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991.
992.
Anna Malmstrm 《Pedobiologia》2008,51(5-6):419-426
Forest fires markedly reduce the abundance of surface-dwelling soil animals; animal densities also decline in soil layers underlying the char layer. The aim of the present study was to determine lethal temperatures for different species within the more abundant microarthropod groups in boreal forests, namely Collembola, Protura, Mesostigmata and Oribatida. In the laboratory, forest soil humus containing naturally occurring microarthropods was heated in plastic bags to avoid desiccation. Each sample was heated to one of 11 different temperatures between 20 and 60 °C for 1, 4, or 12 h. At the 1-h exposure, 36 °C was the highest temperature tolerated before significant decreases in numbers were detected. The corresponding temperatures after 4- and 12-h exposures were 34 °C for Oribatida and 30–32 °C for Collembola, Protura and Mesostigmata, respectively. Individual species responded differently, and the most heat-tolerant species within Oribatida was Tectocepheus velatus (40 °C at 4-h exposure) while Friesea mirabilis and Mesaphorura sp. (36 °C at 4-h exposure) were the most tolerant within Collembola. During a forest fire, temperatures higher than those tolerated by the investigated groups and species may well be reached. 相似文献
993.
Peñalvo JL Adlercreutz H Uehara M Ristimaki A Watanabe S 《Journal of agricultural and food chemistry》2008,56(2):401-409
Lignans constitute a group of phytochemicals widely distributed in the human diet. Once ingested, most dietary lignans are metabolized by the gut microflora to enterolactone and enterodiol, also known as enterolignans. Together with isoflavones and coumestrol, enterolignans have been traditionally classified as phytoestrogens, plant-derived compounds that exhibit estrogen-like activity. In addition to a higher intake of vegetables, many studies have suggested that the presence of phytoestrogens in the Japanese diet is one of the factors that might explain the reduced incidence of certain chronic diseases in Japanese populations compared with Western countries. Being a vegetable-based diet, exposure to dietary lignans should be high, but to assess this exposure, a lignan food database is required. Stable isotope-dilution gas chromatography coupled with mass spectrometry was used to quantify six plant lignans in 86 food items commonly consumed in Japan. These data will complement the previous databases and most importantly expand the knowledge of occurrence of lignans in food to Eastern diets. 相似文献
994.
Sediments from 18 different road runoff detention systems, located on the Swedish West Coast, were assessed for their ecological hazard potential. Thirteen of the sites were detention ponds, three were manholes within the same sedimentation construction, and two were detention basins handling wash water from road tunnels. Sediments from all sites were analysed for a range of physico-chemical parameters and contaminants, and screened for acute toxicity using Hyalella azteca (sediment), Daphnia magna (elutriate), and Ceriodaphnia dubia (elutriate) as the test organisms, and for chronic toxicity using C. dubia as the test organism. The benthic fauna of the thirteen detention ponds was also studied. Sediment quality guidelines probable effect levels were exceeded for one or several contaminants at half of the sites, and one third revealed toxicity in some of the bioassays. Most of the detention ponds were dominated by tolerant taxa indicating low biological quality. Relationships between contaminant concentrations, toxicity in bioassays, and benthic fauna were, however, found to be weak. Extractable organic Zn, which was used as a tire wear marker, correlated with Zn, Cu, presumably from brake linings, and W, a common component of tire studs. The highest concentration, which was found in the manholes (14 mg kg?1 ds), corresponds to a tire wear concentration of 11 g kg?1 ds. The results of the present study have shown that traffic related contaminants accumulate in the studied runoff treatment systems, and, therefore, the maintenance of them is crucial in order to prevent contamination of surrounding waters. 相似文献
995.
Sweet potato cultivars respond differently to elevated tropospheric ozone concentrations of ca. 130 mug m (-3), 8 h a day for 4 weeks, which affects their selection for cultivation. In the first cultivar presented here, an adequate leafy vegetable supplier, the ozone load resulted in a shift of biomass to maintain the canopy at the expense of tuber development. Starch content of leaves was reduced, indicating an impairment of quality, but carotenoid content remained stable. The second cultivar may be grown for tuber production. Although the ratio tuber/plant remained stable under ozone, tuber yield and its starch content were significantly reduced. The lower starch content indicated a worse quality for certain industrial processing, but it is desirable for chip production. Elevated tropospheric ozone concentrations also influenced free amino acids and macronutrient contents of tubers, but these modifications were of minor significance for tuber quality in the second cultivar. 相似文献
996.
