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Le nombre de weblogs est en constante augmentation. Les adolescents sont toujours plus nombreux à utiliser la plate forme skyblog pour se raconter en ligne. L’utilisation de ce nouveau moyen de communication permet aux adolescents d’accomplir leur mission en favorisant notamment leur autonomie et la prise de responsabilité. Mais il est important que les parents les guident dans leurs apprentissages, afin de leur donner les armes nécessaires à la bonne utilisation de leur journal en ligne. Les travailleurs sociaux, doivent également se familiariser avec ce nouveau phénomène afin de pourvoir accompagner les jeunes sur la toile

New Data on Armadillos (Xenarthra: Dasypodidae) for Central Patagonia, Argentina

Armadillos represent the most diverse family of xenarthrans. Although many studies have been done on these mammals, several topics, such as their local distribution, natural history, behavioral ecology and conservation, remain poorly known. Chaetophractus villosus and Zaedyus pichiy are the most common armadillos in extra-Andean Patagonia, a vast area in southern Argentina and Chile that encompasses different ecosystems and has been modified by human activities, mainly by sheep grazing. In this work we present new data on the distribution, natural history, conservation, and ecology of C. villosus and Z. pichiy from central Patagonia (Chubut and Río Negro provinces, Argentina). We registered 60 localities for C. villosus and 35 for Z. pichiy that confirm their presence in wide sectors of central Patagonia. Furthermore, we confirmed that these two armadillo species suffer high rates of mortality due to their use as a protein source, hunting by dogs, road traffic, and poisoning, among others. We conclude that their populations are at risk of overexploitation and local extinction. The basic knowledge provided here will be a first step towards the conservation of these characteristic Patagonian mammals.Fil: Abba, Agustin Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; ArgentinaFil: Nabte, Marcela Janina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; ArgentinaFil: Udrizar Sauthier, Daniel Edgardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentin

Are owl pellets good estimators of prey abundance?

Some ecologists have been skeptics about the use of owl pellets to estimate small mammal's fauna. This is due to the assumptions required by this method: (a) that owls hunt at random, and (b) that pellets represent a random sample from the environment. We performed statistical analysis to test these assumptions and to assess the effectiveness of Barn owl pellets as a useful estimator of field abundances of its preys. We used samples collected in the arid Extra-Andean Patagonia along an altitudinal environmental gradient from lower Monte ecoregion to upper Patagonian steppe ecoregion, with a mid-elevation ecotone. To test if owls hunt at random, we estimated expected pellet frequency by creating a distribution of random pellets, which we compared with data using a simulated chi-square. To test if pellets represent a random sample from the environment, differences between ecoregions were evaluated by PERMANOVAs with Bray–Curtis dissimilarities. We did not find evidence that owls foraged non-randomly. Therefore, we can assume that the proportions of the small mammal's species in the diet are representative of the proportions of the species in their communities. Only Monte is different from other ecoregions. The ecotone samples are grouped with those of Patagonian steppes. There are no real differences between localities in the small mammal's abundances in each of these ecoregions and/or Barn owl pellets cannot detect patterns at a smaller spatial scale. Therefore, we have no evidence to invalidate the use of owl pellets at an ecoregional scale.Fil: Andrade, Analia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; ArgentinaFil: Menezes, Jorge Fernando Saraiva de. Universidade Federal do Rio de Janeiro; BrasilFil: Monjeau, Jorge Adrian. Universidade Federal do Rio de Janeiro; Brasil. Fundación Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Nidos de Oligoryzomys sp. y Holochilus brasiliensis (Rodentia, Cricetidae) en el este de la provincia de Entre Ríos, Argentina

Se describe la estructura y ubicación de los nidos de Oligoryzomys sp. y Holochilus brasiliensis en el este de la provincia de Entre Ríos, Argentina. Los nidos se hallaron asociados a cuerpos de agua. Los nidos de Oligoryzomys sp. se encontraron en sitios elevados, su tamaño medio fue de 18 cm de largo, 8 cm de ancho y 10 cm de alto. Los nidos de H. brasiliensis se localizaron a unos pocos centímetros sobre la superficie del agua, tenían una forma elipsoidal con medias de 22.5 cm de largo, 13 cm de ancho y 18.7 cm de alto. Se observó un patrón estacional en su construcción; esto podría indicar que estas especies construyen sus nidos durante la primavera y el verano para albergar sus crías. Estas especies tienen importancia sanitaria y económica por lo cual es importante conocer su biología en ambientes naturales para establecer un adecuado programa de control.We describe the structure and location of nests built by Oligoryzomys sp. and Holochilus brasiliensis in eastern Entre Ríos Province, Argentina. Nests were associated with water bodies. Nests of Oligoryzomys sp. averaged 18 cm length, 8 cm width, and 10 cm height and were found at elevated sites, while nests of H. brasiliensis were a few centimetres above water surface and had an ellipsoid shape with a mean size of 22.5 cm length, 13 cm width, and 18.7 cm height. A seasonal nest building pattern was observed that might indicate that these species construct their nests during spring and summer for breeding. Knowing the biology of these potential pest species of economic and public health importance in a natural environment will help defining an effective control program.Facultad de Ciencias Naturales y Muse

Mammalia, Didelphimorphia and Rodentia, southwest of the province of Mendoza, Argentina

