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91.
Nora N. Hanson Gordon W. Smith Stuart J. Middlemas Christopher D. Todd 《Journal of fish biology》2019,94(1):183-186
Using tagged and recaptured Atlantic salmon Salmo salar (n = 106) the present analysis shows that the most commonly applied linear back-calculation method for estimating past length, the Dahl-Lea method, resulted in overestimation of the length of large smolts and underestimation of small smolts. A correction equation (y = 0.53x + 6.23) for estimating true smolt length (y) from lengths back-calculated from adult scale measures (x) to account for these systematic discrepancies is proposed. 相似文献
92.
E. Günther K. Skiebe W. Mante Hagemann P. Metzner K. Gröber Ramshorn Nover F. Scholz Hanson Keppler 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1964,34(6-7):292-296
Ohne Zusammenfassung 相似文献
93.
Isoprene is emitted from the leaves of many plants in a light‐dependent and temperature‐sensitive manner. Plants lose a large fraction of photo‐assimilated carbon as isoprene but may benefit from improved recovery of photosynthesis following high‐temperature episodes. The capacity for isoprene emission of plants in natural conditions (assessed as the rate of isoprene emission under standard conditions) varies with weather. Temperature‐controlled greenhouses were used to study the role of temperature and light in influencing the capacity of oak leaves for isoprene synthesis. A comparison was made between the capacity for isoprene emission and the accumulation of other compounds suggested to increase thermotolerance of photosynthesis under two growth temperatures and two growth light intensities. It was found that the capacity for isoprene emission was increased by high temperature or high light. Xanthophyll cycle intermediates increased in high light, but not in high temperature, and the chloroplast small heat‐shock protein was not expressed in any of the growth conditions. Thus, of the three thermotolerance‐enhancing compounds studied, isoprene was the only one induced by the temperature used in this study. 相似文献
94.
Phosphate absorption rates and adenosine 5'-triphosphate concentrations in corn root tissue 下载免费PDF全文
The correlations between ATP concentration in corn (Zea mays) root tissue and the rate of phosphate absorption by the tissue have been examined. Experimental variation was secured with 2,4-dinitrophenol, oligomycin, mersalyl, l-ethionine, 2-deoxyglucose, N2 gassing and inhibition of protein synthesis. It is concluded that ATP could be the energy source for potassium phosphate absorption, but only if the transport mechanism possesses certain properties: oligomycin-sensitivity; creation of a proton gradient susceptible to collapse by uncouplers; phosphate transport via a mersalyl-sensitive Pi−-OH− transporter; good activity at energy charge as low as 0.4; short enzymatic half-life for the ATPase or phosphate transporter; a linked mechanism for K+-H+ exchange transport, possibly electrogenic. 相似文献
95.
Richard J. Norby Joanne Childs Paul J. Hanson Jeffrey M. Warren 《Ecology and evolution》2019,9(22):12571-12585
Sphagnum mosses are keystone components of peatland ecosystems. They facilitate the accumulation of carbon in peat deposits, but climate change is predicted to expose peatland ecosystem to sustained and unprecedented warming leading to a significant release of carbon to the atmosphere. Sphagnum responses to climate change, and their interaction with other components of the ecosystem, will determine the future trajectory of carbon fluxes in peatlands. We measured the growth and productivity of Sphagnum in an ombrotrophic bog in northern Minnesota, where ten 12.8‐m‐diameter plots were exposed to a range of whole‐ecosystem (air and soil) warming treatments (+0 to +9°C) in ambient or elevated (+500 ppm) CO2. The experiment is unique in its spatial and temporal scale, a focus on response surface analysis encompassing the range of elevated temperature predicted to occur this century, and consideration of an effect of co‐occurring CO2 altering the temperature response surface. In the second year of warming, dry matter increment of Sphagnum increased with modest warming to a maximum at 5°C above ambient and decreased with additional warming. Sphagnum cover declined from close to 100% of the ground area to <50% in the warmest enclosures. After three years of warming, annual Sphagnum productivity declined linearly with increasing temperature (13–29 g C/m2 per °C warming) due to widespread desiccation and loss of Sphagnum. Productivity was less in elevated CO2 enclosures, which we attribute to increased shading by shrubs. Sphagnum desiccation and growth responses were associated with the effects of warming on hydrology. The rapid decline of the Sphagnum community with sustained warming, which appears to be irreversible, can be expected to have many follow‐on consequences to the structure and function of this and similar ecosystems, with significant feedbacks to the global carbon cycle and climate change. 相似文献
96.
