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141.
The occurrence and phenotypic, and genotypic properties of 24 Staphylococcus isolates from canine dermatitis were investigated. The predominant staphylococcal species was Staphylococcus intermedius. The other species such as Staphylococcus chromogenes, Staphylococcus sciuri, Staphylococcus aureus, Staphylococcus saprophyticus, Staphylococcus epidermidis, and Staphylococcus capitis were only occasionally isolated. The study showed low level biochemical diversity among S. intermedius isolates. Resistance to antibiotics was frequently observed, with 87.5% of the isolates showing resistance to at least one drug. The most active antimicrobial agents against all staphylococci were amoxicillin/clavulanic acid, cephalexin and gentamicin. Resistance to carbenicillin, amoxicillin, ampicillin, cephadroxil, erythromycin, clinadmaycin and neomycin was common. No correlation was observed between antibiotic resistance and plasmid profile. PFGE analysis revealed a high degree of genetic polymorphism of S. intermedius, even among isolates collected in a restricted area over a short time.  相似文献   
142.

Context

Connectivity assessments typically rely on resistance surfaces derived from habitat models, assuming that higher-quality habitat facilitates movement. This assumption remains largely untested though, and it is unlikely that the same environmental factors determine both animal movements and habitat selection, potentially biasing connectivity assessments.

Objectives

We evaluated how much connectivity assessments differ when based on resistance surfaces from habitat versus movement models. In addition, we tested how sensitive connectivity assessments are with respect to the parameterization of the movement models.

Methods

We parameterized maximum entropy models to predict habitat suitability, and step selection functions to derive movement models for brown bear (Ursus arctos) in the northeastern Carpathians. We compared spatial patterns and distributions of resistance values derived from those models, and locations and characteristics of potential movement corridors.

Results

Brown bears preferred areas with high forest cover, close to forest edges, high topographic complexity, and with low human pressure in both habitat and movement models. However, resistance surfaces derived from the habitat models based on predictors measured at broad and medium scales tended to underestimate connectivity, as they predicted substantially higher resistance values for most of the study area, including corridors.

Conclusions

Our findings highlighted that connectivity assessments should be based on movement information if available, rather than generic habitat models. However, the parameterization of movement models is important, because the type of movement events considered, and the sampling method of environmental covariates can greatly affect connectivity assessments, and hence the predicted corridors.
  相似文献   
143.
Plant Foods for Human Nutrition - Bioactivity of mulberry has been widely described, but mostly related to its fruits, while studies with leaves are scarce. Herein, in this study leaves of two...  相似文献   
144.
This paper describes the use of cyclic voltammetry, photochemiluminescence (PCL), and spectrophotometric methods (TEAC and FCR reducing capacity) for the measurement of the antioxidant capacity of dark- and light-grown buckwheat sprouts. Moreover, the flavonoid profile of studied material is provided. Methanol extracts (80%) from ungerminated buckwheat grain and 6 and 8 DAS (days after seeding) sprouts were used. The 8 day germination period was sufficient to obtain good quality sprouts with completely removed pericarps. The ungerminated buckwheat grain contained only rutin, whereas in sprouts produced in dark or light, a high level of isoorientin, orientin, vitexin, rutin, and isovitexin was found. The flavonoid content in sprouts produced under light was almost 2 times higher than those of sprouts produced in the dark. The antioxidant capacity of light-grown sprouts was higher than that of dark-grown ones. The results from voltammetric experiments obtained for buckwheat seeds and 6 and 8 DAS sprouts harvested under dark or light conditions highly correlated with those obtained by PCL antioxidant capacity of water-soluble substances (PCL ACW) (r = 0.99), PCL antioxidant capacity of lipid-soluble substances (r = 0.99), TEAC (r = 0.99), and FCR reducing capacity (r = 0.99). The use of cyclic voltammetry, PCL ACW, and TEAC was fully applicable for the evaluation of the antioxidant capacity of buckwheat sprouts.  相似文献   
145.
Purpose

The objective of this study was to determine the long-term environmental changes induced by ancient landslide in the mountain fen. Attempts were made to demonstrate the progress of the soil cover restoration process about 200 years after the landslides and associated with changes in vegetation and soil microarthropod biodiversity and occurrence pattern associated with the restoration of soil cover.

Material and methods

The study covered mountain fen of the Caltho-Alnetum in the Babiogórski National Park in Outer Flysch Carpathians, Poland, where ancient landslide deposits are causing disturbance in fen hydrologic regime and over time related to various rate of fen area natural restoration processes. The drill test has been used to assess changes in layering and thickness of the fen soils. The following soil parameters, such as pH and total organic carbon content, were determined at each distinguish layer. The diversity and distribution pattern of soil microarthropods, represented by Collembola, was examined in two parts of the fen: restored and not-restored. The soil parameters, such as pH, electrical conductivity, total exchangeable base, total organic carbon, and nitrogen content, were determined in the soil samples simultaneously. The assessment of the vegetation structure recovery within studied mountain fen after landslide was referred to average parameters of the community completed for other natural mountain fens under the Caltho-Alnetum community. The research results were statistically verified.

