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1.
Application of hydrophilic polymers composed of cross‐linked polyacrylate can improve soil water‐holding capacity and accelerate the restoration of post‐mining substrates. In this work, we studied the persistence of a polyacrylate polymer incorporated into a soil and its impact on plant nutrients at a reclamation site of former lignite mining in Lusatia (Germany). In contrast to autumn application, the incorporation of the polymer enhanced the sequestration of plant‐derived carbon in the soil, which was reflected by a significant increase in the concentration of a lignin marker. Attenuated total reflexion–Fourier transform infrared spectra (ATR‐FTIR) and total elemental contents in the applied polymer suggested an intensive cation exchange between the polymer framework and the soil‐forming substrate. In addition, there was an enrichment of carbonaceous material, which seems to reduce the swelling and thus the water‐holding capacity of the cross‐linked polyacrylate. Conversely, this process protected the polymer structure from rapid decomposition.  相似文献   
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The mucosa of the intestine and oviduct of hens are susceptible to pathogens. Pathogenic infections in the mucosal tissues of laying hens lead to worsened health of the host animal, decreased egg production, and bacterial contamination of eggs. Therefore, better understanding of the mechanisms underlying mucosal barrier function is needed to prevent infection by pathogens. In addition, pathogen infection in the mucosal tissue generally causes mucosal inflammation. Recently, it has been shown that inflammation in the oviduct and intestinal tissue caused by disruption of the mucosal barrier function, can affect egg production. Therefore, it is vitla to understand the relationship between mucosal barrier function and egg production to improve poultry egg production. This paper reviews the studies on (1) oviductal mucosal immune function and egg production, (2) intestinal inflammation and egg production, and (3) improvement of mucosal immune function by probiotics. The findings introduced in this review will contribute to the understanding of the mucosal barrier function of the intestine and oviduct and improve poultry egg production in laying hens.  相似文献   
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The effects of soil water availability on suberin lamellae formation in the endodermis and exodermis and the occurrence of cell wall thickening in the cortex in red bayberry (Myrica rubra Sieb. et Zucc.) tree roots were examined during tissue aging. For several months, red bayberry trees were grown in small baskets under dry, normal, and waterlogged soil water conditions. Transverse sections of roots from 5 mm from the tip to the basal portion were stained with several staining solutions and the cell structure was observed. Root anatomical development was significantly changed by soil water conditions. The suberin lamellae in the endodermis formed later in plants grown under dry conditions than in those grown under waterlogged conditions. Cell wall thickening in the cortex near the endodermis was promoted by drought, but apparently not by waterlogged conditions.  相似文献   
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Melatonin has been reported to improve the in vitro development of embryos in some species. This study was conducted to investigate the effect of melatonin supplementation during in vitro maturation (IVM) and development culture on the development and quality of porcine embryos. In the first experiment, when the in vitro fertilized embryos were cultured with different concentrations of melatonin (0, 10, 25 and 50 ng/ml) for 8 days, the blastocyst formation rate of embryos cultured with 25 ng/ml melatonin (10.7%) was significantly increased (p < 0.05) compared to the control embryos cultured without melatonin (4.2%). The proportion of DNA‐fragmented nuclei in blastocysts derived from embryos cultured with 50 ng/ml melatonin was significantly lower (p < 0.05) than that of embryos cultured without melatonin (2.1% vs 7.2%). In the second experiment, when oocytes were cultured in the maturation medium supplemented with different concentrations of melatonin (0, 10, 25 and 50 ng/ml), fertilized and then cultured with 25 ng/ml melatonin for 8 days, there were no significant differences in the rates of cleavage and blastocyst formation among the groups. However, the proportions (2.7–5.4%) of DNA‐fragmented nuclei in blastocysts derived from oocytes matured with melatonin were significantly decreased (p < 0.05) compared to those (8.9%) from oocytes matured without melatonin, irrespective of the concentration of melatonin. Our results suggest that supplementation of the culture media with melatonin (25 ng/ml) during IVM and development has beneficial effects on the developmental competence and quality of porcine embryos.  相似文献   
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The movements of 28 adult chum salmon, Oncorhynchus keta (Walbaum) tagged with electromyogram (EMG) transmitters were tracked along the Toyohira river, Hokkaido, Japan, in October of 2007 and 2008 to investigate and evaluate the upstream migratory behavior through the protection bed and fishway of ground sills. The approach time of fish that ascended successfully through the protection bed and fishway was shorter than that of unsuccessful fish. The unsuccessful fish were observed to swim in currents with high water velocity and shallow water depth at swimming speeds that exceeded their critical swimming speed (U crit) during the approach to these structures. In consequence, unsuccessful fish frequently alternated between burst and maximum sustained speeds without ever ascending the fishway, and eventually became exhausted. It is important that fishway are constructed to enable chum salmon to find a passage way easily, so that they can migrate upstream rapidly without wasting excessive energy.  相似文献   
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不同氮素施用量对葡萄叶、枝、根碳水化合物含量的影响   总被引:4,自引:0,他引:4  
本试验用500ml塑料育苗盆定植一年生葡萄扦植苗,研究不同氮素施用量对地上部和地下部生长及碳水化合物含量的影响,并对根尖细胞构造进行了探讨,结果表明:地上部生长量,干物重,叶面积在N-300区最大;全叶绿素含量随氮素施用量的增加而增加,叶淀粉,全糖含量随氮素施用量的增加而降低,枝条和根的淀粉含量在N-75区和N-150区最高,全糖含量在N-150区和N-300区最高,在N-900区最低。生长越旺盛的植株,白色根越多,氮素施用量过多时出现黑色根增多的倾向。  相似文献   
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The objective of the research was to identify QTL affecting the number of vertebrae in swine, one of the major determining factors of growth and body composition. Previously, we reported a QTL for the number of vertebrae located on SSC1qter (terminal band of the q arm of SSC 1) in an F2 family produced by crossing a G?ttingen miniature male with two Meishan females. Eight other swine families were subsequently produced by crosses between different breeds of European, Asian, and miniature pigs. In these families, the QTL on SSC1qter for the number of vertebrae was detected. Unlike the Asian alleles, all European alleles in this study had the effect of increasing the number of vertebrae by 0.44 to 0.69 and acted additively without dominance. The G?ttingen miniature sire, for which we previously reported a smaller additive effect, seemed to be heterozygous at the QTL. In the present study, another QTL was found for the number of vertebrae on SSC7. This QTL was not fixed in the European pigs used as parents in our experimental families, and some of the European alleles increased the number of vertebrae. A half-sib analysis confirmed that this QTL was segregating in a commercial Large White population. Analysis in an F2 family in which the parental pigs were fixed for alternative alleles revealed that the effects of the QTL on SSC1 and on SSC7 were additive and similar in size. The two QTL acted independently without epistatic effects and explained an increase of more than two vertebrae.  相似文献   
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