224 research outputs found
Evaluation of radiotagging techniques and their application to survival analysis of Red-legged Partridge Alectoris rufa chicks
A better knowledge of chick survival rates is required to enable understanding of the population dynamics of gamebirds and to develop management measures to conserve their populations. The Red-legged Partridge Alectoris rufa is a highly valued game species in Spain but its populations have declined in recent decades. A lack of appropriate monitoring methods has been a limitation in gaining information on the mortality of Red-legged Partridge chicks. We developed methods for the effective radiotagging of chicks in captivity and applied these methods in the field in northern Spain to estimate survival during the first 5 months of life. The most effective method for radiotagging captive chicks between 3 and 8 days old involved gluing small tags directly to the skin in the interscapular space using cyanoacrylate adhesive. Backpack harness tags attached with elastic bands were the most effective method of radiotagging 4-week-old chicks. Predation was the main cause of chick mortality identified during the field experiments. Survival between hatching and 5 months of age was estimated to be 16-21%. The lowest survival rates occurred during the first 7 days of life (62-70% cumulative survival) and this period seems to be a major determinant in the life history of the species.This study was the result of a research project co-funded by the Departamento de Medio Ambiente of Gobierno de Navarra and Consejo Superior de Investigaciones Científicas.Peer Reviewe
¿Puede el control de zorros mejorar la supervivencia de la perdiz roja (Alectoris rufa)? Un estudio experimental en el Norte de España
[EN]: This work evaluates the effectiveness of fox control as a method to improve the survival of red-legged partridge (Alectoris rufa). We radio-tracked 89 adult partridges and their chicks (62 few days old chicks and 46 over one-month-old chicks) and monitored their nests (N = 45) on two hunting estates in northern Spain over two years. Generalist predators (red fox, Vulpes vulpes, and magpie, Pica pica) were selectively controlled on one half of each estate during the first year, and on the other half in the second year. We estimated the effect of predator control on survival rates. Predator control did not improve survival rates for adult partridges and nests, but it improved chick survival, especially for chicks over one-month old.[ES]: Evaluamos la efectividad del control selectivo de zorros como método para mejorar la
supervivencia de la perdiz roja (Alectoris rufa). Para ello, radio–seguimos 89 perdices adultas y sus pollos (62 pollos de pocos días y 46 pollos de más de un mes de edad), e hicimos un seguimiento de sus nidos en dos
cotos de caza del Norte de España durante dos años. En la mitad de la superficie de cada coto se controlaron de forma selectiva los depredadores generalistas (zorro, Vulpes vulpes, y urracas, Pica pica) durante el primer año, y los tratamientos se invirtieron entre zonas durante el segundo año. Estimamos el efecto del control de depredadores sobre las tasas de supervivencia. El control de depredadores no mejoró la supervivencia de los adultos y nidos de perdiz, pero sí mejoró la supervivencia de los pollos, especialmente para los pollos de más de un mes de edad.This study was funded by the Department of Environment of Navarre Government and the Spanish Research Council (CSIC).Peer Reviewe
Stability analysis and estimate of the region of attraction of a human respiratory model
International audienceIn this paper, we complete the stability analysis of various human respiratory non-linear time delay models introduced in. More precisely, we present a detailed mathematical analysis of the stability of the nonlinear model trivial equilibrium , an estimate of its region of attraction and exponential estimates of the solutions starting in this region. The proposed approach is constructive and it is based on the use of Lyapunov-Krasovskii functionals of complete type for time-delay systems with a cross term in the time derivative
Effect of artificial warren size on a restocked European wild rabbit population
From the time since the decline of the wild rabbit Oryctolagus cuniculus in southern Europe, various techniques and methods have been explored with a view to restoring wild rabbit populations or increasing rabbit resilience, for both conservation and game purposesRabbit restocking and habitat management are among the measures most often appliedSome efforts have been made to increase refuges for wild rabbits, mainly through the construction of artificial warrensThe present study evaluates the response of a wild rabbit population introduced to artificial warrens of varying sizesThis involves comparisons of the density of rabbits in the warrens, rabbit density change between seasons of low and high rabbit population density and the productivity index for large and small warrens in rabbit populations living under