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891.
This paper explores varying configurations of knowledge in organisations. A multi-dimensional framework of distinctive forms of knowledge is used to highlight different patterns of organisational knowledge, demonstrating their heterogeneity and variability – over time, in terms of depth of expertise, and their distribution within and between organisations. Common knowledge that is shared across an organisation accounts for only a small proportion of organisational knowledge, indicating that strategies to exploit this resource for competitive advantage will be constrained unless mechanisms are developed that enable access to and transfer of knowledge that is not yet shared or common.  相似文献   
892.

Introduction:

Today, the pneumatic tube transport system (PTS) is used frequently because of its advantages related to timing and speed. However, the impact of various types of PTS on blood components is unknown. The aim of this study was to examine the influence of PTS on the quality of routine blood cell counts, erythrocyte sedimentation, and certain blood coagulation tests.

Materials and methods:

Paired blood samples were obtained from each of 45 human volunteers and evaluated by blood cell count, erythrocyte sedimentation, and several coagulation tests, including prothrombin time (PT) and activated partial thromboplastin time (aPTT). Blood samples were divided into 2 groups: Samples from group 1 were transported to the laboratory via the PTS, and samples from group 2 were transported to the laboratory manually. Both groups were evaluated immediately by the tests listed above.

Results:

The blood sample test results from groups 1 and 2 were evaluated and compared. No statistically significant differences were observed (P = 0.069–0.977).

Conclusion:

The PTS yielded no observable effects on blood cell counts, erythrocyte sedimentation, or PT and aPTT test results. We concluded that the PTS can be used to transport blood samples and yield reliable results for blood cell counts, erythrocyte sedimentation, and several coagulation tests.  相似文献   
893.
Phlebotomy is one of the most complex medical procedures in the diagnosis, management and treatment of patients in healthcare. Since laboratory test results are the basis for a large proportion (60–80%) of medical decisions, any error in the phlebotomy process could have serious consequences. In order to minimize the possibility of errors, phlebotomy procedures should be standardised, well-documented and written instructions should be available at every workstation. Croatia is one of the few European countries that have national guidelines for phlebotomy, besides the universally used CLSI (Clinical Laboratory Standards Institute) H3-A6 Procedures for the Collection of Diagnostic Blood Specimens by Venipuncture; approved Standard-Sixth Edition (CLSI, 2007) and WHO (World Health Organization) guidelines on drawing blood: best practices in phlebotomy (WHO, 2010). However, the growing body of evidence in importance of preanalytical phase management resulted in a need for evidence based revision and expansion of existing recommendations.The Croatian Society for Medical Biochemistry and Laboratory Medicine, Working Group for the Preanalytical Phase issued this recommendation. This document is based on the CLSI guideline H3-A6, with significant differences and additional information.  相似文献   
894.
An increasing prevalence of gestational diabetes has become a very challenging task in prenatal care worldwide. International Association of Diabetes and Pregnancy Study Groups (IADPSG) has recently issued recommendations on the diagnosis and classification of hyperglycaemia in pregnancy. These recommendations, the first to provide harmonised, evidence-based criteria for the diagnosis and classification of diabetes in pregnancy, are currently being discussed and accepted worldwide by the relevant authorities. As the acceptance of the proposed criteria has major implications for both clinical and laboratory settings, a concerted action towards necessary changes in practice has to be carefully planned and adjusted to national health-care specificities.IADPSG criteria have been strongly advocated by the Croatian Perinatology Society, resulting in a new strategy for the detection and diagnosis of hyperglycaemic disorders in pregnancy.To address the respective laboratory requirements, in April 2012, the Croatian Chamber of Medical Biochemists appointed a Working Group to provide a standardised procedure for the diagnosis of gestational diabetes, applicable to all laboratories involved in prenatal care, in both primary and specialised health-care facilities.In this paper we discuss key laboratory-related issues regarding succesful implementation of the IADPSG criteria in Croatia.  相似文献   
895.
Abstract

Research on the benefits of distributed practice for the acquisition and retention of motor skills has a long history. The majority of this research has involved skill acquisition of continuous tasks. However, there is some evidence to suggest that distribution of practice effects are quite different for discrete tasks than for continuous tasks. In the present study, we used a single task, formed discrete and continuous versions of the task, and examined how acquisition and retention were affected by the length of inter-trial interval. The basic task was a movement timing task that involved either one timing estimate per trial (the “discrete” version) or twenty successive estimates per trial (the “continuous” version). Separate groups of subjects learned one version of the task under either distributed (25 s inter-trial intervals) or massed (0.5 s inter-trial intervals) practice conditions. Both massed and distributed retention trials were performed on the same version of the task according to a double transfer design. The results confirmed the apparent disparity: Acquisition and retention were facilitated by distributed practice on the continuous task, but by massed practice on the discrete task. These results were discussed in terms of the role of the inter-trial interval in discrete and continuous tasks.  相似文献   
896.
Abstract

