870 resultados para Rhinebeck Bird Club.


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Da una opinión valorativa, en base a fundamentos o criterios económicos, la importancia del Guanay, conocido en la ciencia como Phalacrocorax bouganvillei, en la producción del guano de isla y en el desarrollo económico del país, dándole el título de la ave más valiosa en el mundo.

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Aquest projecte consisteix en realitzar una pàgina web per a la secció de waterpolo del Club Natació Terrassa, de fàcil manteniment, per a que qualsevol dels responsables de la secció pugui dur a terme la seva actualització.

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Little is known about the maternal transfer of antibodies in natural host-parasite systems despite its possible evolutionary and ecological implications. In domestic animals, the maternal transfer of antibodies can enhance offspring survival via a temporary protection against parasites, but it can also interfere with the juvenile immune response to antigens. We tested the functional role of maternal antibodies in a natural population of a long-lived colonial seabird, the kittiwake (Rissa tridactyla), using a vaccine (Newcastle disease virus vaccine) to mimic parasite exposure combined with a cross-fostering design. We first investigated the role of prior maternal exposure on the interannual transmission of Ab to juveniles. We then tested the effect of these antibodies on the juvenile immune response to the same antigen. The results show that specific maternal antibodies were transferred to chicks 1 year after maternal exposure and that these antibodies were functional, i.e. they affected juvenile immunity. These results suggest that the role of maternal antibodies may depend on the timing and pattern of offspring exposure to parasites, along with the patterns of maternal exposure and the dynamics of her immune response. Overall, our approach underlines that although the transgenerational transfer of antibodies in natural populations is likely to have broad implications, the nature of these effects may vary dramatically among host-parasite systems, depending on the physiological mechanisms involved and the ecological context.

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1. The environment of parasites is determined largely by their hosts. Variation in host quality, abundance and spatial distribution affects the balance between selection within hosts and gene flow between hosts, and this should determine the evolution of a parasite's host-range and its propensity to locally adapt and speciate. 2. We investigated the relationship between host spatial distribution and (1) parasite host range, (2) parasite mobility and (3) parasite geographical range, in a comparative study of a major group of avian ectoparasites, the birds fleas belonging to the Ceratophyllidae (Siphonaptera). 3. Flea species parasitizing colonial birds had narrower host ranges than those infesting territorial nesters or birds with an intermediate level of nest aggregation. 4. The potential mobility and geographical ranges of fleas decreased with increasing level of aggregation of their hosts and increased with the fleas' host ranges. 5. Birds with aggregated nest distribution harboured more flea species mainly due to a larger number of specialists than solitarily nesting hosts. 6. These results emphasize the importance of host spatial distribution for the evolution of specialization, and for local adaptation and speciation in Ceratophyllid bird fleas.

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Major life history traits, such as fecundity and survival, have been consistently demonstrated to covary positively in nature, some individuals having more resources than others to allocate to all aspects of their life history. Yet, little is known about which resources (or state variables) may account for such covariation. Reactive oxygen species (ROS) are natural by-products of metabolism and, when ROS production exceeds antioxidant defenses, organisms are exposed to oxidative stress that can have deleterious effects on their fecundity and survival. Using a wild, long-lived bird, the Alpine Swift (Apus melba), we examined whether individual red cell resistance to oxidative stress covaried with fecundity and survival. We found that males that survived to the next breeding season tended to be more resistant to oxidative stress, and females with higher resistance to oxidative stress laid larger clutches. Furthermore, the eggs of females with low resistance to oxidative stress were less likely to hatch than those of females with high resistance to oxidative stress. By swapping entire clutches at clutch completion, we then demonstrated that hatching failure was related to the production of low-quality eggs by females with low resistance to oxidative stress, rather than to inadequate parental care during incubation. Although male and female resistance to oxidative stress covaried with age, the relationships among oxidative stress, survival, and fecundity occurred independently of chronological age. Overall, our study suggests that oxidative stress may play a significant role in shaping fecundity and survival in the wild. It further suggests that the nature of the covariation between resistance to oxidative stress and life history traits is sex specific, high resistance to oxidative stress covarying primarily with fecundity in females and with survival in males.

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Aplicación web para el Club Deportivo Maratón mediante la que se da a conocer el club y sus actividades e instalaciones. Así mismo, se proporciona una aplicación de escritorio para la gestión de los contenidos de la web.

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This leaflet includes information on programs for Women's Clubs. Some possible subjects for the club's discussions are literature, history and fine arts. Several methods of study are covered. Groups are encouraged to use public libraries and the Iowa Traveling Library to obtain reference materials for their topics.

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Este proyecto es un estudio que pretende realizar una aplicación dirigida a centros deportivos, implementando a través de BIOMAX el acceso a las instalaciones utilizando tarjetas de proximidad. Además la aplicación permitirá gestionar de forma eficiente a sus socios e instalaciones. De esta manera se consigue automatizar - mejorando en tiempo y calidad -una tarea imprescindible de realizar, control de accesos de forma sencilla y con un mantenimiento fácil por parte de los usuarios que la utilicen. Para ello se utilizará un dispositivo KIMALDI que nos permitirá gestionar el control de accesos

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L’etapa d’iniciació a l’esport té una importància majúscula en el procés d’aprenentatge dels jugadors, i per això també podem trobar dos tipus de clubs: els competitius, els quals estan influïts bàsicament pels resultats obtinguts; i els lúdics, on preval la diversió i el joc sobre l’especialització a l’esport. El que es pretén amb aquesta investigació és descobrir quins factors són més determinants per fer que les famílies escullin un tipus de club o un altre. Per tant, basant-nos amb el que diuen autors com Pacheco (2007), Wein (2004), Frattarola i Sans (2006) i Lasierra i Lavega (1993), s’han concretat una sèrie de factors determinants per l’elecció de cada tipus de club, així com d’altres que seran significatius per les famílies a l’hora de decantar-se per un o per l’altre. Pel que fa a la part metodològica, dir que és una investigació descriptiva transversal. A més, s’ha utilitzat l’estratègia de l’enquesta amb l’instrument del qüestionari, el qual s’ha basat en una mostra formada per 60 pares i mares de nens i nenes d’iniciació en l’esport, i 20 pares i mares de nens d’escoleta, previ a la iniciació esportiva. Pel que fa als resultats obtinguts, aquests mostren que al club lúdic es compleixen els tres factors d’aquest àmbit, mentre que al club competitiu es compleixen els dos mateixos factors lúdics de l’altre club i només un factor competitiu. D’altra banda, cal tenir present la importància que tenen els factors contaminadors en els resultats obtinguts degut a la significativitat d’aquests.