Determining the zone of reflection for posterior corneal surface comparison phakometry

Although comparison phakometry has been used by a number of studies to measure posterior corneal shape, these studies have not calculated the size of the posterior corneal zones of reflection they assessed. This paper develops paraxial equations for calculating posterior corneal zones of reflection, based on standard keratometry equations and equivalent mirror theory. For targets used in previous studies, posterior corneal reflection zone sizes were calculated using paraxial equations and using exact ray tracing, assuming spherical and aspheric corneal surfaces. Paraxial methods and exact ray tracing methods give similar estimates for reflection zone sizes less than 2 mm, but for larger zone sizes ray tracing methods should be used.

Chasing Reporters : Intertextuality, Entertainment and Public Knowledge

This paper examines ‘What Have We Learned From Current Affairs This Week?’: a very successful weekly segment from the ABC program The Chaser’s War on Everything. It argues that through its intertextual satire, this regular segment acts not as a traditional news program would in presenting news updates on current events, but as a text which reflects on the way news is reported and how this, in turn, may shape public discourse. While the program has been highly controversial (enduring many a loud call for it to be pulled from air), this form of light entertainment can play an important public service by encouraging citizens to ‘read through’ (Gray, 2006: 104) commercial current affairs’ façade of ‘quality’ journalism.

Determination of optimal preventive maintenance strategy for serial production lines

A Split System Approach (SSA) based methodology is presented to assist in making optimal Preventive Maintenance decisions for serial production lines. The methodology treats a production line as a complex series system with multiple PM actions over multiple intervals. Both risk related cost and maintenance related cost are factored into the methodology as either deterministic or random variables. This SSA based methodology enables Asset Management (AM) decisions to be optimized considering a variety of factors including failure probability, failure cost, maintenance cost, PM performance, and the type of PM strategy. The application of this new methodology and an evaluation of the effects of these factors on PM decisions are demonstrated using an example. The results of this work show that the performance of a PM strategy can be measured by its Total Expected Cost Index (TECI). The optimal PM interval is dependent on TECI, PM performance and types of PM strategies. These factors are interrelated. Generally it was found that a trade-off between reliability and the number of PM actions needs to be made so that one can minimize Total Expected Cost (TEC) for asset maintenance.

In-vehicle avatars to elicit social response and change driving behaviour

Social and psychological theories have provided a plethora of evidence showing that the physical difficulty to express appropriate social interactions between drivers expresses itself in aggression, selfish driving and anti-social behaviour. Therefore there is a need to improve interactions between drivers and allow clearer collective decision making between them. Personal characteristics and the driving situations play strong roles in driver’s aggression. Our approach is centered around the driving situation as opposed to focusing on personality characteristics. It examines aggression and manipulates contextual variables such as driver’s eye contact exchanges. This paper presents a new unobtrusive in-vehicle system that aims at communicating drivers’ intentions, elicit social responses and increasing mutual awareness. It uses eye gaze as a social cue to affect collective decision making with the view to contribute to safe driving. The authors used a driving simulator to design a case control experiment in which eye gaze movements are conveyed with an avatar. Participants were asked to drive through different types of intersections. An avatar representing the head of the other driver was displayed and driver behaviour was analysed. Significant eye gaze pattern difference where observed when an avatar was displayed. Drivers cautiously refer to the avatar when information is required on the intention of others (e.g. when they do not have the right of way). The majority of participants reported the perception of “being looked at”. The number of glances and time spent gazing at the avatar did not indicate an unsafe distraction by standards of in-vehicle device ergonomic design. Avatars were visually consulted primarily in less demanding driving situations, which underlines their non-distractive nature.

Can students with low vision maintain sustained reading rates?

