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1.
The performance of a cross-functional team depends on the skillful and innovative combination of information and expertise from all team members. Communication is the medium through which team members share the information required for successful amalgamation. In this work, we postulate that both high and low levels of team communication can impede team performance, thus leading to a curvilinear relationship between team performance and team communication. To test this hypothesis, the relationships between face-to-face, e-mail, and telephone communication and team performance were examined for 60 cross-functional project teams. E-mail and face-to-face communication were curvilinearly associated with performance, but telephone communication was not. Further analysis of the communication frequency between colocations showed that e-mail is the only medium for which usage increased with distance.  相似文献   
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A mathematical model for predicting the temperature in a homogeneous layer of dry snow is presented. The model, which is physically based, is capable of predicting diurnal temperature behaviour at the snow surface and at any depth within a snow layer given the variation in a limited set of meteorological parameters over that period. A sensitivity analysis is performed to determine the important parameters in the prediction of snow surface temperatures. These are found to be consistent with simple physical reasoning.  相似文献   
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More frequent dialysis is thought to be associated with increased heparin requirements; however, limited data are available which compare heparin requirements of conventional to daily dialysis. Objectives: To determine differences in heparin dose during conventional thrice‐weekly dialysis (CHD) compared to daily hemodialysis (DHD). Methods: All patients within the daily home hemodialysis at the Northwest Kidney Centers were evaluated for heparin dose both pre‐ and post initiation of daily hemodialysis. Patients on DHD received an initial bolus of heparin, without a continuous heparin drip, and supplemental heparin midway through the dialysis run as needed to maintain adequate activated clotting times (ACTs). CHD patients received a heparin bolus, followed by initiation of heparin drip as needed to maintain adequate ACTs. Results: Of the 1117 patients who dialyze at the NKC, 55% were Caucasian, 21% African‐American, 20% Asian/Pacific Islander, and 35% were of other ethnicity. The majority of patients were greater than 60 years (56%), while 36% ranged from 40–60 years and 13% ranged from 20–40 years. Male patients constituted 54% of patients. Diabetes was the primary cause of renal disease (36%), followed by hypertension (21%) and glomerular disease (18%). Of those patients in the home hemodialysis program (n = 45), 10 patients started daily home hemodialysis using the Aksys daily home hemodialysis system. Of those, the majority was male (100%), Caucasian (78.8%) with an average age of 46.7 ± 18 years. Glomerulonephritis was the primary cause of end‐stage renal disease (40%), while the percentages of other diseases were similar [Alport's syndrome (20%), hypertension (20%) and diabetes (10%)]. Compared to initial DHD heparin requirements (10,111 ± 2219 units), CHD heparin dose requirements (6833 ± 2715 units) were significantly lower (p = 0.045); however, total heparin needs were similar between groups (10,166 ± 4380 units vs. 10,778 ± 2959 units) (p = 0.324). Conclusion: Although patients initiating DHD have greater initial heparin requirements than when on CHD, total heparin doses remain similar to those required on conventional thrice‐weekly hemodialysis. Greater initial heparin doses required during short daily dialysis appear safe compared to those of conventional dialysis.  相似文献   
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Natural and artificial wetlands have the potential to reduce phosphorus (P) loads from dispersed agricultural runoff and from point sources in the Peel-Harvey catchment, Western Australia. Small experimental systems containing wetland plants and substrate have shown significant removal of P from inflowing water, the proportion of P removed being dependent on P concentration and flow rate of water through the system. The use of artificial wetlands to treat diffuse agricultural runoff is limited by the highly seasonal runoff typical of this Mediterranean climate, while use at point sources has so far been unsuccessful because compounds from the effluent clog the wetland filters. Treatment at point sources may well be feasible after further research.Natural wetlands in the catchment absorb P received in runoff from farmland and, in the absence of any outflow channels to the drainage system, confine this P within the boundaries of the wetland. Disturbance to wetlands may reduce their efficiency in absorbing nutrients and may release P stored in the vegetation and sediment to the water. The conservation of natural wetlands is recommended to maximise nutrient retention in the catchment.  相似文献   
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Abstract

System project failures are a well-known part of systems development; however, all the potential risks of planning and executing a project effort are not This article offers heuristic guidelines to help IS managers assess these inherent risk factors before initiating and while executing a project. Case examples illustrate how a particular risk factor can result in a failed systems development effort.  相似文献   
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The Cognitively-Based Rapid Assessment Methodology (C-RAM) system manages multiple-user interactions as users work with multiple information sources. Further, it allows users to view, exchange, organize, and combine the information available and it facilitates group decision-making. Three-member teams, randomly assigned in either the (a) view others’ whiteboards or (b) cannot view others’ whiteboards conditions, completed an intelligence analysis and mission planning task. Each team member was given access to a virtual whiteboard populated with decision cards (DCards) containing intelligence information constrained to a specific area of expertise. DCards can be assessed (rated) for decision impact and importance and team members have access to all DCards regardless of experimental condition. Team members who can view their teammates’ whiteboards during collaborative activities achieve significantly higher performance. When compared to teams unable to view others’ whiteboards, they move their own DCards less frequently, add fewer additional DCards to their own whiteboards, and rate others’ DCards less frequently. Additionally, rating one’s own DCards is the only process positively related team performance.  相似文献   
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In response to public concern, Health Canada recently conducted a review of amalgam safety and released a position statement entitled The Safety of Dental Amalgam. Essentially, the department has concluded that the levels of mercury absorbed by the body due to the release of mercury vapor from amalgam restorations, while detectable, do not approach those recognized to cause illness. It has therefore confirmed that amalgam restorations can be used safely in most patients, with some notable caveats. Despite Health Canada's position statement in support of amalgam, patient doubts about amalgam safety remain, including the tenuous hypothesized link between amalgam restorations and specific diseases. This article reviews the available studies of dentist mortality to identify possible links between mercury exposure and negative health effects. A lack of evidence to suggest a detrimental health outcome in dentists who are occupationally exposed to higher levels of mercury than their patients, and are known to have higher levels of mercury in their blood, provides an important reassurance concerning the safety of amalgam. The reviewed data indicates that the 10 leading causes of death in the United States and Canada are the same for both dentist and non dentist population groups, and that the percentage of deaths by the same cause are remarkably similar. By 1975, the year of the most recent U.S. study, the average age at death for white male dentists was about three years higher than for all adult white males. Although suicide standard mortality rates are known to be higher for dentists, suicide deaths have also been shown to be a factor in many other occupations, particularly those where there is easy access to drugs. Although updated actuarial data for dentist mortality are needed, the available data indicate no reduction in the life expectancy of practising dentists, nor any specific or disproportionate rates of disease associated with high mercury exposure. In fact, the available mortality studies are generally optimistic about the health of dentists, which should reassure patients about the safety of dental amalgam.  相似文献   
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