmers’ decision to invest in SWC measures. Opportunities do exist for making more efficient use of local sources of nutrients, such as small ruminants’ organic matter in combination with locally accepted SWC measures. This may increase farmers’ willingness to go beyond SWC measures, to invest in nutrient supply in their soils which are characterized by poor fertility. The study shows that combining training on SWC and the development of small-scale animal breeding could contribute to reach this goal in a degraded area.Land degradation, technology adoption, stone rows, Zai, Yatenga, Community/Rural/Urban Development, Consumer/Household Economics, Environmental Economics and Policy, Food Consumption/Nutrition/Food Safety, Food Security and Poverty, Labor and Human Capital, Land Economics/Use, Marketing, Research and Development/Tech Change/Emerging Technologies,

Optimal Maintenance Policy for Second-Hand Equipments under Uncertainty

This chapter addresses a maintenance optimization problem for re-manufactured equipments that will be reintroduced into the market as second-hand equipments. The main difference of this work and the previous literature on the maintenance optimization of second-hand equipments is the influence of the uncertainties due to the indirect obsolescence concept. The uncertainty is herein about the spare parts availability to perform some maintenance actions on equipment due to technology vanishing. The maintenance policy involves in fact a minimal repair at failure and a preventive repair after some operating period. To deal with this shortcoming, the life cycle of technology or spare parts availability is defined and modeled as a random variable whose lifetimes distribution is well known and Weibull distributed. Accordingly, an optimal maintenance policy is discussed and derived for such equipment in order to overcome the uncertainty on reparation action. Moreover, experiments are then conducted and different life cycle of technologies are evaluated according to their obsolescence processes (accidental or progressive vanishing) on the optimal operating condition

Anesthesie au cours des ventriculocisternostomies au Mali : Une serie de 31 cas

Introduction La ventriculocisternostomie est une technique moderne du traitement des hydrocéphalies. Elle est peu fréquente en Afrique. Objectif:  Décrire la prise en charge anesthésique et l’évolution des patients opérés par ventriculocisternostomie. Patients et Méthode: Etude de cohorte prospective de 15 mois de janvier 2014 au 31 mars 2015. La saisie et l’analyse des données ont été effectuées par Microsoft word 2010 Epi info 3.5.3.fr. Résultats:  Les nourrissons prédominaient avec un sexe ratio de 1,81 en faveur du sexe masculin. Un antécédent de méningite ou d’infection respiratoire à répétition a été retrouvé chez 10 patients (32,2%). L’indication de la ventriculocisternostomie était une hydrocéphalie chez 30 patients (96, 8%). La classe ASA était II chez 19 patients (61,3%). L’intubation était prévue difficile chez 28 patients (90,3%).Tous les patients ont été opérés sous anesthésie générale. Une antibioprophylaxie a été faite chez tous les patients. La tachycardie isolée a été le seul évènement indésirable per opératoire observé chez 13 patients (41,9%). La durée de la chirurgie était de 62, 25 ± 20,9 minutes celle de l’anesthésie était de 93,5 ± 25,4 minutes. En postopératoire, une complication a été observée chez 7 patients (22,6%). Il s’agissait d’une méningite chez 3 patients (42,9%), d’une souffrance cérébrale, d’une obstruction de la stomie, d’un abcès cérébral et une paralysie du nerf III dans 14,3% chacune (1 patient). L’évolution était favorable chez 29 patients (93,5%). La durée médiane d’hospitalisation était de 3 jours. Conclusion:  Au Mali, la prise en charge anesthésique au cours de la ventriculocisternostomie s’adresse à une population pédiatrique avec un terrain précaire.   English title: Anesthesia during endoscopic third ventriculostomy in Mali: A series of 31 cases Introduction: Endoscopic Third Ventriculostomy (ETV) is a modern technique for the treatment of hydrocephalus. It is uncommon in Africa. Objective To describe ananesthesic management and the outcome of patients operated on by ETV. Patients and Methods Prospective cohort study over 15 months to January 2014 at 31 march 2015. The data entry and analysis were done by word office, Epi info 3.5.3.fr. Results: Infants predominated with a sex ratio of 1.81 in favor of men. A history of meningitis or recurrent respiratory infection was found in 10 patients (32.2%). The indication of ETV was hydrocephalus in 30 patients (96.8%). The ASA class was II in 19 patients (61.3%).  Intubation was expected to be difficult in 28 patients (90.3%). All patients were operated on under general anesthesia. Antibiotic  prophylaxis was done in all patients. Isolated tachycardia was the only peroperative adverse event observed in 13 patients (41.9%). The duration of the surgery was 62.25 ± 20.9 minutes that of the anesthesia was 93.5 ± 25.4 minutes. Postoperatively, a complication was observed in 7 patients (22.6%). It was meningitis in 3 patients (42.9%), brain pain, obstruction of the stoma, brain abscess and nerve III paralysis in 14.3% each (1 patient). The outcome was favorable in 29 patients (93.5%). The median hospital stay was 3 days. Conclusion:  In Mali, anesthetic management during ETV is aimed at a pediatric population with precarious terrain

Etude des connaissances, des attitudes, et des pratiques des Chirurgiens-dentistes exerçant au Mali, sur la radioprotection.

