http://nova.newcastle.edu.au/vital/access/services/Feed ${session.getAttribute("locale")} 5 http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12944 In this paper we describe numerical investigations of definite integrals that arise by considering the moments of multi-step uniform random walks in the plane, together with a closely related class of integrals involving the elliptic functions K, K' , E and E' .We find that in many cases such integrals can be “experimentally” evaluated in closed form or that intriguing linear relations exist within a class of similar integrals. Discovering these identities and relations often requires the evaluation of integrals to extreme precision, combined with large-scale runs of the “PSLQ” integer relation algorithm. This paper presents details of the techniques used in these calculations and mentions some of the many difficulties that can arise. 2013-05-22T04:43:20.705Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12943 We shall find a multi-dimensional checkerboard copula of maximum entropy that matches an observed set of grade correlation coefficients. This problem is formulated as the maximization of a concave function on a convex polytope. Under mild constraint qualifications we show that a unique solution exists in the core of the feasible region. The theory of Fenchel duality is used to reformulate the problem as an unconstrained minimization which is well solved numerically using a Newton iteration. Finally, we discuss the numerical calculations for some hypothetical examples and describe how this work can be applied to the modelling and simulation of monthly rainfall. 2013-05-22T04:42:35.791Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12942 We discuss informally two approaches to solving convex and nonconvex feasibility problems – via entropy optimization and via algebraic iterative methods. We shall highlight the advantages and disadvantages of each and give various related applications and limiting examples. While some of the results are very classical, they are not as well-known to practitioners as they should be. A key role is played by the Fenchel conjugate. 2013-05-22T04:41:51.965Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12935 Background: The developmental origins of health and disease is a conceptual framework that helps explain the links between our early life exposures and later health outcomes, and is a burgeoning field of research. In this report, we describe the study protocol used in a prospective cohort of women recruited during pregnancy, with postnatal follow-up of the mothers and offspring. Methods: The Women And Their Children’s Health (WATCH) cohort (n = 180 women) is being conducted at the John Hunter Hospital, Australia (from June 2006). Women attended study visits during pregnancy at 19, 24, 30, and 36 weeks’ gestation. Postnatal follow-up of the women and their offspring occurred at 3-month intervals during the first year after birth and annually thereafter, until age 4 years. Fetal ultrasound scans were performed at each pregnancy visit. Pregnancy and birth data were obtained from hospital records. Data collection has included maternal and child anthropometric, biochemical, dietary, physical activity, socioeconomic, medical, and other variables. Conclusions: The 2 most novel components of our prospective cohort study are (1) the regular and systematic tracking of fetal and child growth and body composition, starting in the second trimester of pregnancy and continuing to age 4 years, and (2) the detailed maternal and child dietary data collection, including biochemical parameters. Detailed cohorts that collect data on the early nutritional, physiological, and social determinants of health are valuable. Despite its relatively small sample size, many hypotheses on developmental origins can be tested or piloted using data collected from the WATCH cohort. 2013-05-22T04:36:40.212Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12934 Folate and vitamin B12 are involved in homocysteine metabolism and are critical to the methylation of DNA. We aimed to assess plasma vitamin B12 (pB12), plasma folate (pFol), and red cell folate (rcFol) in women and their infants during pregnancy and after birth. Maternal biomarkers were tested as predictors of infant biomarkers, including plasma homocysteine (pHcy), at age 6 months. Participants (n = 153) were recruited at the John Hunter Hospital, Australia. Maternal fasting blood samples were collected at 20 and 36 weeks gestation, and at 14 and 27 weeks postpartum. Fifty healthy, term infants provided non-fasting samples at age 6 months. Plasma homocysteine data were available for 16 infants at age 6 months. Maternal pB12 concentrations fell by 16% from 20 to 36 weeks gestation, but had recovered by 14 weeks postpartum. Maternal rcFol concentrations fell by 31% from 20 weeks gestation to 27 weeks postpartum. Infants breastfed at 6 months had lower pB12 (median 159 vs. 402 pmol/L, n = 23 vs. 18, P < 0.01) and folate (median folate z-score -0.58 vs. 0.85, n = 23 vs. 17, P < 0.01), and higher pHcy (median 11.9 vs. 7.3 μmol/L, n = 8 vs. 6, P < 0.01), than those on infant formula. Maternal pregnancy pFol, but not pB12, inversely predicted infant pHcy, after adjustment for the infant’s current pB12 (P = 0.04). Changes in maternal B12 and folate occur during pregnancy and after birth. Infant homocysteine metabolism may be regulated through maternal folate concentrations during pregnancy and postnatal feeding. 2013-05-22T04:35:30.749Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12933 The objective of this study is to describe the fetal phenotype in utero and its associations with maternal pre-pregnancy weight and gestational weight gain. This prospective longitudinal cohort included 179 Australian women with singleton pregnancies. Serial ultrasound measurements were performed at 19, 25, 30 and 36 (±1) weeks gestation and maternal anthropometry were collected concurrently. The ultrasound scans included the standard fetal biometry of head circumference, biparietal diameter, abdominal circumference, and femur length, and body composition at the abdomen and mid-thigh, including fat and lean mass cross-sectional areas. Maternal gestational weight gain was compared to current clinical guidelines. The participants had an average of 3.7 ± 0.8 scans and birth data were available for 165 neonates. Fifty four per cent of the cohort gained weight in excess of current recommendations, according to pre-pregnancy body mass index (BMI). Maternal gestational weight positively predicted fetal abdominal circumference (P 0.029) and lean abdominal mass area (P 0.046) in linear mixed model regression analysis, adjusted for known and potential confounders. At any pre-pregnancy BMI gaining weight above the current recommendations resulted in a larger fetus according to standard biometry, because of significantly larger lean muscle mass at the abdomen (P 0.024) and not due to an increase in fat mass (P 0.463). We have demonstrated the importance of maternal weight gain, independent of pre-pregnancy BMI, to support the growth of a large but lean fetus. Prenatal counselling should focus on achieving a healthy BMI prior to conception so that gestational weight gain restrictions can be minimised. 