Program Improvement and Practice: In-Service and Pre-Service Student Teaching Reflections

A qualitative study was conducted with graduates (in-service teachers) and pre-service teacher candidates from a traditional elementary education program to explore perceptions of the student teaching process and its impact on teaching philosophy and practices. The program graduates and pre-service teachers described their experience as valuable, but believed their knowledge of pedagogy and classroom management to be deficient. The value of the internship process and implications for program improvement are discussed. Theory without practice is dead, and practice without theory is blind. — Ano

\u27While we can, we will\u27: exploring food choice and dietary behaviour amongst independent older Australians

Aim Burgeoning proportions of populations aged over 65 years impose an increased financial burden upon governments for the provision of associated health and aged-care services. Strategies are therefore required to mitigate service demand through the preservation of good health and independence into old age. Nutrition has been acknowledged as a key factor for realisation of this goal. The objective of the present study was to investigate factors responsible for shaping food shopping, cooking and eating behaviours amongst healthy, independently living Australians aged 60 years and over. Methods Eighteen (5 male, 13 female) independently living residents sourced from three low-care Illawarra Retirement Trust (IRT) lifestyle residential facilities volunteered to take part in the present study. All participants were aged 60 years or more and in relatively good health. Semi-structured focus groups were implemented to explore factors influencing the selection, acquisition and preparation of food. Each session was digitally recorded, transcribed verbatim and subsequently examined using content and thematic analysis. Results Ten sub-themes were identified and grouped into three broader themes: adaptation, psychosocial parameters and food landscape. Findings reflect an active self-determination to retain independence, with a focus on the maintenance of favourable nutritional status. A sense of resourcefulness was evident through the development of strategies to overcome potential barriers to healthy eating. Conclusions Factors that influence the food choices of community-living older Australians are complex and multifactorial, and underpinned by a strong desire for independence and control over personal health outcomes. Studies involving larger, more demographically diverse participant groups are required to elicit socially acceptable strategies that will empower older Australians to sustain their health and independence for the longer term

Probing the Size of Low-Redshift Lyman-alpha Absorbers

The 3C 273 and RX J1230.8+0115 sightlines probe the outskirts of the Virgo Cluster at physical separations between the sightlines of 200-500 h_70 kpc. We present an analysis of HST STIS echelle and FUSE UV spectroscopy of RX J1230.8+0115 in which we detect five Lyman-alpha absorbers at Virgo distances. One of these absorbers is a blend of two strong metal line absorbers coincident in velocity with the highest neutral hydrogen column density absorber in the 3C 273 sightline ~350 h_70 kpc away. The consistency of the metal line column density ratios in the RX J1230.8+0115 sightline allows us to determine the ionization mechanism (photoionization) for these absorbers. While the low signal-to-noise ratio of the FUSE spectrum limits our ability to model the neutral hydrogen column density of these absorbers, we are able to constrain them to be in the range 10^{16-17} cm^-2. The properties of these absorbers are similar to those of the 3C 273 absorber studied by Tripp et al. However, the inferred line-of-sight size for the 3C 273 absorber is only 70 pc, much smaller than those inferred in RX J1230.8+0115, which are 10-30 h_70 kpc. The small sizes of all three absorbers are at odds with the >~350 h_70 kpc minimum transverse size implied by an application of the standard QSO line pairs analysis. On the basis of absorber associations between these two sight lines we conclude that a large-scale structure filament produces a correlated, not contiguous, gaseous structure in this region of the Virgo Supercluster. These data may indicate that we are detecting overdensities in the large scale structure filaments in this region. Alternatively, the presence of a galaxy 71 h_70 kpc from a 3C 273 absorber may indicate that we have probed outflowing, starburst driven shells of gas associated with nearby galaxies.Comment: 13 pages, accepted Ap

Vortex splitting on a planetary scale in the stratosphere by cyclogenesis on a subplanetary scale in the troposphere

It is hypothesized that a splitting of the stratospheric polar vortex and a sudden warming can result when the polar vortex is elongated and a closed cyclonic circulation develops on a subplanetary scale in the troposphere beneath one of its tips. The hypothesis is supported by studying the splitting event in the Southern Hemisphere during spring 2002. Potential vorticity inversion and an inverse modelling technique using the adjoint of a fully nonlinear dynamical model are used to confirm that splitting is sensitive to subplanetary-scale cyclogenesis when it is strong. Examples of stratospheric vortex-splitting events in the Northern Hemisphere are consistent with the hypothesis. The proposed mechanism for splitting contrasts with the commonly accepted one that it is caused by the upward propagation of a planetary wave from the troposphere. It is suggested that the phenomenon is better understood as an example of a vortex interaction rather than as a wave–mean flow interaction

