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331.
Using the famous Birthday problem, we present here a practical activity that allows students to perceive the basic reasoning behind simulation and explore its potential. Through a playful approach with probabilities, students are led along a path that illustrates difficulties with intuition and introduces them to theoretical results for sample proportions.  相似文献   
332.
This qualitative study seeks to create a better understanding of the work of school superintendents. This study was conducted using ethnographic techniques as a way to describe the practice of a Latino superintendent in a borderland community in south Texas. Guiding questions for this study were: What goes on in the workday life of a superintendent? and how does the superintendent enact his role as superintendent? Field study for this qualitative inquiry occurred over a period of seven months. Data for this study, including transgressive data, were collected primarily through participant observations, semi-structured ethnographic interviews, from artefacts and journal notes.  相似文献   
333.
Purpose: The talent identification and selection process in young male soccer players is mainly focused on anthropometrics and physical performance, but social factors are also considered in this process. The purpose of this study was to test the existence of the relative age effect and its possible influence on anthropometrics and physical performance and to analyze coaches’ efficacy expectations. Method: Data for 564 young male soccer players (Mage = 13.7 ± 1.5 years; Mweight = 53.7 ± 11.6 kg; Mheight = 160.2 ± 11.6 cm) included their birth quartile, maturity status, anthropometrics, a physical test battery, and coaches’ efficacy expectations. Results: Early-born players were overrepresented (< .05). Early-born players were not statistically taller, heavier, or better at physical performance (> .05) when maturation and chronological age were controlled as confounding factors. However, coaches expected more from early-born players (< .05), and the inferential analysis showed likely to very likely worthwhile differences between the coaches’ expectations for players born in the first quartile of the year and those born in the fourth quartile of the year. Conclusions: Anthropometrical and physical performance variables were not affected by birth quartile, and coaches’ efficacy expectations were related to the relative age effect.  相似文献   
334.
Two experiments with 79 monolingual German speaking children between 2.5 and 4.5 years showed a consistent developmental gap between children's memory/inference of what someone wanted and what someone wrongly said or thought. For instance, when John is still playing and mother says, "John should be going to bed," more than 70% answered correctly that mother wanted John to go to bed. However, when mother said, "John is going to bed," about 70% answered wrongly that she thought/said that he was still playing. Correct answers emerged with the mastery of the false-belief task. In German, want sentences (about something to happen) obligatorily take the same grammatical that complement as say or think sentences. Therefore, the observed gap constrains de Villier's (1995) linguistic determinism, which claims that acquisition of the necessary grammatical structures for talking about the mind drives children's ability to think about the mind.  相似文献   
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336.
We examined the effects of pre-exercise sodium bicarbonate (NaHCO3) ingestion on the slow component of oxygen uptake (VO2) kinetics in seven professional road cyclists during intense exercise. One hour after ingesting either a placebo or NaHCO3 (0.3 g x kg body mass(-1)), each cyclist (age, 25 +/- 2 years; VO2max, 74.7 +/- 5.9 ml x kg(-1) x min(-1); mean +/- s) performed two bouts of 6 min duration at an intensity of 90% VO2max interspersed by 8 min of active recovery. Gas exchange and blood data (pH, blood lactate concentration and [HCO3-]) were collected during the tests. In both bouts, the slow component of VO2 was defined as the difference between end-exercise VO2 and the VO2 at the end of the third minute. No significant difference was found in the slow component of VO2 between conditions in the first (NaHCO3, 210 +/- 69 ml; placebo, 239 +/- 105 ml) or second trial (NaHCO3, 123 +/- 88 ml; placebo, 197 +/- 101 ml). In conclusion, pre-exercise NaHCO3 ingestion did not significantly attenuate the VO2 slow component of professional road cyclists during high-intensity exercise.  相似文献   
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338.
The costs for deterioration and soiling of different materials due to air pollution are huge and the damage to culture targets endangers seriously the rich European cultural heritage. Within the sixth Framework Programme of the EU, the overall aim of the CULT-STRAT project has been to assess and predict the effects of different pollutants on materials and objects of cultural heritage in a multipollutant scenario and to identify indicators and thresholds levels of pollutants. In particular, the present paper reports one of the studies carried out in the CULT-STRAT project at city level and focused on the town of Madrid (Spain). Different maps are shown for the past, present and possible future scenarios: inventory of stock of cultural heritage for each selected material, concentration of selected pollutants (SO2, NO2, O3 and PM10), corrosion (cast bronze) and recession (Portland limestone), exceedance of tolerable degradation thresholds for each material and corrosion-cultural heritage overlapped maps. The model and the methodology developed could be useful if apply it to towns, regions or countries in order to quantify the percentage of Cultural Heritage at risk or to quantify the percentage of the area where corrosion/recession exceeds the established tolerable levels.  相似文献   
339.
Historic buildings are important for cultural history and provide a variety of habitats for animals and plants. Especially structural heterogeneity of wall surfaces is perceived to support biological diversity. Nevertheless, in traditional approaches goals of biodiversity preservation and monument restoration are perceived to interfere and to be mutually exclusive. As a consequence, priority is often given to constructional restoration accepting the loss of local populations and biodiversity. At walls of medieval castles, including an experimental restoration project where conventional and less intensive restoration techniques were applied, we relate species composition and richness to wall properties. Especially wall surface structure is quantified using a novel approach. The study focuses on lichens, mosses and vascular plants. Boosted regression tree analyses and non-metric multidimensional scaling techniques are applied to detect the influence of abiotic site conditions on biodiversity. We find species richness to be promoted by wall surface heterogeneity. However, species composition is more affected by restoration approaches than species richness. Lichen composition varies considerably while vascular plants and mosses are less affected by wall properties. We suggest strategies that are combining both societal targets, the preservation of historic monuments and of species diversity. Careful restoration is capable of supporting both, the maintenance of cultural heritage and of rare and unique anthropogenic habitats. Wall surface heterogeneity needs to be witnessed for both aspects as it affects both species composition as well as the effectiveness of cleaning methods.  相似文献   
340.
The present paper investigates the determinant factors in the organisation of a firm’s innovative activities. Set within a theoretical framework combining evolutionary theory and the resource-based view of the firm, the study includes an original proposal to characterise the innovative process and determines the extent to which a firm’s internal resources and factors explain the innovative process. By applying the econometric analyses techniques to a sample of 152 Spanish innovative companies, empirical findings confirm the existence of interesting relations between internal factors and the innovative process.  相似文献   
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