An experimental design was employed to assess the effectiveness of a relapse prevention program, a reinforcement program, and an exercise-only control group in increasing exercise program adherence and short-term maintenance in 120 previously sedentary female university employees. The subjects participated in an 18-week exercise program composed of stretching, calisthenics, and aerobic dance. Attendance during the first half of the program was significantly higher for subjects in the relapse prevention group than for those in the control group. A nonsignificant trend in this direction emerged during the second half of the program and at 2-month follow-up. For all treatment groups, attrition (attendance at less than two thirds of the exercise sessions) was substantial, averaging 72% at the end of the 18-week program. These findings indicate that relapse prevention and reinforcement programs may not assist previously sedentary females in long-term adherence to an exercise program.  相似文献   
897.
898.
Abstract

The purpose of this study was to determine the minimum and maximum velocity of the tennis ball for selected heights of contact and angles of projection and wall impact points during the tennis serve. By use of a ballistics formula, a number of variables which determine the trajectory of the tennis ball were programed for the computer. Tables were tabulated and are available for all data gathered. Angles of projection from the horizontal were selected to range from ?5° to 15° in increments of 1°. Velocity of the serve ranged from a low of 30 ft. per second to a high of 176 ft. per second. Finally, the height of the contact point ranged from a low of 6.0 ft. to a high of 9.0 ft. in increments of .5 ft. Height of the ball when crossing the net (impact point on the practice court) ranged from a low of 3.01 ft. to a high of 8.47 ft. The minimum height at crossing was achieved at 6.5 ft. service height, a ?3° angle of projection and time from baseline of .30 sec. This is a relatively high velocity serve. In contrast, the maximum height over the net of 8.47 ft. was achieved at an 8.5 ft. service height, a 15° angle of projection, and time of .79 sec. to point of impact. These data indicate that at higher service heights and slower velocities, a ball can hit the impact area as much as 8.47 ft. from the floor, 4.47 ft. above the net and still remain in the service court.  相似文献   
899.
Abstract

Nine males cycled at 53% (s = 2) of their peak oxygen uptake ([Vdot]O2peak) for 90 min (dry bulb temperature: 25.4°C, s = 0.2; relative humidity: 61%, s = 3). One litre of flavoured water at 10 (cold), 37 (warm) or 50°C (hot) was ingested 30 – 40 min into exercise. Immediately after the 90 min of exercise, participants cycled at 95%[Vdot]O2peak to exhaustion to assess exercise capacity. Rectal and mean skin temperatures and heart rate were recorded. The gradient of rise in rectal temperature was influenced (P < 0.01) by drink temperature. Mean skin temperature was highest in the hot trial (cold trial: 34.2°C, s = 0.5; warm trial: 34.4°C, s = 0.5; hot trial: 34.7°C, s = 0.6; P < 0.01). Significant differences were observed in heart rate (cold trial: 132 beats · min?1, s = 13; warm trial: 134 beats · min?1, s = 12; hot trial: 139 beats · min?1, s = 13; P < 0.05). Exercise capacity was similar between trials (cold trial: 234 s, s = 69; warm trial: 214 s, s = 52; hot trial: 203 s, s = 53; P = 0.562). The heat load and debt induced via drinking resulted in appropriate thermoregulatory reflexes during exercise leading to an observed heat content difference of only 33 kJ instead of the predicted 167 kJ between the cold and hot trials. These results suggest that there may be a role for drink temperature in influencing thermoregulation during exercise.  相似文献   
900.
Abstract

In spite of the increased acceptance of artificial turf in football, few studies have investigated if matches are altered by the type of surface used and no research has compared physiological responses to football activity on artificial and natural surfaces. In the present study, participants performed a football match simulation on high-quality artificial and natural surfaces. Neither mean heart rate (171 ± 9 beats · min?1 vs. 171 ± 9 beats · min?1; P > 0.05) nor blood lactate (4.8 ± 1.6 mM vs. 5.3 ± 1.8 mM; P > 0.05) differed between the artificial and natural surface, respectively. Measures of sprint, jumping and agility performance declined through the match simulation but surface type did not affect the decrease in performance. For example, the fatigue index of repeated sprints did not differ (P > 0.05) between the artificial, (6.9 ± 2.1%) and natural surface (7.4 ± 2.4%). The ability to turn after sprinting was affected by surface type but this difference was dependent on the type of turn. Although there were small differences in the ability to perform certain movements between artificial and natural surfaces, the results suggest that fatigue and physiological responses to football activity do not differ markedly between surface-type using the high-quality pitches of the present study.  相似文献   
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