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431.
Progress in the development of an intensive time-series design for use in classroom situations has raised several questions regarding the validity of the data obtained. One such question is related to the effect of frequency of testing upon the data. This study was designed to determine the presence of such an effect. Use of the design with eighth grade students studying a unit on crustal evolution indicated that the frequency of data collection did not adversely affect student attitudes toward the science class nor did it have any measurable effect upon class achievement data. The results of a previous study were also replicated, giving increased confidence in the validity of the data yielded by the intensive time-series design as used in these studies.  相似文献   
432.
Metacognition and Learning - The effectiveness of homework on improving student academic achievement depends on several factors; for example, feedback provided by the teacher (i.e. grading) and...  相似文献   
433.
Soothing pain-elicited distress in infants with swaddling and pacifiers   总被引:3,自引:0,他引:3  
The effectiveness of pacifiers and swaddling in reducing pain-induced distress was compared in 2-week-old infants who underwent heel-sticks and 2-month-old infants who received injections. Crying, state, and heart rate were measured on 32 infants at each age during baseline, the stress of heel-stick or injection, and during 3-min soothing intervention and postintervention periods. At 2 weeks, infants' HR levels and crying declined significantly more rapidly in the pacifier than in the swaddling condition. At 2 months, both conditions produced similar rates of decline in HR and crying. At both ages, infants in the pacifier group spent significantly more time in an alert state than did swaddled infants. Following termination of the intervention at both ages, HR and crying tended to rebound more in the pacifier than in the swaddling group. Swaddling and pacifiers thus reduce pain-elicited distress differently.  相似文献   
434.
A concept map is a node-link diagram in which each node represents a concept and each link identifies the relationship between the two concepts it connects. We investigated how using concept maps influences learning by synthesizing the results of 142 independent effect sizes (n = 11,814). A random-effects model meta-analysis revealed that learning with concept and knowledge maps produced a moderate, statistically significant effect (g = 0.58, p < 0.001). A moderator analysis revealed that creating concept maps (g = 0.72, p < 0.001) was associated with greater benefit relative to respective comparison conditions than studying concept maps (g = 0.43, p < 0.001). Additional moderator analyses indicated learning with concept maps was superior to other instructional comparison conditions, and was effective across science, technology, engineering, and math (STEM) and non-STEM knowledge domains. Further moderator analyses, as well as implications for theory and practice, are provided.  相似文献   
435.
The Erasmus Programme for higher education students is supposed to play an important socio-economic role within Europe. Erasmus student mobility flows have reached a relevant level of two million since 1987, boosted in recent years by the enlargement of the programme to eastern countries. Thereafter, it seems that flows have staggered. In this context, the article analyses the determinants of Erasmus student mobility establishing relevant hypotheses, which arise from the migration theory and gravity models. A panel data set of bilateral flows for all the participating countries has been used in order to test the factors influencing these student flows. Country size, cost of living, distance, educational background, university quality, the host country language and climate are all found to be significant determinants. Results also reveal that there are other determinants, like a country’s characteristics and time effects, which can affect mobility flows. Based on these findings, some general recommendations are put forward to enhance these flows.  相似文献   
436.

Introduction

Preanalytical control and monitoring continue to be an important issue for clinical laboratory professionals. The aim of the study was to evaluate a monitoring system of preanalytical errors regarding not suitable samples for analysis, based on different indicators; to compare such indicators in different phlebotomy centres; and finally to evaluate a single synthetic preanalytical indicator that may be included in the balanced scorecard management system (BSC).

Materials and methods

We collected individual and global preanalytical errors in haematology, coagulation, chemistry, and urine samples analysis. We also analyzed a synthetic indicator that represents the sum of all types of preanalytical errors, expressed in a sigma level. We studied the evolution of those indicators over time and compared indicator results by way of the comparison of proportions and Chi-square.

Results

There was a decrease in the number of errors along the years (P < 0.001). This pattern was confirmed in primary care patients, inpatients and outpatients. In blood samples, fewer errors occurred in outpatients, followed by inpatients.

Conclusion

We present a practical and effective methodology to monitor unsuitable sample preanalytical errors. The synthetic indicator results summarize overall preanalytical sample errors, and can be used as part of BSC management system.Key words: Preanalytical phase, errors in laboratory medicine, balanced scorecard, patient safety  相似文献   
437.
Entrepreneurs use resources and capacities to form core competencies. These are competitive advantages if they produce better company performance. Intellectual capital (IC) is a key resource for competitive advantage. This paper analyses the process through which entrepreneurs use this resource to obtain competitive advantages in regional SMEs. We show how entrepreneurs constitute three core competencies with IC and territory: internal knowledge management, relationship management and innovativeness. By partial least squares techniques we demonstrate that: (i) the two first factors influence innovativeness; (ii) this dynamic affects company performance. The study contributes to the analysis of the process of building core competencies by the entrepreneur from IC, in order to get better company performance.  相似文献   
438.
The purpose of this investigation was to analyse the concurrent validity and reliability of an iPhone app (called: My Jump) for measuring vertical jump performance. Twenty recreationally active healthy men (age: 22.1 ± 3.6 years) completed five maximal countermovement jumps, which were evaluated using a force platform (time in the air method) and a specially designed iPhone app. My jump was developed to calculate the jump height from flight time using the high-speed video recording facility on the iPhone 5 s. Jump heights of the 100 jumps measured, for both devices, were compared using the intraclass correlation coefficient, Pearson product moment correlation coefficient (r), Cronbach’s alpha (α), coefficient of variation and Bland–Altman plots. There was almost perfect agreement between the force platform and My Jump for the countermovement jump height (intraclass correlation coefficient = 0.997, P < 0.001; Bland–Altman bias = 1.1 ± 0.5 cm, P < 0.001). In comparison with the force platform, My Jump showed good validity for the CMJ height (= 0.995, P < 0.001). The results of the present study showed that CMJ height can be easily, accurately and reliably evaluated using a specially developed iPhone 5 s app.  相似文献   
439.
440.
Background: We aimed to evaluate the influence of the level of effort during four basic resistance exercises leading to muscular failure on intraocular pressure (IOP) and ocular perfusion (OPP), as well as the role of exercise type and sex. Methods: Twenty-five young adults (12 women) performed 10 repetitions against their 10-RM (repetition maximum) load in the squat, military press, biceps curl and calf raise exercises. IOP was measured before, during and after exercise, whereas OPP was indirectly assessed before and after each exercise. Results: There was a progressive IOP rise during exercise (p?η²?=?0.531), which was dependent on exercise type (p?=?0.020, η²?=?0.125). The squat exercise induced higher IOP increments in comparison to the other exercises (corrected p-values?p-values?=?0.012 and 0.002). OPP exhibited a significant reduction when leading to muscular failure (p?=?0.001, η²?=?0.364), being statistically significant for the squat and military press exercises (corrected p-values?=?0.037 and 0.047). No effect of sex was found for IOP and OPP (p?>?0.05). Conclusions: A single set of resistance training leading to muscular failure causes an instantaneous and progressive IOP rise in healthy young individuals. These IOP rises depend on exercise type (squat?>?military press?=?biceps curl?>?calf raise), but not on participant´s sex. OPP diminished as a consequence of performing resistance training exercise, being statistically significant for the squat and military press exercises. Future studies should include glaucoma patients aiming to corroborate the generalizability of our findings.  相似文献   
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