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61.
Reports evidence for the criterion validity of the Alcohol Use Inventory (AUI) by showing that the instrument accurately identifies expected differences in a specific condition (alcohol severity) in 2 contrasting groups of alcohol abusers. 200 male veterans admitted to an inpatient alcohol program were categorized as to whether or not they had a father who abused alcohol. Ss with a father who abused alcohol scored significantly higher on AUI scales measuring alcohol abuse severity and alcohol-related problems than veterans with no such history. Differences in patterns of and benefits from alcohol use were not found. Results provide further evidence of the validity of the AUI. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
62.
In some cases, the search for a conjunction target proceeds through the smaller group of elements in a display, whereas in others, search is limited to those elements that share a particular feature with the target. In 6 experiments, participants searched for a conjunction target among displays consisting of various proportions of 2 distractor types. Smaller-group search was more prevalent than target-feature search with denser displays and with features that were highly discriminable. Explicit instructions to limit search to a specific feature affected performance only when the discriminability of the guiding feature was much greater than the other target feature. Together, these experiments show that bottom-up factors have more influence in guiding conjunction searches than previously thought. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
63.
Surface pressure and wind load characteristics on prisms immersed in a simulated transient gust front flow field 总被引:1,自引:0,他引:1
Kyle Butler Shuyang Cao Ahsan Kareem Yukio Tamura Shigehira Ozono 《Journal of Wind Engineering & Industrial Aerodynamics》2010,98(6-7):299-316
Thunderstorm generated gust fronts are responsible for various degrees of structural damage in many areas of the world. However, the resulting impact of gust front winds is not fully understood to such a level that their flow kinematics, dynamics and impact on structures can be quantified with some certainty. Gust front winds are transient in nature and have a flow profile which differs significantly from a typical boundary layer flow field. This study focuses on investigating the effects of this flow profile and its transient nature on the aerodynamics of bluff, prismatic bodies. A gust front type flow field is generated using a multiple fan wind tunnel and the resulting surface pressures are captured on a suite of prismatic models, which vary in size in relationship to the oncoming wind profile. The temporal variations in surface pressures are analyzed using traditional time, frequency and time-frequency domain schemes. Results indicate the changing nature of the surface pressure field in time, highlighting both qualitative and quantitative differences between local and area-averaged pressures under a host of flow profiles. 相似文献
64.
Natalie M. Johnson Li Xu Alicia Marroquin-Cardona Melanie Rodriguez Kyle Cunningham Fernando Guerra Jonathan H. Williams Timothy D. Phillips 《The Science of the total environment》2010,408(23):6027-6031
The incidence of hepatocellular carcinoma (HCC) is significantly elevated in a Hispanic community in Bexar County, Texas. Chronic exposure to dietary aflatoxins (AFs) is a major risk factor for HCC; increased risk has been linked to polycyclic aromatic hydrocarbon (PAH) co-exposure and hepatitis virus infection. The aims of this study were to assess AF and PAH exposures, investigate dietary factors that may contribute to increased AF exposure, and determine the prevalence of hepatitis virus infection in Bexar Co. Blood and urine samples were collected from 184 volunteers for biomarker analyses and hepatitis screening. Serum AFB1-lysine adduct, urinary AFM1 and 1-hydroxypyrene (1-OHP) levels were measured using high-performance liquid chromatography. The average AFB1-lysine adduct level detected in 20.6% of serums was 3.84 ± 3.11 pg/mg albumin (range 1.01-16.57 pg/mg). AFM1 was detected in 11.7% of urines, averaging 223.85 ± 250.56 pg/mg creatinine (range 1.89-935.49 pg/mg). AFM1 detection was associated with increased consumption of corn tortillas (p = 0.009), nuts (p = 0.033) and rice (p = 0.037). A significant difference was observed between mean 1-OHP values of non-smokers (0.07 ± 0.13) and smokers (0.80 ± 0.68) μmol/mol creatinine (p < 0.01). A high hepatitis C virus positivity rate (7.1%) was observed. Findings suggest that the incidence and level of AF and PAH exposure were less than those observed in a high-risk population; however, participants consuming higher amounts of foods prone to AF contamination may be more vulnerable to exposure and interactions with other environmental/biological factors (i.e., HCV). 相似文献
65.