97.
Stephanie A. Norman Jessie Huggins Tim E. Carpenter James T. Case Dyanna M. Lambourn Jim Rice John Calambokidis Joseph K. Gaydos M. Bradley Hanson Deborah A. Duffield Sandra Dubpernell Susan Berta Matt Klope 《Marine Mammal Science》2012,28(3):E251-E266
In 2006–2007, an unusually high number of harbor porpoises (Phocoena phocoena) stranded along the Washington and Oregon coastlines. Spatiotemporal analyses were used to examine their ability to detect clusters of porpoise strandings during an unusual mortality event (UME) in the Pacific Northwest using stranding location data. Strandings were evaluated as two separate populations, outer coast and inland waters. The presence of global clustering was evaluated using the Knox spatiotemporal test, and the presence of local clusters was investigated using a spatiotemporal scan statistic (space–time permutation). There was evidence of global clustering, but no local clustering, supporting the hypothesis that strandings were due to more varied etiologies instead of localized causes. Further analyses at subregional levels, and concurrently assessing environmental factors, might reveal additional geographic distribution patterns. This article describes the spatial analytical tools applied in this study and how they can help elucidate the spatiotemporal epidemiology of other UMEs and assist in determining their causes. More than one spatial analytical technique should be used if the study objective is to detect and describe clustering in time and space and to generate hypotheses regarding causation of marine mammal disease and stranding events. 相似文献
98.
Wetland mitigation and compensation: Canadian experience 总被引:3,自引:0,他引:3
Since Canada’s accession to the Ramsar Convention on Wetlands in 1981, the nation’s commitment to wetland conservation and
management has increased significantly. This includes the adoption of one of the World’s first national wetland conservation
policies by the Government of Canada, and the adoption of complementary policy and legislative initiatives by most of the
13 provincial and territorial jurisdictions. Numerous habitat ‘no net loss’ and environmental assessment policies, regulations
and guidelines for incorporating mitigation processes into development decisions affecting wetland resources are used throughout
Canada. The governments of Canada and six provinces have so far adopted wetland mitigation measures. These are in addition
to comprehensive wetland fish and wildlife habitat initiatives, such as the species and habitat joint ventures delivered in
Canada through the North American Waterfowl Management Plan by all jurisdictions and numerous non-government partners. This
paper examines the current policies, regulations and programs, as well as past implementation experience with wetland mitigation
and compensation in Canada. 相似文献
99.
Conrad E. Chan Bryan Z. Zhao Amaury Cazenave-Gassiot Shyue-Wei Pang Anne K. Bendt Markus R. Wenk Paul A. MacAry Brendon J. Hanson 《Journal of lipid research》2013,54(10):2924-2932
Tuberculosis is a major cause of mortality and morbidity due to infectious disease. However, current clinical diagnostic methodologies such as PCR, sputum culture, or smear microscopy are not ideal. Antibody-based assays are a suitable alternative but require specific antibodies against a suitable biomarker. Mycolic acid, which has been found in patient sputum samples and comprises a large portion of the mycobacterial cell wall, is an ideal target. However, generating anti-lipid antibodies using traditional hybridoma methodologies is challenging and has limited the exploitation of this lipid as a diagnostic marker. We describe here the isolation and characterization of four anti-mycolic acid antibodies from a nonimmune antibody phage display library that can detect mycolic acids down to a limit of 4.5ng. All antibodies were specific for the methoxy subclass of mycolic acid with weak binding for α mycolic acid and did not show any binding to closely related lipids or other Mycobacterium tuberculosis (Mtb) derived lipids. We also determined the clinical utility of these antibodies based on their limit of detection for mycobacteria colony forming units (CFU). In combination with an optimized alkaline hydrolysis method for rapid lipid extraction, these antibodies can detect 105 CFU of Mycobacterium bovis BCG, a close relative of Mtb and therefore represent a novel approach for the development of diagnostic assays for lipid biomarkers. 相似文献
100.
Emily HM Wong David K Smith Raul Rabadan Malik Peiris Leo LM Poon 《BMC evolutionary biology》2010,10(1):253