Are the new starting block facilities beneficial for backstroke start performance?     

Karla de Jesus  Kelly de Jesus  J. Arturo Abraldes  Alexandre Igor Araripe Medeiros  Ricardo J. Fernandes  João Paulo Vilas-Boas 《Journal of sports sciences》2016,34(9):871-877

We aimed to analyse the handgrip positioning and the wedge effects on the backstroke start performance and technique. Ten swimmers completed randomly eight 15 m backstroke starts (four with hands on highest horizontal and four on vertical handgrip) performed with and without wedge. One surface and one underwater camera recorded kinematic data. Standardised mean difference (SMD) and 95% confidence intervals (CI) were used. Handgrip positioning did not affect kinematics with and without wedge use. Handgrips horizontally positioned and feet over wedge displayed greater knee angular velocity than without it (SMD = ?0.82; 95% CI: ?1.56, ?0.08). Hands vertically positioned and feet over wedge presented greater take-off angle (SMD = ?0.81; 95% CI: ?1.55, ?0.07), centre of mass (CM) vertical positioning at first water contact (SMD = ?0.97; 95% CI: ?1.87, ?0.07) and CM vertical velocity at CM immersion (SMD = 1.03; 95% CI: 0.08, 1.98) when comparing without wedge use. Swimmers extended the hip previous to the knee and ankle joints, except for the variant with hands vertically positioned without wedge (SMD = 0.75; 95% CI: ?0.03, 1.53). Swimmers should preserve biomechanical advantages achieved during flight with variant with hands vertically positioned and wedge throughout entry and underwater phase.  相似文献   

Unveiling the Colours of Cellulose Nitrate Black and White Film-based Negatives in Colonial Photography     

Élia Roldão  A. Jorge Parola  Márcia Vilarigues  Bertrand Lavédrine 《文物保护研究》2020,65(2):118-126

ABSTRACT

Aiming at contributing to the preservation of black and white (B&W) film-based negatives held by Portuguese archives, four photographic collections from the first half of the twentieth century were selected for study. During the macro assessment of the collections the preservation condition and hues found in photographic negatives from the Elmano Cunha e Costa (ECC) were noticed, distinguishing this collection from the remaining ones. Additional attention was given considering that the ECC collection was formed in a colonial context in the 1930s, while the others were formed on the Portugal mainland. The ECC collection results from an ethnographic survey of Angolan tribes recorded with B&W film-based negatives. In this collection, sets of negatives with pink, lemon yellow, greenish, orange brownish, and red brownish hues were found. To identify the origin of such hues, the image layer was analysed by microscale energy-dispersive X-ray fluorescence (μ EDXRF) and scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX). Additionally, to assess the base decay and its effect on the formation of hues, the plastic supports were characterized by Fourier transform infrared microscopy (μ FTIR). To complement the assessment of the film-base decay, pH was measured by using combined microelectrodes. The identification of mercury, iodine, chromium, and iron by μ EDXRF allowed correlation of the hues found in the negatives with chemical corrective treatments performed to improve the image quality. SEM-EDX confirmed those results and proved that the elements found were in the photographic emulsion layer. The results obtained are relevant since the hues identified may now be used as markers to indicate the technical work performed on colonial photography. Additionally, the visual and molecular assessment of the negatives’ supports (good to fair condition) allow proposing that the original storage conditions may have had a beneficial contribution to their present condition.  相似文献   

Socio‐scientific controversies and students' conceptions about scientists     

Cecília Galvão 《International Journal of Science Education》2013,35(13):1621-1633

This article discusses the results of a mainly qualitative study into possible impacts of recent controversial socio‐scientific issues on a group of Portuguese secondary school students regarding their conceptions about scientists. The 86 participants: (1) answered a questionnaire with open‐ended questions; and (2) wrote a science fiction story involving a group of scientists working on a particular situation of her/his choice. Next, semi‐structured interviews were carried out to clarify and discuss the ideas embodied in the stories and mentioned in the questionnaire. All data underwent a process of content analysis. The socio‐scientific controversies recently discussed, and the way science and scientists are depicted in the media, seem to have produced some impact on students' conceptions about scientists. Based on the results obtained, some remarks and educational implications are discussed.  相似文献   

Early intervention in Portugal: family support and benefits     

Carina Sofia Correia Leite  Ana Paula Da Silva Pereira 《Support for Learning》2013,28(4):146-153

This study investigated the support and benefits of early intervention (EI) in families with children with special needs. Data were gathered through a written questionnaire, ‘Family Benefits Inventory’, completed by 126 families with children with special needs supported by EI teams, with ages from six months to six years in Portugal. The global results obtained in this study allowed us to conclude that families considered that they obtained benefit from EI and received support most of the time in the different dimensions of the questionnaire. Furthermore, support given by an EI professional had a positive influence on families' perceptions regarding the benefits of EI.  相似文献   

Does moderate-intensity continuous training result in greater total energy expenditure compared to high-intensity interval training?     

Leonardo Vidal Andreato  Braulio Henrique Magnani Branco  João Victor Esteves 《Journal of sports sciences》2019,37(11):1314-1315

Recently in the Journal of Sports Sciences, Schaun et al. published a study on the comparison of energy expenditure between high-intensity interval training and moderate continuous training performed in water. With this Letter to the Editor, we would like to comment on the methodological aspects that should be considered to analyze the results presented, as well as the conclusions.

