1,721,023 research outputs found
Contribution à la gestion durable du bassin versant du Wouri par une étude de la répartition de sa faune culicidienne (Littoral-Cameroun)
No full textContribution to the sustainable management of the Wouri watershed by a study of the distribution of its culicidian fauna (Littoral-Cameroon).
A comparative study of the culicidian diversity and productivity of the Wouri River and its shoreline has been carried out to evaluate the possibility of preserving the water course from a "larviciding" which will affect fishery resources during anti-larval campaigns. The study stations on the Wouri River and the larval breeding sites on its bank have been mapped, their culicidian productivity as well as their physico-chemical parameters measured. The sampled mosquitoes were identified morphologically and those of the Anopheles gambiae complex by molecular biology. Eight types of breeding sites were recorded on the bank with a higher frequency of artificial lodges with significantly higher culicidian productivity than natural deposits. The culicidian communities of the Wouri River and its shore had a specific similarity. However, 93 % of all mosquitoes sampled and 94 % of the malaria vectors identified came from the shoreline. The preservation of the Wouri River could be envisaged during the "larviciding" campaigns in view of its culicidian productivity, its ecological and socio-economic importance.Une étude comparative entre la diversité et la productivité culicidiennes du fleuve Wouri et celles de sa rive a été menée pour évaluer la possibilité de préserver le cours d’eau d’un "larviciding" qui affecterait les ressources halieutiques lors des campagnes anti-larvaires. Les stations d’étude sur le fleuve Wouri et les gîtes larvaires de sa rive ont été cartographiés, leur productivité culicidienne ainsi que leurs paramètres physico-chimiques mesurés. Les moustiques échantillonnés ont été identifiés morphologiquement et ceux du complexe Anopheles gambiae par la biologie moléculaire. Huit types de gîtes larvaires ont été répertoriés sur la rive avec une fréquence plus élevée des gîtes artificiels dont la productivité culicidienne était significativement plus élevée que celle des gîtes naturels. Les communautés culicidiennes du fleuve Wouri et de sa rive présentaient une similarité spécifique. Cependant 93 % de l’ensemble des moustiques échantillonnés et 94 % des vecteurs du paludisme identifiés provenaient de la rive. La préservation du fleuve Wouri pourrait être envisagée lors des campagnes de "larviciding" compte tenu de sa productivité culicidienne, de son importance écologique et socio-économique.Mbida Mbida Arthur, Ntonga Akono Patrick, Awono Ambene Parfait, Simo Wopo Hermann, Talipouo Abdou, Tchoffo Fobasso Romeo, Dongmo Alain, Lehman Gustave, Mimpfoundi Remy. Contribution à la gestion durable du bassin versant du Wouri par une étude de la répartition de sa faune culicidienne (Littoral-Cameroun). In: Revue d'Écologie (La Terre et La Vie), tome 73, n°4, 2018. pp. 550-558
Habitats larvaires et sensibilité des vecteurs du paludisme aux insecticides dans des localités (semi-urbaine et rurale) de la région du littoral camerounais : données préliminaires
No full textLarval habitats and susceptibility of malaria vectors to insecticides in semi-urban and rural localities of the Coast-Cameroon region : preliminary data.
Choosing an appropriate strategy for mosquito control in an eco-climatic facies requires knowledge of vector ecology, including the spatial distribution and productivity of larval habitats and their level of susceptibility to insecticides. This study maps, characterizes the mosquito breeding sites and evaluates the susceptibility to insecticides of malaria vectors to Banya II and Bodiman, two semi-urban and rural areas of the coastal region of Cameroon. The field surveys were conducted in May 2015. The mosquito breeding sites were geo-referenced. For each breeding site, larvae were collected then reared and physico-chemical parameters measured in situ. The susceptibility of vectors to dichlorodiphenyltrichloroethane (DDT), deltamethrin and permethrin was evaluated on the anopheline obtained from larva rearing. A variety of breeding sites has been identified in the study sites (ponds, rivers, ditches, tires, plastic wrap, water storage containers, abandoned containers, papaya holes, bamboo holes). However, Anopheles gambiae s. l, the most abundant species in Banya II was more common in the pools, while Culex poicilipes, the most abundant species in Bodiman was mainly collected in abandoned containers. The two categories of breeding sites had respectively electrical conductivity of 167.5 [16.9-305] and 170.43 [11.6-461] μs/cm, salinity of 90.5 [23.5-157] and 94.63[15-240] g/l and total dissolved solids of 119.6 [20.6-215] and 123.3 [7.8-354] ppm. Insecticides tests revealed mortality rates below 85 % for the Banya II Strain of A. gambiae s. l. and over 98 % for the Bodiman strain of A. nili. These informations should be taken into account for a better orientation of control strategies in order to control effectively the vectors in the study localities.Le choix d’une stratégie appropriée de lutte anti-paludique dans un faciès éco-climatique donné requiert une bonne connaissance de l’écologie des vecteurs, notamment la distribution spatiale et la productivité des gîtes larvaires, et de leur niveau de sensibilité aux insecticides. La présente étude cartographie, caractérise les gîtes de ponte des moustiques et évalue la susceptibilité aux insecticides des vecteurs de paludisme à Banya II et Bodiman, deux localités l’une sub-urbaine et l’autre rurale, de la région du littoral camerounais. Les enquêtes sur le terrain ont été menées en mai 2015. Les gîtes de moustiques ont été géo-réferencés. Pour chaque gîte, les larves ont été prélevées puis élevées et les paramètres physico-chimiques mesurés in situ. La sensibilité des vecteurs au Dichlorodiphényltrichloroéthane (DDT), à la Deltaméthrine et à la Perméthrine a été évaluée sur les anophèles issus de l’élevage des larves. Une diversité de gîtes a été identifiée dans les sites d’étude (mares, cours d’eau, caniveaux, pneus, emballages-plastiques, récipients de réserve d’eau, récipients abandonnés, trous de papayer, trous de bambou). Cependant, Anopheles gambiae s. l., l’espèce la plus abondante à Banya II a été plus fréquente dans les mares, alors que Culex poicilipes, l’espèce la plus abondante à Bodiman a été majoritairement collectée dans des récipients abandonnés. Les deux catégories de gîtes avaient respectivement une conductivité électrique de 167,5 [16,9-305] et 170,43 [11,6-461] μs/cm ; une salinité de 90,5 [23,5-157] et 94,6 [15-240] g/l ; un total de solides dissous (TDS) de 119,6 [20,6-215] et 123,3 [7,8-354] ppm. Les trois insecticides testés ont induit des taux de mortalité inférieurs à 85 % pour la souche Banya II d’A. gambiae s. l. et supérieurs à 98 % pour la souche Bodiman d’A. nili. Les présentes informations devraient être prises en compte pour une meilleure orientation des stratégies de lutte si l’on veut contrôler efficacement les vecteurs dans les localités d’étude.Ntonga Akono Patrick, Mbida Mbida Arthur, Awono Ambene Parfait, Youmbi Enga Lyonnais, Abdel Kayoum Yomon, Kekeunou Sévilor. Habitats larvaires et sensibilité des vecteurs du paludisme aux insecticides dans des localités (semi-urbaine et rurale) de la région du littoral camerounais : données préliminaires. In: Revue d'Écologie (La Terre et La Vie), tome 73, n°2, 2018. pp. 132-141
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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