2013-05-22T04:34:48.790Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12932 Objectives: We aimed to use simple clinical questions to group women and provide their specific rates of miscarriage, preterm delivery, and stillbirth for reference. Further, our purpose was to describe who has experienced particularly low or high rates of each event. Methods: Data were collected as part of the Australian Longitudinal Study on Women's Health, a national prospective cohort. Reproductive histories were obtained from 5806 women aged 31–36 years in 2009, who had self-reported an outcome for one or more pregnancy. Age at first birth, number of live births, smoking status, fertility problems, use of in vitro fertilisation (IVF), education and physical activity were the variables that best separated women into groups for calculating the rates of miscarriage, preterm delivery, and stillbirth. Results: Women reported 10,247 live births, 2544 miscarriages, 1113 preterm deliveries, and 113 stillbirths. Miscarriage was correlated with stillbirth (r = 0.09, P<0.001). The calculable rate of miscarriage ranged from 11.3 to 86.5 miscarriages per 100 live births. Women who had high rates of miscarriage typically had fewer live births, were more likely to smoke and were more likely to have tried unsuccessfully to conceive for ≥12 months. The highest proportion of live preterm delivery (32.2%) occurred in women who had one live birth, had tried unsuccessfully to conceive for ≥12 months, had used IVF, and had 12 years education or equivalent. Women aged 14–19.99 years at their first birth and reported low physical activity had 38.9 stillbirths per 1000 live births, compared to the lowest rate at 5.5 per 1000 live births. Conclusion: Different groups of women experience vastly different rates of each adverse pregnancy event. We have used simple questions and established reference data that will stratify women into low- and high-rate groups, which may be useful in counselling those who have experienced miscarriage, preterm delivery, or stillbirth, plus women with fertility intent. 2013-05-22T04:33:57.873Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12931 Background: In 2009, Australian alcohol guidelines for pregnancy changed from low to no alcohol intake. Previous research found a high proportion of pregnant Australian women drank during pregnancy; however, there has been limited investigation of whether pregnant women comply with 2009 alcohol guidelines. The purpose of this study was to provide an assessment of pregnant women’s compliance with 2009 Australian alcohol guidelines and identify predictors of such compliance, including previous drinking behaviour. Methods: Cross-sectional analysis of prospective data from the 1973–1978 cohort of the Australian Longitudinal Study on Women’s Health was conducted. Women aged 30–36 years who were pregnant at the 2009 survey and had data on alcohol use were included (n = 837). Compliance with 2009 alcohol guidelines for pregnancy was defined as no alcohol intake. Predictors of compliance were analysed using multivariate logistic regression, controlling for area of residence, in three separate models to account for multicollinearity between measures of previous alcohol intake (compliance with 2001 guidelines; frequency and quantity; bingeing). Private health insurance, household income, and illicit drug use were entered into all models and retained if significant. Results: 72% of pregnant women did not comply with the 2009 alcohol guidelines and 82% of these women drank less than seven drinks per week, with no more than one or two drinks per drinking day. The odds of complying with abstinence increased by a factor of 3.48 (95% CI 2.39-5.05) for women who previously complied with the 2001 alcohol guidelines and decreased by a factor of 0.19 (95% CI 0.08-0.66) if household incomes were $36,400 or more. In other models the odds of complying were lower for women who consumed alcohol before pregnancy at least weekly (OR = 0.40, 95% CI 0.25-0.63) or binged (OR ≥ 0.18, 95% CI 0.10-0.31) and were higher for those who abstained (OR = 45.09; 95% CI 8.63-235.49) prior to pregnancy. Conclusion: Most pregnant women did not comply with alcohol guidelines promoting abstinence. Prior alcohol behaviour was the strongest predictor of compliance during pregnancy, suggesting alcohol use should be addressed in women of child-bearing age. The study is limited by the relatively short timeframe between the official introduction of the 2009 guidelines and the date the surveys were sent out. Widespread dissemination of the guidelines may be necessary to help increase guideline compliance by pregnant women. 2013-05-22T04:33:10.434Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:10485 Background: Reduction in a pre-attentive measure of auditory change detection, mismatch negativity (MMN), is one of the most consistent findings in schizophrenia. Recently, our group showed a reduction in MMN to changes in the duration and intensity of background sounds in those within 5 years of illness onset, whereas reduced MMNs to changes in sound frequency were only seen in patients with longer illness duration. In this report, we examine whether reduced MMN, as well as P3a, another index of auditory deviance detection, to duration changes is evident even earlier in the illness, that is, in individuals in the first episode of a psychosis (FEP) and individuals identified as being at ultra-high risk of developing schizophrenia (UHR). Methods: Mismatch negativity and P3a were measured in 30 UHR individuals, 10 FEP individuals, and 20 healthy control subjects to both long (100 msec) and short (50 msec) duration deviant sounds. Results: Mismatch negativity was reduced to both duration deviants not only in the FEP group but also in the UHR group. P3a amplitude was also reduced in the UHR group but at trend level only in FEP. However, MMN and P3a reductions were unrelated in both UHR and FEP groups, suggesting that they reflect distinct deficits. Conclusions: These results suggest that MMN, as well as P3a, to duration deviants are reduced in very early stages of a psychotic illness including those in an at-risk mental state. Both should be considered as potential markers of the prodrome. 2013-05-22T01:52:18.883Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12881 Background: The development and use of Web-based programs for weight loss is increasing rapidly, yet they have rarely been evaluated using randomized controlled trials (RCTs). Interestingly, most people who attempt weight loss use commercially available programs, yet it is very uncommon for commercial programs to be evaluated independently or rigorously. Objective: To compare the efficacy of a standard commercial Web-based weight-loss program (basic) versus an enhanced version of this Web program that provided additional personalized e-feedback and contact from the provider (enhanced) versus a wait-list control group (control) on weight outcomes in overweight and obese adults. Methods: This purely Web-based trial using a closed online user group was an assessor-blinded RCT with participants randomly allocated to the basic or enhanced 12-week Web-based program, based on social cognitive theory, or the control, with body mass index (BMI) as the primary outcome. Results: We enrolled 309 adults (129/309, 41.8% male, BMI mean 32.3, SD 4 kg/m²) with 84.1% (260/309) retention at 12 weeks. Intention-to-treat analysis showed that both intervention groups reduced their BMI compared with the controls (basic: –0.72, SD 1.1 kg/m², enhanced: –1.0, SD 1.4, control: 0.15, SD 0.82; P < .001) and lost significant weight (basic: –2.1, SD 3.3 kg, enhanced: –3.0, SD 4.1, control: 0.4, SD 2.3; P < .001) with changes in waist circumference (basic: –2.0, SD 3.5 cm, enhanced: –3.2, SD 4.7, control: 0.5, SD 3.0; P < .001) and waist-to-height ratio (basic: –0.01, SD 0.02, enhanced: –0.02, SD 0.03, control: 0.0, SD 0.02; P < .001), but no differences were observed between the basic