Pickoff and spin-conversion quenchings of ortho-positronium in oxygen

The quenching processes of the thermalized ortho-positronium(o-Ps) on an oxygen molecule have been studied by the positron annihilation age-momentum correlation techinique(AMOC). The Doppler broadening spectrum of the 511 keV gamma-rays from the 2gamma annihilation of o-Ps in O_2 has been measured as a function of the o-Ps age. The rate of the quenching, consisting of the pickoff and the spin-conversion, is estimated from the positron lifetime spectrum. The ratio of the pickoff quenching rate to the spin-conversion rate is deduced from the Doppler broadening of the 511 keV gamma-rays from the annihilation of the o-Ps. The pickoff parameter ^1Z_eff, the effective number of the electrons per molecule which contribute to the pickoff quenching, for O_2 is determined to be 0.6 +- 0.4. The cross-section for the elastic spin-conversion quenching is determined to be (1.16 +- 0.01) * 10^{-19} cm^2.Comment: 4 pages with 5 eps figures, LaTeX2e(revtex4

Audit of the national meal guidelines for home‐delivered and centre‐based meal programs

Objective To evaluate the impact of the National Meal Guidelines on service providers and caterers involved in home‐delivered and centre‐based meal programs in Australia. Methods An anonymous online survey was conducted to explore the uptake of the guidelines by participants and evaluate the impact on their practice. Closed questions were analysed using χ2 and Fisher\u27s exact tests, while open‐ended questions underwent thematic analysis to identify key themes. Results A total of 101 out of 441 participants completed the survey (response rate of 23.0%). Most participants (69%) were currently referring to the guidelines, particularly for nutrition guidelines, menu planning and auditing tools. Key barriers to implementation were cost, supplier compliance issues and lack of staff education. Conclusions The National Meal Guidelines have been successfully implemented in many services around Australia. Further research should investigate their impact on customer satisfaction and external supplier compliance

Do red deer stags (Cervus elaphus) use roar fundamental frequency (F0) to assess rivals?

It is well established that in humans, male voices are disproportionately lower pitched than female voices, and recent studies suggest that this dimorphism in fundamental frequency (F0) results from both intrasexual (male competition) and intersexual (female mate choice) selection for lower pitched voices in men. However, comparative investigations indicate that sexual dimorphism in F0 is not universal in terrestrial mammals. In the highly polygynous and sexually dimorphic Scottish red deer Cervus elaphus scoticus, more successful males give sexually-selected calls (roars) with higher minimum F0s, suggesting that high, rather than low F0s advertise quality in this subspecies. While playback experiments demonstrated that oestrous females prefer higher pitched roars, the potential role of roar F0 in male competition remains untested. Here we examined the response of rutting red deer stags to playbacks of re-synthesized male roars with different median F0s. Our results show that stags’ responses (latencies and durations of attention, vocal and approach responses) were not affected by the F0 of the roar. This suggests that intrasexual selection is unlikely to strongly influence the evolution of roar F0 in Scottish red deer stags, and illustrates how the F0 of terrestrial mammal vocal sexual signals may be subject to different selection pressures across species. Further investigations on species characterized by different F0 profiles are needed to provide a comparative background for evolutionary interpretations of sex differences in mammalian vocalizations

Self-trapping at the liquid vapor critical point

Experiments suggest that localization via self-trapping plays a central role in the behavior of equilibrated low mass particles in both liquids and in supercritical fluids. In the latter case, the behavior is dominated by the liquid-vapor critical point which is difficult to probe, both experimentally and theoretically. Here, for the first time, we present the results of path-integral computations of the characteristics of a self-trapped particle at the critical point of a Lennard-Jones fluid for a positive particle-atom scattering length. We investigate the influence of the range of the particle-atom interaction on trapping properties, and the pick-off decay rate for the case where the particle is ortho-positronium.Comment: 12 pages, 3 figures, revtex4 preprin

Can Age or Height Define Appropriate Thresholds for Transition to Adult Seat Belts? An Analysis of Observed Seat Belt Fit in Children Aged 7–12 Years

This study aimed to investigate associations between demographic, anthropometric and vehicle factors and the fit of adult seat belts in children aged 7–12 years in passenger vehicles. Seat belt fit was assessed by inspection of 7–12-year-old children in their own cars. Logistic regressions examined associations between anthropometric and vehicle factors on achieving good seat belt fit. There were 40 participants included in the analysis, with 16 (40%) having good overall belt fit. The odds of achieving good overall seat belt fit increased by 15% (OR 1.15, 95% CI 1.04–1.27) with every centimeter increase in height and increased by 5% with every one-month increase in age (OR 1.045, 95% CI 1.001–1.10). Controlling for vehicle factors, neither age or height was significantly associated with overall good belt fit, and the discriminatory power of models including these metrics to predict good belt fit was 73% (AUC 0.73, 95% CI 0.55–0.91) and 74% (AUC 0.74, 95% CI 0.58–0.91). The results suggest that taller and older children have a better chance of achieving a good seat belt fit. However, with variations in seat geometry between vehicles, no single simple metric clearly defines an appropriate transition to the adult seat belt