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61.
The model SONOX has been developed that replicates the sequence of events on the way from emission of sulfur and nitrogen to the potential risk to forest ecosystems as reflected by critical loads exceedance. The model produces a set of emission, deposition and critical load maps in various spatial resolutions as well as maps of critical loads exceedances dynamically generated in response to various sulfur and nitrogen emission scenarios. Optionally, also the share of forest areas protected or unprotected against acidification is spatially presented. The model provides a decision tool to develop strategies aimed at the abatement of excess sulfur and nitrogen emissions. The present version of the model has been tailored to and implemented for Polish conditions. This model has been used to analyse the trends in impacts of acid deposition on Polish forest ecosystems.  相似文献   
62.
The aim of this experiment was to investigate whether the amount of Cu added to the diet of rats can be reduced without adversely affecting the antioxidant status of tissues and growth, and whether copper nanoparticles can be used for this purpose. For four weeks, four experimental groups of rats were fed diets with two dosages of added Cu (standard—6.5 or 3.25 mg/kg) in two forms (standard—CuCO3 or copper nanoparticles). Replacing the CuCO3 supplement with CuNPs resulted in a decreased lung weight and an increased Cu content in brain, kidney and lung, intensification of lipid peroxidation processes, and weakened antioxidant defence in the lungs and kidneys. This treatment also reduced the Cu content in heart, level of lipid oxidation in the liver and testes and improved antioxidant defence in the brain. Reducing the addition of Cu to the diet from 6.5 to 3.25 mg/kg reduced lung weight and increased lipid peroxidation in the liver, heart and lungs, and also weakened antioxidant defence in the lungs and testes. This treatment also weakened the lipid peroxidation process in the spleen, small intestine and brain and strengthened the antioxidant defence of the brain and kidneys. In conclusion, replacing CuCO3 with CuNPs and reducing the level of Cu in the diet of rats has a particularly unfavourable effect on the respiratory system, causing adverse changes in the lungs. However, these treatments have a clearly positive effect on the redox status of the liver and brain.  相似文献   
63.
The aim of the study was to attempt the detection of West Nile virus (WNV) in wild birds in Poland. Forty-eight species of 1912 wild birds were used for the investigations. The birds were derived from various locations in Poland from early spring till late autumn of the years 2009-2011. The brain samples were homogenised and cellular RNA was isolated. Two methods (RT-PCR and nested RT-PCR) were used. The presence of WNV RNA was not detected in the samples examined. Additionally, a short analysis of the epizootiological situation regarding the presence of WNV in Poland is presented.  相似文献   
64.
65.
Pairing, synapsis, and recombination are prerequisites for accurate chromosome segregation in meiosis. The phs1 gene in maize is required for pairing to occur between homologous chromosomes. In the phs1 mutant, homologous chromosome synapsis is completely replaced by synapsis between nonhomologous partners. The phs1 gene is also required for installation of the meiotic recombination machinery on chromosomes, as the mutant almost completely lacks chromosomal foci of the recombination protein RAD51. Thus, in the phs1 mutant, synapsis is uncoupled from recombination and pairing. The protein encoded by the phs1 gene likely acts in a multistep process to coordinate pairing, recombination, and synapsis.  相似文献   
66.
ABSTRACT

The research analyses the influence of the number of washings and different washing solutions, on the recovery of dry matter and protein in a preparation made from freshwater mussel Sinanodonta woodiana, (Lea, 1834). The study involved qualitative and quantitative characterisation of mussel protein preparation (MPP) obtained by electrophoretic separation and differential scanning calorimetry (DSC). The type of washing agent had the greatest influence on dry matter and protein content. Washing the homogenate with NaCl solutions and water was more effective on protein extraction than using only water. Two bands of proteins with molecular weights of 270–273 kDa and 42–43 kDa were characterized by the highest band intensity in electropherograms. The DSC analysis showed that on all denaturation curves of the samples there was one main peak of transformation ranging 56.69–62.94°C. The research revealed that washing homogenates with NaCl solutions caused the appearance of additional peaks at lower transformation temperatures, i.e. from 19.68°C to 36.45°C. The highest enthalpy value (4.53 Jg?1) was observed for the sample washed once NaCl solution and then water. The number of washings (1 or 2) and the use of a 0.5% NaCl solution or water were found to be the most favorable parameters for MPP production.  相似文献   
67.
