Neon Fine-Structure Line Emission By X-ray Irradiated Protoplanetary Disks

Using a thermal-chemical model for the generic T-Tauri disk of D'Alessio et al. (1999), we estimate the strength of the fine-structure emission lines of NeII and NeIII at 12.81 and 15.55 microns that arise from the warm atmosphere of the disk exposed to hard stellar X-rays. The Ne ions are produced by the absorption of keV X-rays from the K shell of neutral Ne, followed by the Auger ejection of several additional electrons. The recombination cascade of the Ne ions is slow because of weak charge transfer with atomic hydrogen in the case of Ne2+ and by essentially no charge transfer for Ne+. For a distance of 140pc, the 12.81 micron line of Ne II has a flux of 1e-14 erg/cm2s, which should be observable with the Spitzer Infrared Spectrometer and suitable ground based instrumentation. The detection of these fine-structure lines would clearly demonstrate the effects of X-rays on the physical and chemical properties of the disks of young stellar objects and provide a diagnostic of the warm gas in protoplanetary disk atmospheres. They would complement the observed H2 and CO emission by probing vertical heights above the molecular transition layer and larger radial distances that include the location of terrestrial and giant planets.Comment: 24 pages, 5 figure

Effect of torso morphology on maximum hydrodynamic resistance in front crawl swimming

The aim of this study was to determine the influence of torso morphology on maximum instantaneous hydrodynamic resistance in front crawl swimming. Outlines of the torso in the frontal and anteroposterior planes were calculated from photographic images to determine continuous form gradients (m/m) for the anterior, posterior and lateral aspects of the torso. Torso cross-sectional areas at each vertical sample (0.001 m) were used to calculate maximal rate of change in cross-sectional area (m2/m) in the chest-waist and waist-hip segments. During the non-propulsive hand phase in middle-long distance front crawl, kicking propulsion is negligible and therefore the net force is equal to the drag. Drag coefficients were calculated at the instant of maximum horizontal deceleration of centre of mass during the non-propulsive hand phase of 400 m pace front crawl. Maximal rate of change in cross-sectional area (r = 0.44, p = 0.014) and posterior form gradient (r = 0.50, p = 0.006) of the waist-hip torso segment had moderate positive correlations with the maximal drag coefficient. A regression model including these variables explained 41% of the variance (p = 0.001). Indentation at the waist and curvature of the buttocks may result in greater drag force and influence swimming performance

Hospitality and tourism VET in schools: Teachers - the missing ingredient

Students undertaking vocational education and training (VET) in school comprise a rapidly growing component of Australia's VET system, with numbers reaching in excess of 100,000 by the Year 2000, representing around 8% of Australia's vocational students (ANTA, 2002). The inclusion of VET in schools has meant changes to curricula, structures, industry partnerships-and changes in the specialisations of teachers. Finding suitably qualified teachers for classroom delivery of VET has become a pressing issue. The University of Queensland explored the need for a teacher education program for hospitality and tourism teachers, conducting an analysis of the demand for specialist VET teachers, a focus group involving key stakeholders to explore issues surrounding the provision of these teachers, and identified appropriate pathways for their education. This paper reports on the context and background of VET in schools, recommendations of the focus group and the development of a program by the university

Imagine being off-the-grid: Millennials' Perceptions of Digital-Free Travel

The blurred boundaries between home and away facilitated by the ubiquitous connectivity have resulted in restlessness in private life, even on holiday. Disconnecting from technology on holiday could potentially contribute to travellers’ psychological sustainability. This article aims to theorise the perceptions of millennials towards digital-free travel (DFT). We interviewed 17 millennials and applied the Unified Theory of Acceptance and Use of Technology (UTAUT) qualitatively to uncover deep insights into their perceptions. Millennials in the research believe that DFT is beneficial for their well-being, but also have concerns regarding social expectations, technology dependence and environmental support. This article firstly contributes towards the psychological sustainability from the perspective of digital well-being in tourism. Second, the qualitative use of UTAUT in a technology disconnection setting is novel. Finally, the study contributes to the empirical understanding of DFT from the aspect of millennials’ perceptions. The study proposes that mental “away” should be aligned with physical “away” by reducing technology use to achieve psychological sustainability on holiday

Molecular Analyses of Circadian Gene Variants Reveal Sex-Dependent Links Between Depression and Clocks

