Improving health outcomes for girls : reflections on the impact on body issue of a girl\u27s only health and physical education intervention

Background: The issues surrounding girls' lack of participation in physical activity are many and varied, but\ud generally relate to the broader social context of adolescent health in which the social relations of gender play a significant part in a lack of engagement with sports; with a lack of physical skills and confidence for\ud equitable participation; friendship considerations; body image issues and a concern about bullying and\ud harassment.\ud \ud Objectives: This paper reports on data collected as part of a larger project researching the impact of a non-traditional physical education and health intervention designed to build girls connectedness to each other,\ud their school and their community by engaging them in a girls' only negotiated physical activity program that\ud was supported by a targeted health education curricula.\ud \ud Underlying values and principles: Grade 8 girls in the State of Victoria, Australia have the lowest school\ud connectedness data than any other cohort. Using youth participation principles and underpinned by strong\ud educational guidelines an integrated health and physical education program was developed by a high school\ud in Australia in an attempt to improve connectedness. It facilitated the exploration of a number of different\ud lifestyle physical activities such as bellying dance, self-defense and yoga, to engage the girls with alternative\ud physical activities that were potentially available in their community as well as discussion and activities on\ud sexuality, body image and mental health.\ud \ud Knowledge base/ Evidence base: Whilst evaluation of girls' only physical activity programs are not new,\ud research into the impact of an integrated school-based health and physical education curricula are and have\ud implications for future school based approaches.\ud \ud Context of intervention/project/work: The project initially focused on adolescent girls at a small 7-12\ud Secondary College in an isolated community approximately 200 kilometres from the Capital city of Victoria. A\ud grant was awarded to a consortium of local/regional agencies to implement and extend the program over\ud three years. Overwhelmingly the program was conducted by regional and local agencies in conjunction with\ud the local secondary school. It is a partnerships model built on the notion of increasing participation and\ud access for young women whilst building a sustainable program run in partnership with the school and local\ud agencies and services. In 2009 the program was also run in a metropolitan secondary school that had a\ud similar socia-economic background. This paper draws on data from both schools.\ud \ud Methods: This paper reports on qualitative date collected on young women's perceptions of the program, its\ud contribution to their health and wellbeing and the impact of the program on understandings of health related\ud issues of relevance to young women. The data is drawn from focus group data collected from two high\ud schools in the state of Victoria, Australia in 2007, 2008 and 2009. Sixty five girls' in grade 7, 8, 9 and 10\ud participated in the pre and post program interviews.\ud \ud Results and Conclusions: We argue that whilst the data indicates that a girls only program can have a\ud pOSitive impact on aspect of connectedness such as relationships with their peers, reducing bullying\ud behaviour, the data raises some important questions around the adequacy of school-based health education,\ud and the sustainability of approaches designed to be delivered by outside agencies rather than classroom\ud teachers. We argue that whilst single sex health and physical education programs may be necessary for girls\ud to participate and engage fully, the current approach has little impact on traditional notions of gender and\ud body issues.\ud \ud Disclosure of Interest: Centre for Educational Futures and Innovation, Grant Research Support. Victorian Health Promotion Foundation, Grant Research Support

The Escherichia coli glucuronylsynthase promoted synthesis of steroid glucuronides: improved practicality and broader scope

A library of steroid glucuronides was prepared using the glucuronylsynthase derived from Escherichia coliβ-glucuronidase, followed by purification using solid-phase extraction. A representative range of steroid substrates were screened for synthesis on the milligram scale under optimised conditions with conversions dependent on steroid substitution and stereochemistry. Epiandrosterone (3β-hydroxy-5α-androstan-17-one) provided the highest conversion of 90% (84% isolated yield). The previously unreported glucuronide conjugates of methandriol (17α-methylandrost-5-ene-3β,17β-diol), cholest-5-ene-3β,25-diol and the designer steroid trenazone (17β-hydroxyestra-4,9-dien-3-one) were prepared on a multi-milligram scale suitable for characterisation by (1)H and (13)C NMR spectroscopy. The glucuronide conjugate of d5-etiocholanolone (2,2,3,4,4-d5-3α-hydroxy-5β-androstan-17-one), a target developed by the World Anti-Doping Agency as a certified reference material, was also prepared on a milligram scale. The improved E. coli glucuronylsynthase method provides for the rapid synthesis and purification of steroid glucuronides on a scale suitable for a range of analytical applications.Australian Research Council (DP110101235

Repositioning the Catalytic Triad Aspartic Acid of Haloalkane Dehalogenase: Effects on Stability, Kinetics, and Structure

Haloalkane dehalogenase (DhlA) catalyzes the hydrolysis of haloalkanes via an alkyl-enzyme intermediate. The covalent intermediate, which is formed by nucleophilic substitution with Asp124, is hydrolyzed by a water molecule that is activated by His289. The role of Asp260, which is the third member of the catalytic triad, was studied by site-directed mutagenesis. Mutation of Asp260 to asparagine resulted in a catalytically inactive D260N mutant, which demonstrates that the triad acid Asp260 is essential for dehalogenase activity. Furthermore, Asp260 has an important structural role, since the D260N enzyme accumulated mainly in inclusion bodies during expression, and neither substrate nor product could bind in the active-site cavity. Activity for brominated substrates was restored to D260N by replacing Asn148 with an aspartic or glutamic acid. Both double mutants D260N+N148D and D260N+N148E had a 10-fold reduced kcat and 40-fold higher Km values for 1,2-dibromoethane compared to the wild-type enzyme. Pre-steady-state kinetic analysis of the D260N+N148E double mutant showed that the decrease in kcat was mainly caused by a 220-fold reduction of the rate of carbon-bromine bond cleavage and a 10-fold decrease in the rate of hydrolysis of the alkyl-enzyme intermediate. On the other hand, bromide was released 12-fold faster and via a different pathway than in the wild-type enzyme. Molecular modeling of the mutant showed that Glu148 indeed could take over the interaction with His289 and that there was a change in charge distribution in the tunnel region that connects the active site with the solvent. On the basis of primary structure similarity between DhlA and other α/β-hydrolase fold dehalogenases, we propose that a conserved acidic residue at the equivalent position of Asn148 in DhlA is the third catalytic triad residue in the latter enzymes.

