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81.
Global climate change may become one of the most pressing challenges to Pacific Salmon conservation and management for southeast Alaska in the 21st Century. Predicted hydrologic change associated with climate change will likely challenge the ability of specific stocks to adapt to new flow regimes and resulting shifts in spawning and rearing habitats. Current research suggests egg-to-fry survival may be one of the most important freshwater limiting factors in Pacific Salmon''s northern range due to more frequent flooding events predicted to scour eggs from mobile spawning substrates. A watershed-scale hydroclimatic sensitivity index was developed to map this hypothesis with an historical stream gauge station dataset and monthly multiple regression-based discharge models. The relative change from present to future watershed conditions predicted for the spawning and incubation period (September to March) was quantified using an ensemble global climate model average (ECHAM5, HadCM3, and CGCM3.1) and three global greenhouse gas emission scenarios (B1, A1B, and A2) projected to the year 2080. The models showed the region''s diverse physiography and climatology resulted in a relatively predictable pattern of change: northern mainland and steeper, snow-fed mountainous watersheds exhibited the greatest increases in discharge, an earlier spring melt, and a transition into rain-fed hydrologic patterns. Predicted streamflow increases for all watersheds ranged from approximately 1-fold to 3-fold for the spawning and incubation period, with increased peak flows in the spring and fall. The hydroclimatic sensitivity index was then combined with an index of currently mapped salmon habitat and species diversity to develop a research and conservation priority matrix, highlighting potentially vulnerable to resilient high-value watersheds. The resulting matrix and observed trends are put forth as a framework to prioritize long-term monitoring plans, mitigation experiments, and finer-scale climate impact and adaptation studies. 相似文献
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Fazal Shirazi Dimitrios Farmakiotis Yuanqing Yan Nathaniel Albert Do Kim-Anh Dimitrios P. Kontoyiannis 《PloS one》2014,9(9)
In an experimental model of obesity and hyperglycemia in Drosophila melanogaster we studied the effect of diet modification and administration of metformin on systemic infection with Rhizopus, a common cause of mucormycosis in diabetic patients. Female Wt-type Drosophila flies were fed regular (RF) or high-fat diet (HFD; 30% coconut oil) food with or without metformin for 48 h and then injected with R. oryzae. Survival rates, glucose and triglyceride levels were compared between 1) normal-weight flies (RF), 2) obese flies (HFD), 3) obese flies fed with RF, 4) flies continuously on HFD + metformin, 5) flies fed on HFD + metformin, then transferred to RF, and 6) obese flies administered metformin after infection. Glucose levels were compared across groups of non-infected flies and across groups of infected flies. Survival was significantly decreased (P = 0.003) in obese flies, while post-infection glucose levels were significantly increased (P = 0.0001), compared to normal-weight flies. Diet and administration of metformin led to weight loss, normalized glucose levels during infection, and were associated with decreased mortality and tissue fungal burden. In conclusion, diet and metformin help control infection-associated hyperglycemia and improve survival in Drosophila flies with mucormycosis. Fly models of obesity bear intriguing similarities to the pathophysiology of insulin resistance and diabetes in humans, and can provide new insights into the pathogenesis and treatment of infections in obese and diabetic patients. 相似文献
84.
Regulator of G-protein signaling 18 (RGS18) is a GTPase-activating protein that turns off Gq signaling in platelets. RGS18 is regulated by binding to the adaptor protein 14-3-3 via phosphorylated serine residues S49 and S218 on RGS18. In this study we confirm that thrombin, thromboxane A2, or ADP stimulate the interaction of RGS18 and 14-3-3 by increasing the phosphorylation of S49. Cyclic AMP- and cyclic GMP-dependent kinases (PKA, PKG) inhibit the interaction of RGS18 and 14-3-3 by phosphorylating S216. To understand the effect of S216 phosphorylation we studied the phosphorylation kinetics of S49, S216, and S218 using Phos-tag gels and phosphorylation site-specific antibodies in transfected cells and in platelets. Cyclic nucleotide-induced detachment of 14-3-3 from RGS18 coincides initially with double phosphorylation of S216 and S218. This is followed by dephosphorylation of S49 and S218. Dephosphorylation of S49 and S218 might be mediated by protein phosphatase 1 (PP1) which is linked to RGS18 by the regulatory subunit PPP1R9B (spinophilin). We conclude that PKA and PKG induced S216 phosphorylation triggers the dephosphorylation of the 14-3-3 binding sites of RGS18 in platelets. 相似文献
85.
Abstract The Dutch have a long tradition of hospitality towards ethnic immigrants. In the nineties, however, quite dramatic changes have taken place among the Dutch. The central question addressed in this contribution is: to what extent do specific categories within the electorate favour ethnocentric policies? This question is answered by deducing hypotheses that are tested using recent data polled within the framework of the Dutch National Election Studies. Our crucial conclusion is that a rather widespread support for ethnocentric policies is present in contemporary Dutch society, especially among manual labourers, self‐employed and lowly educated people, but also among young cohorts and among modal income categories. 相似文献
86.
Following radiation therapy (RT), tumor morphology may remain unchanged for days and sometimes weeks, rendering anatomical imaging methods inadequate for early detection of therapeutic response. Changes in the hyperpolarized [1-13C]lactate signals observed in vivo following injection of pre-polarized [1-13C]pyruvate has recently been shown to be a marker for tumor progression or early treatment response. In this study, the feasibility of using 13C metabolic imaging with [1-13C]pyruvate to detect early radiation treatment response in a breast cancer xenograft model was demonstrated in vivo and in vitro. Significant decreases in hyperpolarized [1-13C]lactate relative to [1-13C]pyruvate were observed in MDA-MB-231 tumors 96 hrs following a single dose of ionizing radiation. Histopathologic data from the treated tumors showed higher cellular apoptosis and senescence; and changes in the expression of membrane monocarboxylate transporters and lactate dehydrogenase B were also observed. Hyperpolarized 13C metabolic imaging may be a promising new tool to develop novel and adaptive therapeutic regimens for patients undergoing RT. 相似文献
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M. Albert Menzies 《CMAJ》1965,93(14):743-747
Various forms of collaboration between the disciplines of public health and psychiatry are briefly reviewed and the 25-year-old mental health program of the Vancouver Health Department is described. The public health nurse has prime responsibility in all children with emotional disorders. She is supported by a psychiatric team which provides active treatment and educational and consultative help for the nurse and the school. During the year 1963, six social workers had 2357 contacts with nurses and school personnel but only 1049 treatment interviews. Of 401 children referred to the psychiatric team, 138 received active clinic treatment, 141 remained under supervision by the public health nurse, and 122 were referred elsewhere. In addition, 1330 children were identified as “mental hygiene cases” in the caseload of the 170 public health nurses in the community. By close co-ordination, the public health nurse and the psychiatric team can enhance each other''s contributions to community mental health. 相似文献
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90.