Artificial structures have been used to potentially increase fish production by providing cover, feeding and spawning areas. In some rivers, the United States Army Corps of Engineers has constructed dikes to provide additional habitat for river fishes and to mitigate for navigation impacts to young fishes. This study was designed to test whether such structures function as viable habitats as evidenced by increased abundances relative to reference areas lacking artificial dike structures. Dikes and reference sites in the Kanawha River, West Virginia were sampled 21 times between July 2002 and October 2003. We found a difference in taxonomic composition among fish using dikes relative to reference areas. Artificial dike structure use was most important among Centrarchidae species, especially juveniles, including black bass and several species of Lepomis. Further, distribution of fish between areas with and without dikes appears most affected by water temperature in 2002 and by short‐term river flow in 2003. These patterns suggest these artificial structures are viable mitigation measures that target and benefit fish of economic interest. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
66.
The importance of graph search algorithm choice to the directed relation graph with error propagation (DRGEP) method is studied by comparing basic and modified depth-first search, basic and R-value-based breadth-first search (RBFS), and Dijkstra’s algorithm. By using each algorithm with DRGEP to produce skeletal mechanisms from a detailed mechanism for n-heptane with randomly-shuffled species order, it is demonstrated that only Dijkstra’s algorithm and RBFS produce results independent of species order. In addition, each algorithm is used with DRGEP to generate skeletal mechanisms for n-heptane covering a comprehensive range of autoignition conditions for pressure, temperature, and equivalence ratio. Dijkstra’s algorithm combined with a coefficient scaling approach is demonstrated to produce the most compact skeletal mechanism with a similar performance compared to larger skeletal mechanisms resulting from the other algorithms. The computational efficiency of each algorithm is also compared by applying the DRGEP method with each search algorithm on the large detailed mechanism for n-alkanes covering n-octane to n-hexadecane with 2115 species and 8157 reactions. Dijkstra’s algorithm implemented with a binary heap priority queue is demonstrated as the most efficient method, with a CPU cost two orders of magnitude less than the other search algorithms. 相似文献
67.
Madon Stephanie; Guyll Max; Buller Ashley A.; Scherr Kyle C.; Willard Jennifer; Spoth Richard 《Canadian Metallurgical Quarterly》2008,95(2):369
This research examined whether self-fulfilling prophecy effects are mediated by self-verification, informational conformity, and modeling processes. The authors examined these mediational processes across multiple time frames with longitudinal data obtained from two samples of mother-child dyads (N? = 486; N? = 287), with children's alcohol use as the outcome variable. The results provided consistent support for the mediational process of self-verification. In both samples and across several years of adolescence, there was a significant indirect effect of mothers' beliefs on children's alcohol use through children's self-assessed likelihood of drinking alcohol in the future. Comparatively less support was found for informational conformity and modeling processes as mediators of mothers' self-fulfilling effects. The potential for self-fulfilling prophecies to produce long-lasting changes in targets' behavior via self-verification processes are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
68.
69.
The enhancement of the 1 day strength of cementitious systems by a combination of calcium chloride (CaCl2) and diethanol-isopropanolamine (DEIPA) was studied, particularly in blended cement systems. A combination of quantitative X-ray diffraction with Rietveld refinement (QXRD), scanning electron microscopy (SEM)/backscattered electron image analysis, thermogravimetric analysis (TGA), and isothermal calorimetry were used to investigate the mechanism of strength enhancement by the additives. The additives were found to increase the early age mortar strength by enhancing the cement hydration, with the DEIPA enhancing primarily the aluminate hydration. DEIPA also affected the morphology of portlandite which was formed as thin plates. In parallel, the calcium-to-silica ratio of the C-S-H was found to increase with the use of DEIPA, possibly because of the inclusion of microcrystalline portlandite. After 48 h DEIPA was found to directly enhance the rate of reaction of granulated blast-furnace slag and fly ash. 相似文献
70.
Research productivity affects the careers of academic psychologists. Unfortunately, there is a surprising lack of consensus
on productivity’s meaning, measurement, and how to compare the productivity of one academic psychologist to another. In the
present study, we review academic productivity research within psychology, and using a sample of 673 psychologists, compute
six indexes of productivity. Most productivity metrics (publication count, citation count, or some combination of the two)
were substantially interrelated and one (Integrated Research Productivity Index) was independent from years in the field.
Female psychologists were equally as productive as male psychologists after accounting for years in the field, and pre-tenure
psychologists showed steeper change-over-time productivity slopes than post-tenure psychologists. Based on these findings,
we provide recommendations for the use and measurement of academic research productivity. 相似文献