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951.
E. Franců J. Schwarzbauer R. Lána D. Nývlt S. Nehyba 《Water, air, and soil pollution》2010,209(1-4):81-91
Results of a comprehensive study are presented on the spatial and depth-related distribution of persistent organic pollutants (POPs) in sediments of the Brno reservoir, Czech Republic. Based on sedimentological observations, three major historic phases were identified related to the evolution of the depositional environment, flow rate, and material input. Data on organic carbon, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and organochlorine pesticides showed specific distribution patterns in a 3-m-deep core. The analysis of the depth trends of the geochemical data combined with sedimentology made it possible to distinguish between remote sources of the pollutants, early weathering alterations of POPs, transport by river associated with organic matter as sorbent on one hand, and local sources weakly related to lithology on the other hand. The integrated sedimentological and environmental geochemical archive provided an improved dynamic view of the pollution in historical terms. 相似文献
952.
K. Zemanová T. Picek J. Dušek K. Edwards H. Šantrůčková 《Water, air, and soil pollution》2010,207(1-4):39-48
Two horizontal constructed wetlands with subsurface flow (CWs) of different age were monitored in a 2-year study. One of the CWs was new, while the second one had been in operation for 5 years in the first year of study. Transformations of C, P, and N were measured in each CW in the substrate of the vegetated bed under both aerobic and anaerobic conditions, and their rates were compared. C was mineralized in both CWs under both aerobic and anaerobic conditions, but mineralization rates differed between the CWs; they were cca ten times higher in the established CW compared to the new CW. Dissolved reactive phosphorus (DRP) was immobilized under aerobic conditions but was mobilized under anaerobic conditions. DRP transformation was cca five times faster in the established CW. Nitrification occurred under aerobic conditions at similar rates in both CWs. NH4 + concentration decreased under both aerobic and anaerobic conditions, but there was large variability. The age of the CW affected C mineralization rates and DRP immobilization rates under aerobic conditions and mobilization rates under anaerobic conditions; they increased as the CWs maturated, while no effect of CW age was observed on nitrogen removal rates. 相似文献
953.
Genes for resistance to powdery mildew in European barley cultivars registered in the Czech Republic from 2011 to 2015 下载免费PDF全文
Antonín Dreiseitl 《Plant Breeding》2017,136(3):351-356
Barley (Hordeum vulgare) is cultivated on 49.1 million hectares worldwide with 50.2% of the area located in Europe. Powdery mildew, caused by Blumeria graminis f. sp. hordei (Bgh), occurs wherever barley is grown. Cultivar resistance plays an important role in global barley production, especially in parts of Europe where high concentrations of both spring and winter types are grown. The aim of this report was to postulate specific resistance genes in barleys from nine European countries registered in the Czech Republic from 2011 to 2015. Thirty‐five spring cultivars and 27 winter barleys were tested with 56 diverse Bgh isolates. Twenty‐five known resistance genes were postulated, and unknown genes were detected in Sandra, Saturn and Zeppelin. Unidentified specific resistance genes were also present in winter hybrids Hobbit and Wootan. Spring cultivars Arthur and Francin consisted of three and two genotypes, respectively. Resistance gene mlo was present in 26 spring cultivars, and the proportion of cultivars with this gene increased from 62.9% in 2006–2010 to 75.7% in 2011–2015. The gene Mlp1 was identified for the first time in German winter cultivar Saturn. Five spring cultivars registered in Slovakia were included in the tests. All the cultivars that were tested contained one or more specific resistance genes to powdery mildew. Adaptability of the pathogen and possibilities for breeding winter barleys are discussed. 相似文献
954.
de Oliveira Silva Alan Savi Daiani Cristina Raiser Paulo Henrique Schueda Gonçalves Fabrício Packer Kava Vanessa Galli-Terasawa Lygia Vitória Glienke Chirlei 《植物病害和植物保护杂志》2017,124(1):73-80
Journal of Plant Diseases and Protection - Citrus black spot (CBS) is a disease caused by the fungus Phyllosticta citricarpa that is associated with significant yield losses. The pathogen forms... 相似文献
955.
Summary A simple assay for detection of tobacco rattle virus in infected tubers involving RT-PCR was developed. The assay detected
a wide range of strains, including nonparticle NM variants. RNA extraction methods were compared, and a simple method was
found to give reliable results. The method enabled detection of at least 1 ng of tobacco rattle particles in 100 mg tuber
extract. 相似文献
956.
Saulo Petinatti Pavarini Danilo Carloto Gomes Marcele Bettim Bandinelli Flademir Wouters Luciana Sonne David Driemeier Cláudio Estêv?o Farias da Cruz 《Acta veterinaria Scandinavica》2013,55(1):7
Chronic cardiac insufficiency was associated with a malignant peripheral nerve sheath tumor in a cow. An eight-year-old cow developed a progressive condition (over a period of three months) characterized by an enhanced abdominal volume, reluctance to move, a positive jugular pulse, watery diarrhea and death. At necropsy, moderate subcutaneous edema and an enhanced hepatic lobular pattern were observed. A 23x20x11 cm firm, grayish-white mass adhered to and infiltrated the right atrium. Multiple firm, yellowish-white nodules of 0.5 to 12 cm in diameter were diffusely scattered in the epicardium and parietal pericardium. Histologically, the tumor was poorly circumscribed with foci of infiltration of the myocardium. The neoplastic cells had two major histologic patterns, Antoni types A and B. Within occasional foci, pleomorphic cells with an epithelioid appearance were present in addition to multinucleated cells with periodic acid Schiff (PAS)-positive cytoplasmic globules. Foci of cartilaginous and granular differentiations were interspersed among the neoplastic cells. Multiple vessels presented wall hyalinization and tumoral embolus. Large necrotic foci with mineralization and cholesterol clefts were also observed. Immunohistochemically, the tumor was positive for S100 protein, vimentin and neuron-specific enolase labeling. 相似文献
957.