and enhanced groups. The addition of personalized e-feedback and contact provided limited additional benefits compared with the basic program. Conclusions: A commercial Web-based weight-loss program can be efficacious across a range of weight-related outcomes and lifestyle behaviors and achieve clinically important weight loss. Although the provision of additional personalized feedback did not facilitate greater weight loss after 12 weeks, the impact of superior participant retention on longer-term outcomes requires further study. Further research is required to determine the optimal mix of program features that lead to the biggest treatment impact over time. 2013-05-22T01:34:28.920Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12923 This paper examines “Stoneham constants,” namely real numbers of the form α_b,c = Σ_n≥1 1/(cⁿb^cn), for coprime integers b ≥ 2 and c ≥ 2. These are of interest because, according to previous studies, α_b,c is known to be b-normal, meaning that every m-long string of base-b digits appears in the base-b expansion of the constant with precisely the limiting frequency b^-m. So, for example, the constant α_2,3 = Σn≥1 1/(3ⁿ2³ⁿ) is 2-normal. More recently it was established that α_b,c is not bc-normal, so, for example,α_2,3 is provably not 6-normal. In this paper, we extend these findings by showing that α_b,c is not B-normal, where B = b^pc^q r, for integers b and c as above, p, q, r ≥ 1, neither b nor c divide r, and the condition D=c^q/pr^1/p/b^c-1 < 1 is satisfied. It is not known whether or not this is a complete catalog of bases to which α_b,c is nonnormal. We also show that the sum of two B-nonnormal Stoneham constants as defined above, subject to some restrictions, is B-nonnormal. 2013-05-21T05:47:02.433Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12928 Using the results of several extremely large recent computations, we tested positively the normality of a prefix of roughly four trillion hexadecimal digits of π. This result was used by a Poisson process model of normality of π: in this model, it is extraordinarily unlikely that π is not asymptotically normal base 16, given the normality of its initial segment. 2013-05-21T05:41:44.409Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12920 Objectives: To evaluate the effect of a school-based obesity prevention programme on physical self-perception and key physical-activity related cognitions in adolescent boys from disadvantaged secondary schools. A secondary objective was to determine if any psychological changes were associated with improved weight status. Methods: Participants (n= 100, age= 14.3[0.6]) were randomized to the PALS (Physical Activity Leaders) intervention (n= 50) or a control group (n= 50) and assessed at baseline, 3- and 6-month follow up. Measures included BMI, BMI z-score and % body fat (bioelectrical impedance analysis). Students also completed the Children's Physical Self-Perception Profile and a physical activity-related cognitions questionnaire. The findings include secondary data analyses. Results: Relative to the controls, the PALS group significantly increased their physical self worth (p= .01), perceived physical condition (p= .02), resistance training self efficacy (p < .001) and their use of physical activity behavioural strategies (p= .02). Conclusions: A school-based obesity prevention programme that targeted leadership skills improved psychological health in the physical domain in adolescent boys from disadvantaged schools. 2013-05-21T04:21:35.075Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12919 This study evaluated the effects of the Girls Recreational Activity Support Program Using Information Technology (GRASP-IT) intervention. This group randomized controlled trial for older adolescent girls (15 years+) combined face-to-face sessions with the use of a social network website, Facebook. Baseline and follow-up measurements were taken for physical activity (5 day pedometer), height, weight, estimated VO₂max (Queen’s College Step Test), self-efficacy and peer social support. A process evaluation was conducted and included questionnaires and focus groups interviews. Although, the intervention group increased physical activity (mean 1878 steps/day) the difference between groups was not significant (p = 0.11, d = 0.8). BMI, fitness, self-efficacy and peer support all improved for the intervention group, however, changes were not statistically significant between groups. Although participants enjoyed the face-to- face component, engagement with the on-line component was low. Future interventions that utilize Facebook as a medium for increasing physical activity for adolescent girls require additional strategies to improve engagement and compliance. 2013-05-21T04:09:33.548Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12914 In this article, the authors describe the Coast-to-Coast Seminar Series, a pan-Canadian scientific event that has been running since 2005. A short history of the series and a listing of the various stages of its development and related challenges in communicating complex scientific topics to audiences at a number of remote sites is provided. In particular, the authors revisit the original goals of the series and discuss in detail its actual outcomes. They finish by mentioning some present and future applications of their experience as organizers of the series. 2013-05-20T22:41:07.773Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12913 At the present time, IEEE 64-bit floating-point arithmetic is sufficiently accurate for most scientific applications. However, for a rapidly growing body of important scientific computing applications, a higher level of numeric precision is required. Such calculations are facilitated by high-precision software packages that include high-level language translation modules to minimize the conversion effort. This paper presents an overview of recent applications of these techniques and provides some analysis of their numerical requirements. We conclude that high-precision arithmetic facilities are now an indispensable component of a modern large-scale scientific computing environment. 2013-05-20T22:40:11.955Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12912 During the 1970s Brezis and Browder presented a now classical characterization of maximal monotonicity of monotone linear relations in reflexive spaces. In this paper, we extend (and refine) their result to a general Banach space. We also provide an affirmative answer to a problem posed by Phelps and Simons. 2013-05-20T22:38:23.043Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12911 We resolve and further study a sinc integral evaluation, first posed in this Monthly in [1967, p. 1015], which was solved in [1968, p. 914] and withdrawn in [1970, p. 657]. After a short introduction to the problem and its history, we give a general evaluation which we make entirely explicit in the case of the product of three sinc functions. Finally, we exhibit some more general structure of the integrals in question. 2013-05-20T22:37:26.235Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12910 In this paper, we construct maximally monotone operators that are not of Gossez’s dense-type (D) in many nonreflexive spaces. Many of these operators also fail to possess the Brønsted-Rockafellar (BR) property. Using these operators, we show that the partial inf-convolution of two BC–functions will not always be a BC–function. This provides a negative answer to a challenging question posed by Stephen Simons. Among other consequences, we deduce—in a uniform fashion—that every Banach space which contains an isomorphic copy of the James space ensuremathJ or its dual ensuremathJ*, or c ₀ or its dual ℓ¹, admits a non type (D) operator. The existence of non type (D) operators in spaces containing ℓ¹ or c ₀ has been proved recently by Bueno and Svaiter. 