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841.
842.
Slavomír Stašiov Lucia Uhorskaiová Marek Svitok Lenka Hazuchová Vladimír Vician Karol Kočík 《Biologia》2011,66(1):149-155
The paper is aimed at evaluation of the influence of two different agricultural management forms on harvestman (Opiliones)
communities structure in relation to the optimization of land use on the model territory of Agricultural Cooperative (AC)
Očová (Central Slovakia). The research was carried out using pitfall trapping through growing seasons from 2005 to 2007. Harvestmen
were captured at four pairs of sites (8 sites in total). For each pair of sites the cultivation of the same crop with application
of two different forms of agricultural management (conventional form and sustainable form with basic sustainable agro-environmental
scheme) was characteristic. In total, 667 individuals of 8 species of the Phalangiidae family were captured during the research.
The research results confirm the influence of management form on the structure of harvestman communities only partially. The
obtained data indicate that the management form plays a significant role, especially in such agrocoenoses, in which the same
crop is cultivated for several years (e.g., sites with alfalfa or permanent lawn), i.e., on the sites without ploughing or
use of other similar agrotechnical measures. In these cases, the sites with the sustainable agro-environmental scheme showed
higher diversity and equability of harvestman communities than the sites with the conventional form of agrotechnical management.
Harvestman communities structure on sites with crop rotation and repeated ploughing was more influenced by additional factors
than by the agricultural management form. 相似文献
843.
844.
Biomedical companies extract blood from the horseshoe crab, Limulus polyphemus, for the production of Limulus Amebocyte Lysate, used worldwide for detecting endotoxins in injectable solutions and medical devices. Despite the extensive use of horseshoe crabs by the biomedical industry, total hemolymph volume for this species is not known. The hemolymph volume of 60 adult horseshoe crabs was estimated using an inulin dilution technique. Blood volume of the horseshoe crab represented as a percentage of wet body weight was 25?±?2.2% for males and 25?±?5.1% (mean?±?SD) for females. Relationships between hemolymph volume and weight (p?=?0.0026, r 2?=?0.8762), hemolymph volume and prosomal width (p?<?0.0001), and hemolymph volume and inter-ocular width (p?<?0.0001) were observed. No significant differences were observed between males and females. The relationship of animal size and hemolymph volume can be used to predict how much blood can be drawn from horseshoe crabs used by the biomedical industry, and can be of further use in future bleeding mortality studies. 相似文献
845.
846.
The seed germination and seedling establishment ofAlisma gramineum, A. lanceolatum andA. plantago-aquatica were investigated to find differences in the reproductive strategy of these species and to explain their ecological and distributional differentiation. The influences of stratification, temperature and flooding on seed germination, winter survival of seedlings and their further development were tested in the laboratory and in the experimental garden. Seeds of the all species studied were dormant immediately after harvesting. Cold stratification was necessary for successful germination. Seeds germinated best under shallow water in temperatures of 25 °C and 25/10 °C and did not need fluctuating day/night temperatures to break dormancy. Seedlings established best under the limosal-terrestrial conditions in summer, and overwintered successfully only when flooded. The main interspecific differences found were in the percentage of germinative and dormant seeds, in the germination rates after individual treatments, in the course of ontogenetic development and in the longevity as well as in the resistance of vegetative organs to environmental conditions. Possible effects of the above-listed facts on the ecological amplitude and distribution of the studied species are discussed. 相似文献
847.
Raman spectroscopy has proven to be a valuable tool for analyzing various types of forensic evidence such as traces of body fluids. In this work, Raman spectroscopy was employed as a nondestructive technique for the analysis of dry traces of oral fluid to differentiate between smoker and nonsmoker donors with the aid of advanced statistical tools. A total of 32 oral fluid samples were collected from donors of differing gender, age and race and were subjected to Raman spectroscopic analysis. A genetic algorithm was used to determine eight spectral regions that contribute the most to the differentiation of smokers and nonsmokers. Thereafter, a classification model was developed based on the artificial neural network that showed 100% accuracy after external validation. The developed approach demonstrates great potential for the differentiation of smokers and nonsmokers based on the analysis of dry traces of oral fluid. 相似文献
848.
Árvay Július Šnirc Marek Hauptvogl Martin Bilčíková Jana Bobková Alica Demková Lenka Hudáček Marek Hrstková Miroslava Lošák Tomáš Král Martin Kováčik Anton Štefániková Jana 《Biological trace element research》2019,190(1):226-233
Biological Trace Element Research - The aim of the present study was to determine concentrations of 15 macro- and micro-elements in 10 commercially available plantation Arabica coffee brands. The... 相似文献
849.
850.
Katerina Zabrady Marek Adamus Lucie Vondrova Chunyan Liao Hana Skoupilova Marketa Novakova Lenka Jurcisinova Aaron Alt Antony W. Oliver Alan R. Lehmann Jan J. Palecek 《Nucleic acids research》2016,44(3):1064-1079
SMC5/6 is a highly conserved protein complex related to cohesin and condensin, which are the key components of higher-order chromatin structures. The SMC5/6 complex is essential for proliferation in yeast and is involved in replication fork stability and processing. However, the precise mechanism of action of SMC5/6 is not known. Here we present evidence that the NSE1/NSE3/NSE4 sub-complex of SMC5/6 binds to double-stranded DNA without any preference for DNA-replication/recombination intermediates. Mutations of key basic residues within the NSE1/NSE3/NSE4 DNA-binding surface reduce binding to DNA in vitro. Their introduction into the Schizosaccharomyces pombe genome results in cell death or hypersensitivity to DNA damaging agents. Chromatin immunoprecipitation analysis of the hypomorphic nse3 DNA-binding mutant shows a reduced association of fission yeast SMC5/6 with chromatin. Based on our results, we propose a model for loading of the SMC5/6 complex onto the chromatin. 相似文献