Purpose: Students with low vision may be disadvantaged when compared with their normally sighted peers, as they frequently work at very short working distances and need to use low vision devices. The aim of this study was to examine the sustained reading rates of students with low vision and compare them with their peers with normal vision. The effects of visual acuity, acuity reserve and age on reading rate were also examined. Method: Fifty-six students (10 to 16 years of age), 26 with low vision and 30 with normal vision were required to read text continuously for 30 minutes. Their position in the text was recorded at two-minute intervals. Distance and near visual acuity, working distance, cause of low vision, reading rates and reading habits were recorded. Results: A total of 80.7 per cent of the students with low vision maintained a constant reading rate during the 30 minutes of reading, although they read at approximately half the rate (104 wpm) compared with their normally sighted peers (195 wpm). Only four of the low vision subjects could not complete the reading task. Reading rates increased significantly with acuity reserve and distance and near visual acuity but there was no significant relationship between age and sustained reading rate. Conclusions: The majority of students with low vision were able to maintain appropriate reading rates to cope in integrated educational settings. Surprisingly only relatively few subjects (16 per cent) used their prescribed low vision devices even though the average accommodative demand was 9 D and generally, they revealed a greater dislike of reading compared to students with normal vision.

Is there a need for routine follow-up after primary total hip arthroplasty?

Background: The objective of routine outpatient assessment of well functioning patients after primary total hip arthroplasty (THA) is to detect asymptomatic failure of prostheses to guide recommendations for early intervention. We have observed that the revision of THAs in asymptomatic patients is highly uncommon. We therefore question the need for routine follow-up of patients after THA. Methods: A prospective analysis of an orthopaedic database identified 158 patients who received 177 revision THAs over a 4 year period. A retrospective chart review was conducted. Patient demographics, primary and revision surgery parameters and follow-up information was recorded and cross referenced with AOA NJRR data. Results: 110 THAs in 104 patients (average age 70.4 (SD 9.8 years). There were 70 (63.6%) total, 13 (11.8%) femoral and 27 (24.5%) acetabular revisions. The indications for revision were aseptic loosening (70%), dislocation (8.2%), peri-prosthetic fracture (7.3%), osteolysis (6.4%) and infection (4.5%). Only 4 (3.6%) were asymptomatic revisions. A mean of 5.3 (SD 5.2 and 1.9 (SD 5.3 follow-up appointments were required before revision in patients with and without symptoms, respectively. The average time from the primary to revision surgery was 11.8 (SD 7.23) years. Conclusions: We conclude that patients with prostheses with excellent long term clinical results as validated by Joint Registries, routine follow-up of asymptomatic THA should be questioned and requires further investigation. Based on the work of this study, the current practice of routine follow-up of asymptomatic THA may be excessively costly and unnecessary and a less resource-intensive review method may be more appropriate.

A naturalistic inquiry of registered nurses' perspectives and expectations of psychodynamic therapeutic care in acute psychiatric inpatient facilities

Within contemporary inpatient mental health nursing practice, the psychodynamic model of care considered previously to be central to the nurse-patient relationship now seems a radical concept. It appears to exist only within primary care facilities and public health care practice settings. This naturalistic inquiry aimed to explicate mental health nurses' perspectives and expectations of providing psychodynamic therapeutic care in acute inpatient psychiatric facilities. Ten registered nurses working in acute inpatient mental health facilities were interviewed. Five themes emerged: a career for life, relating in a psychodynamic manner, swimming against the current, adopting a position of difference, and hopeful expectancy.

Robust image hashing using higher order spectral features

Robust image hashing seeks to transform a given input image into a shorter hashed version using a key-dependent non-invertible transform. These image hashes can be used for watermarking, image integrity authentication or image indexing for fast retrieval. This paper introduces a new method of generating image hashes based on extracting Higher Order Spectral features from the Radon projection of an input image. The feature extraction process is non-invertible, non-linear and different hashes can be produced from the same image through the use of random permutations of the input. We show that the transform is robust to typical image transformations such as JPEG compression, noise, scaling, rotation, smoothing and cropping. We evaluate our system using a verification-style framework based on calculating false match, false non-match likelihoods using the publicly available Uncompressed Colour Image database (UCID) of 1320 images. We also compare our results to Swaminathan’s Fourier-Mellin based hashing method with at least 1% EER improvement under noise, scaling and sharpening.

