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Capsule The highest densities of Meadow Pipits in Central Europe are found in lowland and upland wet meadows.Aims To create a large-scale predictive model of Meadow Pipit density.Methods We analysed factors affecting the density of the Meadows Pipit in Poland using data from 777?×?1?km study plots and a set of 22 environmental variables, including agriculture intensification and habitat-specific plant species as classifiers of meadow types. Predictors were selected using variation inflation factor, then related to species density data using generalized additive models.Results The best-supported model included 11 variables and was clearly better (Akaike information criterion weight?=?0.47) than other models. The density of the Meadow Pipit reaches its highest levels on large areas of extensively used wet meadows as well as pastures where livestock graze and which show high photosynthetic activity in April.Conclusion Some aspects of the environment that were not identified from remote sensing data were vital for determining relatively high density. Conservation efforts for preserving Meadow Pipit populations should focus on maintaining wet meadows and extensively grazed pastures. Given the results, the Meadows Pipit may be classified as a good indicator of traditional agriculture. 相似文献
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AIM OF THE STUDY: To establish whether there is a clinical correlation between clinical outcome or quality of life and radiographic findings. MATERIAL AND METHODS: 17 patients (mean age 68.2 years) with total knee arthroplasty were examined after an average follow-up of 24.6 months. The examination included the HSS score for clinical parameters, and the SF-36 questionnaire quality of life. Radiographs were evaluated in accordance with Ewald and Lotke, and a schema of our own. RESULTS: The HSS score returned a mean of 81 points, and the SF-36 questionnaire showed significantly poorer results in comparison with age-matched healthy subjects. The Lotke evaluation of the X-rays showed a mean value of 76.3. Correlations between the radiographic findings and the HSS score were not seen. Correlations between X-ray parameters (Ewald and Lotke) and the SF-36 were found only for pain and vitality. CONCLUSIONS: This is the first study to investigate the correlation between clinical parameters (including quality of life) and X-ray findings. Neither the clinical score nor the quality of life score was found to correlate with the radiographic findings. Nor was more than minimal correlation found between quality of life and HSS score. These results show that the presence of radiolucent lines or deviations from the perfect prosthesis position must not necessarily be considered to be of importance for clinical outcome and quality of life. 相似文献
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The Ortolan bunting Emberiza hortulana was censused in Poland during the Common Breeding Birds Monitoring Project in 2003–2009. Data from 683 monitoring polygons,
covering in total more than 0.23% of the country, were used in the analysis. Based on the data and environmental information
gathered in GIS databases (Corine land cover “CLC2000 and 2006” database, digital elevation model “GTOPO30” dataset, “Wordclim”
dataset, and NDVI dataset), we modeled a habitat- and spatial-related variation of the Ortolan bunting’s presence. Birds were
recorded in 13.2% grid cells. The mean density was 0.5 individual/km2. We modeled the spatial presence of birds using multivariate adaptive regression splines (MARS). Then models were cross-validated
to check their consistency. The environment-use model shows that the Ortolan bunting prefers extensively cultivated farmland
dominated by non-irrigated arable fields, small coniferous and mixed forests, complex cultivation patterns, and meadows. The
preferred areas are located on lowlands in western and central parts of the country where the climate is the driest and warmest.
Such a repeatable spatial pattern model of the population helped to create a predictive map of the Ortolan bunting’s presence
in Poland. The general rule is that the probability gradient of its presence increases from the northeastern part of the country
to the central and southwestern parts of Poland. Additionally, the Ortolan bunting avoids severe continental climate and regions
with dense ground-level vegetation. 相似文献
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During the last decades, farmland habitats in central European countries have changed significantly, seriously affecting populations of many farmland bird species. We compiled available published data on densities of three owl species, Athene noctua, Asio otus and Strix aluco collected in the Polish farmland. All results of censuses based on the playback method conducted between 1980–2005 were included in the analysis. The proportions of grassland, fields, built-up land and forest at each studied plot were estimated and used as predictors in additive models. Proportions of main land use types, extracted with the principal component analysis, explained much of the variation found in owl densities, although some of the relationships were nonlinear. In general, owl densities were found to be affected positively by a high percentage of grasslands and built-up land, and negatively by the amount of fields and forests. Little owl densities showed a significant negative trend over the study period. It seems that high prey availability is an important factor accounting for the positive relationship between grassland proportion and owl density. The significant decrease in grassland areas and increase in forest coverage that were recently recorded in Poland may thus negatively affect populations of the three owl species studied here. 相似文献
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We developed predictive maps of farmland and forest species richness which are based on the “focal species concept” and remote sensing data. We explored environmental preferences of 17 farmland and 33 forest species in Poland, using data from the Pan-European Monitoring Scheme. The largest number of farmland species was noted in the central and eastern parts, while the opposite trend was observed in the case of forest species, where the preferred areas were in the north and south-east. The most important environmental component affecting the bird faunas of farmland and forest was a gradient from arable fields to forest. This relationship is unimodal, which means that on a meso-geographical scale the highest species richness occurred in heterogeneous landscapes where fields are interspersed with forest. Our results also indicate that the geographical gradient in Poland's bird fauna can simply be attributed to the habitat-based distinction: western and central parts are dominated by large agricultural habitats and coniferous forest, while in other areas predominate mixed forests and extensively used farmland. Among the climatic factors, only rainfall influenced the farmland bird species. Its effect is non-linear, but positive, which means that in areas with higher rainfall more species are recorded.Our predictive maps are complementary to research on population trends, and can be an essential tool for effective management and conservation of species populations on a trans-national scale. 相似文献