Results and discussion

The test drillings showed that landslides change soil layering, site-specific soil properties of mountain fen such as chemistry (the statistically significant differences were noted only in the case of total organic carbon content), vegetation structure, and soil microarthropod communities. By changing site-specific conditions, landslides influence on the biodiversity and peatland ecosystems functioning.

Conclusion

Our results clearly demonstrate that the landslide itself initiated a complex and lengthy process of changes in biological aspects of peatlands including the biodiversity of the underground fauna and plant community. Soil microarthropod communities represented by Collembola can be used as a good indicator of mountain fen restoration process.

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146.
147.
The aim of this study was to evaluate the effect of the level of fat and selected fatty acids found in the milk of sows on the rearing of native breed piglets. Simultaneously, in order to improve the accuracy of the performed analyses, atomic absorption spectrometry was employed in the applied analytic methodology. The experimental animal material comprised 60 sows of the indigenous White Z?otnicka breed. Colostrum and milk were collected on the first and 14th days of lactation. In all, 240 samples were collected. The following parameters were determined in the course of the experiment: number and weight of piglets, body weight gains as well as deaths of piglets. A total of 1270 born piglets was subjected to investigations. The performed experiments demonstrated that, with the progress of the lactation period, the content of fat and saturated fatty acids (SFA) turned out to be statistically significant and showed a growing tendency. Fat increased by about 2% and palmitic acid (C16:0) increased most, that is by 5%. Linolic (C18:2) and linolenic (C18:3) acids revealed decreasing trends. Irrespective of the day of lactation, the level of unsaturated fatty acids (UFA) determined in sows' colostrum and milk was higher in comparison with that of SFA, and the UFA to SFA ratio ranged from 1.84% to 1.33%. Proportions of n‐6 to n‐3 fatty acids were determined at the level of about 1.6:1.0 in the colostrum and 1.3:10 in milk. The highest daily body weight gains were recorded in the case of piglets derived from sows with the highest fat level – 294 g, while in the case of stearic acid (C18:0), the smaller its concentration in the colostrum and milk of the experimental sows, the better body weight gains of piglets – 262 g. At the same time, stearic acid (C18:0) was found to exert a statistically significant effect on piglet mortality at the level of P ≤ 0.05. Its highest concentration caused the highest proportion of deaths among piglets ‐ 16.23%. The performed analysis of correlations that occurred between fat, fatty acids and traits associated with piglet rearing confirmed that linolic acid (C18:2; n‐6) was highly significantly correlated with piglets' body weights (r = 0.456**) and was negatively correlated with piglets' deaths (r = ?0.312). On the other hand, fat revealed correlation with body weight gains of piglets (r = 0.333*_ and a negative correlation with deaths of piglets (r = ?0344*). Recapitulating, the results of the performed experiments revealed that differences in the levels of fat and fatty acids found in sows' colostrum and milk influenced results of piglet rearing. Together with the increase in the content of fat and UFA in sows' colostrum and milk, piglets were characterized by the best body weight, growth rate, as well as by small mortality.  相似文献   
148.
Wastewater samples originating from an explosives production plant (3,000 mg N l−1 nitrate, 4.8 mg l−1 nitroglycerin, 1.9 mg l−1 nitroglycol and 1,200 mg l−1 chemical oxygen demand) were subjected to biological purification. An attempt to completely remove nitrate and to decrease the chemical oxygen demand was carried out under anaerobic conditions. A soil isolated microbial consortium capable of biodegrading various organic compounds and reduce nitrate to atmospheric nitrogen under anaerobic conditions was used. Complete removal of nitrates with simultaneous elimination of nitroglycerin and ethylene glycol dinitrate (nitroglycol) was achieved as a result of the conducted research. Specific nitrate reduction rate was estimated at 12.3 mg N g−1 VSS h−1. Toxicity of wastewater samples during the denitrification process was studied by measuring the activity of dehydrogenases in the activated sludge. Mutagenicity was determined by employing the Ames test. The maximum mutagenic activity did not exceed 0.5. The obtained results suggest that the studied wastewater samples did not exhibit mutagenic properties.  相似文献   
149.
150.
Three C(13)-norisoprenoid compounds, 3,6,9-trihydroxymegastigma-4,7-diene (6), 3,4,9-trihydroxymegastigma-5,7-diene (4), and the actinidols (8), have all been synthesized and subjected to acid hydrolysis. All three were shown to generate (E)-1-(2,3,6-trimethylphenyl)buta-1,3-diene (1) under wine conservation conditions. At 45 degrees C, approximately 4000-5000 ng/L of 1 was formed from 1.0 mg/L of precursor, after 173 days, while at 25 degrees C more wine-like amounts (200-600 ng/L) were observed. A glucoside, 4,5-dihydrovomifoliol-C(9)-beta-d-glucopyranoside (9b), was isolated from grapevine leaves by multilayer coil countercurrent chromatography (MLCCC), and its stereochemistry was deduced as being (5R, 6S, 9R) by NMR and CD spectroscopy. Hydrolysis of this glucoside produced 1, but in quantities insufficient to account for the levels observed in wine.  相似文献   
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