797 research outputs found

    PREOVULATORY CHANGES AND OVULATION IN CATTLE UNDERGOING SPONTANEOUS OR CLOPROSTENOL-INDUCED LUTEOLYSIS

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    The follicular population, diameter of the ovulatory and subordinate follicles, corpus luteum (CL) size, concentration of progesterone and estradiol-17p were studied following spontaneous or cloprostenol-induced luteolysis. A total of 14 heifers received cloprostenol treatment on Day 9-11 of the cycle to synchronize their estrus. Subsequently, they were divided into two groups, one group which was allowed to undergo spontaneous luteolysis and the other group in which estrus was induced from days 9 to 12. In the induced-group, transrectal ultrasonography were performed daily started two days prior to injection until the onset of estrus. In the spontaneous-group, ultrasonography was done daily from day 15 until the onset of estrus. In both groups scanning were performed every 4 h from the onset of estrus until ovulation was ascertained. Small (SF, 2-4 mm), medium (MF.5-9 mm ) and large (LF,>9mm) size follicles were recorded. The diameter of largest and subordinate follicles were measured and blood were drawn from jugular vein at approximately around scanning and the plasma were used for measurement of progesterone (P4) and estradiol-17p (E2) concentration. There was no different in term of number of SF, MF and LF (P>0.05) between the two groups. Similarly, no effect of side (left vs. right ovary) and CL position (ipsi- vs contralateral to the ovary) was found (P>0.05). However, it was demonstrated that mean number of ovulatory follicles was higher (PO.01) in the spontaneously ovulating group while the regressing-CL size was larger in the cloprostenol induced animals (

    UseDa - un nouvel outil de base de données sur les utilisations ethnobotaniques des plantes de l'Afrique de l'Ouest

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    Das Wissen ĂŒber die Nutzung von Wildpflanzen in Westafrika und ihre verschiedenen Anwendungen ist in zahlreichen, breit gestreuten Publikationen dokumentiert und oft in Form von grauer Literatur schwer zugĂ€nglich. Mehrere Online-Datenbanken umfassen Informationen aus diesen Quellen und bieten zusammenfassende Kurzbeschreibungen der Pflanzen Nutzungen. Unser Ziel ist es, zusĂ€tzlich eine Datenbank (UseDa) fĂŒr ethnobotanische PrimĂ€rdaten aus Interviews aufzubauen. Damit können quantitative Daten extrahiert und synthetisiert werden. Es können DatensĂ€tze nach verschiedenen Fragestellungen analysiert werden, z.B. der Frage nach verwendeten Arten in bestimmten Gebieten, durch verschiedene ethnische Gruppen oder unterschiedliche Nutzergruppen, was fĂŒr die praktische Anwendung auf lokaler Ebene von Bedeutung ist. In diesem Artikel geben wir einen Überblick ĂŒber den technischen Aufbau und den Inhalt der Datenbank und diskutieren am Ende den möglichen Output fĂŒr die praktische Anwendung. Die Datenbank wurde im Rahmen des EU-geförderten Projekt UNDESERT aufgebaut.Knowledge about useful plants and their various applications in West Africa is scattered over many publications and often in form of grey literature difficult to access. Several online-databases compile large scale information from these sources and provide comprehensive summarized descriptions of plant usages. Our aim is to additionally build up a database (UseDa) for primary ethnobotanical interview data. Thus, quantitative data can be extracted and synthesized and data sets can be treated according to different research questions analyzing for example uses in specific areas, of different ethnic groups or user groups, which is essential for practical applications on a local level. In this article we give an overview on the technical structure and the content of the database and discuss at the end the possible output for practical application. The database was set up in the frame of the EU-funded Project UNDESERT.La connaissance sur les plantes utiles et leurs diverses applications en Afrique de l'Ouest sont dispersĂ©es sur de nombreuses publications et souvent difficiles d'accĂšs car souvent publiĂ©es sous la forme de littĂ©rature grise. Plusieurs bases de donnĂ©es en ligne compilent Ă  grande Ă©chelle des informations provenant de ces sources et fournissent des descriptions synthĂ©tiques des usages des plantes. Notre objectif est de construire une base de donnĂ©es (UseDa) pour les donnĂ©es primaires des enquĂȘtes ethnobotaniques. Ainsi, les donnĂ©es quantitatives peuvent ĂȘtre extraite et synthĂ©tisĂ©e et elles peuvent ĂȘtre traitĂ©es selon diffĂ©rentes questions de recherche analysant par exemple leurs utilisations dans des zones spĂ©cifiques, par diffĂ©rents groupes ethniques ou groupes d'utilisateurs, ce qui est essentiel pour les applications pratiques au niveau local. Dans cet article, nous donnons un aperçu sur la structure technique et le contenu de la base de donnĂ©es et discutons Ă  la fin les options possibles pour une application pratique. La base de donnĂ©es a Ă©tĂ© mise en place dans le cadre du projet UNDESERT financĂ© par l'UE

