Patterns of growth, mortality, and size of the tropical damselfish Acanthochromis polyacanthus across the continental shelf of the Great Barrier Reef

Age-based analyses were used to demonstrate consistent differences in growth between populations of Acanthochromis polyacanthus (Pomacentridae) collected at three distance strata across the continental shelf (inner, mid-, and outer shelf) of the central Great Barrier Reef (three reefs per distance stratum). Fish had significantly greater maximum lengths with increasing distance from shore, but fish from all distances reached approximately the same maximum age, indicating that growth is more rapid for fish found on outer-shelf reefs. Only one fish collected from inner-shelf reefs reached >100 mm SL, whereas 38−67% of fish collected from the outer shelf were >100 mm SL. The largest age class of adult-size fish collected from inner and mid-shelf locations comprised 3−4 year-olds, but shifted to 2-year-olds on outer-shelf reefs. Mortality schedules (Z and S) were similar irrespective of shelf position (inner shelf: 0.51 and 60.0%; mid-shelf: 0.48 and 61.8%; outer shelf: 0.43 and 65.1%, respectively). Age validation of captive fish indicated that growth increments are deposited annually, between the end of winter and early spring. The observed cross-shelf patterns in adult sizes and growth were unlikely to be a result of genetic differences between sample populations because all fish collected showed the same color pattern. It is likely that cross-shelf variation in quality and quantity of food, as well as in turbidity, are factors that contribute to the observed patterns of growth. Similar patterns of cross-shelf mortality indicate that predation rates varied little across the shelf. Our study cautions against pooling demographic parameters on broad spatial scales without consideration of the potential for cross-shelf variabi

Visitor perceptions of captive wildlife tourism in a Western Australian natural setting

Wildlife tourism involves a broad sweep of experiences that includes all of the aspects of the tourism genre with the distinguishing feature of animals as the primary attraction. The uniqueness of Australian wildlife in combination with factors such as remoteness and rarity appear to have provided the ideal context for successful wildlife tourism operations. Barna Mia, located in a large remnant woodland in the central southern wheatbelt of Western Australia, is approximately 165 km southeast of the state's capital, Perth. Dryandra Woodland, the location of Banra Mia consists of a closely grouped and connected cluster of native remnant vegetation blocks. The enclosure is surrounded by electrified, vermin proof fencing to keep feral predators out and the captive fauna in. The results of the visitor survey at Barna Mia suggested the experience provided a great sense of satisfaction amongst respondents. This was both in terms of the overall satisfaction as well as satisfaction with specific parts of the experience. The feeling of being 'in the wild' may have been enhanced by the lack of barriers between visitors and the animals and the absence of constraints on animal movement through the enclosure. Improving the operation of Barna Mia as an attraction in itself and as part of the Dryandra Woodland product may serve to improve its success as an attraction. However, an innately attractive tourism experience cannot work without appropriate integration within the specific wildlife tourism product of Dryandra Woodland, while coordination with tourism on a regional scale is also important

Time and M-theory

We review our recent proposal for a background independent formulation of a holographic theory of quantum gravity. The present review incorporates the necessary background material on geometry of canonical quantum theory, holography and spacetime thermodynamics, Matrix theory, as well as our specific proposal for a dynamical theory of geometric quantum mechanics, as applied to Matrix theory. At the heart of this review is a new analysis of the conceptual problem of time and the closely related and phenomenologically relevant problem of vacuum energy in quantum gravity. We also present a discussion of some observational implications of this new viewpoint on the problem of vacuum energy.Comment: 86 pages, 5 figures, LaTeX, typos fixed, references added, and Sec. 6.2 revised; invited review for Int. J. Mod. Phys.

On the falloff of radiated energy in black hole spacetimes

The goal of much research in relativity is to understand gravitational waves generated by a strong-field dynamical spacetime. Quantities of particular interest for many calculations are the Weyl scalar $\psi_4$, which is simply related to the flux of gravitational waves far from the source, and the flux of energy carried to distant observers, $\dot E$. Conservation laws guarantee that, in asympotically flat spacetimes, $\psi_4 \propto 1/r$ and $\dot E \propto 1/r^2$ as $r \to \infty$. Most calculations extract these quantities at some finite extraction radius. An understanding of finite radius corrections to $\psi_4$ and $\dot E$ allows us to more accurately infer their asymptotic values from a computation. In this paper, we show that, if the final state of the system is a black hole, then the leading correction to $\psi_4$ is ${\cal O}(1/r^3)$, and that to the energy flux is ${\cal O}(1/r^4)$ --- not ${\cal O}(1/r^2)$ and ${\cal O}(1/r^3)$ as one might naively guess. Our argument only relies on the behavior of the curvature scalars for black hole spacetimes. Using black hole perturbation theory, we calculate the corrections to the leading falloff, showing that it is quite easy to correct for finite extraction radius effects.Comment: 5 pages, no figures, accepted to Phys. Rev. D. This version corrects several typos and minor errors in the earlier submissio