2013-05-20T22:35:03.882Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12909 Fathers have not been exclusively targeted in family-based lifestyle programmes. The aim was to determine whether dietary intakes of fathers and children can be improved, following an intervention targeting fathers. Overweight and obese fathers (n=50, 21–65 years, body mass index [mean±standard deviation] 33.3±4.1) and their children (5–12 years) were recruited. Dietary intake was assessed at baseline and 6 months (n=35) by food frequency questionnaire. Linear mixed models determined differences by time. Fathers significantly reduced portion size (P=0.03) but not energy intakes, whereas children reduced energy intakes (kJ) (P=0.02). There is an opportunity to target fathers as to improve child intakes. 2013-05-20T22:32:58.547Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12902 Background: Many Australian children are insufficiently active to accrue health benefits and physical activity (PA) levels are consistently lower among youth of low socio-economic position. PA levels decline dramatically during adolescence and evidence suggests that competency in a range of fundamental movement skills (FMS) may serve as a protective factor against this trend. Methods/design: The Supporting Children’s Outcomes Using Rewards Exercise and Skills (SCORES) intervention is a multi-component PA and FMS intervention for primary schools in low-income communities, which will be evaluated using a group randomized controlled trial. The socio-ecological model provided a framework for the 12-month intervention, which includes the following components: teacher professional learning, student leadership workshops (including leadership accreditation and rewards, e.g., stickers, water bottles), PA policy review, PA equipment packs, parental engagement via newsletters, FMS homework and a parent evening, and community partnerships with local sporting organizations. Outcomes will be assessed at baseline, 6- and 12-months. The primary outcomes are PA (accelerometers), FMS (Test of Gross Motor Development II) and cardiorespiratory fitness (multi-stage fitness test). Secondary outcomes include body mass index [using weight (kg)/height (m²)], perceived competence, physical self-esteem, and resilience. Individual and environmental mediators of behavior change (e.g. social support and enjoyment) will also be assessed. The System for Observing Fitness Instruction Time will be used to assess the impact of the intervention on PA within physical education lessons. Statistical analyses will follow intention-to-treat principles and hypothesized mediators of PA behavior change will be explored. Discussion: SCORES is an innovative primary school-based PA and FMS intervention designed to support students attending schools in low-income communities to be more skilled and active. The findings from the study may be used to guide teacher pre-service education, professional learning and school policy in primary schools. 2013-05-20T03:58:22.970Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12899 Background: The obese-asthma phenotype is not well defined. The aim of this study was to examine both mechanical and inflammatory influences, by comparing lung function with body composition and airway inflammation in overweight and obese asthma. Methods: Overweight and obese (BMI 28-40 kg/m2) adults with asthma (n = 44) completed lung function assessment and underwent full-body dual energy x-ray absorptiometry. Venous blood samples and induced sputum were analysed for inflammatory markers. Results: In females, android and thoracic fat tissue and total body lean tissue were inversely correlated with expiratory reserve volume (ERV). Conversely in males, fat tissue was not correlated with lung function, however there was a positive association between android and thoracic lean tissue and ERV. Lower body (gynoid and leg) lean tissue was positively associated with sputum %neutrophils in females, while leptin was positively associated with android and thoracic fat tissue in males. Conclusions: This study suggests that both body composition and inflammation independently affect lung function, with distinct differences between males and females. Lean tissue exacerbates the obese-asthma phenotype in females and the mechanism responsible for this finding warrants further investigation. 2013-05-20T03:53:09.109Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12898 Background: Limited evidence exists describing the effectiveness of strategies in facilitating the implementation of vegetable and fruit programs by schools on a population wide basis. The aim of this study was to examine the effectiveness of a multi-strategy intervention in increasing the population-wide implementation of vegetable and fruit breaks by primary schools and to determine if intervention effectiveness varied by school characteristics. Methods: A quasi-experimental study was conducted in primary schools in the state of New South Wales, Australia. All primary schools in one region of the state (n = 422) received a multi-strategy intervention. A random sample of schools (n = 406) in the remainder of the state served as comparison schools. The multi-strategy intervention to increase vegetable and fruit breaks involved the development and provision of: program consensus and leadership; staff training; program materials; incentives; follow-up support; and implementation feedback. Comparison schools had access to routine information-based Government support. Data to assess the prevalence of vegetable and fruit breaks were collected by telephone from Principals of the intervention and comparison schools at baseline (2006– 2007) and 11 to 15 months following the commencement of the intervention (2009–2010). GEE analysis was used to examine the change in the prevalence of vegetable and fruit breaks in intervention schools compared to comparison schools. Results: At follow-up, prevalence of vegetable and fruit breaks increased significantly in both intervention (50.3 % to 82.0 %, p < 0.001) and comparison (45.4 % to 60.9 % p < 0.001) schools. The increase in prevalence in intervention schools was significantly larger than among comparison schools (OR 2.36; 95 % CI 1.60-3.49, p <0.001). The effect size was similar between schools regardless of the rurality or socioeconomic status of school location, school size or government or non-government school type. Conclusion: The findings suggest that a multi-strategy intervention can significantly increase the implementation of vegetable and fruit breaks by a large number of Australian primary schools. 