Triticum urartu is a wild diploid wheat identified as donor of the A genome in the durum and bread wheats. This species has its natural distribution
zone in the Fertile Crescent. Nine populations from this zone (five Lebanese and four Turkish) were analysed for the variation
in the loci coding of endosperm storage proteins: glutenins (Glu-A
u
1 and Glu-A
u
3) and gliadins (Gli-A
u
1 and Gli-A
u
2). Up to 10 alleles for the Glu-A
u
1 locus, 16 for the Glu-A
u
3 locus, 15 for the Gli-A
u
1 locus and 18 for the Gli-A
u
2 locus were found. The Turkish populations showed greater diversity than the Lebanese populations, distributing mainly within
populations, whereas the inverse process takes place for the Lebanese populations. The values of the genetic diversity indicated
that, although these materials showed high level of variability, exist a real risk of genetic erosion. 相似文献
958.
Granado-Lorencio F Donoso-Navarro E Sánchez-Siles LM Blanco-Navarro I Pérez-Sacristán B 《Journal of agricultural and food chemistry》2011,59(21):11819-11824
Bioactive compounds are used in the design and development of new food products with potential health benefits, although little is known regarding their bioavailability and interactions. This study assessed the stability, in vitro bioaccessibility, and human bioavailability of β-cryptoxanthin from β-cryptoxanthin-rich drinks with and without added phytosterols developed for this purpose. The developed drinks showed no difference in the content of β-cryptoxanthin, and they were stable over 6 months. In vitro, hydrolysis of β-cryptoxanthin esters and the amount of free β-cryptoxanthin at duodenal and micellar phases were similar regardless of the presence of phytosterols. In the human study, the daily intake provoked significant increments of β-cryptoxanthin in serum regardless of the type of the drink. In conclusion, in vitro and in vivo human studies have shown that the bioavailability of β-cryptoxanthin is not significantly affected by the presence of phytosterols when they are simultaneously supplied in a drink. 相似文献
959.
L. Tusell P. Pérez‐Rodríguez S. Forni D. Gianola 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2014,131(2):105-115
Predictive ability of yet‐to‐be observed litter size (pig) grain yield (wheat) records of several reproducing kernel Hilbert spaces (RKHS) regression models combining different number of Gaussian or t kernels was evaluated. Predictive performance was assessed as the average (over 50 replicates) predictive correlation in the testing set. Predictions from these models were combined using three different types of model averaging: (i) mean of predicted phenotypes obtained in each model, (ii) weighted average using mean squared error as weight or (iii) using the marginal likelihood as weight. (ii) and (iii) were obtained in a validation set with 5% of the data. Phenotypes consisted of 2598, 1604 and 1879 average litter size records from three commercial pig lines and wheat grain yield of 599 lines evaluated in four macro‐environments. SNPs from the PorcineSNP60 BeadChip and 1447 DArT markers were used as predictors for the pig and wheat data analyses, respectively. Gaussian and univariate t kernels led to same predictive performance. Multikernel RKHS regression models overcame shortcomings of single kernel models (increasing the predictive correlation of RKHS models by 0.05 where 3 Gaussian or t kernels were fitted in the RKHS models simultaneously). None of the proposed averaging strategies improved the predictive correlations attained with single models using multiple kernel fitting. 相似文献
960.
The purpose of this study was to determine whether intravaginal prostaglandin F2 alpha (PGF2 alpha) would be effective for the treatment of metritis or pyometra in the bitch. Seventeen bitches with metritis or pyometra were treated with PGF2 alpha. Prostaglandin F2 alpha (150 micrograms/kg body weight) was administered once or twice daily by infusing 0.3 ml per 10 kg body wt into the vaginal lumen. Bitches were also treated with amoxicillin (15 mg/kg body wt/48 h) and/or gentamicin (4 mg/kg body wt/day) administered as intramuscular (i.m.) injections. Fifteen bitches were treated successfully with intravaginally administered PGF2 alpha for 3 to 12 days and with intramuscularly administered antibiotics for 4 to 12 days. Success of treatment was judged by cessation of vaginal discharge, the absence of fluid in the uterus as determined by ultrasonography, and the overall health status of the animal. As two bitches with pyometra showed clinical deterioration in spite of medical treatment, ovariohysterectomy was performed after the first and the second treatment, respectively. No side effects (salivation, vomiting, diarrhoea, hyperpnoea, ataxia, urination, anxiety, pupillary dilatation followed by contraction) were observed after PGF2 alpha treatment. The disease did not recur during the subsequent oestrous cycles within 12 months after the initial treatment. The results demonstrate that intravaginal administration of PGF2 alpha was effective in 13 dogs (86.6%) with metritis or pyometra, and caused no side effects. Although the study was based on a relatively small number of cases, it is concluded that prostaglandin F2 alpha can be a useful means of treating bitches with metritis or pyometra. However, in severe cases of pyometra ovariohysterectomy is needed. 相似文献