OBJECTIVE: To define the prevalence of overweight and obesity among school-aged children resident in mountain areas, rural areas and urban areas.Design, setting and subjectsThe sample (n = 12 832; 50.7% boys) included 9- and 11-year-old children of the Veneto Region of north-east Italy. Overweight and obesity status were determined using the International Obesity Task Force cut-off points for body mass index. The prevalence of overweight and obese subjects was calculated with a confidence interval of 95%. The Mantel-Haenszel method was used to compare the combined prevalence of overweight and obesity among children resident in mountain areas, rural areas and urban areas. RESULTS: Among boys the prevalence of overweight was 21.06%, while obesity prevalence was 5.92%; among girls overweight prevalence was 21.30%, while obesity prevalence was 5.15%. The prevalence was higher among 11-year-old boys (odds ratio (OR) = 1.19; 95% confidence interval (CI): 1.06-1.33) and 9-year-old girls (OR = 1.13; 95% CI: 1.01-1.26). Children resident in rural areas presented a higher risk of overweight and obesity compared with children resident in mountain areas (Mantel-Haenszel OR = 1.27; 95% CI: 1.13-1.42; chi2 = 17.55; P < 0.0001) and in urban areas (Mantel-Haenszel OR = 1.18; 95% CI: 1.07-1.31; chi2 = 10.39; P < 0.001). CONCLUSIONS: A relevant prevalence of overweight and obesity was found; the excess weight concerns one child in four. There are differences linked to different geographical areas that must be further investigated. 相似文献
997.
pH-Dependent radical scavenging capacity of green tea catechins 总被引:1,自引:0,他引:1
Muzolf M Szymusiak H Gliszczyńska-Swigło A Rietjens IM Tyrakowska B 《Journal of agricultural and food chemistry》2008,56(3):816-823
The effect of pH on the radical scavenging capacity of green tea catechins was investigated using experimental as well as theoretical methods. It was shown that the radical scavenging capacity of the catechins, quantified by the TEAC value, increases with increasing pH of the medium. Comparison of the pKa values to theoretically calculated parameters for the neutral and deprotonated forms indicates that the pH-dependent increase in radical scavenging activity of the catechins is due to an increase of electron-donating ability upon deprotonation. The data also reveal that the radical scavenging activity of the catechins containing the pyrogallol (or catechol) and the galloyl moiety over the whole pH range is due to an additive effect of these two independent radical scavenging structural elements. Altogether, the results obtained provide better insight into the factors determining the radical scavenging activity of the catechins and reveal that the biological activity of green tea catechins will be influenced by the pH of the surrounding medium or tissues. 相似文献
998.
Salvatore Vitale Michele Scotton Anna Maria Vettraino Andrea Vannini Anita Haegi Laura Luongo Marzia Scarpari Alessandra Belisario 《Forest Pathology》2019,49(1)
Forty‐eight isolates of Phytophthora cinnamomi obtained from common walnut were analysed according to their variability in growth at different temperatures, virulence, sensitivity to metalaxyl and in genomic DNA. Isolates were obtained from commercial common walnut orchards located in northern Italy and in southern France. Inter‐simple sequence repeat (ISSR) were analysed for the 49 isolates, 43 of which were Italian, 6 French; an isolate of the same species obtained from Viburnum spp. was used as an outgroup. ANOVA on phenotypic characters showed a significant impact of the geographic location of the orchard on isolate variability in terms of reaction to temperatures and aggressiveness. In turn, clustering obtained with UPGMA analysis on genetic data was almost exclusively dependant on isolate variability, nevertheless the 48 isolates seem to share a common variability that differentiates the group from the isolate from Viburnum spp. Correlation between phenotypic and genetic traits was not statistically significant. In conclusion, phenotypic variability like virulence seemed to be conditioned from geographic origin while the genetic variability of P. cinnamomi isolates from walnut was associated to the single genotype. 相似文献
999.
RNA-seq and single-cell genomic research emerge as an important research area in the recent years due to its ability to examine genetic information of any number of single cells in all living organisms.The knowledge gained from RNA-seq and single-cell genomic research will have a great impact in many aspects of plant biology.In this review,we summary and discuss the biological significance of RNA-seq and single-cell genomic research in plants including the single-cell DNA-sequencing,RNA-seq and single-cell RNA sequencing in woody plants,methods of RNA-seq and single-cell RNA-sequencing,single-cell RNA-sequencing for studying plant development,and single-cell RNA-sequencing for elucidating cell type composition.We will focus on RNA-seq and single-cell RNA sequencing in woody plants,understanding of plant development through single-cell RNAsequencing,and elucidation of cell type composition via single-cell RNA-sequencing.Information presented in this review will be helpful to increase our understanding of plant genomic research in a way with the power of plant single-cell RNA-sequencing analysis. 相似文献
1000.
Górnaś Paweł Czubinski Jaroslaw Rudzińska Magdalena Grygier Anna Ying Qian Chakradhari Suryakant Sahu Pravin Kumar Mišina Inga Urvaka Elise Patel Khageshwar Singh 《Plant foods for human nutrition (Dordrecht, Netherlands)》2019,74(1):91-98
Plant Foods for Human Nutrition - The seeds of nine species belonging to the Fabaceae family (Cassia alata, Cassia uniflora, Cassia obtusifolia, Cassia tora, Crotalaria albida, Crotalaria juncea,... 相似文献