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Associations between physical activity and BMI, body fatness, and visceral adiposity in overweight or obese Latino and non-Latino adults.
Background/objectivesAlthough several studies have reported associations between moderate to vigorous physical activity (MVPA), body fatness and visceral adipose tissue (VAT), the extent to which associations differ among Latinos and non-Latinos remains unclear. This study evaluated the associations between body composition and MVPA in Latino and non-Latino adults.Subjects/methodsAn exploratory, cross-sectional analysis was conducted using baseline data collected from 298 overweight adults enrolled in a 12-month randomized controlled trial that tested the efficacy of text messaging to improve weight loss. MVPA, body fatness and VAT were assessed by waist-worn accelerometry, dual-energy x-ray absorptiometry (DXA), and DXA-derived software (GE CoreScan GE, Madison, WI, USA), respectively. Participants with <5 days of accelerometry data or missing DXA data were excluded; 236 participants had complete data. Multivariable linear regression assessed associations between body composition and MVPA per day, defined as time in MVPA, bouts of MVPA (time per bout ⩾10 min), non-bouts of MVPA (time per bout <10 min) and meeting the 150-min MVPA guideline. The modifying influence of ethnicity was modeled with a multiplicative interaction term.ResultsThe interaction between ethnicity and MVPA in predicting percent body fat was significant (P=0.01, 95% confidence interval (CI) (0.58, 4.43)) such that a given increase in MVPA was associated with a greater decline in total body fat in non-Latinos compared with Latinos (adjusted for age, sex and accelerometer wear time). There was no interaction between ethnicity and MVPA in predicting VAT (g) (P=0.78, 95% CI (-205.74, 273.17)) and body mass index (BMI) (P=0.18, 95% CI (-0.49, 2.26)).ConclusionsAn increase in MVPA was associated with a larger decrease in body fat, but neither BMI nor VAT, in non-Latinos compared with Latinos. This suggests that changes in VAT and BMI in response to MVPA may be less influenced by ethnicity than is total body fatness
Introductory research activities in mathematics education
Se presentan algunas actividades prácticas propuestas en un curso de innovación docente e iniciación a la investigación educativa en el marco de un máster de formación inicial de profesores de matemáticas de secundaria. Se incluyen, entre otros ejemplos, el análisis de un texto breve en el que se describe una clase ideal de matemáticas y el análisis de una sesión de clase video-grabada sobre semejanza de triángulos. Estos ejemplos se introducen con el fin de reflexionar sobre algunos principios didáctico-matemáticos básicos, los cuales permiten introducir criterios de idoneidad didáctica en el estudio de las matemáticas y motivar la búsqueda de fuentes bibliográficas en la base de datos MathEduc.This paper presents some practical activities
carried out in
a teaching
innovation and introduction to educational research
course, which is part of
a Master’s degree
directed to
secondary mathematics teachers’ initial e
ducation.
