309 research outputs found

    Evaluation des traits de vie d'une espèce endémique du Maroc (Salmo trutta macrostigma, Dumeril, 1858) dans une rivière du Moyen Atlas du Maroc: Oued Sidi Rachid

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    Cette étude a pour objectif la contribution à la détermination de la qualité physicochimique des eaux de l'Oued Sidi Rachid au Moyen Atlas où vit une espèce endémique du Maroc : la truite de rivière (Salmo trutta macrostigma, Duméril, 1858). L'étude des paramètres essentiels pour la vie de ce salmonidé au cours de la période comprise entre le mois de mai 2007 et le mois d'avril 2008 montre que la température, le potentiel Hydrogène (pH) et les concentrations des nitrites témoignent de la bonne qualité des eaux de l'Oued Sidi Rachid et permettent de classer ce site parmi les sites à vocation salmonicole. Les concentrations des orthophosphates sont très faibles et ne témoignent d'aucune source de pollution organique. Les concentrations des indicateurs de la dureté reflètent la nature géologique (carbonatée) de la région. Les résultats obtenus montrent bien que les eaux de l'Oued Sidi Rachid assurent à la truite de rivière un bon habitat écologique favorable à son développement et à sa reproduction.Mots clés: Qualité physicochimique, Truite de rivière, Oued Sidi Rachid, Maro

    Contribution a l’étude physicochimique de l’écosystème lacustre Dayet Aoua au Maroc

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    L’étude consiste à la détermination de la qualité physicochimique des eaux du lac Dayet Aoua situé dans le Moyen Atlas au Maroc juste après son dernier desséchement survenu en été 2002. Les résultats d’analyse obtenus au cours de la période d’étude comprise entre février et juillet 2005, montrent que les eaux du lac sont bicarbonatées calciques et magnésiennes, dures à très dures. La dureté dépend essentiellement des ions magnésium. Les analyses des formes azotées et des orthophosphates des eaux du lac donnent des valeurs très faibles, et ne décèlent aucune sorte de pollution de type organique pouvant engendrer son eutrophisation, ce qui permet de le classeractuellement parmi les lacs oligotrophes.Mots-clés : lac, physico-chimie, pollution organique, oligotrophe

    Magnetic properties in amorphous Co95­xDyxZr5 thin films

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    Amorphous Co95-xDyxZr5 thin films were prepared by RF sputtering and their magnetic properties were studied as a function of temperature and for the composition range 0<x<30. The mean field theory has been used to explain the temperature dependence of the magnetization. The exchange interactions between Co-Co and Dy-Co atom pairs have been evaluated. The magnetic phase diagrams are presented.Amorphous Co95-xDyxZr5 thin films were prepared by RF sputtering and their magnetic properties were studied as a function of temperature and for the composition range 0<x<30. The mean field theory has been used to explain the temperature dependence of the magnetization. The exchange interactions between Co-Co and Dy-Co atom pairs have been evaluated. The magnetic phase diagrams are presented

    Speech Emotion Recognition Considering Local Dynamic Features

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    Recently, increasing attention has been directed to the study of the speech emotion recognition, in which global acoustic features of an utterance are mostly used to eliminate the content differences. However, the expression of speech emotion is a dynamic process, which is reflected through dynamic durations, energies, and some other prosodic information when one speaks. In this paper, a novel local dynamic pitch probability distribution feature, which is obtained by drawing the histogram, is proposed to improve the accuracy of speech emotion recognition. Compared with most of the previous works using global features, the proposed method takes advantage of the local dynamic information conveyed by the emotional speech. Several experiments on Berlin Database of Emotional Speech are conducted to verify the effectiveness of the proposed method. The experimental results demonstrate that the local dynamic information obtained with the proposed method is more effective for speech emotion recognition than the traditional global features.Comment: 10 pages, 3 figures, accepted by ISSP 201

    Key drivers for copepod assemblages in a eutrophic coastal brackish lake

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    The copepod assemblages and abiotic parameters were investigated at 11 stations in a large coastal lake (Lake Manzalah, Nile Delta) from 2009-2010 in order to verify any impacts of eutrophication and salinity on the copepod species composition. The environmental conditions and the copepod assemblages appeared to have changed in comparison with previous studies, possibly because of increasing eutrophication and invasions of non-indigenous species (NIS). The aim of the present study was the identification of species which can be used as ecological indicators of high trophic status. Among the nine copepod species of Lake Manzalah, Acartia tonsa, Mesocyclops ogunnus, and Apocyclops panamensis were reported for the first time. Acartia tonsa, a well-known NIS for the Mediterranean, numerically dominated the copepod assemblages in some portions of the lake. The distribution of Acanthocyclops trajani and Thermocyclops consimilis was insensible to eutrophication because they can stand high levels of nutrients and hypoxia. Compared with previous reports, the copepod assemblage of Lake Manzalah was richer in species. The invasions of NIS, in addition to the heterogeneous progress of eutrophication in the lake, created an environmental mosaic with many species in total, but with single areas suitable for only a small number of them