2013-05-20T03:49:21.274Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12900 Research Doctorate - Doctor of Philosophy (PhD) 2013-05-20T02:23:58.020Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12405 Evolution and natural selection ensure that specific mechanisms exist for selective airway absorption of inhaled atmospheric molecules. Indeed, nebulized cholinoceptor agonists used in asthma-challenge tests may or may not enter the systemic circulation. We examined the hypothesis that inhaled cholinoceptor agonists have selective access. Six sheep were instrumented under general anesthesia (propofol 5 mg/kg iv, 2-3% isoflurane–oxygen), each with pulsed-Doppler blood flow transducers mounted on the single bronchial artery and sonomicrometer probes mounted on the intrapulmonary third-generation lingula lobe bronchus. Continuous measurements were made of bronchial blood flow (Q_br), Q_br conductance (C_br), bronchial hemicircumference (CIRC_br), and bronchial wall thickness (WALL TH_br) in recovered, standing, awake sheep. Methacholine (MCh; 0.125–2.0 μg/kg iv), at the highest dose, caused a 233% rise in Qbr (P < 0.05) and a 286% rise in C_br (P < 0.05). CIRC_br fell to 90% (P < 0.05); WALL TH_br did not change. In contrast, nebulized MCh (1–32 mg/ml), inhaled through a mask at the highest dose, caused a rise in ventilation and a rise in Qbr proportional to aortic pressure without change in C_br. CIRC_br fell to 91% (P < 0.01), and WALL TH_br did not change. Thus inhaled MCh has access to cholinoceptors of bronchial circumferential smooth muscle to cause airway lumen narrowing but effectively not to those of the systemic bronchovascular circulation. It is speculated that the mechanism is selective neuroparacrine inhibition of muscarinic acetylcholine receptors (M3 bronchovascular cholinoceptors) by prostanoids released by intense MCh activation of epithelial and mucosal cells lining the airway. 2013-05-16T04:49:01.171Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12888 There are limited validated tools available for the assessment of dietary intake in pediatric populations. This report describes a comparative validation study of selected fatty acid intakes in children assessed by food frequency questionnaire (FFQ), compared with erythrocyte membrane fatty acids. Overall, 46 overweight and 47 healthy-weight children aged 5–12 years (mean±SD, 9.1±1.3years, body mass index 20.5±4.0) were recruited; dietary fatty acid intakes assessed by parent report using a 135-item semi-quantitative FFQ, were compared with selected child erythrocyte membrane fatty acids assessed from fasting samples using gas chromatography. Spearman's rank correlation coefficients were calculated between fatty acid intake estimates (% of energy) and erythrocyte membrane concentrations (%mol/mol). Significant correlations were found between dietary and erythrocyte eicosapentanoic acid (EPA) concentration (r=0.24, P<0.05) with a statistical trend for total omega three (∑n-3) fatty acids (r=0.22, P=0.06) and linoleic acid (r=0.32, P=0.07) in the healthy-weight children only. Parental report of selected child fatty acid intakes using an FFQ can be used to provide an estimate of child intake of EPA, but further work is required to quantify this relationship for other fatty acids and in other populations. 2013-05-14T06:36:11.154Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12887 Assessing dietary intake is important in evaluating childhood obesity intervention effectiveness. The purpose of this review was to evaluate the dietary intake methods and reporting in intervention studies that included a dietary component to treat overweight or obese children. A systematic review of studies published in the English language, between 1985 and August 2010 in health databases. The search identified 2,295 papers, of which 335 were retrieved and 31 met the inclusion criteria. Twenty-three studies reported energy intake as an outcome measure, 20 reported macronutrient intakes and 10 studies reported food intake outcomes. The most common dietary method employed was the food diary (n = 13), followed by 24-h recall (n = 5), food frequency questionnaire (FFQ) (n = 4) and dietary questionnaire (n = 4). The quality of the dietary intake methods reporting was rated as ‘poor’ in 15 studies (52%) and only 3 were rated as ‘excellent’. The reporting quality of FFQs tended to be higher than food diaries/recalls. Deficiencies in the quality of dietary intake methods reporting in child obesity studies were identified. Use of a dietary intake methods reporting checklist is recommended. This will enable the quality of dietary intake results to be evaluated, and an increased ability to replicate study methodology by other researchers. 2013-05-14T06:23:34.988Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:11852 Much of the research on the determinants of dietary behavior has been guided by Bandura’s Social Cognitive Theory (SCT), yet few studies have tested the utility of its proposed structural paths. The aim of this paper was to test the capacity of SCT to explain dietary behaviors in a sample of 357 adolescent girls (13.2 ± 0.5 years) from 12 secondary schools located in low-income communities in New South Wales, Australia. Participants completed validated SCT scales assessing nutrition-related self-efficacy, intention, behavioral strategies, family support, situation, outcome expectations, and outcome expectancies. Participants completed a validated food frequency questionnaire, from which, the percentage of total kilojoules from core-foods, non-core foods and saturated fat were calculated. The theoretical models were tested using structural equation modeling in AMOS. The models explained 48–51% and 13–19% of the variance in intention and dietary behavior, respectively. The models provided an adequate fit to the data, and selfefficacy was positively associated with healthy eating and inversely associated with unhealthy eating. However, the pathway from intention to behavior was not statistically significant in any of the models. While this study has demonstrated the utility of SCT constructs to explain behavior in adolescents girls, the proposed structural pathways were not supported. Further study of the role that implementation intentions play in explaining adolescent girls’ dietary behaviors is required. 2013-05-14T06:15:05.179Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12886 Background: Poor childhood nutrition is a more pervasive and insidious risk factor for lifestyle-related chronic disease than childhood obesity. Parents find it difficult to address the reported barriers to optimal child feeding, and to improve child dietary patterns. To impact at the population level, nutrition interventions need to be easy to disseminate, have a broad reach and appeal to parents while overcoming the barriers parents face when trying to improve child feeding behaviours. The Feeding Healthy Food to Kids (FHFK) Randomised Control Trial (RCT) examines the impact of providing low cost, self-directed nutrition and parenting resources to rural parents, on child dietary intake and parent–child feeding practices. Methods/Design: Up to 150 parents of two-to-five year old children will be recruited in five rural Australian towns. Eligible, consenting parents will be randomly allocated to intervention or 12-month wait-list control groups. Intervention group parents will receive an interactive nutrition CD and parenting DVD, and be provided with instructions for optimal resource utilisation. Intervention and control group participants will also receive a generic nutrition and physical activity brochure and a physical activity resource to blind participants to group allocation. Primary outcome measures are dietary intake of vegetables (serves/day), fruit and energy dense nutrient poor foods (serves/day and %Energy). Secondary outcome measures are total energy (kCal), other food groups (serves/day and %Energy), key nutrients (mg/day), child feeding domains and parenting style domains. Analysis of dietary outcome measures, child feeding and parenting domains will be conducted on an intention-to-treat basis and compared at baseline, three and 12 months using the random effects model, using STATA software. Details of the methodological aspects of recruitment, inclusion criteria, randomisation and statistical analysis are described. Discussion: This paper will add to existing research examining child feeding practices and dietary intake of young children, by specifically focusing on the efficacy of an RCT that has the potential to be implemented at a population level. The correlation of the RCT outcomes with parents’ perceptions about child feeding practices and children’s dietary intake of their children in a subsequent qualitative study will further contribute to this emerging area of research. 