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51.
Ren  Xinwei  Tang  Jingchun  Wang  Lan  Liu  Qinglong 《Plant and Soil》2021,462(1-2):561-576
Plant and Soil - To investigate the effects of polystyrene microplastics (PS-beads) on the soil properties, photosynthesis of Flowering Chinese cabbage, the rhizosphere microbial community and...  相似文献   
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Emerging infectious diseases threaten a wide diversity of animals, and important questions remain concerning disease emergence in socially structured populations. We developed a spatially explicit simulation model to investigate whether—and under what conditions—disease-related mortality can impact rates of pathogen spread in populations of polygynous groups. Specifically, we investigated whether pathogen-mediated dispersal (PMD) can occur when females disperse after the resident male dies from disease, thus carrying infections to new groups. We also examined the effects of incubation period and virulence, host mortality and rates of background dispersal, and we used the model to investigate the spread of the virus responsible for Ebola hemorrhagic fever, which currently is devastating African ape populations. Output was analyzed using regression trees, which enable exploration of hierarchical and non-linear relationships. Analyses revealed that the incidence of disease in single-male (polygynous) groups was significantly greater for those groups containing an average of more than six females, while the total number of infected hosts in the population was most sensitive to the number of females per group. Thus, as expected, PMD occurs in polygynous groups and its effects increase as harem size (the number of females) increases. Simulation output further indicated that population-level effects of Ebola are likely to differ among multi-male–multi-female chimpanzees and polygynous gorillas, with larger overall numbers of chimpanzees infected, but more gorilla groups becoming infected due to increased dispersal when the resident male dies. Collectively, our results highlight the importance of social system on the spread of disease in wild mammals.  相似文献   
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We isolated a recombinant H9N2 avian influenza virus (AIV) from fresh egret feces in the Ardeidae protection region of the Dongting Lake wetland area in China, and it was designated A/Egret/Hunan/1/2012(H9N2). This is the first report of isolating H9N2 AIV from wild birds in the Dongting Lake wetland. Its eight gene segments are generated by reassortment of gene segments of different AIV subtypes. These results are helpful for understanding the epidemiology and evolution of AIV in wild birds during migration.  相似文献   
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Islet transplantation has become a promising treatment in the therapy of type 1 diabetes. Its function improvement, after isolation and before transplantation, is crucial because of their loss both in number and function of islets after isolation procedures. Trace elements sodium orthovanadate (SOV) and sodium molybdate (SM), as well as medicinal plant Teucrium polium L. (TP), showed and possessed high beneficial antioxidative potential and even hypoglycemic properties via their effect on islets. We evaluated the effect of these components in combination on cultured islet function in order to improve pancreatic islet transplantation. Rat pancreatic islets were cultured for 24 h then incubated with different concentrations of TP (0.01 and 0.1 mg/mL) alone and in combination with SOV (1 mM) or SM (1 mM). Insulin concentration in buffer media was measured as islet secretory function. Administration of TP (0.01 mg/mL), SM, and SOV alone or in combination with each other significantly increased insulin secretion at high glucose concentration (16.7 mM); insulin secretion was significantly greater in the group containing both TP and SM than other treated groups (p < 0.05). The combination of the mentioned trace elements especially molybdate with TP could improve islet cells function before transplantation.  相似文献   
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The Wageningen Delivery of Functionality symposium covered all aspects involved with food structural design to arrive at high-quality foods which meet demanding customer expectations and regulatory requirements. The symposium integrated aspects from the structural organization of foods at molecular and supramolecular scales to dedicated techniques required to describe and visualize such structures, the gastro-intestinal events and how to model these in a laboratory setting, and finally the impact those food structures and ingredients have on the consumer’s physiology and on the human perception. As an interdisciplinary platform, bringing together more than 160 researchers from academia and industry, the symposium meanwhile fulfills an important role in the food science community.  相似文献   
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Evergreen boreal plant species express high variability in their leaf traits. It remains controversial whether this within-species variability is constrained to the same leaf trait relationships as has been observed across species. We sampled leaves of three boreal evergreen woody species along a latitudinal gradient (from 57o56′N to 69o55′N). Leaf longevity (LL) of Pinus sylvestris L. and Vaccinium vitis-idaea L. correlated negatively with mean annual air temperature (MAT), whereas the LL of Ledum palustre L. was not affected by MAT. V. vitis-idaea and L. palustre had a negative relationship between leaf mass per area (LMA) and MAT. In P. sylvestris, the LMA–MAT relationship was positive. A negative correlation between LL and LMA was significant only for P. sylvestris. Leaf nitrogen concentration was positively related to leaf phosphorus concentration in all three species. Leaf potassium concentration was related to nitrogen concentration only in L. palustre, and to phosphorus concentration in P. sylvestris and L. palustre. Our results demonstrate that although within the studied species the variation in some of the leaf traits may have the same degree as interspecific variation, there is no such intercorrelation of leaf traits within the studied species as has been observed across species.  相似文献   
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