Body fat measurement in elite sport climbers: Comparison of skinfold thickness equations with dual energy X-ray absorptiometry

Abstract

The aim of this study was to compare equations for estimating percentage body fat from skinfold thickness in elite sport climbers by assessing their agreement with percentage body fat measured using dual-energy X-ray absorptiometry (DXA). Skinfold thickness was measured in a convenience sample of 19 elite sport climbers [9 women and 10 men; mean age 31.2 years (s = 5.0) and 28.6 years (s = 3.6), respectively]. Percentage body fat was estimated using 17 different equations, and it was also measured by DXA. A significant inter-methods difference was observed for all equations, except for Durnin's equation in men (inter-methods difference: ?0.57% and ?0.29%; 1.96 s: 5.56 and 5.23 for Siri's and Brozek's equation, respectively) and women (inter-methods difference: ?0.67% and ?1.29% for Siri's and Brozek's equation, respectively), and for Wilmore's equation using Siri's body fat equation in women (inter-methods difference: ?1.86%). In women, the limits of agreement were lower when using Durnin's equation compared with Wilmore's equation (1.96 s: 3.86% and 5.13%, respectively). In conclusion, of the 17 studied equations, Durnin's equation was the most accurate in estimating percentage body fat in both male and female elite climbers. Therefore, Durnin's equation could be used to assess percentage body fat in elite sport climbers if more accurate methods are not available. The generalizability of the results is limited by the fact that the sample was not selected at random.     

Vitamin C supplementation does not influence plasma and blood mononuclear cell IL-6 and IL-10 levels after exercise

Abstract

The aim of this study was to determine whether the highest vitamin C supplementation associated with complete bioavailability influences the plasma and blood mononuclear cell IL-6 and IL-10 response to exercise. A double-blinded study of supplementation with vitamin C was performed. After 15 days of supplementation with vitamin C (500 mg · day^?1, n = 16) or a placebo (n = 15), participants in the study completed a 15-km run competition. Blood samples were taken before and after competition. Oxidative stress markers, antioxidants, cortisol, IL-6 and IL-10 were determined in plasma or serum. IL-6 and IL-10 protein and mRNA levels were measured in blood mononuclear cells. Although higher plasma and blood mononuclear cell vitamin C levels were observed in the supplemented group when compared with the placebo one, the two groups showed identical exercise-induced changes in all the measured parameters. Exercise induced increased IL-6 and IL-10 levels in plasma and blood mononuclear cells. IL-6 and IL-10 mRNA levels in blood mononuclear cells increased after the competition. After recovery, IL-6 mRNA returned to basal levels and IL-10 mRNA levels remained elevated. In conclusion, exercise induced increased IL-6 and IL-10 production in blood mononuclear cells. However, vitamin C supplementation did not influence IL-6 and IL-10 response to exercise.     

«Un redondel con muchas cosas dentro». Eso es un conjunto

Resumen

Se examina la comprensión infantil de algunas nociones de la teoría de conjuntos en una muestra de sesenta niños madrileños entre 6 y 11 años de edad. El análisis se centra en la definición y reconocimiento de conjuntos por parte de los niños, la formación de conjuntos a partir de un material dado y la conciencia de la utilidad de los conjuntos y su relación con otras áreas de las Matemáticas. Los resultados indican que más del 50% de los sujetos identifica el conjunto con el diagrama que lo representa y son incapaces de aplicar esas nociones a problemas concretos. Se interpretan estas dificultades a la luz de la descripción piagetiana de los dos tipos de abstracción—empírica y reflexiva—, y los dos tipos de conocimiento—físico y lógico-matemático—a que dan lugar.     

A Lost Decade? Laszlo Radvanyi and the Origins of Public Opinion Research in Mexico, 1941-1952

This article documents public opinion research activities inMexico in the 1940s and the role played by Hungarian professorLászló Radványi, who immigrated to thatcountry at the height of World War II. Our research relies onseveral of Radványi's publications archived in differentcountries, as well as on interviews with family, acquaintances,and experts on the work of his wife, the German poet Anna Seghers.During his years in Mexico, Radványi founded the ScientificInstitute of Mexican Public Opinion, in 1941, and the InternationalJournal of Opinion and Attitude Research, in 1947—a forefatherof today's IJPOR. He was also a founding member of WAPOR. Hisearly "sample surveys" raised important methodological issuesand recorded opinion results that reflect the vibrant timesof war and policy making in a modernizing country. However,Radványi's contribution to the profession has been virtuallyforgotten. Until now, accounts about how public opinion researchbegan in Mexico either ignored Radványi's works or reducedhis ten years of survey research to a single footnote. Thisarticle is an attempt to fill this enormous omission and highlightsome of Radványi's contributions to these early stagesof survey research.     