The use of ionizing radiation (IR) for medical purposes, the main artificial source of exposure, can be responsible for long-term stochastic effects in practitioners and patients. The objective of this study was to evaluate the knowledge, attitudes, and practices of dental surgeons practicing in Mali, in terms of radiation protection. A self-administered questionnaire designed on Googleforms was sent via Whatsapp to practitioners. The main items explored were: knowledge of radiation protection institutions, use of radiation protection devices, knowledge of the most exposed organs, risks of exposure to ionizing radiation, and application of radiation protection measures during radiographic examinations of children and pregnant women. The data were exported and analyzed using SPSS 20.0 software. The level of significance was set at p≤0.05.Of 123 questionnaires sent, 51 were completely filled out, for a response rate of 41.46%. Nearly 70% (60.8%) of the practitioners were unaware of the existence of any regulatory authority for radiation protection. The thyroid was considered the organ most exposed to ionizing radiation by 33.3% of practitioners. Only 31.4% of practitioners reported having a radiation protection device in their facility. Among practitioners who performed radiographic examinations themselves, 46.15% did not use any radiation protection equipment during examinations of children and pregnant women. There is a real need to strengthen the capacity of dentists practicing in Mali in the area of radiation protection through the introduction of continuing education on the subject.      L’utilisation médicale des rayonnements ionisants (RI) peut être responsable d’effets stochastiques à long terme chez les praticiens et les patients. L’objectif de cette étude était, d’évaluer les connaissances, attitudes, et pratiques des Chirurgiens-dentistes exerçant au Mali, en matière de radioprotection.Un questionnaire auto-admi­nistré conçu sur Google Forms a été envoyé aux praticiens. Les principaux items explorés étaient : la connaissance des institutions de radioprotection, l’usage des dispositifs de radioprotection, la connaissance des organes les plus exposés, des  risques de l’exposition aux rayonnements ionisants et l’application des mesures de radioprotection lors des examens radiographiques chez les enfants et les femmes enceintes. Les données ont été  exportées et analysées à l’aide du lo­giciel SPSS 20.0. Le niveau de significativité est fixé à p≤0,05.Sur 123 questionnaires envoyés, 51 ont été complètement renseignés soit un taux de réponse de 41,46 %. Près de 70% (60,8%) des praticiens ignoraient l’existence de tout organisme de règlementation en matière de radioprotection. La thyroïde était considérée comme l’organe le plus exposé aux rayonnements ionisants par 33,3%  des praticiens. Seuls 31,4% des praticiens déclaraient avoir un dis­positif de radioprotection dans leur structure. Parmi les praticiens réalisant eux-mêmes les examens radiographiques, 46,15% n’utilisaient aucun moyen de radioprotection lors des examens chez l’enfant et les femmes enceintes. Il existe un réel besoin de renforcement des capacités des chirurgiens-dentistes exerçant au Mali en matière de radioprotection à travers l’instauration d’une formation continue sur le sujet

PROBING VIBRATIONAL WAVE PACKETS IN ORGANOPHOSHOROUS MOLECULES USING FEMTOSECOND TIME-RESOLVED MASS SPECTROMETRY

Organic phosphates and phosphonates share a basic structure with organophoshorous chemical warfare agents and cellular components such as DNA. To understand ultrafast nuclear dynamics in isolated organic phosphates and phosphonates, Femtosecond Time Resolved Mass Spectrometry (FTRMS) was employed. FTRMS applies the pump-probe technique with mass spectrometric detection. In our experiment an ionizing $10^{14}$ W cm$^{-2}$, 1500 nm, 18 fs pump and a non-ionizing $10^{13}$ W cm$^{-2}$, 800 nm, 25 fs probe pulse were used. Experiments were performed on four related compounds: dimethyl methylphosphonate (DMMP), diethyl methylphosphonate (DEMP), diisopropyl methylphosphonate (DIMP) and trimethyl phosphate (TMP). The yields of parent molecular ions generated by the pump pulse exhibited ultrafast oscillations with the period depending on the parent molecule. These oscillations indicate the presence of a vibrational wave packet that is excited upon ionization. In DMMP, a well resolved peak of 45 fs ($732\pm28$ cm$^{-1}$) was observed with a weak feature at 610-650 cm$^{-1}$, while DIMP exhibits bimodal oscillation with frequencies of $554\pm28$ and 670-720 cm$^{-1}$. Oscillations for DEMP were barely visible due to rapid decay. The high- and low- frequency oscillations in DMMP and DIMP were assigned to coherent excitation of O-P-O bend and P-C stretching respectively based on DFT calculations. Bimodal oscillations at 770 and 880 cm$^{-1}$ in TMP were also observed and are tentatively assigned to the symmetric and asymmetric P-O stretching modes. These results suggest that this group of compounds exhibits similar coherent vibrational excitation upon ionization. These results may have applications to development of new organophosphorous chemical warfare agent detection and destruction techniques based on the coherent control and may point to reaction pathways in organophosphorous compounds of biological relevance

Etude des connaissances, des attitudes, et des pratiques des Chirurgiens-dentistes exerçant au Mali, sur la radioprotection.

