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91.
Szucs Regina P.; Frankel Paul S.; McMahon Lance R; Cunningham Kathryn A. 《Canadian Metallurgical Quarterly》2005,119(5):1173
Serotonin 5-HT2A receptor antagonists have been shown to attenuate the locomotor stimulant effects of cocaine in rats. The present study used the expression of c-Fos protein as a marker to identify brain areas through which 5-HT2A receptors may modulate cocaine-induced behaviors. Significant correlations were observed between cocaine-induced hyperactivity and c-Fos expression in the nucleus accumbens core (NAcC), caudate-putamen (CPu), and subthalamic nucleus. In a separate experiment, a low, behaviorally relevant dose of cocaine was found to increase c-Fos immunoreactivity in the medial CPu, NAcC, and nucleus accumbens shell (NAcSh). The selective 5-HT2A receptor antagonist M100907 significantly attenuated cocaine-induced c-Fos expression in the medial CPu and in the NAcSh. These data suggest that 5-HT2A receptors in the NAcSh and CPu or in afferents to these regions may contribute to genomic responses to cocaine in the brain as well as to cocaine-induced locomotor activity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
92.
The purpose of this study was to test competing theories regarding the relationship between true halo (actual dimensional correlations) and halo rater error (effects of raters' general impressions on specific ratee qualities) at both the individual and group level of analysis. Consistent with the prevailing general impression model of halo rater error, results at both the individual and group level analyses indicated a null (vs. positive or negative) true halo-halo rater error relationship. Results support the ideas that (a) the influence of raters' general impressions is homogeneous across rating dimensions despite wide variability in levels of true halo; (b) in assigning ratings, raters rely both on recalled observations of actual ratee behaviors and on general impressions of ratees in assigning dimensional ratings; and (c) these 2 processes occur independently of one another. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
Garcia Hector A.; Kelley Lance P.; Rentz Timothy O.; Lee Shuko 《Canadian Metallurgical Quarterly》2011,8(1):1
Cognitive–behavioral therapies (CBTs) can be effective treatments for posttraumatic stress disorder (PTSD) but their effectiveness is limited by high rates of premature dropout. Few studies have compared pretreatment characteristics of treatment completers and dropouts, and only one has examined these factors in Operations Iraqi Freedom and Enduring Freedom (OIF/OEF) Veterans. This study analyzed archival clinical data from 117 OEF/OIF Veterans evaluated and treated through a Veterans Affairs PTSD clinic. High numbers dropped out of treatment (68%). Treatment dropouts (n = 79) and completers (n = 38) differed significantly on Minnesota Multiphasic Personality Inventory-2 (MMPI-2) scales, PTSD symptom severity, and age. Regression analyses identified one MMPI-2 scale, TRT (negative treatment indicators), and age as unique but modest predictors of dropout. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
94.
One of the methods of evaluating the reliability of alternative forms of assessment instruments is to evaluate the relation of the 2 forms to other measures in a factor analysis. Using this method, the authors investigated the reliability of alternate forms of Trail Making Tests A and B, called Trails C and D. Neuropsychological screening test data were collected from the files of 144 clients referred to a university hospital for neuropsychological evaluations. The tests included Trail Making Tests A, B, C, and D; the Digit Symbol subtest of the Wechsler Adult Intelligence Scale—Revised; and the Stroop Color-Word test. Analyses provided tentative support for the equivalency of the alternative forms of the Trail Making Test. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
Ehud Greenspan Ser Gi Hong Ki Bog Lee Lanfranco Monti Tsuyoshi Okawa Arnaud Susplugas Massimiliano Fratoni Lance Kim Sara Mattafirri Robert Petroski 《Progress in Nuclear Energy》2008,50(2-6):129-139
A number of approaches were explored for improving characteristics of the encapsulated nuclear heat source (ENHS) reactor and its fuel cycle, including: increasing the ENHS module power, power density and the specific power, making the core design insensitive to the actinides composition variation with number of fuel recycling and reducing the positive void coefficient of reactivity. Design innovations examined for power increase include intermediate heat exchanger (IHX) design optimization, riser diameter optimization, introducing a flow partition inside the riser, increasing the cooling time of the LWR discharged TRU, increasing the minor actinides' concentration in the loaded fuel and split-enrichment for power flattening. Another design innovation described utilizes a unique synergism between the use of MA and the design of reduced power ENHS cores.
Also described is a radically different ENHS reactor concept that has a solid core from which heat pipes transport the fission power to a coolant circulating around the reflector. Promising features of this design concept include enhanced decay heat removal capability; no positive void reactivity coefficient; no direct contact between the fuel clad and the coolant; a core that is more robust for transportation; higher coolant temperature potentially offering higher energy conversion efficiency and hydrogen production capability. 相似文献
96.
