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171.
Luana L. Cabral Fábio Y. Nakamura Joice M. F. Stefanello Luiz C. V. Pessoa Bruno P. C. Smirmaul Gleber Pereira 《Measurement in physical education and exercise science》2020,24(2):103-114
ABSTRACTThe aims of this study were to perform the cross-cultural adaptation of the Borg Rating of Perceived Exertion (RPE) 6–20 Scale to Brazilian Portuguese language and to start testing its validity and reliability. After performing the cross-cultural adaptation of the Scale, concurrent and discriminative validity, and reliability were determined on a treadmill in young (18–30 years) and older adult women (60–75 years). Considering young and older adult women, RPE presented high and moderate positive correlation with heart rate and high and low positive correlation with oxygen consumption, respectively. Older adult women presented RPE (11 ± 2) significantly higher than young ones (8 ± 1) exercising at the same absolute intensity. Intraclass coefficient correlation was excellent for RPE to young and older adult women. The Scale presented concurrent validity only to young adult women, whereas it presented discriminative validity between such groups of women. Moreover, the scale is reliable to young and older adult women. 相似文献
172.
Pedro L. Valenzuela Michael McGuigan Guillermo Sánchez-Martínez Elaia Torrontegi Javier Vázquez-Carrión Zigor Montalvo 《Journal of sports sciences》2020,38(19):2273-2278
ABSTRACT The present study aimed to provide reference values for lower-limb muscle power assessed during the incremental jump squat (JS) test in elite athletes (i.e., professional athletes competing at international level). We pooled data from all JS tests performed by elite athletes of different sports in two high-performance centres between 2015 and 2019, and computed reference values (i.e., terciles) for mean power (MP), mean propulsive power (MPP), and peak power (PP). Reference values were obtained from 684 elite athletes (458 male and 226 female) of 16 different sports (boxing, judo, karate, fencing, taekwondo, wrestling, basketball, soccer, futsal, handball, rugby union, badminton, tennis, long distance running, triathlon, and sprinting). Significant differences (p < 0.001) were found between male and female athletes for MP (7.47 ± 1.93 and 6.15 ± 1.68 W·Kg?1, respectively), MPP (10.50 ± 2.75 and 8.63 ± 2.43 W·Kg?1), and PP (23.64 ± 6.12 and 19.35 ± 5.49 W·Kg?1). However, the velocity at which these power measures was attained seemed to be independent of sex (~0.95, 1.00 and 2.00 m·s?1 for mean, mean propulsive, and peak velocity, respectively) and homogeneous across different sport disciplines (coefficient of variation <10%). These data can be used to classify athletes’ power capabilities, and the optimum velocity ranges provided here could be useful for training purposes. 相似文献
173.
174.
Arco-Tirado José L. Fernández-Balboa Juan-Miguel 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》2003,49(6):585-600
Over the past two decades, the Spanish educational system has undergone various legal reforms. However, judging by the low educational performance of Spanish students as reported by the OECD for the year 2001, it seems that additional reforms are necessary. Several factors may account for the failure of previous reforms to attain the desired results. These include: (a) educators' low expectations that further reforms will succeed, (b) lack of financial resources, (c) institutional lack of commitment to implement the structural and administrative changes called for and (d) the adoption of questionable theoretical models for making appropriate structural, curricular and educational decisions. This essay presents some suggestions for implementing a reform program that would bring about substantial changes in these areas. 相似文献
175.
