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471.
Several climate parameters affect the growth of organisms and, hence, their capacity to accumulate biomass. In the present research, we analyse the influence of two parameters, temperature and precipitation, on biomass accumulation on stone substrate, and propose a function to estimate it in temperate areas. The expression is subsequently used for the first time to evaluate the impact that climate change would have in biomass accumulation in Europe. The models on climate change predict an increase in temperature and precipitation in northern areas of Europe for the far future (2070–2099), which would lead to a higher accumulation of biomass. Otherwise, a significant reduction in precipitation is expected in southern areas of Europe, associated with a lower biomass accumulation in such areas.  相似文献   
472.
Work performed under the SPElling Error Detection COrrection Project (SPEEDCOP) supported by National Science Foundation (NSF) at Chemical Abstracts Service (CAS) to devise effective automatic methods of detecting and correcting misspellings in scholarly and scientific text is described. The investigation was applied to 50,000 word/misspelling pairs collected from six datasets (Chemical Industry Notes (CIN), Biological Abstracts (BA). Chemical Abstracts (CA), Americal Chemical Society primary journal keyboarding (ACS), Information Science Abstracts (ISA), and Distributed On-Line Editing (DOLE) (a CAS internal dataset especially suited to spelling error studies). The purpose of this study was to determine the utility of trigram analysis in the automatic detection and/or correction of misspellings. Computer programs were developed to collect data on trigram distribution in each dataset and to explore the potential of trigram analysis for detecting spelling errors, verifying correctly-spelled words, locating the error site within a misspelling, and distinguishing between the basic kinds of spelling errors. The results of the trigram analysis were largely independent of the dataset to which it was applied but trigram compositions varied with the dataset. The trigram analysis technique developed determined the error site within a misspelling accurately, but did not distinguish effectively between different error types or between valid words and misspellings. However, methods for increasing its accuracy are suggested.  相似文献   
473.
First, the theory of directed graphs (digraphs) was used to map the conceptual structure of the content, implicit in the instructional materials, in the area of electricity at college level. After this, the graphical representation of content structure, thus obtained, was compared with those obtained for the teacher's cognitive structure and the student's cognitive structure through a word association test and the multidimensional scaling technique. Research findings suggest mainly that the techniques used to assess content and cognitive structures might be useful tools for such a purpose.

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474.
Resumen

Este artículo explora un tema actual del diseño del curriculum. Después de hacer una definición de términos sobre el tema, se expone una propuesta sobre los distintos niveles de concreción del diseño del curriculum.  相似文献   
475.
476.
The European project Friendly-Heating (FH): comfortable to people and compatible with conservation of artworks preserved in churches addressed the problems caused by the continuous or intermittent heating of historic churches, which disturbs the microclimatic conditions to which the building and the artworks preserved inside have acclimatised. As thermal comfort and the preservation of artworks often conflict with each other, a balance between the two needs is necessary. The proposed heating strategy is to provide a small amount of heat directly to people in the pew area while leaving the conditions in the church, as a whole, undisturbed. This novel heating system is based on some low-temperature radiant emitters mounted in a pew to provide a desirable distribution of heat to the feet, legs and hands of people occupying it. Due to little heat dispersion, this novel system not only significantly reduces the risk of mechanical stress in wooden artworks and panel or canvas paintings, fresco soiling and cyclic dissolution-recrystallization of soluble salts in the masonry, but is energy-efficient. The detailed environmental monitoring was conducted in the church of Santa Maria Maddalena in Rocca Pietore, Italy over a 3-year period to verify the performance of the novel heating system in comparison to the warm-air system that was active earlier in the church. The methodology and results of this comprehensive and multidisciplinary study were included in three draft standards of the European Committee for Standardisation intended for use in the study and control of environments of cultural heritage objects.  相似文献   
477.
478.
In this study, we investigated the focus of visual attention in expert soccer players together with the effects of acute bouts of physical exercise on performance. In two discriminative reaction time experiments, which were performed both at rest and under submaximal physical workload, visual attention was cued by means of spatial cues of different size followed by compound stimuli with local and global target features. Soccer players were slower than non-athletes in reacting to local compared with global targets, but were faster in switching from local to global attending. Thus, soccer players appear to be less skilled in local attending, but better able than non-athletes to rapidly "zoom out" the focus of attention. Non-athletes generally showed faster performance under physical load, as expected according to the hypothesis of exercise-induced increases in arousal and/or activation and in resource allocation. In contrast, soccer players showed a more differentiated pattern of exercise-induced facilitation that selectively affects specific components of the attentional performance and is interpreted by referring to the role played by individual expertise and cognitive effort.  相似文献   
479.
This study aimed at determining the amount of Italian television coverage dedicated to men's and women's sport and the number of male and female viewers during the 2004 Summer Olympic Games. AUDITEL-AGB Nielsen Media Research Italia provided the TV airtime data for the sport events broadcast, which were classified into three categories: men-only, women-only, and mixed-gender. The viewer sample was divided by age and gender and included three audience parameters: mean audience, share, and appreciation index. The last item is calculated from the program duration, audience permanence, and the share related to programs broadcast by other Italian channels. In particular, the appreciation index was used to investigate the relationship between (a) the viewer's and sport participants' gender and (b) the effect of Italian participation and expectations for sport achievement. The data showed that Italian male athletes outnumbered their female counterparts. Women's sport was allotted significantly less airtime than men's sport, but this imbalance was not proportional to the gender difference in the overall athletes' participation in the Games. Although the female audience represented 45% of the total, a significantly higher male mean audience and share were found. On the other hand, the appreciation of men's and women's sport events was balanced after equating for differences in media coverage. Moreover sport achievement might have a positive effect on the trend toward equality of gender coverage, indicating that a global multisport event such as the Olympic Games is central to communicating a national image and identity independently of the athletes' gender.  相似文献   
480.
Nitroglycerin induces the so-called second window of protection (SWOP), which alleviates myocardial damage and stunning after ischaemia/reperfusion. To determine whether myocardial performance during exercise is improved in the second window of protection, we studied the haemodynamic responses of 12 trained and 11 sedentary individuals during a sequence of maximal tests on a cycle ergometer. A baseline test (basal test) was followed by a second effort performed during the second window of protection (exercise-SWOP test). Haemodynamics was also evaluated after pharmacologically induced SWOP 48 h after transdermal administration of 10 mg of nitroglycerin (pharmacologically induced SWOP test). The exercise-SWOP and pharmacologically induced SWOP tests were separated by a 1-week washout period. Endothelial-dependent vasodilatation after nitroglycerin pre-treatment was also assessed in five sedentary individuals to determine whether nitrate donors could affect vascular function. We found that nitroglycerin pre-treatment did not induce any improvement in haemodynamics in either trained or sedentary individuals, since maximum values of workload, heart rate, stroke volume, cardiac output, myocardial contractility, and double product were similar between the exercise-SWOP and pharmacologically induced SWOP tests in both groups. Furthermore, nitroglycerin pre-treatment did not alter flow-mediated dilation during pharmacologically induced SWOP. Although nitroglycerin pre-treatment alleviates post-ischaemic myocardial stunning, our results suggest that it does not affect the myocardial performance of healthy individuals during exercise performed in the second window of protection, independently of the training status of the individuals. Moreover, nitroglycerin pre-treatment does not ameliorate endothelial function.  相似文献   
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