    Field emissions of N2O during biomass production may affect the sustainability of agro-biofuels

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    Field emissions of N2O during cultivation of bioenergy crops may counterbalance a considerable part of the avoided fossil CO2 emissions that are achieved by fossil fuel displacemen

    Evaluation of marine Synechococcus for an algal biorefinery in arid regions

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    Implementing microalgae biorefinery in arid environments requires utilization of strains that can grow at high temperatures (above 28 °C) and salinity levels (above 30 ppt). In this study, we investigate the newly isolated seawater strain, Synechococcus, native to the United Arab Emirates, and evaluate its value as a perspective organism for cultivation (for fuel and bio-products) in regions with freshwater scarcity. The strain displayed tolerance to a wide range of temperature (22–37 °C) and salinity (20–41 ppt), with maximum biomass concentration of 0.72 g L−1 and a maximum growth rate of 82 mg L−1 d−1 at 25 °C and 33 ppt salinity. Lipids accumulation reached up to 26% of dry weight in nitrogen-depleted conditions (with 1.8 mM of nitrates addition to the media), whereas protein content exceeded 50% dry weight. In this study, harvesting is investigated using three chemical agents: Ferric chloride, sodium hydroxide, and chitosan. Cell disruption is analyzed for four distinct treatments: Enzymatic, alkaline, ultrasonic, and hydrothermal. Among tested methods, flocculation with sodium hydroxide and ultrasonication were found to be the most efficient techniques for harvesting and cell disruption, respectively. The growth characteristics of the local strain and the potential to derive protein and lipids from it makes it a promising biomass in a biorefinery context

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    Le West African Data and Metadata Repository : une archive de données à long terme pour les ensembles de données écologiques de l'Afrique de l'Ouest

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    Obwohl zunehmend Daten fĂŒr ökologische Studien gebraucht werden, gehen noch immer viele Daten verloren oder sind mangels geeigneter Datenarchive nicht sichtbar genug. Mit dem West African Data and Metadata Repository stellen wir ein Langzeitdatenarchiv fĂŒr eine datenarme Region vor, das eine detaillierte Dokumentation mit Metadaten nach dem EML-Standard erlaubt und Datenhaltern die Möglichkeit gibt, Datenzugangsebenen und Nutzungsbedingungen zu bestimmen. Dieser Artikel gibt einen Überblick zu Struktur, Funktionen und Inhalt. Das Repositorium ist online unter der URL http://westafricandata.senckenberg.de.Although there is an increasing need for data in ecological studies, many datasets are still lost or not sufficiently visible due to a lack of appropriate data archives. With the West African Data and Metadata Repository, we present a secure long-term archive for a data-poor region allowing detailed documentation by metadata following the EML standard and giving data holders the opportunity to define levels of data access and conditions of use. This article gives an overview of structure, functions and content. The repository is online at the URL http://westafricandata.senckenberg.de.Bien qu'il existe un besoin croissant de donnĂ©es dans les Ă©tudes Ă©cologiques, de nombreux ensembles de donnĂ©es sont encore perdues ou pas suffisamment visibles en raison d'un manque d'archives de donnĂ©es appropriĂ©es. Avec le West African Data and Metadata Repository, nous prĂ©sentons une archive sĂ©curisĂ© Ă  long terme pour une rĂ©gion pauvre en donnĂ©es permettant une documentation dĂ©taillĂ©e par des mĂ©tadonnĂ©es suivant la norme EML et donnant aux propriĂ©taires de donnĂ©es la possibilitĂ© de dĂ©finir des niveaux de l'accĂšs aux donnĂ©es et les conditions d'utilisation. Cet article donne un aperçu de la structure, des fonctions et du contenu. Le rĂ©fĂ©rentiel est en ligne Ă  l'adresse URL http://westafricandata.senckenberg.de
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