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91.
The engineering and construction industry has evolved to a task-centric approach to evaluating the effectiveness of projects. However, a narrow task-based view of project network logic neglects the coordination of communication and knowledge exchanges across the project organizational network. This paper departs from traditional approaches to introduce a new approach to assessing project effectiveness that focuses on alignment of actual knowledge exchanges with knowledge exchange requirements across task-organization network dyads. A new modeling approach is introduced, called Project Network Interdependency Alignment. Project Network Interdependency Alignment identifies potentially excessive or insufficient communication and knowledge exchanges that can make projects ineffective. The modeling approach is introduced and retrospectively validated by using a building renovation construction project. The case study demonstrates that the approach can provide project managers with the capacity to analyze task and organizational network interdependence on projects and the critical capability to identify misalignments that impede project effectiveness. 相似文献
92.
Multiple sclerosis (MS) is an autoimmune disease of the central nervous system (CNS) characterized by an inappropriate inflammatory reaction resulting in widespread myelin injury along white matter tracts. Neurological impairment as a result of the disease can be attributed to immune-mediated injury to myelin, axons and mitochondria, but the molecular mechanisms underlying the neuropathy remain incompletely understood. Incomplete mechanistic knowledge hinders the development of therapies capable of alleviating symptoms and slowing disease progression in the long-term. Recently, oxidative stress has been implicated as a key component of neural tissue damage prompting investigation of reactive oxygen species (ROS) scavengers as a potential therapeutic option. Despite the establishment of oxidative stress as a crucial process in MS development and progression, ROS scavengers have had limited success in animal studies which has prompted pursuit of an alternative target capable of curtailing oxidative stress. Acrolein, a toxic β-unsaturated aldehyde capable of initiating and perpetuating oxidative stress, has been suggested as a viable point of intervention to guide the development of new treatments. Sequestering acrolein using an FDA-approved compound, hydralazine, offers neuroprotection resulting in dampened symptom severity and slowed disease progression in experimental autoimmune encephalomyelitis (EAE) mice. These results provide promise for therapeutic development, indicating the possible utility of neutralizing acrolein to preserve and improve neurological function in MS patients. 相似文献
93.
Analysis of Residential Irrigation Distribution Uniformity 总被引:1,自引:0,他引:1
Melissa C. Baum Michael D. Dukes Grady L. Miller 《Canadian Metallurgical Quarterly》2005,131(4):336-341
Irrigation has become commonplace for residential homeowners desiring high quality landscapes in Florida. The goal of this project was to document irrigation system uniformity in Central Florida and to quantify distribution uniformity of residential sprinkler equipment under controlled conditions. The catch-can testing procedure used was a modified version of both the American Society of Agricultural Engineers standard and Florida Mobile Irrigation Laboratory (MIL) procedures. The modified version included a larger sample size to ensure complete sample collection over the entire irrigated area. The standard MIL procedure may overestimate the uniformity for residential systems. From the tests on residential irrigation systems, the average low quarter distribution uniformity (DUlq) value was calculated as 0.45. Rotary sprinklers resulted in significantly higher DUlq compared to fixed pattern spray heads with 0.49 compared to 0.41, respectively. From uniformity tests performed on rotor and spray heads under ideal conditions, rotor heads had more uniform distributions than the spray heads of 0.55 compared to 0.49, respectively. Spray heads had better uniformity when fixed quarter circle nozzles were used as opposed to adjustable nozzles. Both residential irrigation system and controlled tests resulted in (DUlq) at the low end of industry guidelines. Residential irrigation system uniformity can be improved by minimizing the occurrence of low pressure in the irrigation system and by ensuring proper spacing is used in design and installation. 相似文献
94.
The current study examined the fit of a 2 × 2 achievement goal model among a diverse sample of nearly 700 10th-grade students, distinguishing between both mastery and performance goals and approach and avoidance orientations. Additionally, relationships between achievement goals and GPA and intrinsic value of school were examined, and adolescents' interpretations of daily school experiences and feelings were found to mediate these relationships. Together, these findings suggest that experiences in adolescents' daily lives help explain the relationship between goals and achievement outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
The authors used a path model to test the hypothesis that emotional closeness and conflict between adult–child caregivers (N?=?90) and their impaired parents mediated the impact of the parents' functional and cognitive impairment on the caregivers' subjective stress, subjective effectiveness, and depression. Closeness mediated the relationship between cognitive impairment and both stress and effectiveness, whereas conflict mediated cognitive impairment for all 3 outcomes and generally accounted for more variance. There was limited evidence that functional impairment was mediated by the quality of the relationship. Results highlight the importance of both positive and negative ties as intervening mechanisms influencing caregivers' well-being, especially in the presence of cognitive dysfunction. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
96.