semi-natural conditionsOur results show that large warrens had higher rabbit abundance than had small warrens, but significantly lower rabbit densityNo differences in density increase or productivity index were found with respect to warren sizeThe results suggest that it is preferable to build many small warrens for conservation of wild rabbit populations, but, in the event that only a few warrens are built, it is advisable that they be large.C. Rouco was supported by a postdoctoral grant from the regional government of Castilla-La Mancha (JCCM) and the European Social Fund. Funding was provided by the projects by Confederacion Hidrografica del Guadalquivir, by the Projects CGL2005-02340/BOS, CGL2009-11665, FAU2006-0014-C-02-02, POII09-0099-2557 and PEII09-0097-436.Peer Reviewe
A longer confinement period favors European wild rabbit (Oryctolagus cuniculus) survival during soft releases in low-cover habitats
Rabbit restocking is widely used in Spain for conservation and/or hunting purposes; however, the success of rabbit restocking is generally low. Thus, many studies have assessed ways to reduce this problem, one of which is the use of a ¿soft-release¿ procedure whereby rabbits are acclimated to their release site for a variable time period prior to release. This study assessed the short-term effects of two soft-release confinement periods on the survival of rabbits during an experimental restocking program carried out in southwest Spain. The post-release survival rate of rabbits confined at the release site for six nights was significantly higher than that of rabbits confined for three nights. The longer acclimation period after rabbit translocation minimized mortality while rabbits adapted to their new environment.C. Rouco was supported by a postdoctoral grant from the regional government of Castilla-La Mancha (JCCM), and the European Social Fund. Funding was provided by the projects by Confederación Hidrográfica del Guadalquivir, by the Projects CGL2005-02340/BOS, FAU2006-0014-C-02-02, PAI06-170, and PREG-05-022.Peer Reviewe
Steep clines within a highly permeable genome across a hybrid zone between two subspecies of the European rabbit
PMCID: PMC3633729.-- et al.Maintenance of genetic distinction in the face of gene flow is an important aspect of the speciation process. Here, we provide a detailed spatial and genetic characterization of a hybrid zone between two subspecies of the European rabbit. We examined patterns of allele frequency change for 22 markers located on the autosomes, X-chromosome, Y-chromosome and mtDNA in 1078 individuals sampled across the hybrid zone. While some loci revealed extremely wide clines (w ≥ 300 km) relative to an estimated dispersal of 1.95-4.22 km/generation, others showed abrupt transitions (w ≈ 10 km), indicating localized genomic regions of strong selection against introgression. The subset of loci showing steep clines had largely coincident centers and stepped changes in allele frequency that did not co-localize with any physical barrier or ecotone, suggesting that the rabbit hybrid zone is a tension zone. The steepest clines were for X- and Y-chromosome markers. Our results are consistent with previous inference based on DNA sequence variation of individuals sampled in allopatry in suggesting that a large proportion of each genome has escaped the overall barrier to gene flow in the middle of the hybrid zone. These results imply an old history of hybridization and high effective gene flow and anticipate that isolation factors should often localize to small genomic regions.This work was partially supported by POPH-QREN funds from the European Social Fund and Portuguese MCTES [Ph.D. and postDoc grants to MC (SFRH/BD/23786/2005; SFRH/
BPD/72343/2010)], by FEDER funds through the COMPETE program and Portuguese national funds through the FCT—Fundaçao para a Ciencia e a Tecnologia—(PTDC/BIA-BDE/72304/2006; PTDC/BIA-EVF/111368/2009; PTDC/CVT/122943/2010; CGL2009-11665; POII09-0099-2557), and by National Science Foundation and National Institutes of Health grants to MWN. SJEB’s contributions, and development of the inference tools used, were partially funded by a Fundaçao para a Ciencia e a Tecnologia grant to SJEB (PTDC/BIA-BEC/103440/2008).Peer Reviewe
Estudio de factibilidad para la instalación de una planta procesadora de frutas para producir babaco en almíbar
Babaco in syrup is a traditional home made preserve, which is widely consumed in the Ecuadorian Andean regions. This product was developed by using the babaco, water, sugar and cardamom as the ingredients for gastronomic gourmet foods. The product not contains preservative to maintain the characteristics of the product and the process used. In addition, we have tried to maintain the characteristics of the fruit and the ethnicity of the Ecuadorian cuisine.Babaco en almíbar es una conserva tradicionalmente casera que es muy consumida en la región andina ecuatoriana. El producto desarrollado utiliza babaco, agua, azúcar y cardamomo como materias primas para darle una insinuación gastronómica de tipo gourmet. No se usan preservantes por las características del producto y del proceso. Además pretende recuperar un fruto endémico y una tradición alimenticia ecuatoriana y procesarlo industrialmente. Se midió el nivel de agrado del producto de la empresa FRELAN y el desarrollado por nosotros (Conservas Valdivia), el análisis estadístico no encontró diferencia significativa entre las muestras
