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51.
Capsule?Of 26 species of wintering waterbirds, 18 showed an increase in numbers, five showed a decrease and two showed no change.

Aim?To assess long-term trends in the numbers and distribution of the 26 most abundant wintering waterbird species in the Czech Republic.

Methods?We used International Waterbird Census data from between 48 and 639 wetland sites which had been counted annually in the Czech Republic from 1966 to 2008. From these data long-term changes in numbers and distributions were determined. Log-linear Poisson regression analysis was used to estimate missing data using trim software. The distribution of each species was described as the ratio of the number of sites occupied by that species to the total number of sites investigated.

Results?Increasing trends were found for 18 species, five species were found to be declining, one species was stable and two species were found with uncertain trends. Wintering distributions (the ratio of sites occupied by a given species to the total number of sites counted) increased in 16 species and decreased in two species, broadly correlated with the species changes in numbers.

Conclusion?In most species changes in numbers as well as changes in distribution followed the Western Palearctic population trends. Those species which increased were mainly piscivores and included geese, ducks and gulls. Scarcer species also exhibited an increase in numbers. The changes in numbers (both positive and negative) were more frequent among species associated with running water, whereas species which showed uncertain trends were more frequently recorded on standing water, which is more affected by variable weather conditions.  相似文献   
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The objective of the current study is to develop a new cryomacroscope prototype for the study of vitrification in large-size specimens. The unique contribution in the current study is in developing a cryomacroscope setup as an add-on device to a commercial controlled-rate cooler and in demonstration of physical events in cryoprotective cocktails containing synthetic ice modulators (SIM)—compounds which hinder ice crystal growth. Cryopreservation by vitrification is a highly complex application, where the likelihood of crystallization, fracture formation, degradation of the biomaterial quality, and other physical events are dependent not only upon the instantaneous cryogenic conditions, but more significantly upon the evolution of conditions along the cryogenic protocol. Nevertheless, cryopreservation success is most frequently assessed by evaluating the cryopreserved product at its end states—either at the cryogenic storage temperature or room temperature. The cryomacroscope is the only available device for visualization of large-size specimens along the thermal protocol, in an effort to correlate the quality of the cryopreserved product with physical events. Compared with earlier cryomacroscope prototypes, the new Cryomacroscope-III evaluated here benefits from a higher resolution color camera, improved illumination, digital recording capabilities, and high repeatability in tested thermal conditions via a commercial controlled-rate cooler. A specialized software package was developed in the current study, having two modes of operation: (a) experimentation mode to control the operation of the camera, record camera frames sequentially, log thermal data from sensors, and save case-specific information; and (b) post-processing mode to generate a compact file integrating images, elapsed time, and thermal data for each experiment. The benefits of the Cryomacroscope-III are demonstrated using various tested mixtures of SIMs with the cryoprotective cocktail DP6, which were found effective in preventing ice growth, even at significantly subcritical cooling rates with reference to the pure DP6.  相似文献   
53.
Several β-carbonic anhydrases (CAs, EC 4.2.1.1) are present in all land plants examined thus far. Here we report the first detailed biochemical characterization of one such isoform, FbiCA 1, from the C4 plant Flaveria bidentis, which was cloned, purified and characterized as recombinant protein. FbiCA 1 has an interesting CO2 hydrase catalytic activity (kcat of 1.2 × 105 and kcat/Km of 7.5 × 106 M?1 × s?1) and was moderately inhibited by most simple/complex inorganic anions. Potent FbiCA 1 inhibitors were also detected, such as trithiocarbonate, diethyldithiocarbamate, sulfamide, sulfamic acid, phenylboronic acid and phenylarsonic acid (KIs in the range of 4–60 μM). Such inhibitors may be used as tools to better understand the role of various β-CA isoforms in photosynthesis.  相似文献   
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A convenient synthetic route and the characterization of complexes trans-[PtCl2(L)(PPh3)] (L = Et2NH (2), (PhCH2)2NH (3), (HOCH2CH2)2NH) (4) are reported. The antiproliferative activity was evaluated on three human tumor cell lines. The investigation on the mechanism of action highlighted for the most active complex 4 the capacity to affect mitochondrial functions. In particular, both the induction of the mitochondrial permeability transition phenomenon and an aspecific membrane damage occurred, depending on concentration.  相似文献   
56.
We report the synthesis and bio-pharmacological evaluation of a class of pyrrole derivatives featuring a small appendage fragment (carbaldehyde, oxime, nitrile) on the central core. Compound 1c proved to be extremely effective in vivo, showing an interesting anti-nociceptic profile that is comparable to reference compounds already marketed, hence representing a great stimulus for a further improvement of this class of molecules.  相似文献   
57.
Aerobic biodegradation of propylene glycol by soil bacteria   总被引:1,自引:0,他引:1  
Propylene glycol (PG) is a main component of aircraft deicing fluids and its extensive use in Northern airports is a source of soil and groundwater contamination. Bacterial consortia able to grow on PG as sole carbon and energy source were selected from soil samples taken along the runways of Oslo Airport Gardermoen site (Norway). DGGE analysis of enrichment cultures showed that PG-degrading populations were mainly composed by Pseudomonas species, although Bacteroidetes were found, as well. Nineteen bacterial strains, able to grow on PG as sole carbon and energy source, were isolated and identified as different Pseudomonas species. Maximum specific growth rate of mixed cultures in the absence of nutrient limitation was 0.014 h?1 at 4 °C. Substrate C:N:P molar ratios calculated on the basis of measured growth yields are in good agreement with the suggested values for biostimulation reported in literature. Therefore, the addition of nutrients is suggested as a suitable technique to sustain PG aerobic degradation at the maximum rate by autochthonous microorganisms of unsaturated soil profile.  相似文献   
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A great number of flavored grape varieties, of significant oenological potential, are traditionally cultivated in north-western Italy, besides the renowned “Moscato bianco” (syn. “Muscat à petits grains blancs”). Understanding their origin, besides its historical and scientific interest, would help to increase market appeal and consequently facilitate the commercial exploitation of these products. Twenty-four aromatic genotypes were investigated for their identity, kinship relations, and genetic origins through molecular markers (SSR and SNPs) supported by plant morphology and historical information. Flavored grape genotypes from other regions, possible ancestors, and reference cultivars of known pedigree were also included in the analysis. Kinship analysis used a likelihood-based approach (IBS, IBD, relatedness coefficients, and likelihood ratios) to achieve strong statistical support. The analyses revealed two possible leading genitors, in turn closely related by a parent/offspring relationship: “Moscato bianco” and “Malvasia aromatica di Parma,” a female grape cultivar that is today almost extinct. The outlined molecular and statistical approach could be applied for the investigation on the origin of ancient traditional cultivars of other vegetative propagated species.  相似文献   
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