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111.
Dale C. Honeyfield Amber K. Peters Michael L. Jones 《Journal of Great Lakes research》2008,34(4):581-589
Nutritional status of Lake Michigan Chinook salmon (Oncorhynchus tshawytscha) is inadequately documented. An investigation was conducted to determine muscle and liver thiamine content and whole body fatty acid composition in small, medium and large Chinook salmon. Muscle and liver thiamine concentrations were highest in small salmon, and tended to decrease with increasing fish size. Muscle thiamine was higher in fall than spring in large salmon. The high percentage of Chinook salmon (24–32% in fall and 58–71% in spring) with muscle thiamine concentration below 500 pmol/g, which has been associated with loss of equilibrium and death in other Great Lake salmonines, suggest that Chinook appear to rely less on thiamine than other Great Lakes species for which such low concentrations would be associated with thiamine deficiency (Brown et al. 2005b). A positive correlation was observed between liver total thiamine and percent liver lipids (r = 0.53, P < 0.0001, n = 119). In medium and large salmon, liver lipids were observed to be low in fish with less than 4,000 pmol/g liver total thiamine. In individuals with greater than 4,000 pmol/g liver thiamine, liver lipid increased with thiamine concentration. Individual fatty acids declined between fall and spring. Essential omega-3 fatty acids appear to be conserved as lipid content declined. Arachidonic acid (C20:4n6), an essential omega-6 fatty acid was not different between fall and spring, although the sum of omega-6 (Sw6) fatty acids declined over winter. Elevated concentrations of saturated fatty acids (sum) were observed in whole body tissue lipid. In summary, thiamine, a dietary essential vitamin, and individual fatty acids were found to vary in Lake Michigan Chinook salmon by fish size and season of the year. 相似文献
112.
113.
This article examines the perceptual consequences of activating illness concern as a function of hypochondriacal tendencies. In 2 independent samples, hypochondriacal tendencies were associated with slower reaction times on a modified emotional Stroop task when the stimulus words were illness related, but only when illness concern was activated. Moreover, these findings emerged when hypochondriacal tendencies were defined as a sensitivity to bodily sensations. When defined as illness preoccupation and fear, hypochondriacal tendencies were associated with a generalized pattern of perseveration to all stimuli when health concern was activated. Finally, the results persisted even after statistically controlling for state anxiety. Findings are discussed within the context of an activation hypothesis and highlight the importance of the operational definition and assessment of hypochondriacal tendencies when examining perceptual biases. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
114.
This paper reports the main findings of a questionnaire survey on the use of failure mode and effects analysis (FMEA) in the United Kingdom motor industry. Survey data were obtained from 78 organizations. Among the main findings are: the majority of suppliers only started to use FMEA because it was a contractual requirement of their customer; however, a number of them are now seeking to make more use of the technique to facilitate their process of quality improvement; FMEA is treated by the majority of organizations as a team activity; engineers still view FMEA as a hard slog; more use should be made of computerized aids to reduce the effort in preparing and updating the FMEA; and the main difficulties encountered in the use of FMEA are related to time constraints, poor organizational understanding of the importance of FMEA, inadequate training and lack of management commitment. It is also pointed out that organizations are not satisfied with the current training courses on FMEA. 相似文献
115.
Howard A. Blackstead John D. Dow Dale R. Harshman 《Journal of Superconductivity and Novel Magnetism》2000,13(6):981-983
Sr2YRuO6 doped on its Ru site by Cu superconducts at the below ~45 K, although its Ru and Cu are magnetically ordered at ~23 K and ~86 K, respectively. The SrO layers superconduct. Ba2GdRuO6, when doped with Cu, does not superconduct, because L = 0 Gd is not crystal-field split, and so induces Cooper pair-breaking. 相似文献
116.