John M. E. Storey C. Scott Sluder Michael J. Lance Daniel J. Styles Steven J. Simko 《传热工程》2013,34(8-9):655-664
This article reports on the results of experimental efforts aimed at improving the understanding of the mechanisms and conditions at play in the fouling of exhaust gas recirculation coolers. An experimental apparatus was constructed to utilize simplified surrogate heat exchanger tubes in lieu of full-size heat exchangers. The use of these surrogate tubes allowed removal of the tubes after exposure to engine exhaust for study of the deposit layer and its properties. The exhaust used for fouling the surrogate tubes was produced using a modern medium-duty diesel engine fueled with both ultra-low-sulfur diesel and biodiesel blends. At long exposure times, no significant difference in the fouling rate was observed between fuel types and hydrocarbons levels. Surface coatings for the tubes were also evaluated to determine their impact on deposit growth. No surface treatment or coating produced a reduction in the fouling rate or any evidence of deposit removal. In addition, microstructural analysis of the fouling layers was performed using optical and electron microscopy in order to better understand the deposition mechanism. The experimental results are consistent with thermophoretic deposition for deposit formation, and van der Waals attraction between the deposit surface and exhaust-borne particulate. 相似文献
97.
1. n-Butyrate, a short chain fatty acid produced by colonic fermentation, induces differentiation in human neoplastic cell lines, and reduces expression in vitro of a sialyltransferase that glycosylates N-linked glycoproteins in hepatoblastoma cells. Gangliosides are amphipathic, sialylated glycosphingolipids that undergo profound changes in many transformed cells and may protect neoplastic cells from host immune surveillance. Colonic mucosal cells are exposed to luminal short-chain fatty acid concentrations of up to 80 mmol/l, and there is some evidence that short-chain fatty acids may alter ganglioside expression in colon cancer cells. 2. Because of the importance of gangliosides in cancer pathogenesis, we investigated the effects of n-butyrate on ganglioside expression of colonic (human and murine) and non-colonic cancer cells. 3. Three separate colon cancer cell lines (LS174T, T84 and MCA-38), when butyrate treated, demonstrated striking amplification of specific individual gangliosides. However, the total lipid-bound sialic acid content of gangliosides of butyrate-treated LS174T cells diminished. In contrast to earlier reports, n-butyrate did not mediate expression of all gangliosides and specifically did not mediate expression of GM3. This effect persisted even after removal of butyrate. 4. In contrast, exposure of extracolonic cells to butyrate, including cervical cancer (HeLa) and laryngeal cancer (HEp-2) cell lines in this study and hepatoblastoma cells (Hep G2) in our previous work, caused no detectable changes in ganglioside expression. 5. In conclusion, our results indicate a relative tissue specificity of butyrate-mediated alterations in ganglioside expression that is not universal but is limited to specific gangliosides. 相似文献
98.
J. D. Warthen C.-J. Lee E. B. Jang D. R. Lance D. O. McInnis 《Journal of chemical ecology》1997,23(7):1891-1900
Twenty-eight volatile compounds from freshly crushed, ripe, dark red coffee fruit, Coffea arabica, were identified by dynamic headspace analysis techniques. Identifications were made on the basis of a comparison of Kovats indices and GC-MS spectra for unknowns and authentic samples. Of the compounds identified, 10 were alcohols, nine were aldehydes, five were ketones, and four were monoterpenes. The five most abundant volatiles in decreasing order were hexanal (21%), 2-(E)-hexenal (11%), 3-methyl-1-butanol (9.0%), 3-methyl-1-butanal (8.5%), and 1-hexanol (8.4%). The five least abundant volatiles of the 28 identified, in increasing order, were decanal (0.19%), methyl hexanoate (0.33%), pulegone (0.44%), α-isomenthone (0.45%), and 2-nonanone (0.55%). In preliminary tests, many of the identified volatiles attracted more female Mediterranean fruit flies than the control. 相似文献
99.
Thomas P. Sullivan Lance O. Nordstrom Druscilla S. Sullivan 《Journal of chemical ecology》1985,11(7):903-919
The effectiveness of predator odors (fecal, urine, and anal scent gland) in suppressing feeding damage by snowshoe hares was investigated in pen bioassays at the University of British Columbia Research Forest, Maple Ridge, British Columbia, Canada. A total of 28 bioassay trials tested the effects of these odors on hare consumption of willow browse and coniferous seedlings. Lynx and bobcat feces, weasel anal gland secretion, and lynx, bobcat, wolf, coyote, fox, and wolverine urines resulted in the most effective suppression of hare feeding damage. Novel odors of domestic dog urine and 2-methylbutyric acid did not reduce feeding. A field bioassay with lodgepole pine seedlings and weasel scent provided significant results comparable to the pen bioassays. The short-term (up to seven days) effectiveness of these treatments was more likely due to evaporative loss of the active repellent components of a given odor than habituation of hares to the stimulus. Predator odors as repellents have a biological basis compared with the anthropomorphic origins of commercial repellents. When encapsulated in weather-proof controlled-release devices, these odors could provide long-term protection for forestry plantations and agricultural crops which experience hare/rabbit feeding damage. 相似文献
100.
The stresses and deformations in a thin ring-disk shrink fit assembly have been analyzed. The interface pressure for the presumed plane stress state has been found as a function of the interference of the fit. Interferences large enough to induce plastic deformations in the ring are accounted for. The ring material was assumed to be a linear work-hardening material that obeys Tresca's yield condition. For design purposes a graph of interface pressure and hence the hydrostatic stress state in the disk, as a function of interference, is provided. 相似文献