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This paper discusses different aspects of asymmetry of empirical distributions. An attempt was made to clarify the definition of such distributions and to identify some of the problems associated with commonly used skewness coefficients of As and γ and their interpretation and those yet requiring further research.
The basic assumption of the study was the existence – on a global scale – of the unequal distribution of the manufacturing factors created by the foreign direct investment. The attempt of careful examination and later presentation of the findings on the asymmetric character of the greenfield international economic initiatives configuration, in relation to various sectors and space, was assumed to be the main objective of the following study. Empirical analysis of the investment projects, completed between the years 2003-2012, with the use of the selected statistical methods and indicators (of variability, correlation, structure, dynamics and investment readiness of economy) were employed for the accomplishment of the task. The research appeared to prove the asymmetric distribution of the greenfield foreign investment, basically due to the structuralized changeability of the global economy. Generally, this asymmetry concerned the value of the investments, the number of projects under realization and their concentration in particular sectors of economy. Particularly clear disproportions were observed in the geographical structure, whereas the unit value of the realized projects could have been described as relatively proportional.
We investigated fluctuating asymmetry in 13 traits of the skulls and jaws of historical and contemporary populations of Scandinavian gray wolves (Canis lupus). We hypothesized that there is a higher level of fluctuating asymmetry in the inbred contemporary population than in the historical population. Our analyses did not detect any difference in the level of fluctuating asymmetry as predicted. We propose different explanation for this lack of change in fluctuating asymmetry. It is assumed that a large number of studies have failed to find a positive correlation between the level of genetic stress and developmental instability and have therefore never been published, which hampers a good understanding of fluctuating asymmetry as an indicator of developmental instability. The current study is thus important in this context. The gray wolf population in Scandinavia is characterized by an extreme bottleneck followed by two and a half decades of strong inbreeding, but no associated change in fluctuating asymmetry is detected.
Asymmetry analysis was conducted on four morphometric bilateral characters and one meristic character of Leiognathus equulus (Forsskal) collected from the Sea of Oman at the city of Muscat. The results showed that the level of asymmetry of the characters of preorbital distance and head length is higher than that of the rest of the characters studied. Increasing asymmetry values with fish length were noted in preorbital and postorbital distances and head length. This might be the result of incomplete development. The possible cause of asymmetry in this species is discussed in relation to different pollutants and their presence in the area.
Introduction. Tennis is a sport that requires asymmetric movements. Asymmetry in tennis pertains to the player carrying a racket and using it to hit the ball. An asymmetric tennis technique may lead to an asymmetric distribution of muscle mass and unbalanced muscle tonus. These disproportions will result in an improper body stature and may even cause irregularities in the skeletal structure. Aim of the Study. The aim of this study was to determine the degree of muscle mass asymmetry and its association with the dominant upper limb. Material and Methods. The study included 16 active tennis players: 15 right-handed and 1 left-handed. The control group (UN) comprised 16 non-training middle school pupils: 14 right-handed and 2 left-handed. Body composition was determined by means of bioelectrical impedance analysis (BIA). Results. Signifi cant differences between the dominant and non-dominant arms in tennis players were observed. The players featured a higher muscle mass of the dominant upper limb compared to the non-dominant limb. Similar differences were not observed amongst the controls. The control group was characterized with markedly lower asymmetry than the tennis players in terms of muscle mass distribution in the upper limbs (p < 0.05). No signifi cant correlations were found between age or training experience and the asymmetry coeffi cient values. Conclusions. The study revealed a signifi cant infl uence of sport training on asymmetry in muscle mass distribution in the upper limbs.
A total of 14 patients of various ages diagnosed with schizophrenia and, as an age-matched control group, 12 healthy subjects were examined using the MRI method of neuro-imaging. The volume of the following structures was evaluated in the right and left hemispheres: the superior temporal gyrus, the basolateral temporal area (the region including the middle temporal gyrus, inferior temporal gyrus and fusiform gyrus), the parahippocampal gyrus, the hippocampal head, the amygdaloid body and the inferior horn of the lateral ventricle. In schizophrenia a significant increase in the volume of the amygdaloid body on both the left and right sides was observed. In the patients, as in the control group, we noticed significant asymmetry between the left and right sides in the volume of the structures studied. The left amygdaloid body was significantly larger than the right, whereas the left hippocampal head and the temporal horn of the lateral ventricle were smaller than the right. Our findings suggest that in the early stages of schizophrenia, despite the increased volume of the amygdaloid body, the asymmetry between the structures of the temporal lobe is still present. However, the changes observed in the temporal lobe could be related to the functional disturbances observed in this disease.
Fluctuating asymmetry in 30 bilateral cranial non-metric traits was investigated in three roe deer Capreolus capreolus (Linnaeus, 1758) populations living in different habitats in Poland. For each sample, the mean proportion of asymmetric traits per individual {FAnm) was calculated and used for comparisons among populations. The highest value of FAnm (0.18) was displayed by roe deer belonging to the 'field ecotype', a lower one by roe deer belonging to the 'forest ecotype' (0.14), and the lowest (0.12) in a 'transient' population. In contrast to the 'forest' roe deer and the 'transient' population, a gradual and statistically significant decrease of FANM-values over the last 30 years was recorded in the 'field ecotype'. There the proportion of asymmetric traits was also significantly higher in juveniles than in other age classes. Fluctuating asymmetry in roe deer is discussed with regard to the environmental stress hypothesis and the gradual development of a coadapted gene pool in the 'field ecotype'.
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Cytotaxonomic studies of three ornamental aroids

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Cytotaxanomical analysis carried out on three ornamental aroids (Anchomanes difformis, Anchomanes hookeri and Arum maculatum) proved that cytological studies is none negligible tool in phylogeny and scientific classificationns of plants. Aceto-orcein stain squash technique was used in this study. Anchomanes difformis and Anchomanes. hookeri showed more relatedness in chromosome number and chromosome morphology, sharing the same chromosome number 2n=13, while Arum maculatum has 2n=8. The following karyotypes formular were revealed: 2n=8=3M+3SM+2ST in Arum maculatum; 2n=13=5M+1SM+7ST in A. difformis; and 2n=13=3M+6SM+4 A. hookeri. Other karyotype parameters investigated like CI%, AsI and degree of asymmetry of the genomes supported current taxonomic ranking.
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