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131.
Two experiments with 72 undergraduates investigated attraction to a stranger, which has been previously shown to depend on the social context within which that directed action is acquired. In both experiments, a confederate stranger agreed with the S 100% of the time. Attraction to the stranger, however, was blocked if the stranger agreed with the S while in the presence of someone the S already found attractive. Based on these findings, the present authors employed N. E. Miller's (1959) "extension of liberalized stimulus–response theory" in developing a reinforcement-context theory to predict acquisition and blocking effects in attraction. Additional novel predictions addressing contextual phenomena are generated from the theory. (45 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
132.
The constructs of horizontal (H) and vertical (V) individualism (I) and collectivism (C) were theoretically defined and empirically supported. Study 1 confirmed, via factor analysis, that the 4 constructs, HI, V1, HC, and VC, which were previously found in the United States, which has an individualist culture, also were found in Korea which has a collectivist culture. Study 2 investigated multimethod-multitrait matrices measuring the constructs and generally supported their convergent and divergent validity. Study 3 showed how these 4 constructs relate to previously identified components by H. C. Triandis and colleagues. Study 4 showed the relationships of the measurement of the 4 constructs to some of the measures used by other researchers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
133.
It has recently been noted that hemispherical structures have useful reflection characteristics. We describe a new application that makes use of these characteristics by controlling the reflectance of a surface composed of an array of hemispherical liquid droplets. In this system the reflectance state is spatially controlled through the use of electrowetting to alter the shape of an array of droplets. This may have an application in the field of electronic image displays.  相似文献   
134.
One of the main limitations when accessing the web is the lack of explicit structure, whose presence may help in understanding data semantics. Schema for web data can be constructed at different levels, structuring a single pages or a whole site or group of sites. Here we present an approach to give a logical schema to a web-site, first defining a model for a single page, where its contents is divided into logical sections, i.e. parts of a page each collecting related information. Then, we introduce a site model in which both physical and logical links among different page sections are represented: physical are existing hyperlinks, while logical links are links between sections containing semantically related information. We show how such links can be found and classified according to their relevance, also showing how schema is used in a structure-aware browser to improve both browsing and searching.  相似文献   
135.
The proteins streptavidin and avidin were electrochemically detected in solution by adsorptive transfer stripping square wave voltammetry (AdTS SWV) at a carbon paste electrode (CPE). AdTS SWV was used to quantify biotinylated oligonucleotides, DNA hybridizations, and avidin in extracts of transgenic avidin maize. The detection limits of denatured and native streptavidin were 6 pM and 120 nM, respectively. The results demonstrated that streptavidin/avidin AdTS SWV is a sensitive and specific method for quantifying DNA and proteins in biological samples such as foods and tissue extracts, including genetically modified crops (avidin maize) and other plants in neighboring fields.  相似文献   
136.
A cyclic CCK8 analogue, cyclo(29,34)[Dpr(29),Lys(34)]-CCK8 (Dpr=L-2,3-diaminopropionic acid), has been designed on the basis of the NMR structure of the bimolecular complex between the N-terminal fragment of the CCK(A) receptor and its natural ligand CCK8. The conformational features of cyclo(29,34)[Dpr(29),Lys(34)]-CCK8 have been determined by NMR spectroscopy in aqueous solution and in water containing DPC-d(38) micelles (DPC=dodecylphosphocholine). The structure of the cyclic peptide in aqueous solution is found to be in a relaxed conformation, with the backbone and Dpr29 side chain atoms making a planar ring and the N-terminal tripeptide extending approximately along the plane of this ring. In DPC/water, the cyclic peptide adopts a "boat-shaped" conformation, which is more compact than that found in aqueous solution. The cyclic constraint between the Dpr29 side chain and the CCK8 carboxyl terminus (Lys34) introduces a restriction in the backbone conformational freedom. However, the interaction of cyclo(29,34)[Dpr(29),Lys(34)]-CCK8 with the micelles still plays an important role in the stabilisation of the bioactive conformation. A careful comparison of the NMR structure of the cyclic peptide in a DPC micelle aqueous solution with the structure of the rationally designed model underlines that the turn-like conformation in the Trp30-Met31 region is preserved, such that the Trp30 and Met31 side chains can adopt the proper spatial orientation to interact with the CCK(A) receptor. The binding properties of cyclo(29,34)[Dpr(29),Lys(34)]-CCK8 to the N-terminal receptor fragment have been investigated by fluorescence spectroscopy in a micellar environment. Estimates of the apparent dissociation constant, K(d), were in the range of 70-150 nM, with a mean value of 120+/-27 nM. Preliminary nuclear medicine studies on cell lines transfected with the CCK(A) receptor indicate that the sulfated-Tyr derivative of cyclo(29,34)[Dpr(29),Lys(34)]-CCK8 displaces the natural ligand with an IC(50) value of 15 microM.  相似文献   
137.
