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721.
Over the past 15?years, many state governments in Mexico have initiated local programs to introduce English at the primary school level. In 2009, the Mexican Ministry of Education formalized the Programa Nacional de Inglés en Educación Básica (PNIEB) as part of the national curriculum, based on the argument that increasing the number of English speakers in Mexico is necessary for the country to be globally competitive and to follow the trend in other developing economies of augmenting English instruction in public education. This paper focuses on the implementation of PNIEB and the state programs that preceded it. The authors document the practices and challenges associated with the program based on data collected from interviews with the main stakeholders involved (students and parents, teachers, school principals, and program coordinators) and from classroom observations. The total data-set consisted of over 200 interviews and classroom observations spread over several years from 2008 to 2012. Several challenges are described, including the development of materials, the role of English in relation to other subject areas, and the training of teachers who often speak English but have uneven formal preparation. The status of the teachers, both as second-class citizens within the schools and the instability and irregularities with their contracts, was identified as the most significant challenge to the successful implementation of the programs.  相似文献   
722.
The use of new technologies in higher education has surprisingly emphasized students’ tendency to adopt a passive behavior in class. Participation and interaction of students are essential to improve academic results. This paper describes an educational experiment aimed at the promotion of students’ autonomous learning by requiring them to generate test type questions related to the contents of the course. The main idea is to make the student feel part of the evaluation process by including students’ questions in the evaluation exams. A set of applications running on our university online learning environment has been developed in order to provide both students and teachers with the necessary tools for a good interaction between them. Questions uploaded by students are visible to every enrolled student as well as to each involved teacher. In this way, we enhance critical analysis skills, by solving and finding possible mistakes in the questions sent by their fellows. The experiment was applied over 769 students from 12 different courses. Results show that the students who have actively participated in the experiment have obtained better academic performance.  相似文献   
723.
In most real-life bilateral teleoperators the available physical parameters are uncertain and the communications exhibit variable time-delays. In order to confront these situations and only assuming that a bound of the time-delays is known, the present work reports an adaptive controller which ensures asymptotic convergence of both position errors and velocities to zero, provided that a sufficient condition on the control gains is met. Compared to previous related works that only treated constant time-delays, the stability analysis does not rely on the cascade interconnection structure of the local and remote nonlinear dynamics and the linear interconnection map. Instead, the paper employs a different Lyapunov candidate function that incorporates a strictly positive term, the local and remote position error. Some simulations, in free space and interacting with a rigid wall, and experiments, using two nonlinear manipulators, illustrate the performance of the proposed control scheme in the presence of uncertain parameters and variable time-delays.  相似文献   
724.

Introduction

Technological innovation requires the laboratories to ensure that modifications or incorporations of new techniques do not alter the quality of their results. In an ISO 15189 accredited laboratory, flexible scope accreditation facilitates the inclusion of these changes prior to accreditation body evaluation. A strategy to perform the validation of a biochemistry analyzer in an accredited laboratory having a flexible scope is shown.

Materials and methods:

A validation procedure including the evaluation of imprecision and bias of two Dimension Vista analysers 1500 was conducted. Comparability of patient results between one of them and the lately replaced Dimension RxL Max was evaluated. All studies followed the respective Clinical and Laboratory Standards Institute (CLSI) protocols. 30 chemistry assays were studied. Coefficients of variation, percent bias and total error were calculated for all tests and biological variation was considered as acceptance criteria. Quality control material and patient samples were used as test materials. Interchangeability of the results was established by processing forty patients’ samples in both devices.

Results:

27 of the 30 studied parameters met allowable performance criteria. Sodium, chloride and magnesium did not fulfil acceptance criteria. Evidence of interchangeability of patient results was obtained for all parameters except magnesium, NT-proBNP, cTroponin I and C-reactive protein.