A
mong other examples
we include
the analysis of a short text describing
an
ideal mathematics class
room
and the analysis of a video
-
recorded
lesson
on
similarity of triangles. These activities serve
to reflect on some basic
mathematical didactic principles,
to
introduce
educational suitability criteria in
the study of mathematics and
to
motivate the
review of
literature
in
the
MathEduc database
Seagrass debris as potential food source to enhance Holothuria arguinensis' growth in aquaculture
Holothuria arguinensis aquaculture started to be developed in 2014, being the first sea cucumber species from Europe. However, some aspects of its aquaculture biotechnology, such diets, need to be assessed. This work aimed to evaluate seagrass debris of Zostera noltii and Cymodocea nodosa as food source for broodstock maintenance in tanks, during breeding periods. The given feed rations per tank were calculated as the 30% of the total sea cucumber biomass in each tank and reviewed each week. Then, feed rations of seagrass and sediment were calculated from this value, according to the following percentages: 40% sediment, 15% Z. noltii, 40% Z. noltii, 15% C. nodosa and 40% C. nodosa. H. arguinensis growth, feeding rate and nutritional value were assessed under these diets. H. arguinensis fed with 40% of Z. noltii showed the highest growth (specific growth rate = 0.09 +/- 0.06%/day, absolute growth rate = 0.11 +/- 0.07 g/day) increasing their final weight in 5.86 +/- 3.57% in 57 days. However, the individuals fed with C. nodosa showed a negative growth. H. arguinensis showed a reduction in its feeding rate as the organic matter content in the diets increased. H. arguinensis did not show any important change on proximate composition, protein, lipid, mineral contents and fatty acids profile among the feeding groups, or in comparison with the individuals collected from wild habitat. Therefore, H. arguinensis could be fed with Z. noltii debris during tanks maintenance along breeding period, ensuring its growth and maintaining its nutritional profile.Fundacao para a Ciencia e a TecnologiaPortuguese Foundation for Science and TechnologyEuropean Commission [CCMAR/SC/BI/02/2016, FRH/BD/105541/2014, IF/00049/2012, IF/00998/2014, PTDC/MAR-BIO/5948/2014, PTDC/MAR/119363/2010, SFRH/BPD/70689/2010]http://creativecommons.org/licenses/by/4.0
Aplicación de indicadores de idoneidad afectiva en un proceso de enseñanza de probabilidad en educación secundaria
La reflexión docente es una herramienta fundamental de la innovación didáctica. En este artículo se describe y analiza una experiencia reflexiva sobre la idoneidad afectiva de un proceso de estudio sobre probabilidad en educación secundaria, con el objetivo de mostrar su utilidad para identificar mejoras y explicar fenómenos didácticos que tienen lugar en la implementación. El método empleado es de carácter cualitativo, descriptivo e interpretativo, basado en la aplicación de indicadores de idoneidad afectiva para valorar el grado de adecuación a los condicionantes del contexto y para identificar hechos didácticos significativos. Como resultado se ofrece una guía de aplicación de los indicadores de idoneidad afectiva en un proceso de estudio concreto de probabilidad. Finalmente, en las conclusiones, tras establecer las mejoras que pueden realizarse en el proceso que se ha considerado, se señala la pertinencia de este tipo de análisis reflexivo como herramienta de innovación docente
Probabilidade de acontecimentos envolvendo aspetos lógicos
In this article, we study the Probability's knowledge of prospective primary school teachers, when there are logical aspects involved in the formulation of events. Forty-six students participated in the study, from a University in Northern Portugal, who had to resolve a three-item task in the context of a formal evaluation: the first one, on the union probability (connective or), the second one, on the joint probability (connective and), and the third one, on the conditional probability, in which the conditioned event is, in turn, a joint probability (connective and). In terms of the main results of the study, it was found that the students showed a very limited performance, frequently changing the connectives and and or, the inclusive disjunction with the exclusive disjunction and in the disjunction considered as incompatible non-disjoint events.Neste artigo estuda-se o conhecimento de Probabilidades de futuros professores dos primeiros anos escolares,
quando na formulação dos acontecimentos estão envolvidos aspetos lógicos. Participaram no estudo 46 alunos da Licenciatura em Educação Básica, de uma Universidade do Norte de Portugal, os quais resolveram uma tarefa, com três itens, em contexto de avaliação formal: o primeiro sobre a probabilidade da reunião (conetivo ), o segundo sobre a probabilidade conjunta (conetivo ) e o terceiro sobre a probabilidade condicionada, em que o acontecimento condicionado é, por sua vez, uma probabilidade conjunta (conetivo ). Em termos dos principais resultados do estudo, verificou-se que os alunos revelaram um desempenho muito limitado, trocando, frequentemente, os conetivos e , a disjunção inclusiva com a disjunção exclusiva e na disjunção consideraram como sendo incompatíveis acontecimentos não disjuntos.Este trabalho contou com o apoio de Fundos Nacionais através da FCT – Fundação para a Ciência e a Tecnologia no âmbito do projeto PEst-OE/CED/UI1661/2014, do CIEd-UM e do projeto UID/Multi/04016/2016