Influencia de los gases de metano en la seguridad industrial y el ambiente del trabajador en la planta de compostaje/vermicompost en el Ex Fundo Oquendo Del Callao
Objetivos: determinar el nivel de relación entre el gas de metano y enfermedades ocupacional de
tipo respiratorias del trabajador en la planta compostaje/vermicompost. Métodos: la investigación
es mixta cualitativa-cuantitativa, descriptivo no experimental con el uso de método. Resultados:
el 13 % de los encuestados manifiestan haber presentado síntomas de Infecciones (de tipo
respiratorio), mientras que el 12% manifestaron sufrir los ojos irritados y llorosos, del mismo modo
el 11% afirma haber sido afectado de la secreción nasal en un nivel de influencia medio. De
acuerdo con correlación Rho de Spearman el resultado de correlación es de 0,590 de acuerdo con
los datos obtenidos el gas de metano están relacionados en un nivel positivo con la enfermedad
ocupacional de tipo respiratoria, es decir si se reduce los niveles de metano en el aire existirá
menores síntomas de influencia de enfermedad de tipo respiratorio. Conclusiones: se concluye
que los niveles de influencia del gas de metano en la salud del trabajador de acuerdo con los
síntomas manifestado por los colaboradores son de nivel medio y muy bajo en la planta de
compostaje/vermicompost por ser un proceso aeróbico, con respecto al nivel significancia es de
0.001 menor que 0.05 entonces es aceptado la hipótesis alterna y rechazamos la hipótesis nula
Influencia de los gases de metano en la seguridad industrial y el ambiente del trabajador en la planta de compostaje/vermicompost en el Ex Fundo Oquendo Del Callao
Objetivos: determinar el nivel de relación entre el gas de metano y enfermedades ocupacional de
tipo respiratorias del trabajador en la planta compostaje/vermicompost. Métodos: la investigación
es mixta cualitativa-cuantitativa, descriptivo no experimental con el uso de método. Resultados:
el 13 % de los encuestados manifiestan haber presentado síntomas de Infecciones (de tipo
respiratorio), mientras que el 12% manifestaron sufrir los ojos irritados y llorosos, del mismo modo
el 11% afirma haber sido afectado de la secreción nasal en un nivel de influencia medio. De
acuerdo con correlación Rho de Spearman el resultado de correlación es de 0,590 de acuerdo con
los datos obtenidos el gas de metano están relacionados en un nivel positivo con la enfermedad
ocupacional de tipo respiratoria, es decir si se reduce los niveles de metano en el aire existirá
menores síntomas de influencia de enfermedad de tipo respiratorio. Conclusiones: se concluye
que los niveles de influencia del gas de metano en la salud del trabajador de acuerdo con los
síntomas manifestado por los colaboradores son de nivel medio y muy bajo en la planta de
compostaje/vermicompost por ser un proceso aeróbico, con respecto al nivel significancia es de
0.001 menor que 0.05 entonces es aceptado la hipótesis alterna y rechazamos la hipótesis nula
Extending the deterministic Riemann-Liouville and Caputo operators to the random framework: A mean square approach with applications to solve random fractional differential equations
[EN] This paper extends both the deterministic fractional Riemann¿Liouville integral and the Caputo fractional
derivative to the random framework using the mean square random calculus. Characterizations and sufficient
conditions to guarantee the existence of both fractional random operators are given. Assuming mild
conditions on the random input parameters (initial condition, forcing term and diffusion coefficient), the
solution of the general random fractional linear differential equation, whose fractional order of the derivative
is ¿ ¿ [0, 1], is constructed. The approach is based on a mean square chain rule, recently established,
together with the random Fröbenius method. Closed formulae to construct reliable approximations for the
mean and the covariance of the solution stochastic process are also given. Several examples illustrating
the theoretical results are included.This work has been partially supported by the Ministerio de Economia y Competitividad grant MTM2013-41765-P. The co-author Prof. L. Villafuerte acknowledges the support by Mexican Conacyt.Burgos, C.; Cortés, J.; Villafuerte, L.; Villanueva Micó, RJ. (2017). Extending the deterministic Riemann-Liouville and Caputo operators to the random framework: A mean square approach with applications to solve random fractional differential equations. Chaos, Solitons and Fractals. 102:305-318. https://doi.org/10.1016/j.chaos.2017.02.008S30531810
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