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1.
This study provides a meta-analysis of research on the associations between relationship conflict, task conflict, team performance, and team member satisfaction. Consistent with past theorizing, results revealed strong and negative correlations between relationship conflict, team performance, and team member satisfaction. In contrast to what has been suggested in both academic research and introductory textbooks, however, results also revealed strong and negative (instead of the predicted positive) correlations between task conflict, team performance, and team member satisfaction. As predicted, conflict had stronger negative relations with team performance in highly complex (decision making, project, mixed) than in less complex (production) tasks. Finally, task conflict was less negatively related to team performance when task conflict and relationship conflict were weakly, rather than strongly, correlated. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
2.
STUDY OBJECTIVE: To determine if the addition of alfentanil to propofol is more effective than propofol alone to provide adequate conditions for placement of a retrobulbar block prior to cataract surgery. DESIGN: Randomized, double-blinded study. SETTING: Outpatients at a university hospital. PATIENTS: 40 adult ASA physical status I, II, and III outpatients scheduled for elective cataract surgery. INTERVENTIONS: Patients were randomly assigned to receive one of four drug combinations prior to the placement of a retrobulbar block: Group 1, propofol alone; Group 2, alfentanil 5 micrograms/kg plus propofol; Group 3, alfentanil 10 micrograms/kg plus propofol; Group 4, alfentanil 15 micrograms/kg plus propofol. All patients were preoxygenated by face mask for two minutes prior to drug administration. The quality of conditions for block placement were determined by: (1) assessing the amount of movement by the patients while the block needle was in place, (2) cooperativeness of the patients during the operation, (3) hemodynamic side effects, (4) incidence and severity of respiratory depression, (5) incidence of nausea and vomiting, (6) recall of placement of the block, and (7) time to discharge from the hospital. Measurements and Main Results: The addition of alfentanil to propofol for sedation prior to placement of the retrobulbar block resulted in a dose-dependent reduction in movement by the patients. However, the highest dose of alfentanil (15 micrograms/kg) resulted in the greatest frequency (40% of the patients in this group) of respiratory depression (SpO2 < 90%). All patients were cooperative during the operation and responsive to verbal command within 5 minutes of placement of the block. In addition, all of the patients denied being nauseated, having vomited, or recalling block placement in the recovery room or the next day. CONCLUSIONS: The combination of alfentanil and propofol may be used to sedate patients in order to limit movement and provide a cooperative, alert patient with stable hemodynamics and limited respiratory depression during placement of retrobulbar block prior to ophthalmic surgery. However, excessive dosage of these drugs may result in hazardous respiratory depression in this patient population. 相似文献
3.
M Belkin MS Conte MC Donaldson JA Mannick AD Whittemore 《Canadian Metallurgical Quarterly》1995,21(2):282-93; discussion 293-5
PURPOSE: To determine the optimal surgical strategies in reoperative infrainguinal bypass, we reviewed our results in 300 consecutive secondary bypasses in 251 patients operated on between Jan. 1, 1975, and Nov. 1, 1993. METHODS: There were 168 men (67%) and 83 women (33%), with a mean age of 64.8 years and a typical distribution of risk factors including smoking (76.4%), diabetes (33.7%), and coronary artery disease (47.1%). The indications for surgery were limb-threatening ischemia in 83.5% and severe claudication in 16.5% of patients. The majority of conduits (n = 213) were autogenous vein and were composed of a single segment of greater saphenous vein in 121 bypasses (57%) and various alternative veins including composite, arm, and lesser saphenous vein in 92 bypasses (43%). Prosthetic conduits included 69 polytetrafluoroethylene, 16 umbilical vein, and two Dacron grafts. RESULTS: There was one perioperative death (0.3%) and a 25% total morbidity rate including a 1.7% myocardial infarction rate. There was a 28.6% early (< 30 days) graft failure and 10.7% early amputation rate for prosthetic bypass grafts compared with 13.6% early graft failure and 5.6% early amputation rates for vein grafts. Autogenous vein bypasses had higher 5-year secondary patency rates than had prosthetic grafts (51.5% +/- 4.6% vs 27.4% +/- 6.1%, p < 0.001). Results with autogenous vein bypass improved significantly from the 1975 to 1984 to the 1985 to 1993 interval with 5-year secondary patency rates increasing from 38.3% +/- 6.9% to 59.1% +/- 5.8% (p = 0.017) and 5-year limb-salvage rates increasing from 40.4% +/- 7.6% to 72.4% +/- 6.6% (p < 0.001). Vein grafts to the popliteal and tibial outflow levels had equivalent long-term results. Vein grafts completed for claudication demonstrated results superior to those for limb salvage, with a 5-year secondary patency rate of 75.8% +/- 8.1% versus 52.3% +/- 7.9% (p = 0.048). Secondary autogenous vein bypass grafting performed after early primary graft failure (< 3 months) did particularly poorly, with only a 27.2% +/- 7.7% 4-year secondary patency rate. Greater saphenous veins tended to perform better than alternative vein bypasses, with a 5-year secondary patency rate of 68.5% +/- 6.0% compared with 48.3% +/- 10.5% (p = 0.09) and a 5-year limb-salvage rate of 77.8% +/- 7.4% versus 54.2% +/- 11.8% (p = 0.046). CONCLUSIONS: When patients suffer a recurrence of limb-threatening ischemia at the time of infrainguinal graft failure, aggressive attempts at secondary revascularization with autogenous vein are warranted based on the low surgical morbidity and mortality rates and the improved patency and limb salvage rates that are currently attainable. 相似文献
4.