2013-05-14T05:46:37.648Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12885 Background: Diet quality tools have been developed to assess the adequacy of dietary patterns for predicting future morbidity and mortality. This study describes the development and evaluation of a brief food-based diet quality index for use with children at the individual or population level. The Australian Child and Adolescent Recommended Food Score (ACARFS) was developed to reflect adherence to the Dietary Guidelines for Children and Adolescents in Australia and modelled on the approach of the US Recommended Food Score. Methods: The ACARFS has eight sub-scales and is scored from zero to 73. The diet quality score was evaluated by assessing correlation (Spearman’s correlations) and agreement (weighted κ statistics) between ACARFS scores and nutrient intakes, derived from a food frequency questionnaire in 691 children (mean age 11.0, SD 1.1) in New South Wales, Australia. Nutrient intakes for ACARFS quartiles were compared with the relevant Australian nutrient reference values. Results: ACARFS showed slight to substantial agreement (κ 0.13-0.64) with nutrient intakes, with statistically significant moderate to strong positive correlations with all vitamins, minerals and energy intake (r = 0.42-0.70). ACARFS was not related to BMI.Participants who scored less than the median ACARFS were more likely to have sub-optimal intakes of fibre, folic acid and calcium. Conclusion: ACARFS demonstrated sufficient accuracy for use in future studies evaluating diet quality. Future research on its utility in targeting improvements in the nutritional quality of usual eating habits of children and adolescents is warranted. 2013-05-14T05:45:11.343Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12884 Objective: To evaluate the impact of adherence to public health recommendations on Listeria monocytogenes food safety to limit exposure to potential food sources on micronutrient intakes of pregnant women and whether more frequent consumption of ‘high-risk’ foods increases risk for adverse pregnancy outcomes. Design: A cohort study in women assessing Listeria exposure from an FFQ based on consumption of potential Listeria-containing food sources, the Listeria Food Exposure Score (LFES). Pregnancy status was defined as pregnant, trying to conceive, had a baby within the previous 12 months, or other. Nutrient intakes were compared with Nutrient Reference Values and self-reported pregnancy outcome history three years later. Setting: Australia. Subjects: Women aged 25–30 years (n 7486) participating in the Australian Longitudinal Study on Women’s Health. Results: There were weak positive correlations (r=0.13–0.37, P<0.001) between LFES and all nutrients, with fibre, folate, Fe and vitamin E intakes consistently below the Nutrient Reference Values in every quintile of LFES. Women in the highest quintile of LFES reported 19% more miscarriages (rate ratio =1.19; 95% CI 1.02, 1.38) than those in the lowest quintile, after adjusting for important confounding factors. Conclusions: More frequent consumption of foods potentially containing L. monocytogenes is associated with higher nutrient intakes, but an increased risk of miscarriage. L. monocytogenes pregnancy recommendations require review and should include the list of ‘risky’ food items in addition to low-risk alternatives that would adequately replace nutrient intakes which may be reduced through avoidance strategies. 2013-05-14T05:44:00.051Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12882 Objective: As further understanding is required of what behavioural factors are associated with long-term weight-loss success, the aim of the present study was to determine the prevalence of successful weight loss 15 months post-enrolment in a commercial web-based weight-loss programme and which behavioural factors were associated with success. Design: An online survey was completed 15 months post-enrolment in a commercial web-based weight-loss programme to assess weight-related behaviours and current weight. Participants were classified as successful if they had lost ≥5% of their starting weight after 15 months. Setting: Commercial users of a web-based weight-loss programme. Subjects: Participants enrolled in the commercial programme between August 2007 and May 2008. Six hundred and seventy-seven participants completed the survey. Results: The median (interquartile range) weight change was -2.7 (-8.2, 1.6) % of enrolment weight, with 37% achieving ≥5% weight loss. Multivariate logistic regression analysis found success was associated with frequency of weight self-monitoring, higher dietary restraint score, lower emotional eating score, not skipping meals, not keeping snack foods in the house and eating takeaway foods less frequently. Conclusions: The findings suggest that individuals trying to achieve or maintain ≥5% weight loss should be advised to regularly weigh themselves, avoid skipping meals or keeping snack foods in the house, limit the frequency of takeaway food consumption, manage emotional eating and strengthen dietary restraint. Strategies to assist individuals make these changes to behaviour should be incorporated within obesity treatments to improve the likelihood of successful weight loss in the long term. 2013-05-14T05:42:54.888Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12880 Nutrition during pregnancy can induce alterations in offspring phenotype. Maternal ratio of protein to non-protein (P:NP) energy has been linked to variations in offspring body composition and adult risk of metabolic disease. This study describes the dietary patterns of pregnant women by tertiles of the P:NP ratio and compares diet to Australian recommendations. Data are from 179 Australian women enrolled in the Women and Their Children’s Health Study. Diet was assessed using a validated 74-item food frequency questionnaire. Food group servings and nutrient intakes were compared to the Australian Guide to Healthy Eating and Australian Nutrient Reference Values. Higher maternal P:NP tertile was positively associated with calcium (P = 0.003), zinc (P = 0.001) and servings of dairy (P = 0.001) and meat (P = 0.001) food groups, and inversely associated with the energy dense, nutrient poor non-core (P = 0.003) food group. Micronutrient intakes were optimized with intermediate protein (18%E–20%E), intermediate fat (28%E–30%E) and intermediate carbohydrate (50%E–54%E) intakes, as indicated in tertile two. Results suggest a moderate protein intake may support pregnant women to consume the largest variety of nutrients across all food groups. 2013-05-14T01:47:19.023Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12857 This paper gives an empirical investigation of some tests of goodness of fit for the inverse Gaussian distribution. 