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101.
Comparison between organic and conventional kiwifruit cultivars 'Hayward' and 'Bidan', which was done by four radical scavenging assays, ESI-MS, and DSC measurements, showed significant differences between the cultivars. Such results were not estimated in kiwifruit growing under organic and conventional conditions. The extraction of bioactive compounds was done by two different methods: sequential extraction with ethyl acetate followed by methanol and maceration with methanol and ethyl acetate. The highest yield of polyphenols was found in the new cultivar 'Bidan' in comparison with the classic 'Hayward', by direct extraction with methanol. This is the first investigation of 'Bidan' kiwifruit cultivar, grown under organic conditions and compared with 'Hayward' organic. High contents of bioactive compounds and antioxidant and antiproliferative properties of the two kiwifruit cultivars justify their use as sources of valuable antioxidants. It is necessary to continue this study as a long-term experiment to eliminate the influence of seasonality.  相似文献   
102.
Habitat connectivity is important for the survival of species that occupy habitat patches too small to sustain an isolated population. A prominent example of such a species is the European bison (Bison bonasus), occurring only in small, isolated herds, and whose survival will depend on establishing larger, well-connected populations. Our goal here was to assess habitat connectivity of European bison in the Carpathians. We used an existing bison habitat suitability map and data on dispersal barriers to derive cost surfaces, representing the ability of bison to move across the landscape, and to delineate potential connections (as least-cost paths) between currently occupied and potential habitat patches. Graph theory tools were then employed to evaluate the connectivity of all potential habitat patches and their relative importance in the network. Our analysis showed that existing bison herds in Ukraine are isolated. However, we identified several groups of well-connected habitat patches in the Carpathians which could host a large population of European bison. Our analysis also located important dispersal corridors connecting existing herds, and several promising locations for future reintroductions (especially in the Eastern Carpathians) that should have a high priority for conservation efforts. In general, our approach indicates the most important elements within a landscape mosaic for providing and maintaining the overall connectivity of different habitat networks and thus offers a robust and powerful tool for conservation planning.  相似文献   
103.
New Forests - Cultivation of seedlings in trays requires the use of specifically developed substrates. This study presents the results of the analyses of selected physical and mechanical parameters...  相似文献   
104.
Polyglutamylation of tubulin has been implicated in several functions of microtubules, but the identification of the responsible enzyme(s) has been challenging. We found that the neuronal tubulin polyglutamylase is a protein complex containing a tubulin tyrosine ligase-like (TTLL) protein, TTLL1. TTLL1 is a member of a large family of proteins with a TTL homology domain, whose members could catalyze ligations of diverse amino acids to tubulins or other substrates. In the model protist Tetrahymena thermophila, two conserved types of polyglutamylases were characterized that differ in substrate preference and subcellular localization.  相似文献   
105.
Summary To assess the reliability of dot-spot hybridization assay for the Potato Spindle Tuber Viroid, more than 1000 potato samples were cross-tested by biological and hybridization methods. Both methods gave similar results with a range of cultivars. The dot-spot hybridization test was reproducible with formaldehyde-denaturated cell-sap samples stored at room temperature for over 6 months. This finding means that samples can be transported from field stations to a diagnostic laboratory and allows for cross-checking of results between laboratories. The data suggest that dot-spot hybridization is suitable for breeding and quarantine purposes.  相似文献   
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