Leung V.C.M. Qian N. Malyan A.D. Donaldson R.W. 《Selected Areas in Communications, IEEE Journal on》1994,12(8):1376-1388
A distributed circuit-switched approach for supporting the deployment of high speed wireless personal communication services in urban areas through the interconnection of base stations via metropolitan area networks (MANs) is proposed. Broadband MANs minimize traffic congestion by dynamic sharing of link capacity and by serving as distributed switches for partitioning call control functions. While the DQDB protocol readily supports distributed packet-switching over the IEEE 802.6 MAN, isochronous traffic such as voice and video is best supported by circuit-switched connections. The authors present an enhanced bi-state pre-arbitrated (PA) transport mechanism, and associated call control and handoff management techniques, which enable distributed circuit-switching over the MAN. These capabilities are not currently addressed in the 802.6 standards. The bi-state PA transport mechanism facilitates statistical multiplexing of variable rate isochronous traffic sources. The network capacity is constrained by the call setup delay performance, and is analyzed by simulations. Alternative signaling architectures, involving different placements of call control network elements, are evaluated. The effects of erasure nodes, and close bus versus open bus architectures, are considered. The overlap inter-MAN call setup procedure is proposed to reduce delays. Different call handoff procedures are formulated according to the type of handoff and the resulting change in call connectivity. Most handoffs are intra-MAN, requiring simple procedures with short delays 相似文献
5.
Hemanshu Bhatt Kimberly Y. Donaldson D. P. H. Hasselman Kenneth Chyung Mark P. Taylor 《Journal of the American Ceramic Society》1991,74(6):1463-1465
A study concerning the effect of fiber orientation on the thermal conductivity of a uniaxial carbon-fiber-reinforced borosilicate glass was conducted. For thin specimens, and thick specimens with specimen sides cut parallel to the fiber direction, the dependence of thermal conductivity on fiber orientation showed excellent agreement with theoretical behavior predicted for a composite infinite in extent. In contrast, the thermal conductivity data for rectangular thick specimens fell well below the data for the thin and angled specimens. For fiber orientation of 45° and higher, at which the heat was directed toward the side of the specimen rather than across, the thermal conductivity values showed excellent agreement with theoretical behavior predicted for a finite composite strip with insulated sides. 相似文献
6.
Kaslow Nadine J.; Rubin Nancy J.; Forrest Linda; Elman Nancy S.; Van Horne Barbara A.; Jacobs Sue C.; Huprich Steven K.; Benton Sherry A.; Pantesco Victor F.; Dollinger Stephen J.; Grus Catherine L.; Behnke Stephen H.; Miller David S. Shen; Shealy Craig N.; Mintz Laurie B.; Schwartz-Mette Rebecca; Van Sickle Kristi; Thorn Beverly E. 《Canadian Metallurgical Quarterly》2007,38(5):479
Working collaboratively, psychologist educators and trainers at the doctoral, internship, and postdoctoral levels; credentialers; practitioners; and students offer 8 proposals for psychologists to consider in recognizing, assessing, and intervening with problems of professional competence in students and practicing professionals. In the proposals, the authors address the following topics: definitions and categories; preparing the system; self-assessment; remediation; diversity; communication across various levels of the system; confidentiality; and ethical, regulatory, and legal underpinnings. They also propose future directions for the assessment of problems in professional competence in both students and practicing psychologists. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
7.
