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61.
Meta-analysis was used to aggregate results from studies examining the relationship between intelligence and leadership. One hundred fifty-one independent samples in 96 sources met the criteria for inclusion in the meta-analysis. Results indicated that the corrected correlation between intelligence and leadership is .21 (uncorrected for range restriction) and .27 (corrected for range restriction). Perceptual measures of intelligence showed stronger correlations with leadership than did paper-and-pencil measures of intelligence. Intelligence correlated equally well with objective and perceptual measures of leadership. Additionally, the leader's stress level and the leader's directiveness moderated the intelligence-leadership relationship. Overall, results suggest that the relationship between intelligence and leadership is considerably lower than previously thought. The results also provide meta-analytic support for both implicit leadership theory and cognitive resource theory. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
62.
In a nonclinical sample of 395 young adults, the authors evaluated the relations between major personality traits, Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV; American Psychiatric Association, 1994) personality disorder symptoms, and DSM-IV alcohol use disorders (AUDs). Consistent with previous findings, traits related to disinhibition and negative affectivity were consistently associated with AUDs, as were Cluster B personality disorder symptoms (especially antisocial and borderline disorder symptoms). Multivariate analyses revealed that Cluster B symptoms were significantly associated with AUDs above and beyond what was accounted for by personality traits. Further, the authors found differential patterns of relations between other substance use disorders (SUDs; i.e., tobacco dependence and drug use diagnoses) and personality disorder symptoms. Overall, these results suggest that personality disorder symptoms predict unique variance in SUDs that reflect maladaptive aspects of personality traits. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
63.
JeriesAbou-Hanna Timothy E. McGreevy Saurin Majumdar 《Nuclear Engineering and Design》2004,229(2-3):175-187
Prediction of failure pressures of cracked steam generator tubes of nuclear power plants is an important ingredient in scheduling inspection and repair of tubes. Prediction is usually based on nondestructive evaluation (NDE) of cracks. NDE often reveals two neighboring cracks. If the cracks interact, the tube pressure under which the ligament between the two cracks fails could be much lower than the critical burst pressure of an individual equivalent crack. The ability to accurately predict the ligament failure pressure, called “coalescence pressure,” is important. The failure criterion was established by nonlinear finite element model (FEM) analyses of coalescence of two 100% through-wall collinear cracks. The ligament failure is precipitated by local instability of the ligament under plane strain conditions. As a result of this local instability, the ligament thickness in the radial direction decreases abruptly with pressure. Good correlation of FEM analysis results with experimental data obtained at Argonne National Laboratory’s Energy Technology Division demonstrated that nonlinear FEM analyses are capable of predicting the coalescence pressure accurately for 100% through-wall cracks. This failure criterion and FEA work have been extended to axial cracks of varying ligament width, crack length, and cases where cracks are offset by axial or circumferential ligaments. 相似文献
64.
John E. Rash Timothy J. A. Johnson C. Sue Hudson F. Dennis Giddings William F. Graham Mohyee E. Eldefrawi 《Journal of microscopy》1982,128(2):121-138
Three methods are described for direct post-fracture, post-shadow labelling of individual classes of intramembrane particles (IMPs) in freeze-fracture replicas of biological membranes. The P-face IMPs corresponding to the acetylcholine receptor complexes (AChRs) of vertebrate neuroeffector junctions are identified by post-replication labelling with ferritin-antibody complexes and with neurotoxin-biotin-avidin-colloidal gold affinity ligands. (The freeze-etch nomenclature of Branton et al., 1975, is used in this report.) These post-shadow labelling techniques resemble conventional en bloc labelling techniques except that the labelling reagents must penetrate a thin but discontinuous layer of platinum superimposed on the molecules of interest. In the ‘sectioned labelled-replica technique’, the replicated and labelled tissues are stained, embedded in plastic and sectioned parallel to the replica-tissue interfaces. In the direct ‘labelled-replica techniques’, the replicated and labelled samples are freeze-dried or critical point dried, the labelled surfaces are stabilized by carbon coating, and the underlying tissues are dissolved, allowing the labelled-replicas to be examined as conventional freeze-fracture replicas. The unshadowed side of each AChR IMP is shown to retain sufficient biochemical information to permit both immunospecific and neurotoxin specific labelling despite formaldehyde fixation, freezing, fracturing, platinum shadowing, and thawing in aqueous media. A new mixed ferricyanide-osmium staining method reveals electron opaque structures spanning the membrane bilayer in the same size, number and distribution as the labelled IMPs. These experiments demonstrate the feasibility of identifying individual IMPs in freeze-fracture replicas and may allow the identification of specific membrane lesions in human disease. 相似文献
65.
The five articles that make up the bulk of this special issue collectively illustrate new methods for examining the utility of sub-test and scale-level profile analysis. By necessity they are preliminary, but they illustrate methods that may indeed prove useful and may help resolve this divide between research and practice. This special issue grew out of a symposium conceived and organized by Cecil Reynolds at the American Psychological Association in 1998. The articles and one of the commentaries in this special issue are extensions of that symposium. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
66.