The species of Salix herbacea L. and Salix lapponum L. are the rare relicts within the genus of Salix. With respect to their phylogeography, they are classified into the taxa of the Arctic-Alpine distribution. They can be found in the Arctic zone (Greenland, Scandinavia, Spitsbergen) as well as in such geographically separated areas as the mountains of lower latitudes like the Alps, the Sudetes or the Carpathians. Another species of willow occurring in the mountains of Europe, and more specifically on montane positions of the Balkan-Carpathian distribution is S. silesiaca. The aim of the study was to determine the severity of the diseases of the willows growing in selected locations in the Karkonosze Mountains. The research was conducted in the years 2014 and 2015 in the Kocio? ?omniczki [the ?omniczka Cirque] and the Wielki and Ma?y ?nie?ny Kocio?, [the Great and Small Snowy Cirques] at intervals of 4 weeks, from April to October. Field observations included the species of the genera Salix: S. herbacea, S. silesiaca and S. lapponum. Disease symptoms were identified with the percentage of infected plants at selected locations, as well as the percentage of infected leaves, recorded. In the course of the research, symptoms of rust caused by Melampsora epitea and M. alpina (S. herbacea and S. silesiaca), black spot blight caused by Rhytisma salicinum (S. silesiaca) and leaf spot, probably caused by a complex of fungal taxa (S. herbacea), were detected on the leaves of Salix spp. growing in post glacial cirques. During the study period, there were no disease symptoms on S. lapponum. A total of 13 species of fungi were isolated from the infected leaves of S. herbacea. In the first year, the highest share in the fungal assembly was taken by Penicillium notatum, followed by Alternaria alternata and an unidentified species of the genus Ceuthospora. In the second year of the research, Ceuthospora spp. and A. alternata predominated in the species assembly of fungi in the infected leaves of the herb willow.  相似文献   
68.
To investigate the role of non-hemagglutinating type 1 fimbriae in the pathogenesis of Salmonella Gallinarum, the isogenic mutant elaborating type 1 fimbriae with mannose-sensitive (MS) variant of the FimH adhesin from Salmonella Enteritidis and the mutant strain with no FimH expression were constructed. Their binding to chicken leukocytes in vitro and invasiveness in 1-day-old chicks were studied. Our results demonstrated that S. Gallinarum type 1 fimbriae with an endogenous variant of the FimH adhesin mediated mannose-resistant (MR) binding to avian leukocytes and did not bind to human epithelial cells. However, after allelic replacement of the FimH, mutated fimbriae with S. Enteritidis variant of the FimH adhesin bound to both cell types in a mannose-dependent manner. In chick model, S. Gallinarum expressing wild-type FimH variant colonized cecal tonsils and bursa of Fabricius more effectively and invaded the spleen and liver in greater numbers than S. Gallinarum fimH knockout strain or mutant expressing MS FimH variant from S. Enteritidis. The invasive potential of the latter was greatly reduced in chicks since no viable bacteria expressing MS variant of the adhesin could be recovered from intestinal lymphoid tissues or liver over a 6 days course of infection. Together, these results demonstrate that the S. Gallinarum type 1 fimbriae with the endogenous MR variant of the FimH protein increase systemic dissemination of S. Gallinarum and colonization of internal organs in chicks indicating the importance of these adhesive structures in the virulence of S. Gallinarum.  相似文献   
69.
The aim of this study was to verify the usefulness of the measurement of chosen cardiovascular activity parameters for examination of sex pheromones effects in male dogs. We evaluated the influence of the bitches' sexual pheromones (BSP) on heart rate (HR) with the use of a Holter monitor, and chosen parameters of blood flow in vessels of penis, testes and kidney, with color-coded and pulsed Doppler ultrasonography. We found that the BSP increased HR in all examined males even without showing any other signs of arousal. There were no changes in the RI (resistant index) and PI (pulsative index) in any trials during the pheromone presentation. The increase in blood flow intensity was noted in penile vessels but not in the testes and kidney. We concluded that measurement of flow intensity in the penis as well as the changes in heart rate as the male's reaction to the BSP can be useful in research concerning sex pheromones in dogs.  相似文献   
70.
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