Assessed the escalations in substance use over 3 yrs among 246 adolescent children of alcoholics (COAs) and 208 controls (aged 10.5–15.5 yrs). Older COAs showed the steepest escalations in drug use. Younger COAs whose fathers had continuing alcohol-related consequences showed the greatest escalations in alcohol use. Ss' beliefs about drinking restraint were related to their alcohol and drug use. Those whose alcoholic fathers had no continuing alcohol-related consequences showed the strongest relations between substance use and self-control reasons for limiting drinking, perceived risk for future drug problems, and seeing the negative effects of alcohol on someone else. These adolescents may be deterred from substance use escalations because of particular parental characteristics (e.g., mild forms of paternal alcoholism) or because of their beliefs about substance use. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
Allen John J.; Chapman Loren J.; Chapman Jean P.; Vuchetich John P.; Frost Laurie A. 《Canadian Metallurgical Quarterly》1987,96(2):83
Correlates of psychotic and psychoticlike symptoms were examined in 60 college students who scored deviantly high on the Perceptual Aberration Scale. High scorers on this scale who also scored high on both the Impulsive Nonconformity Scale and the Depression subscale of the General Behavior Inventory (GBI) showed the most deviant psychotic and psychoticlike symptoms. Moreover, performance on a task of referential communication, the Password Task, was significantly related to such symptoms. The Perceptual Aberration Scale, the Impulsive Nonconformity Scale, and the GBI Depression subscale are recommended for concurrent use in mass screening to select individuals likely to exhibit psychotic or psychoticlike symptoms. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
Clotilde LM Bernard C Sequera DE Karmali A Fusellier A Carter JM 《Journal of laboratory automation》2012,17(4):309-314
Conventional enzyme-linked immunosorbent assay (ELISA) is a gold standard for screening antibodies and testing for protein or antigen presence. A significant limitation of this assay resides in the fact that only one analyte can be assessed per microplate well. Here, we describe and investigate a new technology consisting of an automated ELISA system in which up to 10 analytes can be measured within one single well, thus improving productivity, accuracy, and repeatability by reducing the amount of human labor required. Another strength of the platform is that a user can load any necessary sets/subsets of beads to perform required assays, with improved flexibility compared to manufactured-loaded arrays for multiplex analysis. We also demonstrate that this system can be used to determine the pathogenicity (i.e., presence of Shiga toxins) and serotype (i.e., Escherichia coli O157) of E. coli isolates. 相似文献
10.
Gilles Thibault Gilles Paintaud Hsueh Cheng Sung Laurie Lajoie Edouard Louis the GETAID Celine Desvignes Herv Watier Valrie Gouilleux-Gruart David Ternant 《International journal of molecular sciences》2021,22(11)
The FcγRIIA/CD32A is mainly expressed on platelets, myeloid and several endothelial cells. Its affinity is considered insufficient for allowing significant binding of monomeric IgG, while its H131R polymorphism (histidine > arginine at position 131) influences affinity for multimeric IgG2. Platelet FcγRIIA has been reported to contribute to IgG-containing immune-complexe clearance. Given our finding that platelet FcγRIIA actually binds monomeric IgG, we investigated the role of platelets and FcγRIIA in IgG antibody elimination. We used pharmacokinetics analysis of infliximab (IgG1) in individuals with controlled Crohn’s disease. The influence of platelet count and FcγRIIA polymorphism was quantified by multivariate linear modelling. The infliximab half-life increased with R allele number (13.2, 14.4 and 15.6 days for HH, HR and RR patients, respectively). It decreased with increasing platelet count in R carriers: from ≈20 days (RR) and ≈17 days (HR) at 150 × 109/L, respectively, to ≈13 days (both HR and RR) at 350 × 109/L. Moreover, a flow cytometry assay showed that infliximab and monomeric IgG1 bound efficiently to platelet FcγRIIA H and R allotypes, whereas panitumumab and IgG2 bound poorly to the latter. We propose that infliximab (and presumably any IgG1 antibody) elimination is partly due to an unappreciated mechanism dependent on binding to platelet FcγRIIA, which is probably tuned by its affinity for IgG2. 相似文献