Vanessa Otero Joana V. Pinto Leslie Carlyle Márcia Vilarigues Marine Cotte 《文物保护研究》2017,62(3):123-149
The Winsor & NewtonTM (W&N) nineteenth century archive database includes digitised images of hand-written instructions and workshop notes for the manufacture of their artists’ materials. For the first time, all 183 production records for yellow lead chromate pigments were studied and evaluated. They revealed that W&N produced essentially three pigment types: lemon/pale based on mixed crystals of lead chromate and lead sulphate [Pb(Cr,S)O4]; middle on pure monoclinic lead chromate [PbCrO4]; and deep that contains the latter admixed with basic lead chromate [Pb2CrO5]; accounting for 53, 22, and 21% of the production, respectively. Production records for primrose (4%) were also included since the formulation results in mixed crystals with a high percentage of lead sulphate, which, according to the literature, leaves it more prone to degradation. Each pigment type is characterised by only one or two main synthetic pathways; process variations reveal a systematic and thorough search for a high-quality durable product. A comparison of the chemical composition of pigment reconstructions with early W&N oil paint tubes showed that their records entitled ‘pale’ and ‘lemon’ correlated with the pigment in their tube labelled chrome yellow and, ‘middle’ and ‘deep’ with the label chrome deep. Lemon and middle pigment formulations were made into oil paints to assess their relative photo-stability. The degradation process was followed by colorimetry and was studied by synchrotron radiation-based techniques. Based on the X-ray absorption spectroscopy data, the possibility for creating a stability index for chrome yellows is discussed. 相似文献
176.
To assess the relevance of the Public Library System in the political agenda, programs presented by the Political Parties competing in Regional and Local elections in the Spanish Region of Castilla-La Mancha were analyzed and the proposals about these library institutions were identified.
All Regional programs were collected and also an ample sample from the Municipalities for the 2007 and 2015 elections, trying to find the differences influenced by the impact of the financial crisis and recession on the public-library policies.
The conclusion arrived at was that, although the Public Libraries may be reasonably present in the studied programs, there is a low awareness by the Political Parties of the main problems. 相似文献
177.
Lorenzo G. Lledó A. Pérez-Vázquez E. Lorenzo-Lledó A. 《Education and Information Technologies》2021,26(4):4111-4126
Education and Information Technologies - During the last two decades, the use of Information and Communication Technologies (ICT) has opened new paths in the intervention of people with Autism... 相似文献
178.
Evdokimova Olga L. Alves Carla S. Krsmanović Whiffen Radenka M. Ortega Zaida Tomás Helena Rodrigues João 《Journal of Zhejiang University. Science. B》2021,22(6):450-461
In this study, the fibers of invasive species Agave americana L. and Ricinus communis L. were successfully used for the first time as new sources to produce cytocompatible and highly crystalline cellulose nanofibers. Cellulose nanofibers were obtained by two methods, based on either alkaline or acid hydrolysis. The morphology, chemical composition, and crystallinity of the obtained materials were characterized by scanning electron microscopy(SEM) together with energy-dispersive X-ray spectroscopy(EDX), dynamic light scattering(DLS), X-ray diffraction(XRD), and Fourier transform infrared(FTIR)spectroscopy. The crystallinity indexes(CIs) of the cellulose nanofibers extracted from A. americana and R. communis were very high(94.1% and 92.7%, respectively). Biological studies evaluating the cytotoxic effects of the prepared cellulose nanofibers on human embryonic kidney 293 T(HEK293 T) cells were also performed. The nanofibers obtained using the two different extraction methods were all shown to be cytocompatible in the concentration range assayed(i.e., 0-500 μg/mL). Our results showed that the nanocellulose extracted from A. americana and R. communis fibers has high potential as a new renewable green source of highly crystalline cellulose-based cytocompatible nanomaterials for biomedical applications. 相似文献
179.
Marisa Raquel De Giusti Ariel Jorge Lira Gonzalo Luján Villarreal 《European Journal of Engineering Education》2008,33(5-6):587-596
Simulation is the process of executing a model that describes a system with enough detail; this model has its entities, an internal state, some input and output variables and a list of processes bound to these variables. Teaching a simulation language such as general purpose simulation system (GPSS) is always a challenge, because of the way it executes the models and the abstraction level it can achieve, very different compared with most well-known programming languages. This article presents an open source simulation framework that implements a subset of entities of GPSS, which could help students to improve the understanding of this language. This tool also stores all entities of simulations in every single simulation time, which is very useful for debugging simulations, but also for getting a detailed history of all entities in the simulations, knowing exactly how they have behaved in every simulation time. 相似文献
180.