2013-05-09T03:25:21.921Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12424 We investigate the cogrowth and distribution of geodesics in R. Thompson's group F. 2013-05-07T03:33:09.392Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12535 Data from the HMRI Consumer Registry Survey will be used to determine the proportion of chronic disease out-patients who are willing to be contacted about future research and quantify how frequently they would be willing to be contacted about potential research projects. Support persons, defined as individuals who provide daily care or assistance to a patient, can also complete the Consumer Registry Survey. Survey items, including object type: Demographic information, disease-specific information (such as diagnosis, time to surgery), preferences for research participation, and contact details. Survey item types include text fields and multiple choice (radiobutton). The maximum number of items an individual can answer is 32; the minimum is 12. Survey domains or latent variables: There are no domains or latent variables. Psychometric analysis or development information: This survey does not require psychometric analysis. It was developed using iterative review involving health service researchers, HMRI key stakeholders, and community members. Data collection methods, including time frame: Data will be collected using iPad technology with the assistance of trained HMRI research support persons. Eligible participants are approached by research support persons while waiting for their appointment in a chronic disease or surgical out-patient clinic. The survey takes approximately 7 minutes to complete. Data collection began in December 2012. Inclusion criteria and sample size: To be eligible, participants must be: over the age of 18 years; be attending a neurology, cardiology, respiratory, surgical, or medical oncology out-patient clinic; understand English; and have attended the clinic at least once prior to enrollment. A total of 1400 participants are included across all out-patient clinics. This sample size will be composed of: 400 medical oncology, 400 surgical, 200 neurology, 200 cardiology, and 200 respiratory. Demographic description of participants: Not available at this time. Any anticipated secondary data analysis: None 2013-05-02T23:29:08.342Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12839 Aim: To record student feedback on a placement programme where students offered oral health assessments and oral hygiene advice to older people living in Residential Aged Care Facilities (RACFs) on the NSW Central Coast, Australia. Methodology: Final year Bachelor of Oral Health students from the University of Newcastle were asked to complete pre and post placement questionnaires relating to knowledge, willingness and ability to assess oral health needs and deliver oral health advice to RACF residents and staff. Results: Sixty seven students attended the placement programme, 50 (77%) completed the pre- and post- placement questionnaires. Mean Likert scores showed that students reported knowledge to assess the oral health needs of residents with Alzheimer’s significantly improved post placement (P<0.0001) as did their knowledge of how to produce oral hygiene educational material for RACF staff (P<0.0001). An improvement in ability to assess the oral health needs of residents with dementia was significant (P<0.01) and students reported feeling less nervous following the placement (P<0.0001). Student willingness to provide oral hygiene instruction, routinely work with older people in RACFs and speak confidently to RACF staff did not change as a result of the placement. Conclusions: The placement programme enhanced students’ reported knowledge and ability to assess oral health needs and provide oral hygiene instruction for older residents including those with Alzheimer’s and dementia. However, other aspects of the programme had no positive impact and require further research. 2013-05-02T03:39:24.917Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12810 This paper addresses the unconscious dimension as articulated in Carl Jung’s depth psychology and in Gilles Deleuze’s philosophy. Jung’s theory of the archetypes and Deleuze’s pedagogy of the concept are two complementary resources that posit individuation as the goal of human development and self-education in practice. The paper asserts that educational theory should explore the role of the unconscious in learning, especially with regard to adult edu ation in the process of learning from life-experiences. The integration of the unconscious into consciousness becomes a constitutive part of subject-formation and self-knowledge, which in turn serves as a basis for experiential self-education. 2013-04-29T05:36:59.615Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12799 This paper tackles a generalization of the weight constrained shortest path problem (WCSPP) in a directed network with replenishment arcs that reset the accumulated weight along the path to zero. Such situations arise, for example, in airline crew pairing applications, where the weight represents duty hours, and replenishment arcs represent crew overnight rests; and also in aircraft routing, where the weight represents time elapsed, or flight time, and replenishment arcs represent maintenance events. In this paper, we review the weight constrained shortest path problem with replenishment (WCSPP-R), develop preprocessing methods, extend existing WCSPP algorithms, and present new algorithms that exploit the inter-replenishment path structure. We present the results of computational experiments investigating the benefits of preprocessing and comparing several variants of each algorithm, on both randomly generated data, and data derived from airline crew scheduling applications. 2013-04-26T01:04:31.888Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12805 In the Platonic work Alcibiades I, a divinely guided Socrates adopts the guise of a lover in order to divert Alcibiades from an unthinking political career. The contributors to this carefully focussed volume cover aspects of the background to the work; its arguments and the philosophical issues it raises; its relationship to other Platonic texts, and its subsequent history up to the time of the Neoplatonists. Despite its ancient prominence, the authorship of Alcibiades I is still unsettled; the essays and two appendices, one historical and one stylometric, come together to suggest answers to this tantalising question. 2013-04-26T00:59:30.446Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12804 Alcibiades is, at once, an historical figure and an archetypal individual. Also, in an anthropological sense and in terms of traditions of thought, Alcibiades is a truly remarkable, individuated moment in history. Alcibiades the historical personage and philosophical character-as-actor has become a source for historical and philosophical memories, that is, a human gathering place, a focus, reference and a trans-historical persona for the passages of history and intellect - a place where singular and collective human actions and behaviours matter and where particular and general social forces remain; contentiously in play. With the classical world of the Athenian empire immediately behind the philosophical stage and dramatically present in the foreground of the Alcibiades I, and with the Spartan world still presenting intellectual and social puzzles, who better than the exiled, prodigal Athenian son, Alcibiades and Socrates to discuss the deep waters -the social anthropology of a once-real world and its strikingly individuated conduct. Significantly, these modes of human conduct must be clearly seen as situated within the broad agonistic context of Hellenic and Mediterr!ilnean civilisations. These 'particular' and 'general' ideas and arguments are swept by Mediterranean scenes and characters. 