Li Ding Timothy Lebo John S. Erickson Dominic DiFranzo Gregory Todd Williams Xian Li James Michaelis Alvaro Graves Jin Guang Zheng Zhenning Shangguan Johanna Flores Deborah L. McGuinness James A. Hendler 《Journal of Web Semantics》2011,9(3):325-333
International open government initiatives are releasing an increasing volume of raw government datasets directly to citizens via the Web. The transparency resulting from these releases not only creates new application opportunities but also imposes new burdens inherent to large-scale distributed data integration, collaborative data manipulation and transparent data consumption. The Tetherless World Constellation (TWC) at Rensselaer Polytechnic Institute (RPI) has developed the Semantic Web-based TWC LOGD portal to support the deployment of linked open government data (LOGD). The portal is both an open source infrastructure supporting linked open government data production and consumption and a vibrant community portal that educates and serves the growing international open government community of developers, data curators and end users. This paper motivates and introduces the TWC LOGD Portal and highlights innovative aspects and lessons learned. 相似文献
67.
Samuel J. Moseley Christine A. Allen Nicholas Costin Richard Kelley Caroline Kilbourne Timothy Miller 《Journal of Low Temperature Physics》2008,151(1-2):418-423
We have developed an automated die-scale process for the attachment of X-ray absorbers onto microcalorimeters. Here, we describe
the process for the production of absorber tiles on a handle wafer, their attachment to the microcalorimeter, and the removal
of the supporting handle wafer. The process is shown to be a robust path to large format arrays of microcalorimeters.
相似文献
68.
The bioanode is the defining feature of microbial fuel cell (MFC) technology and often limits its performance. In the current work, we report the engineering of a novel hierarchically porous architecture as an efficient bioanode, consisting of biocompatible chitosan and vacuum-stripped graphene (CHI/VSG). With the hierarchical pores and unique VSG, an optimized bioanode delivered a remarkable maximum power density of 1530 mW m(-2) in a mediator-less MFC, 78 times higher than a carbon cloth anode. 相似文献
69.
Peri SR Akgun B Satija SK Jiang H Enlow J Bunning TJ Foster MD 《ACS applied materials & interfaces》2011,3(9):3375-3383
Tailoring the structure of films deposited by plasma-enhanced chemical vapor deposition (PECVD) to specific applications requires a depth-resolved understanding of how the interface structures in such films are impacted by variations in deposition parameters such as feed position and plasma power. Analysis of complementary X-ray and neutron reflectivity (XR, NR) data provide a rich picture of changes in structure with feed position and plasma power, with those changes resolved on the nanoscale. For plasma-polymerized octafluorocyclobutane (PP-OFCB) films, a region of distinct chemical composition and lower cross-link density is found at the substrate interface for the range of processing conditions studied and a surface layer of lower cross-link density also appears when plasma power exceeds 40 W. Varying the distance of the feed from the plasma impacts the degree of cross-linking in the film center, thickness of the surface layer, and thickness of the transition region at the substrate. Deposition at the highest power, 65 W, both enhances cross-linking and creates loose fragments with fluorine content higher than the average. The thickness of the low cross-link density region at the air interface plays an important role in determining the width of the interface built with a layer subsequently deposited atop the first. 相似文献
70.
James A. Dolan Raphael Dehmel Angela Demetriadou Yibei Gu Ulrich Wiesner Timothy D. Wilkinson Ilja Gunkel Ortwin Hess Jeremy J. Baumberg Ullrich Steiner Matthias Saba Bodo D. Wilts 《Advanced materials (Deerfield Beach, Fla.)》2019,31(2)
Optical metamaterials offer the tantalizing possibility of creating extraordinary optical properties through the careful design and arrangement of subwavelength structural units. Gyroid‐structured optical metamaterials possess a chiral, cubic, and triply periodic bulk morphology that exhibits a redshifted effective plasma frequency. They also exhibit a strong linear dichroism, the origin of which is not yet understood. Here, the interaction of light with gold gyroid optical metamaterials is studied and a strong correlation between the surface morphology and its linear dichroism is found. The termination of the gyroid surface breaks the cubic symmetry of the bulk lattice and gives rise to the observed wavelength‐ and polarization‐dependent reflection. The results show that light couples into both localized and propagating plasmon modes associated with anisotropic surface protrusions and the gaps between such protrusions. The localized surface modes give rise to the anisotropic optical response, creating the linear dichroism. Simulated reflection spectra are highly sensitive to minute details of these surface terminations, down to the nanometer level, and can be understood with analogy to the optical properties of a 2D anisotropic metasurface atop a 3D isotropic metamaterial. This pronounced sensitivity to the subwavelength surface morphology has significant consequences for both the design and application of optical metamaterials. 相似文献