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1.
PLoS One ; 12(5): e0177314, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28545112

RESUMEN

Animal home ranges typically characterized by their size, shape and a given time interval can be affected by many different biotic and abiotic factors. However, despite the fact that many studies have addressed home ranges, our knowledge of the factors influencing the size of area occupied by different animals is, in many cases, still quite poor, especially among raptors. Using radio-telemetry (VHF; 2.1 g tail-mounted tags) we studied movements of 20 Tengmalm's owl (Aegolius funereus) males during the breeding season in a mountain area of Central Europe (the Czech Republic, the Ore Mountains: 50° 40' N, 13° 35' E) between years 2006-2010, determined their average hunting home range size and explored what factors affected the size of home range utilised. The mean breeding home range size calculated according to 95% fixed kernel density estimator was 190.7 ± 65.7 ha (± SD) with a median value of 187.1 ha. Home range size was affected by prey abundance, presence or absence of polygyny, the number of fledglings, and weather conditions. Home range size increased with decreasing prey abundance. Polygynously mated males had overall larger home range than those mated monogamously, and individuals with more fledged young possessed larger home range compared to those with fewer raised fledglings. Finally, we found that home ranges recorded during harsh weather (nights with strong wind speed and/or heavy rain) were smaller in size than those registered during better weather. Overall, the results provide novel insights into what factors may influence home range size and emphasize the prey abundance as a key factor for breeding dynamics in Tengmalm's owl.


Asunto(s)
Fenómenos de Retorno al Lugar Habitual , Estrigiformes/fisiología , Animales , República Checa , Femenino , Masculino , Conducta Predatoria , Estaciones del Año , Conducta Sexual Animal
2.
PLoS One ; 10(10): e0138177, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26444564

RESUMEN

In altricial birds, energy supply during growth is a major predictor of the physical condition and survival prospects of fledglings. A number of experimental studies have shown that nestling body mass and wing length can vary with particular extrinsic factors, but between-year observational data on this topic are scarce. Based on a seven-year observational study in a central European Tengmalm's owl population we examine the effect of year, brood size, hatching order, and sex on nestling body mass and wing length, as well as the effect of prey abundance on parameters of growth curve. We found that nestling body mass varied among years, and parameters of growth curve, i.e. growth rate and inflection point in particular, increased with increasing abundance of the owl's main prey (Apodemus mice, Microtus voles), and pooled prey abundance (Apodemus mice, Microtus voles, and Sorex shrews). Furthermore, nestling body mass varied with hatching order and between sexes being larger for females and for the first-hatched brood mates. Brood size had no effect on nestling body mass. Simultaneously, we found no effect of year, brood size, hatching order, or sex on the wing length of nestlings. Our findings suggest that in this temperate owl population, nestling body mass is more sensitive to prey abundance than is wing length. The latter is probably more limited by the physiology of the species.


Asunto(s)
Comportamiento de Nidificación/fisiología , Estrigiformes/crecimiento & desarrollo , Estrigiformes/fisiología , Animales , Arvicolinae/fisiología , Fenómenos Biológicos/fisiología , Femenino , Masculino , Ratones , Fenómenos Fisiológicos/fisiología , Reproducción/fisiología , Conducta Sexual/fisiología , Alas de Animales/patología
3.
Pharm Dev Technol ; 12(4): 345-52, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17763139

RESUMEN

A fuzzy model has been developed for the optimization of high-shear wet granulation wetting on a plant scale depending on the characteristics of pharmaceutical active substance particles. The model optimized on the basis of experimental data involves a set of rules obtained from expert knowledge and full-scale process data. The skewness coefficient of particle size distribution and the tapped density of the granulated mixture were chosen as the model input variables. The output of the fuzzy ruled system is the optimal quantity of wetting liquid. In comparison to manufacturing practice, a very strong sensitivity of the optimal quantity of the added wetting liquid to the size and shape of the active substance particles has been identified by fuzzy modeling.


Asunto(s)
Excipientes/química , Lógica Difusa , Preparaciones Farmacéuticas/química , Tecnología Farmacéutica/métodos , Química Farmacéutica , Tamaño de la Partícula , Solubilidad , Agua/química , Humectabilidad
4.
Drug Dev Ind Pharm ; 32(5): 585-93, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16720413

RESUMEN

Pellets containing drugs of different properties were prepared in a Rotoprocessor in order to study changes in the formulation process and resulting pellet characteristics. Diltiazem hydrochloride, diclofenac sodium, and theophylline were chosen as model drugs. Pellet size distribution, sphericity, density, hardness, friability, and repose angle were determined using standard methods. The amount of water as a wetting agent necessary for successful pellet formulation was observed for each sample and changed depending on drug solubility, concentration, and particle size. The pelletization of freely soluble diltiazem hydrochloride required 24.8-23.1% of the wetting agent and its amount decreased as the drug concentration increased. The demand for water in the formulation of theophylline pellets was 31.0-34.4% and it increased with increasing drug concentration. The pellet samples containing both drugs were easy to prepare. However, the cohesion of micronized diclofenac sodium particles negatively influenced both the pellet size distribution and the formulation process itself. When the drug concentration exceeded 40%, it was not possible to produce pellets of an appropriate size and the process was not reproducible.


Asunto(s)
Química Farmacéutica , Composición de Medicamentos/instrumentación , Algoritmos , Antiinflamatorios no Esteroideos/administración & dosificación , Antiinflamatorios no Esteroideos/química , Broncodilatadores/administración & dosificación , Broncodilatadores/química , Bloqueadores de los Canales de Calcio/administración & dosificación , Bloqueadores de los Canales de Calcio/química , Celulosa , Diclofenaco/administración & dosificación , Diclofenaco/química , Diltiazem/administración & dosificación , Diltiazem/química , Excipientes , Lactasa/química , Tamaño de la Partícula , Solubilidad , Teofilina/administración & dosificación , Teofilina/química , Agua
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