Coherence estimate between a random and a periodic signal: Bias, variance, analytical critical values, and normalizing transforms

The present work deals with recent results on the sampling distribution of the magnitude-squared coherence (also called just coherence) estimate between a random (Gaussian) and a periodic signal, in order to obtain analytical critical values, alternative expressions for the probability density function (PDF) as well as the variance and bias of the estimate. A comparison with the more general case of coherence estimation when both signals are Gaussian was also provided. The results indicate that the smaller the true coherence (TC) values the closer both distributions become. The behaviour of variance and bias as a function of the number of data segments and the TC is similar for both coherence estimates. Additionally, the effect of a normalizing function (Fisher's z transform) in the coherence estimated between a random and a periodic signal was also evaluated and normality has been nearly achieved. However, the variance was less equalized in comparison with coherence estimate between two Gaussian signals.     

Domestic patents and developing countries: arguments for their study and data from Brazil (1980–1995)

This paper presents data from Brazilian Patent Office (Instituto Nacional de Propriedade Industrial, INPI) and compares them with data from the United States Patent Office (USPTO). Developing countries have technological activities that are important locally but not significant at international level (imitation, local learning, adaptation of foreign innovations). These activities might be patentable only at national level. Therefore, the study of domestic patents of developing countries provides a broader picture than USPTO patents. This paper compares 8309 INPI patents with 475 USPTO patents (between 1980 and 1995). Domestic patent data show peculiarities in the Brazilian case, possibly shared with other countries in similar technological level: (a) high share of individual patents; (b) foreign-owned firms with important activities; (c) low firm involvement in R&D activities. Some characteristics are shared with developed countries: (a) domestic firms as the major patentees; (b) according to firm size, there is a U-shaped distribution of patents; (c) evidences of multi-technology large firms; (d) a relatively small share of firms have more than one patent in the whole period. The contrast between USPTO and national patenting statistics shows different rankings according to ownership structure, leading firms, industrial sectors, and international patent classification. These differences highlight sources of international competitiveness and point to weaknesses in Brazilian innovative activities. This paper concludes evaluating the contributions (and weaknesses) of this database for the evaluation of the Brazilian National System of Innovation.     

Effects and prevalence of responders after a multicomponent intervention on cardiometabolic risk factors in children and adolescents with overweight/obesity: Action for health study

ABSTRACT

This study aimed to verify the effect of a multicomponent intervention on cardiometabolic risk factors (CMRF), and to determine the prevalence of responders on CMRF among children and adolescents with overweight/obesity. This is a quasi-experimental study, developed with 35 children and adolescents with overweight/obesity (control group (CG) = 18; intervention group (IG) = 17), aged between 7 and 13 years. Participants in IG underwent a multicomponent intervention for 12 weeks. The following variables were evaluated: anthropometric measures, maturational stages and CMRF (body fatness, HOMA-IR, triglycerides, high-density and low-density lipoprotein) (HDL-C, LDL-C), total cholesterol (TC), aspartate aminotransferase (AST), alanine aminotransferase (ALT) and AST/ALT ratio. Mixed analysis of variance and the prevalence of responders were used for statistical analysis. There was a significant time x group interaction on body fatness (p < 0.001), HOMA-IR (p = 0.01), HDL-C (p < 0.001), LDL-C (p = 0.009) and TC (p < 0.001). The prevalence of responders for CMRF in IG and CG was respectively: body fatness (47%; 0%; p = 0.04), HOMA-IR (58.8%; 16.6%; p = 0.04); triglycerides (17.6%; 5.5%; p = 0.31); HDL-C (76.4%; 5.5%; p = 0.01), LDL-C (35.3%; 5%; p = 0.08), TC (64.7%; 5%; p = 0.01), AST (5.8%; 0%; p = 0.87), ALT (29.4%; 11.1%; p = 0.24) and AST/ALT ratio (24.4%; 22.2%; p = 0.67). Multicomponent intervention induced positive changes on CMRF along with a higher prevalence of positive adaptations in IG than the CG in some of the cardiometabolic outcomes assessed.     

Conceptual change or Conceptual Profile change?

In this paper I draw an overview of a new model to analyse conceptual evolution in the classroom, based on the notion of Conceptual Profile. This model differs from conceptual change models in suggesting that it is possible to use different ways of thinking in different domains and that a new concept does not necessarily replace previous and alternative ideas. According to this model, learning science is to change a conceptual profile and become conscious of the different zones of the profile, which includes commonsense and scientific ideas.To exemplify how the Conceptual Profile notion can help to understand the evolution of conceptions in the classroom I shall determine the different zones that constitute the epistemological and ontological profile of the concepts of the atom and of physical states of matter.     

