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51.
This article analyses the manner in which the physical and sexual energy of the white, native South American and black populations was represented in reading books for elementary school children in Spain and Colombia between 1900 and 1960. Ninety reading books from representative authors were examined. It was found that the ideal of extraordinary physical vigour attributed to the white male was decisive in justifying Spanish imperialism, the superiority of the male in the patriarchal family and the intervention of authorities in administering people’s bodies. In the case of Spanish texts, the might attributed to the white race was shown as having a motive of pride, whereas in the Colombian case, the mixture with Native Americans and blacks tended to be used as an explanation for the ‘weakness’ of Colombians. Evidence is also found of the way in which education was implicitly conceived as a process of cultural ‘whitening’.  相似文献   
52.
In this work we exploit a long-in-time panel of Spanish manufacturing firms observed during the period 1990–2012 to examine the long-run contribution of innovation persistence to sales growth and market share dynamics. We examine two main research questions. First, do persistent innovators grow more than other firms? Second, do persistent innovators show more persistent growth patterns over time compared to other firms? We find negative answers to both questions: firms that persistently innovate over the first decade, do not grow more and do not display more persistent growth dynamics in the succeeding years, regardless of whether innovation persistence is defined in terms of R&D, patenting activity, or product or process innovation. These findings lend support to luck and random theories of firm growth, in turn challenging innovation persistence theories commonly suggesting that persistent innovators enjoy large and sustained comparative advantages.  相似文献   
53.
We tested the hypothesis that critical intensity in cycling can be determined from a single delta blood lactate in the third minute of a submaximal cycle ergometer trial. Fourteen healthy young men performed four to six constant-power-output trials on a cycle ergometer to the limit of tolerance. Critical intensity was calculated via a linear model and subsequently validated. Lactate was measured at baseline and at 3 min from exercise onset. Delta lactate was the difference between these measures. Based on individual trials, we obtained the delta lactate–% validated critical intensity relationship and thereafter an estimate of critical intensity was computed. Validated and estimated critical intensity were compared by effects sizes, paired-sample t-test and Bland–Altman analysis. Delta lactate was a linear function of the intensity of exercise, expressed as % validated critical intensity (R2 = 0.89). Estimated critical intensity was not different from (= 0.03, P = 0.98) and highly correlated with (R2 = 0.88) validated critical intensity. The bias between measures was 0.03 W (≠0) with a precision of 7 W. The results suggest that critical intensity in cycling can be accurately and precisely determined from delta lactate during a sub-maximal trial and so provides a practical and valid alternative to direct determination.  相似文献   
54.
ABSTRACT

We aimed to evaluate the changes in double poling (DP) kinematics due to a long-distance cross-country skiing race in athletes with different performance levels. A total of 100 cross-country skiers, belonging to 10 different performance groups, were filmed on flat terrain 7 and 55 km after the start line, during a 58-km classical race. Cycle velocity, frequency and length decreased from the best to the lower-ranked group, while duty cycle increased (all P <.001). Between track sections, cycle velocity and length decreased, duty cycles increased (all P <.001) while frequency was unaltered (P =.782). Group*section interactions resulted for cycle velocity (P =.005). Considering all the participants together, % change in cycle velocity between sections correlated with % change in length and duty cycle (all P <.001). Thus i) skiers in better groups showed longer and more frequent cycles as well as shorter duty cycles than skiers in slower groups; ii) throughout the race all the groups maintained the same cycle frequency while decreasing cycle velocity and length; iii) better groups showed a lower reduction in cycle velocity. Individually, a low reduction in cycle velocity during the race related to the capacity to maintain long cycles and short duty cycles.  相似文献   
55.
Abstract

Subject indexing and classification of law resources is a complex issue due to several factors: specialized meanings of legal terms, meanings across different branches of law, terms in legal systems from diverse countries, and terms in different languages. These issues led to the development of a classification and subject indexing system which will help answer the major challenges of indexing and classifying law resources in the Research Institute Library at the National Autonomous University of Mexico. Adopting its own classification required interdisciplinary work between law and information organization specialists, constant updating by legal specialists and others beyond the Legal Research Institute; and the sharing of this classification system with other institutions. Now, this classification system is used by important institutions that specialize in law, such as the network of Libraries of the Supreme Court of Justice of the Nation of Mexico. The purpose of this article is to show why and how this law classification and subject system was developed and is continuously being updated by libarians and law scholars in order for it to meet their specific needs.  相似文献   
56.
ABSTRACT

There is a strong relationship between low physical activity level and cardiovascular diseases (CVD). The popularity of football may be used to promote physical activity and previous evidence has shown it is effective to decrease the risk of CVD. However, the energy expenditure (EE) of recreational football is not well known but it is crucial to develop preventive health programmes.