Second chances: Investigating athletes’ experiences of talent transfer

Talent transfer initiatives seek to transfer talented, mature individuals from one sport to another. Unfortunately talent transfer initiatives seem to lack an evidence-based direction and a rigorous exploration of the mechanisms underpinning the approach. The purpose of this exploratory study was to identify the factors which successfully transferring athletes cite as facilitative of talent transfer. In contrast to the anthropometric and performance variables that underpin current talent transfer initiatives, participants identified a range of psychobehavioral and environmental factors as key to successful transfer. We argue that further research into the mechanisms of talent transfer is needed in order to provide a strong evidence base for the methodologies employed in these initiatives

The sphere-in-contact model of carbon materials

A sphere-in-contact model is presented that is used to build physical models of carbon materials such as graphite, graphene, carbon nanotubes and fullerene. Unlike other molecular models, these models have correct scale and proportions because the carbon atoms are represented by their atomic radius, in contrast to the more commonly used space-fill models, where carbon atoms are represented by their van der Waals radii. Based on a survey taken among 65 undergraduate chemistry students and 28 PhD/postdoctoral students with a background in molecular modeling, we found misconceptions arising from incorrect visualization of the size and location of the electron density located in carbon materials. Based on analysis of the survey and on a conceptual basis we show that the sphere-in-contact model provides an improved molecular representation of the electron density of carbon materials compared to other molecular models commonly used in science textbooks (i.e., wire-frame, ball-and-stick, space-fill). We therefore suggest that its use in chemistry textbooks along with the ball-and-stick model would significantly enhance the visualization of molecular structures according to their electron density

Characterization of TiO2 nanoparticles in langmuir-blodgett films

In this work we have synthesized TiO2 nanoparticles, using either a sol–gel base catalysed process in the interior of CTAB reversed micelles (TiO2 CTAB sol), or the neutralization of a TiO2/H2SO4 solution in the interior of AOT reversed micelles. From the absorption and emission data of the TiO2 nanoparticles it is possible to conclude that in the sol–gel route there remains alkoxide groups in the structure, originating transitions lower than the energy gap of TiO2 semiconductor. These transitions disappear in the neutralization procedure, where the alkoxide groups are absent in the structure. We have assigned the observed indirect and direct optical transitions according to the anatase band structure. TiO2 Langmuir-Blodgett (LB) films were prepared either by direct deposition of titanium isopropoxide or by deposition of the TiO2 CTAB sol. These films showed photoluminescence, which was attributed to band-gap emission and to surface recombination of defect states

Structural insight into molecular mechanism of poly (ethylene terephthalate) degradation

Plastics, including poly(ethylene terephthalate) (PET), possess many desirable characteristics and thus are widely used in daily life. However, non-biodegradability, once thought to be an advantage offered by plastics, is causing major environmental problem. Recently, a PET-degrading bacterium, Ideonella sakaiensis, was identified and suggested for possible use in degradation and/or recycling of PET. However, the molecular mechanism of PET degradation is not known. Here we report the crystal structure of I. sakaiensis PETase (IsPETase) at 1.5 angstrom resolution. IsPETase has a Ser-His-Asp catalytic triad at its active site and contains an optimal substrate binding site to accommodate four monohydroxyethyl terephthalate (MHET) moieties of PET. Based on structural and site-directed mutagenesis experiments, the detailed process of PET degradation into MHET, terephthalic acid, and ethylene glycol is suggested. Moreover, other PETase candidates potentially having high PET-degrading activities are suggested based on phylogenetic tree analysis of 69 PETase-like proteins

Pt-incorporated anatase TiO2(001) surface for solar cell applications : First-principles density functional theory calculations

First-principles density functional theory calculations were carried out to determine the low energy geometries of anatase TiO$_2$(001) with Pt implants in the sublayers as substitutional and interstitial impurities as well as on the surface in the form of adsorbates. We investigated the effect of such a systematic Pt incorporation in the electronic structure of this surface for isolated and interacting impurities with an emphasis on the reduction in the band gap to visible region. Comprehensive calculations, for 1x1 surface, showed that Pt ions at interstitial cavities result in local segregation, forming metallic wires inside, while substitution for bulk Ti and adsorption drives four strongly dispersed impurity states from valence-bands up in the gap with a narrowing of ~1.5 eV. Hence, such a contiguous Pt incorporation drives anatase into infrared regime. Pt substitution for the surface Ti, on the other hand, metallizes the surface. Systematic trends for 2x2 surface revealed that Pt can be encapsulated inside to form stable structures as a result of strong Pt-O interactions as well as the adsorptional and substitutional cases. Dilute impurities considered for 2x2 surface models exhibit flat-like defect states driven from the valence bands narrowing the energy gap suitable to obtain visible light responsive titania.Comment: 15 pages, 8 figures, 4 tables. to appear on Phys. Rev