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91.
The hypothesis was examined that organizational specificity of biodata validity results from the methods typically used to select and key items. In this study, items were initially screened for job relevance, keying was based on large samples from multiple organizations, and items were retained only if they showed validity across organizations. Cross-validation was performed on approximately 11,000 first-line supervisors in 79 organizations. The resulting validities were meta-analyzed across organizations, age levels, sex, and levels of education, supervisory experience, and company tenure. In all cases, validities were generalizable. Validities were also stable across time and did not appear to stem from measurement of knowledge, skills, or abilities acquired through job experience. Finally, these results provide additional evidence against the hypothesis of situational specificity of validities, the first large-sample evidence in a noncognitive domain. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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In this study we concentrate on qualitative topological analysis of the local behavior of the space of natural images. To this end, we use a space of 3 by 3 high-contrast patches ℳ. We develop a theoretical model for the high-density 2-dimensional submanifold of ℳ showing that it has the topology of the Klein bottle. Using our topological software package PLEX we experimentally verify our theoretical conclusions. We use polynomial representation to give coordinatization to various subspaces of ℳ. We find the best-fitting embedding of the Klein bottle into the ambient space of ℳ. Our results are currently being used in developing a compression algorithm based on a Klein bottle dictionary.  相似文献   
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One hundred ninety-five boys with attention-deficit/hyperactivity disorder (ADHD) were compared with 73 comparison boys (M=9.83 years, SD=1.30) on self-perceptions relative to a teacher-rated criterion. Emphasis was placed on ADHD subgroup comparisons according to level of aggression, academic achievement, and depression compared with control boys. Consistent with the authors' prediction, ADHD boys overestimated relative to teacher report, more than did controls, in the scholastic competence, social acceptance, and behavioral conduct domains. Examination of discrepancy scores (child rating--teacher rating) by comorbidity subgroups suggested that aggressive and low-achieving ADHD boys tended to overestimate their competence the most in the domains in which they were the most impaired. Results are discussed in terms of prior literature on "positive illusions" in ADHD children. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
95.
It is commonly assumed that attitudes and behaviours need to be modified to secure a sustainable energy future. This paper examines insights from the social sciences in this extensive field. Alongside instruments such as regulation and economic measures, government campaigns have sought to ‘educate’ the public. However, such ‘information deficit’ models have been criticised on theoretical and pragmatic grounds. In the area of energy consumption, there is a need to take account of the physical, social, cultural and institutional contexts that shape and constrain people's choices, and for a richer understanding of opposition to energy facility siting, which has often been (inadequately) characterised as ‘NIMBYism’. Recent work also points to the need for more deliberation and better communication between decision-makers, technical experts, other stakeholders and the public. Predicting future developments in the field is challenging but attention is likely to focus on aspects of policy learning, a more critical examination of the ‘deliberative turn’, and the need for a systemic approach to complex socio-economic and socio-technical systems. The consistency of government objectives across all policy spheres is likely to provide an important avenue for future research.  相似文献   
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This is the first in-depth study examining the effect of morphology on the performance of 2-aminopyridine (2-apy) imprinted polymers. A series of polymers were prepared by varying the amount of crosslinking monomer (EGDMA) whilst the other polymer components remained constant. Physical characterisation was carried out using conventional techniques, such as nitrogen sorption porosimetry and solvent swelling studies. The use of a novel thermal desorption GC-MS technique suggested higher levels of polymer degradation with prolonged exposure to elevated temperatures for those polymers formed with lower amounts of EGDMA. The thermal desorption GC-MS profiles obtained correlated with the physical characteristics of the polymers, where higher levels of polymer bleed was found to occur with larger average pore diameters. Polymer physical characteristics were also found to correlate with the binding parameters (number of binding sites and polymer-template association energy) obtained from the Langmuir-Freundlich Isotherm (L-FI) and affinity distribution spectra (AD). The flexibility of the polymers formed from lower amounts of EGDMA combined the swelling effect of the solvents on the polymers resulted in an increase in affinity, which was both specific and non-specific in nature.  相似文献   
99.
Recent crystallographic studies on Escherichia coli inorganic pyrophosphatase (E-PPase) have identified three Mg2+ ions/enzyme hexamer in water-filled cavities formed by Asn24, Ala25, and Asp26 at the trimer-trimer interface (Kankare, J., Salminen, T., Lahti, R., Cooperman, B., Baykov, A. A., and Goldman, A. (1996) Biochemistry 35, 4670-4677). Here we show that D26S and D26N substitutions decrease the stoichiometry of tight Mg2+ binding to E-PPase by approximately 0.5 mol/mol monomer and increase hexamer stability in acidic medium. Mg2+ markedly decelerates the dissociation of enzyme hexamer into trimers at pH 5.0 and accelerates hexamer formation from trimers at pH 7.2 with wild type E-PPase and the N24D variant, in contrast to the D26S and D26N variants, when little or no effect is seen. The catalytic parameters describing the dependences of enzyme activity on substrate and Mg2+ concentrations are of the same magnitude for wild type E-PPase and the three variants. The affinity of the intertrimer site for Mg2+ at pH 7.2 is intermediate between those of two Mg2+ binding sites found in the E-PPase active site. It is concluded that the metal ion binding site found at the trimer-trimer interface of E-PPase is a high affinity site whose occupancy by Mg2+ greatly stabilizes the enzyme hexamer but has little effect on catalysis.  相似文献   
100.
ABSTRACT

Human hacking is a nontechnical kind of intrusion that relies heavily on human manipulation. Its impact is continuously giving serious concern in the Information technology arena which has often been undermined due to the ease with which this technique is widely used to infiltrate networks through unsuspecting individuals that are undeniably considered the “weakest link” in the security circle. Security awareness that brings about behavioral change, reduces employees' vulnerability, and protects against threats exploiting employees' vulnerability having a positive impact overall on risks related to information assets. Strategies for developing and implementing a successful information security awareness program are presented in this article, which also provides an introduction to the subject of human hacking while discussing the various counter-measures available to minimize the likelihood of such occurrences and their financial, reputation, psychological, and legal ramifications.  相似文献   
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