The impact of different types of physical activity on total and regional bone mineral density in young Brazilian athletes

Bone turnover is affected by exercise throughout the lifespan, especially during childhood and adolescence. The objective of this study was to investigate the impact of different sports on total and regional bone mineral density in male Brazilian adolescent athletes. Forty-six adolescents aged 10-18 years participated in the study: 12 swimmers, 10 tennis players, 10 soccer players, and 14 sedentary individuals. The athletes had engaged in physical activities for more than 10 h per week in the previous 6 months. Bone mineral density of the lumbar spine (L1-L4), left proximal femur region, and whole body was evaluated by dual-energy X-ray absorptiometry. Results showed higher mean values in the proximal femur region of tennis and soccer players (1.02 ± 0.18; 0.96 ± 0.16, respectively) than swimmers and controls (0.91 ± 0.14 and 0.87 ± 0.06, respectively) (P < 0.05). In relation to the impact of sporting activities based on bone age determination, we observed significant differences in bone mineral density at all evaluated sites at the end of puberty (16-18 years) compared with 10-12 years, with increases of 78% in the lumbar spine, 47% in the proximal femur, and 38% in the whole body.     

The Roles of Engagement at The Ohio State University Libraries: Thoughts from an Early Adopter

Changes in information and technology continue to test how librarians interact with and support patrons. Now, engaged librarians have the opportunity to immerse themselves in their user’s workflows and become partners in the research enterprise. Engagement represents a model of librarianship in which librarians are challenged to move from the traditional collection-centered model to an engaged-focused one. It requires new roles and tasks, as well as a deeper understanding of the academic setting. This article discusses working in a large research institution and articulates the engagement model.     

A tapered channel microfluidic device for comprehensive cell adhesion analysis, using measurements of detachment kinetics and shear stress-dependent motion

We have developed a method for studying cellular adhesion by using a custom-designed microfluidic device with parallel non-connected tapered channels. The design enables investigation of cellular responses to a large range of shear stress (ratio of 25) with a single input flow-rate. For each shear stress, a large number of cells are analyzed (500–1500 cells), providing statistically relevant data within a single experiment. Besides adhesion strength measurements, the microsystem presented in this paper enables in-depth analysis of cell detachment kinetics by real-time videomicroscopy. It offers the possibility to analyze adhesion-associated processes, such as migration or cell shape change, within the same experiment. To show the versatility of our device, we examined quantitatively cell adhesion by analyzing kinetics, adhesive strength and migration behaviour or cell shape modifications of the unicellular model cell organism Dictyostelium discoideum at 21 °C and of the human breast cancer cell line MDA-MB-231 at 37 °C. For both cell types, we found that the threshold stresses, which are necessary to detach the cells, follow lognormal distributions, and that the detachment process follows first order kinetics. In addition, for particular conditions’ cells are found to exhibit similar adhesion threshold stresses, but very different detachment kinetics, revealing the importance of dynamics analysis to fully describe cell adhesion. With its rapid implementation and potential for parallel sample processing, such microsystem offers a highly controllable platform for exploring cell adhesion characteristics in a large set of environmental conditions and cell types, and could have wide applications across cell biology, tissue engineering, and cell screening.     

Differences between web sessions according to the origin of their visits

The aim of this paper is to characterize the distribution of number of hits and spent time by web session. It also expects to find if there are significant differences between the length and the duration of a session with regard to the point of access–search engine, link or root. Web usage mining was used to analyse 17,174 web sessions that were identified from the webometrics.info web site. Results show that both distribution of length and duration follow an exponential decay. Significant differences between the different origins of the visits were also found, being the search engines’ users those who spent most time and did more clicks in their sessions. We conclude that a good SEO policy would be justified, because search engines are the principal intermediaries to this web site.     

Training and psychosocial patterns during the early development of Portuguese national team athletes

This study explored the early development of expert athletes compared to a group of athletes that did not achieve an expert level of performance despite being involved in youth events with their national squads. In particular, the activities, training patterns, and psychosocial influences that characterized their paths in competitive sports were examined. Male and female participants (N?=?42) from different sports were interviewed. Overall, athletes showed several commonalities. However, experts were selected to national squads later and also started thinking about investing in becoming elite athletes later. Non-experts revealed more parental pressure and less individual training with coaches.     

Mentoring Matters: An Exploratory Survey of Educational Leadership Doctoral Students’ Perspectives

There is limited research on quantitative differences between men and women’s experiences in doctoral programs. We aim to fill that gap by sharing findings from a web-based exploratory survey of perceived gender differences on quality mentoring in educational leadership doctoral programs. According to survey results, there is limited statistical significance in terms of gender differences in programmatic supports and scholarly progress. However, women experience feelings of self-doubt due to negative experiences with advising and mentoring, including difficulties making connections to a quality mentor. Furthermore, both female and male participants shared common definitions of what constitutes quality mentorship and believed mentorship was important, but lacking in varying degrees. Finally, all participants agreed that their educational leadership preparation programs should provide additional support in terms of writing and research development. Participants also shared important recommendations for strengthening mentoring experiences as well as future research methods and foci.     

Learning by starch potato growers: learning in small businesses with no employees

In small businesses with no employees, learning environments have a low learning readiness. Consequently, learners need to rely on their own agency to shape their learning experiences. Results from a study of agricultural entrepreneurs indicated that the components of motivation and self-regulated learning strategies shape learner's agency and explain learning environment configuration in small businesses with no employees. Configuration of the learning environment was found to be a weak determinant of the learning performance of these learners. However, results showed that prior performance of learners in small businesses with no employees dictates how their agency operates and what learning effect is achieved; higher prior performance results in higher learning effects. We conclude that mechanisms that underlie learning in traditional learning environments work similarly in learning environments in small businesses with no employees.     

Revisando algunos aspectos de la educación bilingüe

Tras más de una década de enseñanza bilingüe en que muchos niños españoles han sido educados en dos o más de las lenguas del país, el autor revisa lo realizado y sus efectos y reflexiona sobre las consecuencias educativas a extraer. A este hecho hace propuestas didácticas concretas tanto en cuanto qué módulos de inmersión son viables como en cuanto a las actuaciones dentro de ellos.     

Teachers reflecting on their work: articulating what is said about what is done

Teachers' written reflections on their work, which report on a change in their practice, were the object of this research. Taking teachers' articulation of their plans and actions in teacher journals as our source, this study's aim is twofold: (1) to describe how teacher reflect in a self‐initiated and non‐framed way on their own practice, and (2) to review teacher self generated reflections in reference to models of reflection. In this way, we tried to disclose what precisely teachers write (said) when reflecting on their work (did) in order to appreciate their way of describing what matters in their work; and position this in reference to models that conceptualise (“talk”) on how to actualise (‘walk’) reflection. This ‘double’ articulation of reflection is gauged in two ways, i.e., on: a) completeness, that is, whether it includes relevant components of reflection (models) to be found in the literature, and on b) recursiveness, that is, whether the written account gives evidence of an integrated cyclical, i.e., recursive process of re‐view, which appraises and looks back on what has been accomplished.

The results show that teachers do not work along the lines identified in current reflection models (i.e. providing clear problem definition, searching for evidence, planning for change, and reviewing plans). Instead, many teachers use a narrative and valuing appraisal of their accomplishments; not so much cautiously reviewing their actions but prospectively commenting on plans and solutions for future action. The data lead us to be cautious about the prominence of reflection models as advocated in the literature to be applied to teachers' written accounts of their practice.