Abbreviations: CONT, moderate-intensity continuous training; EPOC, excess post-exercise oxygen consumption; HIIT, high-intensity interval training; VO2max, maximal oxygen consumption.  相似文献   

Invest for the Long Term or Attend to Immediate Needs? Schools and the Employment of Less Educated Youths and Adults     

Inãki Santa Cruz  Gregori Siles  Natalija Vrecer 《European Journal of Education》2011,46(2):197-208

For the past 20 years, researchers worldwide have shared a consensus that tracking leads to failure in school. But educational systems continue to use this practice for many reasons. One argument used to support the practice is that students who enter the vocational track early in their careers tend to enter the labour market more quickly. Data show, however, that when these people are in their 40s, they become the most vulnerable to poverty, especially during periods of economic recession. In addition to moving towards more comprehensive educational systems as the best long-term way to improve the chances of all future adults, our research demonstrates that schools can play a key role in preventing and reversing the risk of unemployment and poverty of low educated youth. The INCLUD-ED project has analysed effective actions in eight European countries (Slovenia, United Kingdom, Italy, Austria, Romania, Belgium, Finland, and Spain) that respond to the educational needs of those who have experienced tracking. These effective alternatives are vocational programmes that include an academic-type of curriculum and allow students to move to higher education, as well as adult education programmes in schools which meet families' training needs, improving their opportunities in the labour market.  相似文献   

PUKHA: a new pedagogical experience     

A. Barbedo De Magalhães  M. Estima 《European Journal of Engineering Education》2007,32(6):711-719

Society needs responsible leaders and entrepreneurs. CDIO (conceive, design, implement and operate) is a framework for engineering education based on outcomes, more than on contents, that has been adopted by a growing number of engineering educational institutions for producing the next generation of engineering leaders. In order to support engineering students to become entrepreneurs and to bear other concerns than merely technical on today's rapid changing world, the authors believe the CDIO syllabus needs to be improved, and therefore propose a pre requisite to a useful CDIO perspective: IdEF, standing for Identify, Evaluate and Formulate real problems and needs. Based on this concept, this paper describes a new pedagogical project framework (PUKHA - to project, to undertake, to know how to achieve). Within PUKHA projects, more than 300 students have trained and checked their will, risk, responsibility, communication, leadership and entrepreneurship over the last three years.  相似文献   

Congenital learning,organisational performance and work-life balance culture     

Juan-Gabriel?Cegarra-NavarroEmail author  David?Cegarra-Leiva  María Eugenia?Sánchez-Vidal  Anthony?K.P. Wensley 《知识管理研究与实践》2015,13(1):105-114

A possible explanation for the numerous failures in the implementation and use of work-life balance (WLB) practices may relate to the fact that the majority of companies have introduced them without exploring the nature and extent of their founders’ or owners’ prior knowledge of WLB and WLB practices. This paper analyses the relationships between congenital learning and WLB culture and tries to identify whether WLB culture impacts on business performance through an empirical study of 229 small and medium-sized enterprises (SMEs) in the Spanish metal industry. Our findings show that in order to create positive attitudes toward WLB, managers need to create and support a learning process. These findings provide interesting insights into the drivers of organisational performance for SMEs that develop and support a WLB-supporting culture.  相似文献   

The conflict between science and religion: a discussion on the possibilities for settlement   总被引：1，自引：0，他引：1  

Eliane Brigida Morais Falcão 《Cultural Studies of Science Education》2010,5(1):47-54

In his article Skepticism, truth as coherence, and construtivist epistemology: grounds for resolving the discord between science and religion?, John Staver identifies what he considers to be the source of the conflicts between science and religion: the establishment of the relationship between truth and knowledge, from the perspective of those who see a correspondence between reality and knowledge, assumed in the realm of both contending fields. In the present work, although agreeing with the general principles of constructivism, I discuss Staver’s option of viewing truth as coherence and his proposal of renouncing the objective of knowing reality from both fields’ perspective. Three aspects of Staver’s article are commented and discussed here: the one referring to views of reality or of nature as shared by scientists; the one concerning the different forms of religious beliefs among scientists; and the one accounting for the impossibility, from the standpoint of constructivism, of determining limits to the objectives of science and religion. Also emphasized in this discussion is the importance of combining theoretical and methodological approaches in tune with the complexity of the theme under discussion, accounting for the need to preserve the freedom of thinking and of doing research.  相似文献   

High-throughput study of alpha-synuclein expression in yeast using microfluidics for control of local cellular microenvironment   总被引：1，自引：0，他引：1  

Rosa P  Tenreiro S  Chu V  Outeiro TF  Conde JP 《Biomicrofluidics》2012,6(1):14109-141099

Microfluidics is an emerging technology which allows the miniaturization, integration, and automation of fluid handling processes. Microfluidic systems offer low sample consumption, significantly reduced processing time, and the prospect of massive parallelization. A microfluidic platform was developed for the control of the soluble cellular microenvironment of Saccharomyces cerevisiae cells, which enabled high-throughput monitoring of the controlled expression of alpha-synuclein (aSyn), a protein involved in Parkinson's disease. Y-shaped structures were fabricated using particle desorption mass spectrometry-based soft-lithography techniques to generate biomolecular gradients along a microchannel. Cell traps integrated along the microchannel allowed the positioning and monitoring of cells in precise locations, where different, well-controlled chemical environments were established. S. cerevisiae cells genetically engineered to encode the fusion protein aSyn-GFP (green fluorescent protein) under the control of GAL1, a galactose inducible promoter, were loaded in the microfluidic structure. A galactose concentration gradient was established in the channel and a time-dependent aSyn-GFP expression was obtained as a function of the positioning of cells along the galactose gradient. Our results demonstrate the applicability of this microfluidic platform to the spatiotemporal control of cellular microenvironment and open a range of possibilities for the study of cellular processes based on single-cell analysis.  相似文献