Carew Tania Giovannetti; Lamar Melissa; Cloud Blaine S.; Grossman Murray; Libon David J. 《Canadian Metallurgical Quarterly》1997,11(3):400
The underlying mechanisms for impaired output on letter (F, A, and S) and category (e.g., animal) word list generation (WLG) tasks in subcortical ischemic vascular dementia (IVD) were investigated. Normal control (NC) and Alzheimer's disease (AD) participants were also studied. IVD and NC participants performed better on category than letter WLG tasks, whereas the opposite was observed among AD participants. IVD participants produced fewer responses than AD participants on letter WLG tasks, but there was no difference between AD and IVD participants on the "animal" WLG task. AD participants scored lower than IVD and NC participants on animal WLG indexes measuring semantic knowledge. There were few differences between IVD and NC participants. The reduced output on the animal WLG task for IVD participants is consistent with search-retrieval deficits. The reduced output of AD participants may be caused by degraded semantic knowledge. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
97.
The authors agree with the main elements of M. Bruck and S. J. Ceci's (see record 1996-09956-001) amicus curiae brief for the case of State v. Michaels, but they believe that 4 specific aspects of child sexual abuse investigations deserve a more constructive emphasis. Research has tended to concentrate on the suggestibility of children and neglected other topics that may be of great utility to those who investigate suspected cases of child sexual abuse. More attention should have been paid in the brief to the complexities of assessment and the special characteristics of the Wee Care case. Too much emphasis has been placed on children and not nearly enough attention on remedial actions to minimize the problems associated with suggestion. Finally, research shows that it may be possible to develop reliable and valid techniques to assess child sexual abuse allegations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
98.
This article replies to comments by J. C. Gonsiorek (see record 84-33291), P. Orr (see record 84-33300), and L. S. Brown (see record 84-33284 ) on M.J. Layman and J.R. McNamara's (see record 84-33293) work on remediation and ethics violations. The authors acknowledge various distinctions they have introduced but continue to argue that sexual violations are outstandingly egregious. They agree that making amends is important but wonder about the practicalities of working this into rehabilitation. Lack of empirical knowledge about what is prescribed for remediation is reemphasized. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
99.
Mainstream psychologists have not pursued sexology with the enthusiasm aimed at other areas of psychological research. Ambivalence is evident in the ideological marginalization of sexology by mainstream psychology. The authors argue that scientific conflicts between the disciplines in part reflect divergent interpretations of how each discipline approaches the scientific method. By aligning psychology with positivism and sexology with postpositivism, a discussion of cultural, scientific, and normative conflicts between the two disciplines is presented as evidence for these differences in scientific ideology. To address these conflicts, future directions for scientific progress are proposed for sexology and psychology. Specifically, by capitalizing on the strengths of each discipline, collaboration can lead to the validation of sexology as a science and the enhancement of both disciplines. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
100.
Hugenberg Kurt; Bodenhausen Galen V.; McLain Melissa 《Canadian Metallurgical Quarterly》2006,91(6):1020
Three studies investigated how inclusion versus exclusion strategies differentially lead to stereotypic decisions. In inclusion strategies, suitable targets are selected from a list of candidates, whereas in exclusion strategies, unsuitable candidates are eliminated. Across 2 separate target domains (Study 1: male and female politicians; Studies 2 and 3: African American and European American basketball players), exclusion strategies, as compared with inclusion strategies, elicited higher levels of both sensitivity stereotyping (i.e., greater difficulty distinguishing among members of stereotyped groups) and criterion stereotyping (i.e., setting different decision thresholds for judging members of different groups; see M. R. Banaji & A. G. Greenwald, 1995). Thus, the strategy used during decision making can influence the final decision via 2 theoretically distinct stereotyping mechanisms. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献