We documented terrestrial micromammal assemblages at five localities of southwestern Mendoza province, Argentina. We added new localities for several of the most uncommon small mammal species of this region (e.g. Loxodontomys micropus and Tympanoctomys barrerae). Two main groups of terrestrial non-volant micromammals are represented in southwestern province of Mendoza: one group is related to the South American arid diagonal, and includes species typically adapted to the xeric environments of the Monte Desert; a second group includes Patagonian and High Andean species. Some Patagonian species reached in the study area their northernmost distributional records (e.g. Abrothrix longipilis, A. olivaceus, Chelemys macronyx, Loxodontomys micropus).Fil: Pardiñas, Ulises Francisco J.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Teta, Pablo Vicente. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Udrizar Sauthier, Daniel Edgardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentin

Nidos de Oligoryzomys sp. y Holochilus brasiliensis (Rodentia, Cricetidae) en el este de la provincia de Entre Ríos, Argentina

Se describe la estructura y ubicación de los nidos de Oligoryzomys sp. y Holochilus brasiliensis en el este de la provincia de Entre Ríos, Argentina. Los nidos se hallaron asociados a cuerpos de agua. Los nidos de Oligoryzomys sp. se encontraron en sitios elevados, su tamaño medio fue de 18 cm de largo, 8 cm de ancho y 10 cm de alto. Los nidos de H. brasiliensis se localizaron a unos pocos centímetros sobre la superficie del agua, tenían una forma elipsoidal con medias de 22.5 cm de largo, 13 cm de ancho y 18.7 cm de alto. Se observó un patrón estacional en su construcción; esto podría indicar que estas especies construyen sus nidos durante la primavera y el verano para albergar sus crías. Estas especies tienen importancia sanitaria y económica por lo cual es importante conocer su biología en ambientes naturales para establecer un adecuado programa de control.We describe the structure and location of nests built by Oligoryzomys sp. and Holochilus brasiliensis in eastern Entre Ríos Province, Argentina. Nests were associated with water bodies. Nests of Oligoryzomys sp. averaged 18 cm length, 8 cm width, and 10 cm height and were found at elevated sites, while nests of H. brasiliensis were a few centimetres above water surface and had an ellipsoid shape with a mean size of 22.5 cm length, 13 cm width, and 18.7 cm height. A seasonal nest building pattern was observed that might indicate that these species construct their nests during spring and summer for breeding. Knowing the biology of these potential pest species of economic and public health importance in a natural environment will help defining an effective control program.Facultad de Ciencias Naturales y Muse

Nidos de Oligoryzomys sp. y Holochilus brasiliensis (Rodentia, Cricetidae) en el este de la provincia de Entre Ríos, Argentina

Se describe la estructura y ubicación de los nidos de Oligoryzomys sp. y Holochilus brasiliensis en el este de la provincia de Entre Ríos, Argentina. Los nidos se hallaron asociados a cuerpos de agua. Los nidos de Oligoryzomys sp. se encontraron en sitios elevados, su tamaño medio fue de 18 cm de largo, 8 cm de ancho y 10 cm de alto. Los nidos de H. brasiliensis se localizaron a unos pocos centímetros sobre la superficie del agua, tenían una forma elipsoidal con medias de 22.5 cm de largo, 13 cm de ancho y 18.7 cm de alto. Se observó un patrón estacional en su construcción; esto podría indicar que estas especies construyen sus nidos durante la primavera y el verano para albergar sus crías. Estas especies tienen importancia sanitaria y económica por lo cual es importante conocer su biología en ambientes naturales para establecer un adecuado programa de control.We describe the structure and location of nests built by Oligoryzomys sp. and Holochilus brasiliensis in eastern Entre Ríos Province, Argentina. Nests were associated with water bodies. Nests of Oligoryzomys sp. averaged 18 cm length, 8 cm width, and 10 cm height and were found at elevated sites, while nests of H. brasiliensis were a few centimetres above water surface and had an ellipsoid shape with a mean size of 22.5 cm length, 13 cm width, and 18.7 cm height. A seasonal nest building pattern was observed that might indicate that these species construct their nests during spring and summer for breeding. Knowing the biology of these potential pest species of economic and public health importance in a natural environment will help defining an effective control program.Facultad de Ciencias Naturales y Muse

Développement d'une pico-turbine hydraulique pour alimenter des stations de mesures environnementales en zone de haute montagne

Le but de ce projet est de concevoir et de réaliser un système autonome utilisant l’énergie hydraulique des eaux d’une rivière pour alimenter des stations de mesures environnementales en zone de montagne pour le CreAlp

Characterization of Carbon-Contaminated B4C-Coated Optics after Chemically Selective Cleaning with Low-Pressure RF Plasma

Boron carbide (B4C) is one of the few materials that is expected to be mostly resilient with respect to the extremely high brilliance of the photon beam generated by free electron lasers (FELs) and is thus of considerable interest for optical applications in this field. However, as in the case of many other optics operated at modern light source facilities, B4C-coated optics are subject to ubiquitous carbon contaminations. These contaminations represent a serious issue for the operation of high performance FEL beamlines due to severe reduction of photon flux, beam coherence, creation of destructive interference, and scattering losses. A variety of B4C cleaning technologies were developed at different laboratories with varying success. We present a study regarding the low-pressure RF plasma cleaning of carbon contaminated B4C test samples via inductively coupled O2/Ar, H2/Ar, and pure O2 RF plasma produced following previous studies using the same IBSS GV10x downstream plasma source. Results regarding the chemistry, morphology as well as other aspects of the B4C optical coating before and after the plasma cleaning are reported. We conclude from these comparative plasma processes that pure O2 feedstock plasma only exhibits the required chemical selectivity for maintaining the integrity of the B4C optical coating.Comment: 27 pages, 15 figure