Fifteen sedentary middle-aged male participants were involved (mean ± SDs; age 43.9 ± 3.1 years, weight 83.0 ± 13.6 kg, height 174.9 ± 6.8 cm). EE was estimated from the heart rate (HR)-VO2 relation during 1-h 5-a-side matches (futsal). Participants covered 3412 ± 381 m in 52 ± 2 min, at an average HR of 85 ± 2% of maximum HR. Estimated EE during a recreational futsal match was 634 ± 92 kcal. One futsal recreational match corresponds to about 50% of American College of Sport Medicine recommended physical activity quantity per week. Based on this estimation: once, twice and 3 sessions per week are equivalent to 50% (634 kcal), 100% (1268 kcal) and 150% (1902 kcal), respectively, of EE suggested in international guidelines. This EE estimation may have important implications for designing recreational football training protocols in health programmes and dose response studies.  相似文献   
57.
Each of four pigeons was exposed to a single random-ratio schedule of reinforcement in which the probability of reinforcement for a peck on either of two keys was 1/25. Reinforcer amounts were determined by an iterated prisoner’s dilemma (IPD) matrix in which the “other player” (a computer) playedtit-for-tat. One key served as thecooperation(C) key; the other served as thedefection(D) key. If a peck was scheduled to be reinforced and the D-key was pecked, the immediate reinforcer of that peck was always higher than it would have been had the C-key been pecked. However, if the C-key was pecked and thefollowing peck was scheduled to be reinforced, reinforcement amount for pecks on either key were higher than they would have been if the previous peck had been on the D-key. Although immediate reinforcement was always higher for D-pecks, the overall reinforcement rate increased linearly with the proportion of C-pecks. C-pecks thus constituted a form of self-control. All the pigeons initially defected with this procedure. However, when feedback signals were introduced that indicated which key had last been pecked,cooperation (relative rate of C-pecks)—hence, self-control—increased for all the pigeons.  相似文献   
58.
Across the United States, the ‘no-excuses’ charter school movement featuring strict discipline policies and rigorous academic standards has gained popularity among schools serving poor and working-class students of color. In this article, we examine how Black and Latinx parents of students with disabilities1 negotiated and experienced these charter school practices of rigor, which disciplined, managed, and regulated students’ social differences. Drawing from a yearlong qualitative research study, we examine interviews with Black and Latinx parents who experienced conflict with charter schools and the school lawyers, along with school artifacts we gathered such as parent handbooks and website information. We found parents experienced what we refer to as the ‘irony of rigor:’ the contradictory double-movement through which students of color with disabilities desired inclusion into ‘rigorous’ charter schools which then excluded them using ‘rigor’ as a central feature of student pushout practices. We present the irony of rigor in three interrelated acts: Act I: the lure of rigor (i.e. what drew parents to charter schools); Act II: the body meets rigor (i.e. how schools disciplined and managed student differences); and Act III: the consequences of rigor (i.e., what happened to students and parents while and after experiencing rigorous practices). We contextualize the irony of rigor within the relationship between disability, race, and neoliberalism.  相似文献   
59.
60.
This work reviews information retrieval systems developed at ITC-irst which were evaluated through several tracks of CLEF, during the last three years. The presentation tries to follow the progress made over time in developing new statistical models first for monolingual information retrieval, then for cross-language information retrieval. Besides describing the underlying theory, performance of monolingual and bilingual information retrieval models are reported, respectively, on Italian monolingual tracks and Italian-English bilingual tracks of CLEF. Monolingual systems by ITC-irst performed consistently well in all the official evaluations, while the bilingual system ranked in CLEF 2002 just behind competitors using commercial machine translation engines. However, by experimentally comparing our statistical topic translation model against a state-of-the-art commercial system, no statistically significant difference in retrieval performance could be measured on a larger set of queries.  相似文献   
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