Effects of an acute α-lactalbumin manipulation on mood and food hedonics in high- and low-trait anxiety individuals

Serotonergic hypofunction is associated with a depressive mood state, an increased drive to eat and preference for sweet (SW) foods. High-trait anxiety individuals are characterised by a functional shortage of serotonin during stress, which in turn increases their susceptibility to experience a negative mood and an increased drive for SW foods. The present study examined whether an acute dietary manipulation, intended to increase circulating serotonin levels, alleviated the detrimental effects of a stress-inducing task on subjective appetite and mood sensations, and preference for SW foods in high-trait anxiety individuals. Thirteen high- (eleven females and two males; anxiety scores 45·5 (sd 5·9); BMI 22·9 (sd 3·0)kg/m2) and twelve low- (ten females and two males; anxiety scores 30·4 (sd 4·8); BMI 23·4 (sd 2·5) kg/m2) trait anxiety individuals participated in a placebo-controlled, two-way crossover design. Participants were provided with 40 g α-lactalbumin (LAC; l-tryptophan (Trp):large neutral amino acids (LNAA) ratio of 7·6) and 40 g casein (placebo) (Trp:LNAA ratio of 4·0) in the form of a snack and lunch on two test days. On both the test days, participants completed a stress-inducing task 2 h after the lunch. Mood and appetite were assessed using visual analogue scales. Changes in food hedonics for different taste and nutrient combinations were assessed using a computer task. The results demonstrated that the LAC manipulation did not exert any immediate effects on mood or appetite. However, LAC did have an effect on food hedonics in individuals with high-trait anxiety after acute stress. These individuals expressed a lower liking (P = 0·012) and SW food preference (P = 0·014) after the stressful task when supplemented with LAC.

Socially responsible investment in market downturns : implications for the fiduciary responsibilities of investment fund trustees

This paper investigates whether Socially Responsible Investment (SRI) is more or less sensitive to market downturns than conventional investment, and examines the legal implications for fund managers and trustees. Using a market model methodology, we find that over the past 15 years, the beta risk of SRI, both in Australia and internationally, increased more than that of conventional investment during economic downturns. This implies that companies acting as fund trustees, managed investment schemes and traditional institutional fund managers risk breaching their fiduciary or statutory duties if they go long - or remain long - in SRI funds during market downturns, unless perhaps relevant legislation is reformed. If reform is viewed as desirable, possible reforms could include explicitly overriding the common law to allow all traditional funds to invest in SRI; granting immunity to directors of trustee companies from potential personal liability under sections 197 or 588G et seq of the Corporations Act; allowing companies acting as trustees, managed investment schemes and traditional institutional fund managers and trustees to invest in SRI without triggering a substantial capital gains tax liability through trust resettlement; tax concessions for SRI (eg. introducing a 150% tax deduction or investment allowance for SRI); and allowing SRI sub-funds to obtain “deductible gift recipient” status or the equivalent from relevant taxation authorities. The research is important and original insofar as the assessment of risk in SRIs during market downturns is an area which has hitherto not been subjected to rigorous empirical investigation, despite its serious legal implications.

Quantitative PCR assay of sewage-associated Bacteroides markers to assess sewage pollution in an urban lake in Dhaka, Bangladesh

This paper aimed to assess the magnitude of sewage pollution in an urban lake in Dhaka, Bangladesh by using Quantitative PCR (qPCR) of sewage-associated Bacteroides HF183 markers. PCR was also used for the quantitative detection of ruminant wastewater-associated CF128 markers along with the enumeration of traditional fecal indicator bacteria, namely, enterococci. The number of enterococci in lake water samples ranged from 1.1 x 104 to 1.9 x 105 CFU/100 ml of water. From the 20 water samples tested, 14 (70%) and 7 (35%) were PCR positive for the HF183 and CF128 markers, respectively. The numbers of the HF183 and CF128 markers in lake water samples were 3.9 x 104 to 6.3 × 107 and 9.3 x 103 to 6.3 x 105 genomic units (GU)/100 ml of water, respectively. The high numbers of enterococci and the HF183 markers indicate sewage pollution and potential health risks to those who use the lake water for non-potable purposes such as bathing and washing clothes. This is the first study that investigated the presence of microbial source tracking (MST) markers in Dhaka, Bangladesh where diarrhoeal diseases is one of the major causes of childhood mortality. The molecular assay as used in this study can provide valuable information on the extent of sewage pollution, thus facilitating the development of robust strategies to minimise potential health risks.