An extensive literature links circadian irregularities and/or sleep abnormalities to mood disorders. Despite the strong genetic component underlying many mood disorders, however, previous genetic associations between circadian clock gene variants and major depressive disorder (MDD) have been weak. We applied a combined molecular/functional and genetic association approach to circadian gene polymorphisms in sex-stratified populations of control subjects and case subjects suffering from MDD. This approach identified significant sex-dependent associations of common variants of the circadian clock genes hClock, hPer3 and hNpas2 with major depression and demonstrated functional effects of these polymorphisms on the expression or activity of the hCLOCK and hPER3 proteins, respectively. In addition, hCLOCK expression is affected by glucocorticoids, consistent with the sex-dependency of the genetic associations and the modulation of glucocorticoid-mediated stress response, providing a mechanism by which the circadian clock controls outputs that may affect psychiatric disorders. We conclude that genetic polymorphisms in circadian genes (especially hClock and hPer3, where functional assays could be tested) influence risk of developing depression in a sex- and stress-dependent manner. These studies support a genetic connection between circadian disruption and mood disorders, and confirm a key connection between circadian gene variation and major depression

Consumer behaviour in tourism: Concepts, influences and opportunities

Although consumer behaviour (CB) is one of the most researched areas in the field of tourism, few extensive reviews of the body of knowledge in this area exist. This review article examines what we argue are the key concepts, external influences and opportune research contexts in contemporary tourism CB research. Using a narrative review, we examine the CB literature published in three major tourism journals from 2000 to 2012. Of 519 articles identified and reviewed, 191 are included in this article. We examine the development of and scope for future research on nine key concepts, including decision-making, values, motivations, self-concept and personality, expectations, attitudes, perceptions, satisfaction, trust and loyalty. We then examine three important external influences on tourism behaviour, technology, Generation Y and the rise in concern over ethical consumption. Finally, we identify and discuss five research contexts that represent major areas for future scholarship: group and joint decision-making, under-researched segments, cross-cultural issues in emerging markets, emotions and consumer misbehaviour. Our examination of key research gaps is concluded by arguing that the hedonic and affective aspects of CB research in tourism must be brought to bear on the wider CB and marketing literature

Chronic adaptations of lung function in breath-hold diving fishermen

Objectives: The aim of this study was to verify and analyze the existence of chronic adaptations of lung function in freediving fishermen whose occupation is artisanal fishing. Material and Methods: This was a cross-sectional study involving 11 breath-hold diving fishermen and 10 non-breath-hold diving fishermen (control) from the village of Bitupitá in the municipality of Barroquinha (Ceará - Brazil). Anthropometric measurements, chest and abdominal circumferences as well as spirometric and respiratory muscle strength tests were conducted according to the specifications of the American Thoracic Society/European Respiratory Society (ATS/ERS). In order to compare the measured values versus the predicted values, Student t test was used in the case of parametric test and Wilcoxon test in the case of nonparametric test. To compare the inter-group means Student t test was used for parametric test and Mann-Whitney test for the nonparametric one. The level of significance was set at α = 5%. Results: The forced vital capacity (FVC) (4.9±0.6 l vs. 4.3±0.4 l) and forced expiratory volume in 1 s (FEV1) (4.0±0.5 l vs. 3.6±0.3 l) were, respectively, higher in the group of divers compared to the control group (p ≤ 0.05). Furthermore, in the group of free divers, the measured FVC, FEV1 and FEV1/FVC ratios were significantly greater than the predicted ones. No differences were found between the measured respiratory pressures. Conclusions: These results indicate that breath-hold diving seems to produce chronic adaptations of the respiratory system, resulting in elevated lung volumes with no airway obstruction

Functionalized boron nitride membranes with ultrafast solvent transport performance for molecular separation

Pressure-driven, superfast organic solvent filtration membranes have significant practical applications. An excellent filtration membrane should exhibit high selectivity and permeation in aqueous and organic solvents to meet increasing industrial demand. Here, we report an amino functionalized boron nitride (FBN) based filtration membrane with a nanochannel network for molecular separation and permeation. This membrane is highly stable in water and in several organic solvents and shows high transport performance for solvents depending on the membranes' thickness. In addition, the FBN membrane is applicable for solute screening in water as well as in organic solvents. More importantly, the FBN membranes are very stable in acidic, alkaline and oxidative media for up to one month. The fast-flow rate and good separation performance of the FBN membranes can be attributed to their stable networks of nanochannels and thin laminar structure, which provide the membranes with beneficial properties for practical separation and purification processes