Promoting and maintaining health of people with sight loss: A scoping study

This study was undertaken in response to a request by the Thomas Pocklington Trust to identify and explore the following issues: • The needs and concerns regarding immediate risks to health and safety related to sight loss; • Additional risks arising from sight loss for those who are also managing a long term disease; • The difficulties in maintaining and promoting health; • Whether or not health promotion activities and policies sufficiently address perceived needs. Findings pertaining to these objectives have been generated from data collected in Leeds, UK, a city where innovative programming for sight loss has either been planned or is being incorporated into health planning and a review of the literature. Findings related to the last two issues indicate that gaps exist in service provision for maintaining health and emphasise the need for more explicitly targeted health promotion initiatives that could address current weaknesses. - A review of the literature; - Focus group discussions with a range of people who had experienced sight loss; - Interviews with professional practitioners engaged in service provision to this population; - An expert hearing with four professional practitioners, one of whom had sight loss, and two service users with sight loss. Most participants were from the West Yorkshire region and the services described in the study are largely located in Leeds. Evidence from the literature review suggests that people with visual impairment have increased risk of accidents within the home and that ensuing consequences include injuries incurred and decreased confidence. Rates of depression among people who are blind or partially sighted are far higher than in the wider population and the likelihood of depression increases with age, although psycho-social interventions and technological assistance can be successfully implemented to improve quality of life. Sight loss together with other long term health conditions exacerbates the impact of other health conditions and has particularly severe impact on the wellbeing of older people insofar as it may affect their mobility, which in turn increases their risk of falls and depression. The nature and level of support available to people is variable but it is clear that access both to the right information at the right time and to appropriate services is a critical issue. Focus group discussions, interviews and the expert hearing corroborated and extended the themes noted in the literature and discuss the differential impact of different risks to health and the difficulties of coping with these at different times in a person’s life. A simple typology was defined using two dimensions of experience (‘stage of life’ and ‘early/late onset of sight loss’) as a means of organizing findings and providing a means of making further distinctions in interpreting the data. Potentially, this scheme can allow health promotion initiatives to be targeted more effectively to stages at which people with sight loss are more likely to encounter specific difficulties in managing and maintaining their health. There was a clear consensus throughout the study that interventions to meet the needs of people with sight loss must be tailored to meet the specific needs of individuals: people with sight loss are not a homogeneous group and the way in which each person experiences the challenges of sight loss and of managing their health will inevitably vary from person to person. Recommendations generated by this study include: • The scope for more pro-active services and need for closer collaboration between service providers; • The need for provision and promotion of targeted information; • The need for greater awareness of the needs of people with visual impairments among generic service providers; and • Further research that explores the usefulness of the typology with a larger sample more representative of population demographics such as BME communities that are more likely to slip through the cracks of service provision

AGAPEROS: Searching for variable stars in the LMC Bar with the Pixel Method. I. Detection, astrometry and cross-identification

We extend the work developed in previous papers on microlensing with a selection of variable stars. We use the Pixel Method to select variable stars on a set of 2.5 x 10**6 pixel light curves in the LMC Bar presented elsewhere. The previous treatment was done in order to optimise the detection of long timescale variations (larger than a few days) and we further optimise our analysis for the selection of Long Timescale and Long Period Variables (LT&LPV). We choose to perform a selection of variable objects as comprehensive as possible, independent of periodicity and of their position on the colour magnitude diagram. We detail the different thresholds successively applied to the light curves, which allow to produce a catalogue of 632 variable objects. We present a table with the coordinate of each variable, its EROS magnitudes at one epoch and an indicator of blending in both colours, together with a finding chart. A cross-correlation with various catalogues shows that 90% of those variable objects were undetected before, thus enlarging the sample of LT&LPV previously known in this area by a factor of 10. Due to the limitations of both the Pixel Method and the data set, additional data -- namely a longer baseline and near infrared photometry -- are required to further characterise these variable stars, as will be addressed in subsequent papers.Comment: 11 pages with 10 figure