Flipping the Classroom in Freshman English Library Instruction: A Comparison Study of a Flipped Class Versus a Traditional Lecture Method

A problem that Instruction Librarians often grapple with is the lack of time that is necessary to deliver, and assess, proper library instruction to students so the students grasp the Information Literacy concepts that are delivered especially in one or two instruction sessions. This article examines using the flipped classroom model in English library instruction classes where the works cited page of students final paper was assessed according to a rubric designed to assess the Authority, Timeliness, and Variety of the sources cited. The study compared results of flipped classroom sections against traditional lecture method classes with mixed results.     

Mean Effects of Test Accommodations for ELLs and Non‐ELLs: A Meta‐Analysis of Experimental Studies

The objective was to examine the impact of different types of accommodations on performance in content tests such as mathematics. The meta‐analysis included 14 U.S. studies that randomly assigned school‐aged English language learners (ELLs) to test accommodation versus control conditions or used repeated measures in counter‐balanced order. Individual effect sizes (Glass's d) were calculated for 50 groups of ELLs and 32 groups of non‐ELLs. Individual effect sizes for English language and native language accommodations were classified into groups according to type of accommodation and timing conditions. Means and standard errors were calculated for each category. The findings suggest that accommodations that require extra printed materials need generous time limits for both the accommodated and unaccommodated groups to ensure that they are effective, equivalent in scale to the original test, and therefore more valid owing to reduced construct‐irrelevant variance. Computer‐administered glossaries were effective even when time limits were restricted. Although the Plain English accommodation had very small average effect sizes, inspection of individual effect sizes suggests that it may be much more effective for ELLs at intermediate levels of English language proficiency. For Spanish‐speaking students with low proficiency in English, the Spanish test version had the highest individual effect size (+1.45).     

Primeras creaciones en el lenguaje infantil. El caso de las metáforas

Resumen

La mayoría de los autores reconoce que el niño crea múltiples términos y expresiones cuando empieza a hablar. Estas creaciones (muchas veces erróneas desde nuestro punto de vista), revelan el empleo de diferentes reglas lingüísticas.

Uno de los motivos que conducen al niño pequeño a crear nuevos términos es el metafórico: designar un objeto con un término que normalmente se aplica a otro objeto, similar al primero. Podríamos entonces pensar que el niño, de dos a seis años, es capaz de emplear y comprender el lenguaje figurado, y particularmente las metáforas. Esta hipótesis es criticada a la luz de una serie de hechos experimentales relativos al desarrollo cognitivo del niño.     

Some practical approaches to a course on paraconsistent logic for engineers

This paper describes a non-classical logic course primarily indicated for graduate students in electrical engineering and energy engineering. The content of this course is based on the vision that it is not enough for a student to indefinitely accumulate knowledge; it is necessary to explore all the occasions to update, deepen, and enrich that knowledge, adapting it to a complex world. Therefore, this course is not tied to theoretical formalities and tries at each moment to provide a practical view of the non-classical logic. In the real world, the inconsistencies are important and cannot be ignored because contradictory information brings relevant facts, sometimes modifying the entire result of the analysis. As consequence, the non-classical logics, such as annotated paraconsistent logic – APL, are efficiently framed in the approach of complex situations of the real world. In APL, the concepts of unknown, partial, ambiguous, and inconsistent knowledge are referred not to trivialise any system in analysis. This course presents theoretical and applicable aspects of APL, which are successfully used in decision-making structures. The course is divided into modules: Basic, 2vAPL, 3vAPL, 4vAPL, and Final Project.     

From body to culture: the need for a developmental psychology view. A commentary on the article Learning beyond the body by Juan-Ignacio Pozo / Del cuerpo a la cultura: la necesidad de una mirada desde la psicología del desarrollo. Un comentario sobre el artículo Aprender más allá del cuerpo de Juan-Ignacio Pozo

The necessity of adopting a developmental perspective to understand the role that the body and action play in children’s representations is argued in proposals made by Pozo in his article Learning beyond the body: from embodied representations to explicitation mediated by external representations. The transformative power of action is valued from this developmental perspective, while at the same time revealing the close link between action, cognition and communication. Similarly, the explicitation and implicitation processes are considered to be recurrent phases that occur in any stage of development, applied to embodied knowledge as well as to more elaborate and explicit knowledge.