An investigation of dose calculation accuracy in intensity-modulated radiotherapy of sites in the head & neck

Knowledge of the accuracy of dose calculations in intensity-modulated radiotherapy of the head and neck is essential for clinical confidence in these highly conformal treatments. High dose gradients are frequently placed very close to critical structures, such as the spinal cord, and good coverage of complex shaped nodal target volumes is important for long term-local control. A phantom study is presented comparing the performance of standard clinical pencil-beam and collapsed-cone dose algorithms to Monte Carlo calculation and three-dimensional gel dosimetry measurement. All calculations and measurements are normalized to the median dose in the primary planning target volume, making this a purely relative study. The phantom simulates tissue, air and bone for a typical neck section and is treated using an inverse-planned 5-field IMRT treatment, similar in character to clinically used class solutions. Results indicate that the pencil-beam algorithm fails to correctly model the relative dose distribution surrounding the air cavity, leading to an overestimate of the target coverage. The collapsed-cone and Monte Carlo results are very similar, indicating that the clinical collapsed-cone algorithm is perfectly sufficient for routine clinical use. The gel measurement shows generally good agreement with the collapsed-cone and Monte Carlo calculated dose, particularly in the spinal cord dose and nodal target coverage, thus giving greater confidence in the use of this class solution.

Encyclopedia contributions: entries A-B

Sections contributed by Jean Sim Agricultural Colleges; p.12 Anzac Park, Townsvile; p.22 Anzac Square, Brisbane; pp.22-23 Benson, Albert Herbert; p.86 Bick, Edward Walter; p.88 Bougainvillea Gardens; p.101 Bowen Park; pp.101-102 Boyd, A.J.; p.103 Brisbane Botanic Gardens; pp.104-105 Bush-house; pp.119-121

Exposure to ultrafine particles and PM2.5 in four Sydney transport modes

Concentrations of ultrafine (<0.1µm) particles (UFPs) and PM2.5 (<2.5µm) were measured whilst commuting along a similar route by train, bus, ferry and automobile in Sydney, Australia. One trip on each transport mode was undertaken during both morning and evening peak hours throughout a working week, for a total of 40 trips. Analyses comprised one-way ANOVA to compare overall (i.e. all trips combined) geometric mean concentrations of both particle fractions measured across transport modes, and assessment of both the correlation between wind speed and individual trip means of UFPs and PM2.5, and the correlation between the two particle fractions. Overall geometric mean concentrations of UFPs and PM2.5 ranged from 2.8 (train) to 8.4 (bus) × 104 particles cm-3 and 22.6 (automobile) to 29.6 (bus) µg m-3, respectively, and a statistically significant difference (p <0.001) between modes was found for both particle fractions. Individual trip geometric mean concentrations were between 9.7 × 103 (train) and 2.2 × 105 (bus) particles cm-3 and 9.5 (train) to 78.7 (train) µg m-3. Estimated commuter exposures were variable, and the highest return trip mean PM2.5 exposure occurred in the ferry mode, whilst the highest UFP exposure occurred during bus trips. The correlation between fractions was generally poor, and in keeping with the duality of particle mass and number emissions in vehicle-dominated urban areas. Wind speed was negatively correlated with, and a generally poor determinant of, UFP and PM2.5 concentrations, suggesting a more significant role for other factors in determining commuter exposure.

Sustainable transportation development : a framework to determine transportation disadvantaged

Urban sprawl combined with low density development causes unsustainable development patterns including accessibility and mobility problems, especially for those who do not have the capacity to own a vehicle or access to quality public transport services. Sustainable transportation development is crucial in order to solve transport disadvantage problems in urban settlements. People who are affected by these problems are referred to as ‘transportation disadvantaged’. Transportation disadvantage is a multi-dimensional problem that combines socio-economics, transportation and spatial characteristics or dimensions. However, a substantial number of transportation disadvantage studies so far only focus on the socio-economic and transportation dimensions, while the latter dimension of transportation disadvantage has been neglected. This chapter investigates the spatial dimension of transportation disadvantage by comparing the travel capabilities of residents and their accessibility levels with land use characteristics. The analysis of the study identifies significant land use characteristics with travel inability, and is useful for identifying the transportation disadvantaged population.