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The dynamics of stomatal opening and closure had to date been ascribed largely to the K(+)-fluxes and cell wall elasticity. Using protoplasts of guard cells of Vicia faba as model system, we document convincing first hand evidence a that lipid phase alterations could regulate ABA-induced closure of stomates and its reversal by umbelliferone. Backed up by the presence of plasmalemma-located ABA-receptor in guard cells, a novel theory could be put forth explaining guard cell opening and closure mediated by hormone induced reconfiguration via a probable lipid-protein lattice modification. The phase reversal of the plasmalemma by umbelliferone is postulated to be through modified hormone receptor complex structure, which is yet to be substantiated.  相似文献   
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Pus samples obtained from 109 patients with liver abscess were examined by NMR spectroscopy. To our knowledge this is the first report on metabolic profiling of liver abscesses. Fifty metabolites were identified by combination of one (1D) and two-dimensional (2D) NMR spectra. Metabolic derangements were evaluated for differentiation between amoebic (ALA) and pyogenic liver abscess (PLA). The NMR results indicate that aspartate, asparagine and galactose, integral components of lipoproteophophoglycans (LPG) of the cell wall of Entamoeba histolytica are metabolic biomarkers of ALA. On the other hand, acetate, propionate, butyrate, succinate and formate, the fermentation products the facultative anaerobes are significantly prevalent in PLA. The NMR based metabolic profile of ALA and PLA are evaluated taking polymerase chain reaction (PCR) and bacterial culture as gold standard method. However, when NMR results were compared with culture and PCR methods, a correct diagnosis of 94.11% in ALA (n?=?85) and 100% in PLA (n?=?10) cases were observed. NMR spectroscopy in conjunction with PCR and culture can expedite in differentiating ALA from PLA.  相似文献   
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Many wildlife species suffer from human–wildlife conflict, especially crop-raiding. Long-term analyses of mortality patterns are needed to assess the efficacy of management strategies that address this issue. We report mortality patterns from necropsies of 498 Asian elephants from 2009–2018 in an area of northwestern Sri Lanka. Deaths were lowest in July and highest in October, a period of peak crop availability. Most (about 70%) deaths were human-related, and males were killed in these incidents more frequently than females. As gunshot deaths decreased, other forms of human-related deaths increased. Additionally, causes of death differed between districts, with more intentional human-related mortality observed in the district with the highest percent of protected land. These results highlight the importance of understanding the long-term spatial and temporal variation in wildlife mortality to effectively address human–wildlife conflict. © 2021 The Wildlife Society.  相似文献   
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Manipulations of the environments of captive nonhuman primates often have welfare consequences to the animals, including behavioral effects, and for certain manipulations, physiological effects as well. The processes of transporting, relocating, and acclimatizing nonhuman primates across facilities represent manipulations that are likely to have welfare, behavioral, and physiological consequences to the relocated animals. Seventy-two chimpanzees were relocated from the Primate Foundation of Arizona (PFA) in Arizona to the Keeling Center (KCCMR) in Texas. Animals were transported for approximately 21 h in single cages in a USDA-approved, climate-controlled trailer. Chimpanzees were weighed, anesthetized, and blood samples were collected 1) immediately prior to departure from PFA, 2) immediately upon arrival at the KCCMR, and 3) at additional time point(s) between 3 and 12 weeks after arrival at the KCCMR. Chimpanzees were quarantined in familiar pairs or social groups for 60-90 days at the KCCMR. Blood samples were analyzed for hematological and clinical chemistry parameters and compared across time points. In addition, samples from a subset of animals were assayed for cell-mediated immune parameters. Comparisons of the data obtained just prior to transport, to the data obtained immediately upon arrival, revealed numerous statistically significant differences in hematological, clinical chemistry, and immunological parameters. Some of these were indicative of stress, and thus, changes in welfare state, although many remained within the published normal ranges for chimpanzees. Additional analyses showed that many of the clinical chemistry values collected 3 to 12 weeks after arrival at the KCCMR had returned to pre-transport values. In contrast, of the cell-mediated immune parameters that were affected by transport and relocation, few had returned to pre-transport levels 8 weeks after transport, and three of the four hematology variables analyzed had not returned to pre-transport levels 12 weeks after transport. Comparisons of body weights before and immediately after transport revealed that animals lost an average of 2.5 kg during the 21-h transport, a statistically significant reduction that some animals never regained. These results demonstrate that transport and relocation affect a variety of physiological parameters with potential welfare implications and that some of these effects last as long as 3 months. These findings have important implications for the welfare and use of recently transported nonhuman primates, especially chimpanzees, in biomedical research. In order to allow animals to adapt to their new surroundings and to prevent unwanted confounds from influencing experiments, sufficient time must be provided after transport for chimpanzees to acclimatize.  相似文献   
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