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The objective of the study was to analyze the wing musculature of the African ostrich. The investigation was conducted on four three-day old chicks of the ostrich. The muscles were characterized by poor development due to a very young age, and no flight abilities. The basic muscle units were described, the measurements of their length and width were taken and their mutual relation was calculated. All values were collected in a table. The photographic documentation was also prepared.
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The extent of the pterosaur flight membrane

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The shape and extent of the membranous brachioptagium in pterosaurs remains a controversial topic for those attempting to determine the aerodynamic performance of the first vertebrate fliers. Various arguments in favour of the trailing edge terminating against either the torso or hip, the femur, the ankle, or different locations for various taxa, has resulted in several published reconstructions. Uncertainty over the correct model is detrimental to both aerodynamic and palaeoecological studies that are forced to simultaneously consider multiple and highly variable configurations for individual taxa. A review of relevant pterosaur specimens with preserved soft tissues or impressions of the wing membrane, however, strongly suggests that the trailing edge of the wing extended down to the lower leg or ankle in all specimens where the brachiopatagium is completely preserved. This configuration is seen across a phylogenetically broad range of pterosaurs and is thus likely to have been universally present throughout the Pterosauria. Support for opposing hypotheses where the trailing edge terminates against the body, hip, or knee are based on several specimens where the wing membrane is either incomplete or has undergone post−mortem contraction. An ankle attachment does not rule out a high aspect ratio wing as the curvature of the trailing edge and the ratio of the fore to hind limbs also play a major role in determining the final shape of the membrane.
Background. Marination is a good method to enhance attractiveness of chicken wings, which are considered by consumers as least attractive. Sensory value of marinated wings is dependent largely on the flavour of skin, because they contain proportionally more skin than other carcass elements. Moreover, skin constitutes a natural barrier, which may facilitate or hinder the penetration of marinade components, depending on the conformation State of proteins it is composed of primarily collagen. The aim of the study was to investigate the effect of specific marinades on thermal stability of collagen - the main component of skin proteins using differential scanning calorimetry (DSC). Material and methods. Chicken wings were marinated using model marinades, marinades prepared according to original recipes and ready-to-use marinades used in industrial practice. Marinated skin samples were weighted (approx. 10 mg) and analyzed by DSC. Heating rate was 5°C/min, within the range from 20 to 100°C. Results. In analyses using model marinades denaturation temperature (Tmax) of collagen was reduced by approx. 3°C and enthalpy (AH) was lowered by approx. 40%. An even bigger reduction of collagen denaturation temperature (by approx. 7°C) and enthalpy AH (by approx. 48%) was found after the application of marinades prepared following original recipes (W1, W2, W3). In tum, the application of model marinades containing NaCl and organic acids (acetic or citric) resulted in stabilization of collagen, which was manifested by an inerease of enthalpy (AH) by approx. 50% (for marinade containing 2% citric acid). Conclusions. Temperature and enthalpy of collagen denaturation was dependent on type of marinade. The extent of collagen denaturation affects nutritional and sensory value. Considering that time and temperature of intensive heat treatment are important factors in the formation process of carcinogenic compounds i.e. heterocyclic aromatic amines, it bis important to choose these marinades, which reduce the denaturation temperature and enthalpy of proteins.
The wing morphology of bats is very diverse, and may correlate with energetic, behavioural, and ecological demands. If these demands conflict, wing shape may reflect compromise solutions. In this study, we compared the wing morphology of two bats, Tadarida brasiliensis (Geoffroy, 1824) and Myotis chiloensis (Waterhouse, 1828), that differ in body size, habitat, and foraging behaviour. We analyzed features of bio- mechanical and energetic relevance, and sought evidence of compromise solutions to energetic, ecological, and behavioural demands. We found that wing span of both species conformed to expectations based on allometric relationships, but that although the wing area of M. chiloensis did not differ from predictions, the wing area of T. brasiliensis was lower. M. chiloensis possessed an unusually low second moment of area of the humerus. Wing form of M. chiloensis is consistent with highly maneuverable flight needed to live between shrubs and wooded habitats, and its low aspect ratio and low wing loading indicate a high energetic cost and a low flight speed, respectively. The low humeral second moment of area may be related to a reduction of wing mass and may result in decreased inertial power. In contrast, T. brasiliensis showed high aspect ratio and wing loading, characteristic of high speed, energetically economic flight.
We studied the wing morphology, echolocation calls, diet and emergence time of the black-bearded tomb bat (Taphozous melanopogon) from May to October 2006 in Guangxi Province, southwest China. Taphozous melanopogon has wings with high aspect ratio, high loading and pointed wing-tip shape-characteristics associated with fast flight in open space. This species usually produces low-intensity, low frequency, and frequency-modulated (FM) calls usually containing up to four harmonics, with most energy in the second (or sometimes third) harmonic. The diet of this species consists mostly of Lepidoptera and Hemiptera. Timing of evening emergence is correlated with the time of sunset. This is the first study to describe the flight and echolocation behavior of this species in China, and opens the way for future studies of its biology.
Socially parasitic and globally threatened Phengaris (=Maculinea) arion (L.) is one of the most intensively investigated insect species in Europe. Although current studies focus on ecology and genetics, the butterfly has also attracted attention because of its morphology. An extremely variable black pattern on the blue background of the wing upperside has resulted in the description of many different forms or even subspecies. We studied the variation of 148 individuals from five regional populations at a latitudinal gradient in Poland: two north-eastern populations, one middle-eastern populations and two southern populations. A proportion of the area covered with marginal strips and spots was measured, and the presence/absence of particular elements was also analyzed. For all except one, the most northern region, we found significant sexual dimorphism, with females being darker than males. Within sexes, the melanization level was higher in the north-east than in the south, and the mid - eastern region showed intermediate characteristics. Differences in colouration overlapped with variation in host ant use, but neither feature corresponded with the available genetic data and therefore clinal variation is a more likely explanation for the observed pattern. Melanization level may be an adaptation to climatic conditions, but it remains unclear which strategy of dorsal basking is applied by P. arion.
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