Una experiencia de formación matemática de maestros usando recursos informáticos
En este trabajo describimos el diseño e implementación de un módulo de clases prácticas en el aula de informática, que se ha llevado a cabo en el programa de formación inicial de maestros de educación primaria en el área de matemáticas de la Universidad de Granada. Analizamos la organización de las sesiones prácticas y el tipo de activida- des basadas en la exploración y análisis de una colección de “applets” sobre aritmética, geometría, medida y estadística. Presentamos también algunos resultados de la experien- cia y unas primeras conclusiones sobre las cuestiones de investigación que plantea la incorporación de las nuevas tecnologías en los procesos de enseñanza y aprendizaje de las matemáticas cuando se realiza en este tipo de escenarios presenciales
Altered gene expression in human placenta after suspected preterm labour
Introduction Suspected preterm labour occurs in around 9% of pregnancies. However, almost two-thirds of women admitted for threatened preterm labour ultimately deliver at term and are considered risk-free for fetal development. Methods We examined placental and umbilical cord blood samples from preterm or term deliveries after threatened preterm labour as well as term deliveries without threatened preterm labour. We quantitatively analysed the mRNA expression of inflammatory markers (IL6, IFN?, and TNFa) and modulators of angiogenesis (FGF2, PGF, VEGFA, VEGFB, and VEGFR1). Results A total of 132 deliveries were analysed. Preterm delivery and term delivery after suspected preterm labour groups showed similar increases in TNFa expression compared with the term delivery control group in umbilical cord blood samples. Placental samples from preterm and term deliveries after suspected preterm labour exhibited significantly increased expression of TNFa and IL6 and decreased expression of IFN?. Suspected preterm labour was also associated with altered expression of angiogenic factors, although not all differences reached statistical significance. Discussion We found gene expression patterns indicative of inflammation in human placentas after suspected preterm labour regardless of whether the deliveries occurred preterm or at term. Similarly, a trend towards altered expression of angiogeneic factors was not limited to preterm birth. These findings suggest that the biological mechanisms underlying threatened preterm labour affect pregnancies independently of gestational age at birth
Characterizing and predicting person-specific, day-to-day, fluctuations in walking behavior
Despite the positive health effect of physical activity, one third of the world's population is estimated to be insufficiently active. Prior research has mainly investigated physical activity on an aggregate level over short periods of time, e.g., during 3 to 7 days at baseline and a few months later, post-intervention. To develop effective interventions, we need a better understanding of the temporal dynamics of physical activity. We proposed here an approach to studying walking behavior at "high-resolution" and by capturing the idiographic and day-to-day changes in walking behavior. We analyzed daily step count among 151 young adults with overweight or obesity who had worn an accelerometer for an average of 226 days (~25,000 observations). We then used a recursive partitioning algorithm to characterize patterns of change, here sudden behavioral gains and losses, over the course of the study. These behavioral gains or losses were defined as a 30% increase or reduction in steps relative to each participants' median level of steps lasting at least 7 days. After the identification of gains and losses, fluctuation intensity in steps from each participant's individual time series was computed with a dynamic complexity algorithm to identify potential early warning signals of sudden gains or losses. Results revealed that walking behavior change exhibits discontinuous changes that can be described as sudden gains and losses. On average, participants experienced six sudden gains or losses over the study. We also observed a significant and positive association between critical fluctuations in walking behavior, a form of early warning signals, and the subsequent occurrence of sudden behavioral losses in the next days. Altogether, this study suggests that walking behavior could be well understood under a dynamic paradigm. Results also provide support for the development of "just-in-time adaptive" behavioral interventions based on the detection of early warning signals for sudden behavioral losses
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