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Saboori P.,Manhattan College | Sadegh A.,City University
ASME International Mechanical Engineering Congress and Exposition, Proceedings (IMECE) | Year: 2012

The human head, being a vulnerable body region, is most frequently involved in traumatic brain injuries (TBI) and life threatening injuries. Accurate modeling of the variability of the brain morphology is a fundamental problem in investigating TBI. Improved computational/mathematical structural models of the brain are needed to help investigators to have a better understanding of the phenomena of different traumatic brain injuries such as concussion. The human brain is the most complex region of the body. There is a very thin membrane known as a pia mater that covers all the surface of the brain. The pia mater follows all the fissure of the brain and covers all the surface of the sulci and gyri. Sulcus is referred to any furrow in the brain. Statistically there are about 72 main sulci in the human brain. Previous FE studies of TBI have ignored sulcus morphology in their modeling and thus, their results could be unreliable. In this paper, the effect of the brain sulcus structure on mechanotransduction of impacts to the brain has been investigated. This was accomplished by using series of parametric studies and comparing the results with the model without sulci. The results of this study reveal that the brain's strain is reduced in the present of sulcus and gyrus structures. We have hypothesized that the presence of sulcus increases the surface area of the brain thereby decreases the normal and shear strain in the brain. That is, the presence of sulcus and gyrus reduce the transduction of the external load and impacts to the white and gray matters of the brain and thereby reduces the risk of TBI. Ignoring sulci in any FE modeling and analysis of the brain may lead to unreliable results. Copyright © 2012 by ASME.

Powell R.,University of Canterbury | Walker S.,City University | Barrett A.,Waikato Hospital
New Zealand Medical Journal | Year: 2015

The authors note significant room for improvement in facilitating informed consent in the management of breech presentation. New Zealand maternity care providers, including midwives, general practitioners and specialist obstetricians, have legal duties to provide full and unbiased information about risks and benefits of all relevant treatment options. In the case of breech presentation, such options include the interventions of external cephalic version or planned caesarean section, as well as the option to decline intervention and proceed with a planned vaginal breech birth. Information should be presented in a balanced and accessible way and not limited to the provider’s personal preferences. Women have legal rights to make an informed choice, to give or refuse consent, to a second opinion and to co-operation among providers. The right of competent persons to refuse medical treatment, including the right to refuse caesarean section, is well established. Clinical policies therefore should include appropriate and non-coercive care for women who choose to birth their breech-presenting baby vaginally, compliance with such policies should be the norm, and consideration should be given to any institutional reforms or educational priorities needed to achieve this. © NZMA.

Lu H.,Shanghai JiaoTong University | Yang G.,Shanghai JiaoTong University | Yeung L.F.,City University
Computers in Biology and Medicine | Year: 2011

This paper proposes a similarity matrix-based hybrid algorithm for the contact map overlap (CMO) problem in protein structure alignment. In this algorithm, Genetic Algorithm (GA) is used as a framework, in which the initial solutions are constructed with similarity matrix heuristic, and Extremal Optimization (EO) is embedded as a mutated operator. In this process, EO quickly approaches near-optimal solutions and GA generates improved global approximations. Five similarity measurements including ratio, inner product, cosine function, Jaccard index and Dice coefficient have been exploited to compute the similarity matrix between two contact maps. The simulations demonstrate that our algorithm is significantly faster and gets better results for most of the test sets. © 2011 Elsevier Ltd.

Esteve-Lanao J.,European University at Madrid | Larumbe-Zabala E.,Secretary of Education of the Government of the State of Yucatan | Dabab A.,European University at Madrid | Alcocer-Gamboa A.,Secretary of Education of the Government of the State of Yucatan | Ahumada F.,City University
International Journal of Sports Physiology and Performance | Year: 2014

The aim of this study was to describe the pacing distribution during 6 editions of the world cross-country championships. Methods: Data from the 768 male runners participating from 2007 to 2013 were considered for this study. Blocks of 10 participants according to final position (eg, 1st to 10th, 11 to 20th, etc) were considered. Results: Taking data from all editions together, the effect of years was found to be significant (F5,266= 3078.69, P < .001, ω2 = 0.31), as well as the effect of blocks of runners by final position (F4,266 = 957.62, P < .001, ω2 = 0.08). A significant general decrease in speed by lap was also found (F5,1330 = 2344.02, P < .001, ω2 = 0.29). Post hoc analyses were conducted for every edition where several pacing patterns were found. All correlations between the lap times and the total time were significant. However, each lap might show different predicting capacity over the individual outcome. Discussion: Top athletes seem to display different strategies, which allow them to sustain an optimal speed and/or kick as needed during the critical moments and succeed. After the first group (block) of runners, subsequent blocks always displayed a positive pacing pattern (fast to slow speed). Consequently, a much more stable pacing pattern should be considered to maximize final position. Conclusions: Top-10 finishers in the world cross-country championships tend to display a more even pace than the rest of the finishers, whose general behavior shows a positive (fast-to-slow) pattern. © 2014 Human Kinetics, Inc.

Travagin G.,University of Milan | Margola D.,University of Milan | Revenson T.A.,City University
Clinical Psychology Review | Year: 2015

This meta-analysis evaluated the effects of the expressive writing intervention (EW; Pennebaker & Beall, 1986) among adolescents. Twenty-one independent studies that assessed the efficacy of expressive writing on youth samples aged 10-18. years were collected and analyzed. Results indicated an overall mean g-effect size that was positive in direction but relatively small (0.127), as well as significant g-effect sizes ranging from 0.107 to 0.246 for the outcome domains of emotional distress, Problem Behavior, Social Adjustment, and School Participation. Few significant effects were found within specific outcome domains for putative moderator variables that included characteristics of the participants, intervention instructions, or research design. Studies involving adolescents with high levels of emotional problems at baseline reported larger effects on school performance. Studies that implemented a higher dosage intervention (i.e., greater number and, to some extent, greater spacing of sessions) reported larger effects on somatic complaints. Overall, the findings suggest that expressive writing tends to produce small yet significant improvements on adolescents' well-being. The findings highlight the importance of modifying the traditional expressive writing protocol to enhance its efficacy and reduce potential detrimental effects. At this stage of research the evidence on expressive writing as a viable intervention for adolescents is promising but not decisive. © 2015 Elsevier Ltd.

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