The use of ionizing radiation (IR) for medical purposes, the main artificial source of exposure, can be responsible for long-term stochastic effects in practitioners and patients. The objective of this study was to evaluate the knowledge, attitudes, and practices of dental surgeons practicing in Mali, in terms of radiation protection. A self-administered questionnaire designed on Googleforms was sent via Whatsapp to practitioners. The main items explored were: knowledge of radiation protection institutions, use of radiation protection devices, knowledge of the most exposed organs, risks of exposure to ionizing radiation, and application of radiation protection measures during radiographic examinations of children and pregnant women. The data were exported and analyzed using SPSS 20.0 software. The level of significance was set at p≤0.05.Of 123 questionnaires sent, 51 were completely filled out, for a response rate of 41.46%. Nearly 70% (60.8%) of the practitioners were unaware of the existence of any regulatory authority for radiation protection. The thyroid was considered the organ most exposed to ionizing radiation by 33.3% of practitioners. Only 31.4% of practitioners reported having a radiation protection device in their facility. Among practitioners who performed radiographic examinations themselves, 46.15% did not use any radiation protection equipment during examinations of children and pregnant women. There is a real need to strengthen the capacity of dentists practicing in Mali in the area of radiation protection through the introduction of continuing education on the subject.      L’utilisation médicale des rayonnements ionisants (RI) peut être responsable d’effets stochastiques à long terme chez les praticiens et les patients. L’objectif de cette étude était, d’évaluer les connaissances, attitudes, et pratiques des Chirurgiens-dentistes exerçant au Mali, en matière de radioprotection.Un questionnaire auto-admi­nistré conçu sur Google Forms a été envoyé aux praticiens. Les principaux items explorés étaient : la connaissance des institutions de radioprotection, l’usage des dispositifs de radioprotection, la connaissance des organes les plus exposés, des  risques de l’exposition aux rayonnements ionisants et l’application des mesures de radioprotection lors des examens radiographiques chez les enfants et les femmes enceintes. Les données ont été  exportées et analysées à l’aide du lo­giciel SPSS 20.0. Le niveau de significativité est fixé à p≤0,05.Sur 123 questionnaires envoyés, 51 ont été complètement renseignés soit un taux de réponse de 41,46 %. Près de 70% (60,8%) des praticiens ignoraient l’existence de tout organisme de règlementation en matière de radioprotection. La thyroïde était considérée comme l’organe le plus exposé aux rayonnements ionisants par 33,3%  des praticiens. Seuls 31,4% des praticiens déclaraient avoir un dis­positif de radioprotection dans leur structure. Parmi les praticiens réalisant eux-mêmes les examens radiographiques, 46,15% n’utilisaient aucun moyen de radioprotection lors des examens chez l’enfant et les femmes enceintes. Il existe un réel besoin de renforcement des capacités des chirurgiens-dentistes exerçant au Mali en matière de radioprotection à travers l’instauration d’une formation continue sur le sujet

Meeting the sexual health needs of men who have sex with men in Senegal

A study conducted in Dakar, Senegal by researchers from the National AIDS Council, Cheikh Anta Diop University, and the Horizons program obtained information on the needs, behaviors, knowledge, and attitudes of men who have sex with men (MSM). This study offers important insights into the sexuality of MSM, their vulnerability to STI/HIV, and the role of violence and stigma in their lives. The results also highlight the lack of sexual health services and information available to cover the specific needs of MSM. The results of this study were summarized during a meeting held in April 2001 in Dakar and raised awareness of the importance for public health of developing non-stigmatizing interventions for MSM. The results led to the establishment of an NGO pool to develop and coordinate activities for MSM in Dakar

When adaptation barriers and enablers intersect : key considerations for adaptation planning drawn from ASSAR's findings

The work of Adaptation at Scale in Semi-Arid Regions (ASSAR) highlights the existence of barriers and enablers of adaptation, including their interacting effects. Factors do not operate in isolation. This document summarises examples from studies in semi-arid regions of India, Namibia, Ethiopia and Mali to illustrate how barriers and enablers interact, and to draw out key considerations for planning how to facilitate an enabling environment for adaptation. ASSAR uses Transformative Scenario Planning and Vulnerability and Risk Assessment as ways for bringing people together to address intersecting barriers and participate in adaptation planning.UK Government’s Department for International Development (DfID)International Development Research Centre (IDRC