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Continent‐scale global change attribution in European birds ‐ combining annual and decadal time scales 下载免费PDF全文
Peter Søgaard Jørgensen Katrin Böhning‐Gaese Kasper Thorup Anders P. Tøttrup Przemysław Chylarecki Frédéric Jiguet Aleksi Lehikoinen David G. Noble Jiri Reif Hans Schmid Chris van Turnhout Ian J. Burfield Ruud Foppen Petr Voříšek Arco van Strien Richard D. Gregory Carsten Rahbek 《Global Change Biology》2016,22(2):530-543
Species attributes are commonly used to infer impacts of environmental change on multiyear species trends, e.g. decadal changes in population size. However, by themselves attributes are of limited value in global change attribution since they do not measure the changing environment. A broader foundation for attributing species responses to global change may be achieved by complementing an attributes‐based approach by one estimating the relationship between repeated measures of organismal and environmental changes over short time scales. To assess the benefit of this multiscale perspective, we investigate the recent impact of multiple environmental changes on European farmland birds, here focusing on climate change and land use change. We analyze more than 800 time series from 18 countries spanning the past two decades. Analysis of long‐term population growth rates documents simultaneous responses that can be attributed to both climate change and land‐use change, including long‐term increases in populations of hot‐dwelling species and declines in long‐distance migrants and farmland specialists. In contrast, analysis of annual growth rates yield novel insights into the potential mechanisms driving long‐term climate induced change. In particular, we find that birds are affected by winter, spring, and summer conditions depending on the distinct breeding phenology that corresponds to their migratory strategy. Birds in general benefit from higher temperatures or higher primary productivity early on or in the peak of the breeding season with the largest effect sizes observed in cooler parts of species' climatic ranges. Our results document the potential of combining time scales and integrating both species attributes and environmental variables for global change attribution. We suggest such an approach will be of general use when high‐resolution time series are available in large‐scale biodiversity surveys. 相似文献
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Judith W.J. Bergs Przemek M. Krawczyk Tijana Borovski Rosemarie ten Cate Hans M. Rodermond Jan Stap Jan Paul Medema Jaap Haveman Jeroen Essers Chris van Bree Lukas J.A. Stalpers Roland Kanaar Jacob A. Aten Nicolaas A.P. Franken 《DNA Repair》2013,12(1):38-45
In S and G2 phase mammalian cells DNA double strand breaks (DSBs) can potentially be repaired by homologous recombination (HR) or non-homologous end-joining (NHEJ). Results of several studies suggest that these two mechanistically distinct repair pathways can compete for DNA ends. Because HR and NHEJ differ with respect to error susceptibility, generation of chromosome rearrangements, which are potentially carcinogenic products of DSB repair, may depend on the pathway choice. To investigate this hypothesis, the influence of HR and NHEJ inhibition on the frequencies of chromosome aberrations in G2 phase cells was investigated. SW-1573 and RKO cells were treated with mild (41 °C) hyperthermia in order to disable HR and/or NU7441/cisplatin to inactivate NHEJ and frequencies of chromosomal fragments (resulting from unrepaired DSBs) and translocations (products of erroneous DSB rejoining) were studied using premature chromosome condensation (PCC) combined with fluorescence in situ hybridization (FISH).It is shown here that temporary inhibition of HR by hyperthermia results in increased frequency of ionizing-radiation (IR)-induced chromosomal translocations and that this effect is abrogated by NU7441- or cisplatin-mediated inhibition of NHEJ. The results suggest that in the absence of HR, DSB repair is shifted to the error-prone NHEJ pathway resulting in increased frequencies of chromosomal rearrangements. These results might be of consequence for clinical cancer treatment approaches that aim at inhibition of one or more DSB repair pathways. 相似文献
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Przemek A. Gorski Catharine A. Trieber Ghazaleh Ashrafi Howard S. Young 《The Journal of biological chemistry》2015,290(11):6777-6788
The sarcoplasmic reticulum calcium pump (SERCA) is regulated by the small integral membrane proteins phospholamban (PLN) and sarcolipin (SLN). These regulators have homologous transmembrane regions, yet they differ in their cytoplasmic and luminal domains. Although the sequences of PLN and SLN are practically invariant among mammals, they vary in fish. Zebrafish (zf) appear to harbor multiple PLN isoforms, one of which contains 18 sequence variations and a unique luminal extension. Characterization of this isoform (zfPLN) revealed that SERCA inhibition and reversal by phosphorylation were comparable with human PLN. To understand the sequence variations in zfPLN, chimeras were created by transferring the N terminus, linker, and C terminus of zfPLN onto human PLN. A chimera containing the N-terminal domain resulted in a mild loss of function, whereas a chimera containing the linker domain resulted in a gain of function. This latter effect was due to changes in basic residues in the linker region of PLN. Removing the unique luminal domain of zfPLN (53SFHGM) resulted in loss of function, whereas adding this domain to human PLN had a minimal effect on SERCA inhibition. We conclude that the luminal extension contributes to SERCA inhibition but only in the context of zfPLN. Although this domain is distinct from the SLN luminal tail, zfPLN appears to use a hybrid PLN-SLN inhibitory mechanism. Importantly, the different zebrafish PLN isoforms raise the interesting possibility that sarcoplasmic reticulum calcium handling and cardiac contractility may be regulated by the differential expression of PLN functional variants. 相似文献