The current article examined the relationships among aging, intelligence, intracranial volume, and brain shrinkage in alcoholics and nonalcoholic controls. Magnetic resonance imaging was used to measure intracranial and cerebral volumes in 146 subjects with alcohol use disorders and 42 comparison subjects who were not alcoholic. The authors' findings show that performance on Block Design decreases as alcoholics age, and this decrease is predicted by brain shrinkage. This is consistent with a process of cumulative brain damage related to alcohol use. However, the authors' data also show that vocabulary does not decrease with age and is correlated with premorbid brain size as measured by intracranial volume, suggesting that lower verbal ability precedes heavy alcohol use and may be a risk factor for alcoholism. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
138.
This research compared adolescent daily smokers (n = 25) and nonsmokers (n = 26) on different measures of impulsivity. Assessments included question-based measures of delay (DDQ) and probability (PDQ) discounting, a measure of behavioral disinhibition (go-stop task), and a self-report measure of impulsivity (Barratt Impulsiveness Scale-Adolescent). Adolescent smokers were more impulsive on the DDQ and Barratt Impulsiveness Scale--Adolescent but not on the PDQ or the go-stop task. However, there was a significant interaction between smoking status and gender on the go-stop task, with male smokers performing less impulsively on this measure than male nonsmokers--an effect not observed with the female adolescents. These findings indicate that adolescents who smoke cigarettes are more impulsive with respect to some, but not all, types of impulsivity than are adolescents who do not smoke. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
139.
This work starts from modeling the scheduling of n jobs on m machines/stages as flowshop with buffers in manufacturing. A mixed-integer linear programing model is presented, showing that buffers of size n ? 2 allow permuting sequences of jobs between stages. This model is addressed in the literature as non-permutation flowshop scheduling (NPFS) and is described in this article by a disjunctive graph (digraph) with the purpose of designing specialized heuristic and metaheuristics algorithms for the NPFS problem. Ant colony optimization (ACO) with the biologically inspired mechanisms of learned desirability and pheromone rule is shown to produce natively eligible schedules, as opposed to most metaheuristics approaches, which improve permutation solutions found by other heuristics. The proposed ACO has been critically compared and assessed by computation experiments over existing native approaches. Most makespan upper bounds of the established benchmark problems from Taillard (1993) and Demirkol, Mehta, and Uzsoy (1998) with up to 500 jobs on 20 machines have been improved by the proposed ACO.  相似文献   
140.
This article proposes to test the feasibility of long-term surface deformation monitoring based on synthetic aperture radar (SAR) interferometry on carbon dioxide (CO2) storage sites with land cover representative of potential European injection sites (agricultural or forests with minimum built-up land cover). Because no operational injection site is currently active in Europe, a SAR data set (based on EnviSAT–ASAR spaceborne data) is simulated by combining SAR scenes acquired over a potential future European injection site with deformation measurements from SAR analysis carried out on the In-Salah (Algeria) CO2 injection demonstrator site. The study shows that under such conditions, both persistent scatterer interferometry (PSI) and diffuse scatterer (DS) interferometry appear insufficient to provide a sufficiently dense measurement network to characterize surface deformation correctly. Alternative solutions, to be investigated in further studies, include the use of data archives with shorter acquisition time spans (e.g. Sentinel-1 data when available) or installation of corner reflectors. The cost of the latter mixed space/ground solution must be evaluated with respect to conventional ground-based measurement methods in the proposed context.  相似文献   
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