A computer-supported learning system to help teachers to teach Fuzzy Information Retrieval Systems

This paper describes a computer-supported learning system to teach students the principles and concepts of Fuzzy Information Retrieval Systems based on weighted queries. This tool is used to support the teacher’s activity in the degree course Information Retrieval Systems Based on Artificial Intelligence at the Faculty of Library and Information Sciences at the University of Granada. Learning of languages of weighted queries in Fuzzy Information Retrieval Systems is complex because it is very difficult to understand the different semantics that could be associated to the weights of queries together with their respective strategies of query evaluation. We have developed and implemented this computer-supported education system because it allows to support the teacher’s activity in the classroom to teach the use of weighted queries in FIRSs and it helps students to develop self-learning processes on the use of such queries. We have evaluated the performance of its use in the learning process according to the students’ perceptions and their results obtained in the course’s exams. We have observed that using this software tool the students learn better the management of the weighted query languages and then their performance in the exams is improved.

Deaf children's use of phonological coding: evidence from reading, spelling, and working memory

Two groups of deaf children, aged 8 and 14 years, were presented with a number of tasks designed to assess their reliance on phonological coding. Their performance was compared with that of hearing children of the same chronological age (CA) and reading age (RA). Performance on the first task, short-term recall of pictures, showed that the deaf children's spans were comparable to those of RA controls but lower than CA controls. For the older deaf children, short-term memory span predicted reading ability. There was no clear evidence that the deaf children were using phonological coding in short-term memory when recall of dissimilar items was compared with recall of items with similarly sounding names. In the second task, which assessed orthographic awareness, performance of the deaf children was similar to that of RA controls although scores predicted reading level for the deaf children but not the hearing. The final task was a picture spelling test in which there were marked differences between the deaf and hearing children, most notably in the number of spelling refusals (which was higher for the deaf children in the older group than their RA controls) and the percentage of phonetic errors (which was considerably lower for both groups of deaf children than for any of the hearing controls). Overall these results provide support for the view that deaf children place little reliance on phonological coding.     

The conceptual evolution of actual mathematical infinity

The different stages in the conceptual evolution of actual infinity are analyzed. We show how this concept occurs in high-school students at a prior, or at best, at the same level, as in Bernard Bolzano's conceptualization (as defined in his work The Paradoxes of Infinity). Furthermore, in terms of the historical development of the concept, the students' conceptualization has intra-objectal stage characteristics. Within the same framework, we show how Cantor's work fits into the inter-objectal stage, as well as presenting the difficulties encountered by students in order to reach this stage, given the current curricular structure. We conclude that such evidence should bring about a reconsideration of Piagetian ideas in education.     

Bringing local voices into community revitalization: engaged communication research in Urban planning

The need to better engage low-income communities affected by revitalization of the built environment has been well documented in urban planning. Guided by communication infrastructure theory (CIT), this study presents a research project that made concerted efforts at engaging neighborhoods of Northeast Los Angeles that are experiencing rapid gentrification. The project was a partnership with a multi-sector collaborative working on the revitalization of the L.A. River and its surrounding communities. This paper specifically demonstrates how CIT's social ecological orientation was applied to seek input on L.A. River and community revitalization from storytelling networks made up of residents, small businesses, and local media. We also examine the impact of this engaged research on the organizational partners of the collaborative, and their views on community engagement in revitalization. Lastly, we discuss how the lessons learned broadly speak to future opportunities and challenges that aim for communicative planning approaches to urban revitalization.     

Investigating the double-deficit hypothesis of developmental dyslexia in an orthography of intermediate depth

The present study aimed to investigate the double-deficit hypothesis (DDH) in an orthography of intermediate depth. Eighty-five European Portuguese-speaking children with developmental dyslexia, aged 7 to 12, were tested on measures of phonological awareness (PA), naming speed (NS), reading, and spelling. The results indicated that PA and NS were not significantly correlated, and that NS predicts reading fluency (but not reading accuracy and spelling) beyond what is accounted for by PA. Although the majority of the children with developmental dyslexia have double deficit (62.4%), some children have a single phonological deficit (24.7%) or a single NS deficit (8.2%). Children with a double deficit were not more impaired in reading fluency, reading accuracy, and spelling than both single-deficit subtypes. In conclusion, the findings of the present study are partially consistent with the DDH and provide evidence for the multifactorial model of developmental dyslexia. Implications of the DDH for an orthography of intermediate depth are emphasized.

     

Characteristics of Successful Collaborations to Produce Educated Software Engineering Professionals

Currently, a large gap exists between the number of open software engineering positions and the number of qualified software engineers to fill those positions. The Industry/University (I/U) subgroup of the Working Group on Software Engineering Education and Training (WGSEET) is investigating active collaborations between companies and universities in which non-software professionals and practitioners without formal software education are reeducated to become software engineers. This paper describes the current status of work performed by the I/U subgroup in the investigation of reeducation collaborations. It is our goal to identify the common characteristics of successful collaborations in order to provide guidance to universities and companies when constructing a collaborative program, as well as to promote future collaborations. In this paper, we report on the current activity of the I/U subgroup, describe the features of successful collaborations identified so far in our research, and provide some conclusions as to the usefulness of such collaborations.