    Perceived Causes of Obstetric Fistula and Predictors of Treatment Seeking among Ugandan Women: Insights from Qualitative Research

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    Many obstetric fistula patients remain untreated or present late to treatment despite increasing surgical availability in Uganda. We explored women‘s perceptions of the cause of their obstetric fistula and their treatment seeking behaviours, including barriers and facilitators to timely care access. In-depth interviews and focus group discussions were conducted from June–August 2014 among 33 women treated for obstetric fistula at Mulago Hospital, Kampala. Data were analysed to describe dimensions and commonalities of themes identified under perceived causes and treatment seeking experiences, and their intersection. Perceived obstetric fistula causes included delays in deciding on hospital delivery, lengthy labour, injury caused by the baby, health worker incompetence, and traditional beliefs. Treatment seeking timing varied. Early treatment seeking was facilitated by awareness of treatment availability through referral, the media, community members, and support by partners and children. Barriers to early treatment seeking included inadequate financial and social support, erroneous perceptions about fistula causes and curability, incorrect diagnoses, and delayed or lack of care at health facilities. Our study supports broad educational and awareness activities, facilitation of social and financial support for accessing care, and improving the quality of emergency obstetric care and fistula treatment surgical capacity to reduce women‘s suffering. Keywords: Obstetric fistula, perceived causes, treatment seeking, maternal morbidity, UgandaDe nombreux patients atteints de fistule obstétricale restent non traités ou se présentent tardivement au traitement malgré une disponibilité chirurgicale croissante en Ouganda. Nous avons exploré la perception qu'ont les femmes de la cause de leur fistule obstétricale et de leurs comportements de recherche de traitement, y compris les obstacles et les facilitateurs pour un accès rapide aux soins. Des entretiens approfondis et des discussions de groupe ont été menés de juin à août 2014 auprès de 33 femmes traitées pour fistule obstétricale à l'hôpital de Mulago, Kampala. Les données ont été analysées pour décrire les dimensions et les points communs des thèmes identifiés sous les causes perçues et les expériences de recherche de traitement, et leur intersection. Les causes perçues de la fistule obstétricale comprenaient des retards dans les décisions d'accouchement à l'hôpital, un travail prolongé, des blessures causées par le bébé, l'incompétence des agents de santé et les croyances traditionnelles. Le calendrier de recherche du traitement variait. La recherche précoce d'un traitement a été facilitée par la sensibilisation à la disponibilité du traitement grâce à l'aiguillage, aux médias, aux membres de la communauté et au soutien des partenaires et des enfants. Les obstacles à la recherche d'un traitement précoce comprenaient un soutien financier et social inadéquat, des perceptions erronées sur les causes et la curabilité des fistules, des diagnostics incorrects et un retard ou un manque de soins dans les établissements de santé. Notre étude soutient de vastes activités d'éducation et de sensibilisation, la facilitation du soutien social et financier pour l'accès aux soins et l'amélioration de la qualité des soins obstétricaux d'urgence et du traitement chirurgical de la fistule pour réduire la souffrance des femmes.&nbsp; Mots-clés: Fistule obstétricale, causes perçues, recherche de traitement, morbidité maternelle, Ougand

    Coordination entities of a Pyrene-based Iminopyridine ligand: Structural and photophysical properties

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    A pyrene-based iminopyridine ligand L has been prepared and displays the absorption and emission properties expected for pyrene-based derivatives in solution. Ligand L, as well as two neutral and one monocationic coordination entities, respectively formulated as [ZnLCl2] 1, [ReLCl(CO)3] 3 and [CuL2](BF4) 2, have been crystallized and analyzed by single crystal X-ray diffraction analysis. The corresponding crystal structures indicate the formation of supramolecular architectures generated by offset π···π stacking between pyrene fragments and strong C-H···π interactions in coordination entity 1. For the cationic coordination entity 2, the crystal packing reveals the presence of C-H···F and C-H···π interactions and numerous C-H···π contacts interconnecting the molecules into a 3D network. As for coordination entity 3, hydrogen bonding and π···π stacking link the molecules in a three dimensional manner. Zinc (II) and copper (I) coordination entities have also been studied through isothermal titration calorimetry, which indicate a strong binding and a different stoichiometry for both coordination entities. Photophysical studies of the ligand and corresponding coordination entities show a monomer type pyrene emission and a higher fluorescence quantum yield for the zinc coordination entity 1 as compared with copper 2 and rhenium 3 coordination entities
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