There is increasing evidence that the major source of drawing errors lies in the initial perception of the to-be-drawn object. In four experiments, the authors explore the relation between an artist's susceptibility to perceptual transformations, as measured by a simple shape constancy task, and drawing accuracy. The data reveal a robust negative relation between errors on the shape constancy task and drawing accuracy in general, and specifically the accuracy of the rendering of spatial relations. The data further suggest that the perceptual processes that lead to errors on the shape constancy task occur during the initial encoding of the stimuli. The authors conclude that the shape constancy task likely measures one's ability to overcome constructive perception processes that transform the retinal image into a final percept, and that this ability is necessary for the accurate rendering of objects. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
117.
Cannon Dale S.; Bell William E.; Fowler D. Robert; Penk Walter E.; Finkelstein Allan S. 《Canadian Metallurgical Quarterly》1990,2(1):51
Inpatients in Veterans Administration substance-abuse treatment programs voluntarily took the Minnesota Multiphasic Personality Inventory (MMPI) as part of a routine clinical evaluation. The alcohol-dependence-only group (n?=?207) were older (M?=?49.6 years) and had a higher percentage of White Ss (72.9%) than did either the drug-dependence group (n?=?49, M?=?32.9 years, Whites?=?53.1%) or a mixed alcohol- and drug-dependence group (n?=?160, M?=?35.0 years, Whites?=?60.0%). Previously reported differences between alcoholics and drug abusers in depression and psychopathy were obtained when age and race were not used as covariates, but no differences were found when the effects of age and race were statistically controlled. Mixed alcohol and drug abusers had somewhat more pathological MMPI scores than did alcoholics, even when effects due to age and race were partialed out. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
118.
W. Chad Vaughan Dale H. Easley Dawn L. Lavoie 《Canadian Metallurgical Quarterly》2002,128(11):1002-1007
Effective medium theory (EMT) was employed to estimate permeability of fine-grained estuarine sediments. X-radiographs were taken of sediment cores collected in the field and from laboratory aquaria, designed to mimic the benthic environment of an estuary. Image analysis of two-dimensional X rays provided values of pore parameters required by the EMT model, which include pore body and throat radii, pore throat length, porosity, and the interconnectivity of pores. Values of these parameters were used to quantitatively calculate permeability based upon Darcy’s law. The EMT model with an arithmetic mean for averaging pore parameters predicted permeability 1 order of magnitude higher than measured values. The harmonic mean for averaging pore parameters in the EMT model provided estimates of permeability similar to measured values. 相似文献
119.
Determination of platinum in blood by adsorptive voltammetry 总被引:2,自引:0,他引:2
O Nygren G T Vaughan T M Florence G M Morrison I M Warner L S Dale 《Analytical chemistry》1990,62(15):1637-1640
This work describes a sensitive method for the determination of platinum in blood, which can be used for determining the natural levels of platinum in human blood, for monitoring patients treated with platinum cytotoxic drugs, and for monitoring occupational exposure to these drugs and other platinum compounds. The method involves dry ashing of blood samples in a muffle furnace and determination of platinum by adsorptive voltammetric (AV) measurement of the catalytic reduction of protons by the platinum-formazone complex. The detection limit for a 100-microL sample of blood is 0.017 micrograms/L, with a recovery of 94% and a relative standard deviation of 7% at a platinum level of 1 microgram/L. By using this method, the natural levels of platinum in human blood were found to be in the range 0.1-2.8 micrograms/L (median = 0.6 micrograms/L). These results were verified by inductively coupled plasma mass spectrometry (ICP-MS) with blood prepared by wet ashing and using gold as an internal standard. 相似文献
120.
Millions of people in developing countries obtain water from commercial vendors who deliver it to their homes, yet this phenomenon has received little attention from professionals in the water resources field. This paper describes a water vending system which is in operation in Ukunda, Kenya, a town of about 5000 people south of Mombasa. In this community 45% for water consumed by households is obtained from water vendors who deliver water in carts directly to people's homes. The prices vendors charge for water are high, but vendors are not making exorbitant profits; hauling water manually is simply expensive. People in Ukunda spend about 9% of their income on vended water, which suggests that there are situations in which households are willing and able to pay substantial amounts of money for water even when traditional sources are readily available. 相似文献