Conclusions:

A laboratory having a well structured and documented validation procedure can opt to get a flexible scope of accreditation. In addition, performing these activities prior to use on patient samples may evidence technical issues which must be corrected to minimize their impact on patient results.  相似文献   
725.
Abstract

Currently, direct empirical evidence exists about the amount of mechanical load that climbers apply to each finger during several hand grips specific to sport climbing, but not yet in a specific hanging position.

The objectives of this study are a) to draw and build a solid and rigid support that simulates the real action of a hand grip in a hanging position in sport climbing, to enable the measurement of the mechanical load endured by the fingers in a hanging position and in addition, b) to describe the distribution of mechanical load among fingers as a function of the level of climbing during different hand grips in a hanging position.

Thirty young male participants took part in the initial phase of reliability of the measurements, while another 64 male climbers participated in the subsequent study phase to check the relations between independent and dependent variables. The level of on sight climbing and the total practice experience were used to define the groups. The research task consisted of performing hanging positions on the created support in order to measure the mechanical load endured by the fingers in the three most characteristic hand grips in climbing (crimp, half crimp and slope). It has been concluded that the performance level of the climbers had no influence on the production of a pattern of differentiated finger mechanical load during the research task.  相似文献   
726.
A contemporary view of early childhood motor development considers environmental influences as critical factors in optimal growth and behavior, with the home being the primary agent. However, there has been minimal research examining the relationship between motor development and the home. The present study addresses this gap with the goal of creating an innovative parental self-report instrument to assess the quality and quantity of factors (affordances and events) in the home that are conducive to enhancing motor development in children ages 18–42 months. Following initial face validity determination, expert opinion feedback and selective pilot testing, construct validity was examined using 321 Portuguese families. Factor analysis techniques were used to: (a) compare competing factorial models according to previous theoretical assumptions, and (b) analyze the fit of the preferred model. Of the five plausible models tested, the five-factor solution provided the best fit to the data. Reliability was established through the scale reliability coefficient with a value of .85. The findings of this study suggest that the Affordances in the Home Environment for Motor Development Self-Report is a valid and reliable instrument to assess how well home environments afford movement and potentially promote motor development.  相似文献   
727.
728.
Educational Studies in Mathematics - Mathematics discussions are important for helping students to develop conceptual understanding and to learn disciplinary norms and practices. In recent years,...  相似文献   
729.
This article offers an overview of mathematics education in Spain, analyzing the production of PhD theses over the last 30 years. This period has been divided into four cycles that describe the evolution of Spanish research in the field of mathematics education, together with changes in university and social politics. This paper also includes a forecast of the number of theses that will be produced over the next 7 years, thus predicting the future progress and development of this area of research.  相似文献   
730.
Curricula designed in the context of the European Higher Education Area need to be based on both domain-specific and professional competencies. Whereas universities have had extensive experience in developing students’ domain-specific competencies, fostering professional competencies poses a new challenge we need to face. This paper presents a model to globally develop professional competencies in a STEM (science, technology, engineering, and mathematics) degree program, and assesses the results of its implementation after 4 years. The model is based on the use of competency maps, in which each competency is defined in terms of competency units. Each competency unit is described by a set of expected learning outcomes at three domain levels. This model allows careful analysis, revision, and iteration for an effective integration of professional competencies in domain-specific subjects. A global competency map is also designed, including all the professional competency learning outcomes to be achieved throughout the degree. This map becomes a useful tool for curriculum designers and coordinators. The results were obtained from four sources: (1) students’ grades (classes graduated from 2013 to 2016, the first 4 years of the new Bachelor’s Degree in Informatics Engineering at the Barcelona School of Informatics); (2) students’ surveys (answered by students when they finished the degree); (3) the government employment survey, where former students evaluate their satisfaction of the received training in the light of their work experience; and (4) the Everis Foundation University-Enterprise Ranking, answered by over 2000 employers evaluating their satisfaction regarding their employees’ university training, where the Barcelona School of Informatics scores first in the national ranking. The results show that competency maps are a good tool for developing professional competencies in a STEM degree.  相似文献   
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