2013-04-26T00:58:36.323Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12800 We consider a knapsack problem with precedence constraints imposed on pairs of items, known as the precedence constrained knapsack problem (PCKP). This problem has applications in manufacturing and mining, and also appears as a subproblem in decomposition techniques for network design and related problems. We present a new approach for determining facets of the PCKP polyhedron based on clique inequalities. A comparison with existing techniques, that lift knapsack cover inequalities for the PCKP, is also presented. It is shown that the clique-based approach generates facets that cannot be found through the existing cover-based approaches, and that the addition of clique-based inequalities for the PCKP can be computationally beneficial, for both PCKP instances arising in real applications, and applications in which PCKP appears as an embedded structure. 2013-04-19T04:49:32.328Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12786 The feasibility pump is a recent, highly successful heuristic for general mixed integer linear programming problems. We show that the feasibility pump heuristic can be interpreted as a discrete version of the proximal point algorithm. In doing so, we extend and generalize some of the fundamental results in this area to provide new supporting theory. We show that feasibility pump algorithms implicitly minimize a weighted combination of the objective and a term which penalizes lack of integrality. This function has many local minima, some of which correspond to feasible integral solutions; the feasibility pump’s use of random restarts can be viewed as seeking to escape these local minima when they are not feasible integral solutions. This interpretation suggests alternative ways of incorporating restarts, one of which is the application of cutting planes. Numerical experiments with cutting planes show encouraging results on standard test libraries. 2013-04-19T01:06:16.425Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12717 Coal remains the most important energy source for power generation, providing 37% of the world's electricity. As the global population grows, and as living standards improve in the developing world, an international demand for energy is increasing at a rapid rate. Coal is still the most abundant, widely distributed, safe, and economical fossil fuel available to meet this escalating energy demand. 2013-04-19T00:06:25.024Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12775 Noncardiac chest pain (NCCP) is very prevalent in the community. Although mortality remains low, morbidity and the financial implications are high. Women, especially those of middle age, should be thoroughly investigated as per current guidelines for coronary artery disease before labeling their chest pain as NCCP. Gastroesophageal reflux disease is the most common cause of NCCP; however other esophageal pathology including esophageal hypersensitivity, neuromuscular disease and eosinophilic esophagitis may also cause NCCP. Proton pump inhibitors are commonly used initially to manage NCCP, although patients who do not respond to this therapy require further investigation and differing treatment regimes. This article will focus on current knowledge regarding GI tract-related NCCP management strategies. 2013-04-16T05:17:12.810Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12781 We evaluated the effect of aerosolized fluticasone therapy on symptomatic dysphagia and histologic eosinophilia in adults with eosinophilic esophagitis (EoE). We performed a double-blind, randomized, placebo-controlled trial of fluticasone in 42 adult patients with a new diagnosis of EoE (30 men; mean age, 37.5 y). Participants were assigned randomly to groups that swallowed 880 μg of aerosolized fluticasone twice daily (n = 21), or took a placebo inhaler twice daily (n = 15) for 6 weeks. End points of the study were symptomatic and histologic response. A complete histologic response (>90% decrease in mean eosinophil count) was observed in 11 of 15 subjects who received 6 weeks of fluticasone (62%), compared with none of the 15 subjects who received placebo (P < .001), based on intention-to-treat analysis; histologic responses were observed in 68% of subjects who received fluticasone (13 of 19) compared with none of those who received placebo (0 of 15) by per-protocol analysis (P < .001). Intracellular staining for eosinophil-derived neurotoxin was reduced in 81% of subjects who received fluticasone (13 of 16) compared with 8% who received placebo (1 of 13) (P < .001). Dysphagia was reduced in 57% of subjects who received fluticasone (12 of 21) compared with 33% who received placebo (7 of 21) (P = .22) by intention-to-treat analysis; dysphagia was reduced in 63% of patients who received fluticasone (12 of 19) and 47% of those who received placebo (7 of 15) (P = .49) based on per-protocol analysis. Esophageal candidiasis developed in 26% of subjects who received fluticasone (5 of 19), but in none of the subjects in the placebo group (P = .05). Aerosolized, swallowed fluticasone leads to a histologic but not a symptomatic response in adults with EoE. 2013-04-16T05:09:47.596Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12780 Esophageal adenocarcinoma (EA) is increasingly common among patients with Barrett's esophagus (BE). We aimed to provide consensus recommendations based on the medical literature that clinicians could use to manage patients with BE and low-grade dysplasia, high-grade dysplasia (HGD), or early-stage EA. We performed an international, multidisciplinary, systematic, evidence-based review of different management strategies for patients with BE and dysplasia or early-stage EA. We used a Delphi process to develop consensus statements. The results of literature searches were screened using a unique, interactive, Web-based data-sifting platform; we used 11,904 papers to inform the choice of statements selected. An a priori threshold of 80% agreement was used to establish consensus for each statement. Eighty-one of the 91 statements achieved consensus despite generally low quality of evidence, including 8 clinical statements: (1) specimens from endoscopic resection are better than biopsies for staging lesions, (2) it is important to carefully map the size of the dysplastic areas, (3) patients that receive ablative or surgical therapy require endoscopic follow-up, (4) high-resolution endoscopy is necessary for accurate diagnosis, (5) endoscopic therapy for HGD is preferred to surveillance, (6) endoscopic therapy for HGD is preferred to surgery, (7) the combination of endoscopic resection and radiofrequency ablation is the most effective therapy, and (8) after endoscopic removal of lesions from patients with HGD, all areas of BE should be ablated. We developed a data-sifting platform and used the Delphi process to create evidence-based consensus statements for the management of patients with BE and early-stage EA. This approach identified important clinical features of the diseases and areas for future studies. 2013-04-16T05:08:44.109Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12779 Background: Limited published data exist on the associated comorbid conditions with functional dyspepsia (FD). Aims: This study aimed to assess the prevalence, services, and costs related to comorbid conditions associated with FD and the risk of having FD for each comorbid condition. Methods: A retrospective database analysis was undertaken using payroll data and adjudicated claims from January 1, 2001, through December 31, 2004 among >300,000 employees. Employees with FD were compared to propensity-score-matched employees without FD (controls). Outcome measures included the prevalence, costs, and utilization of health services for comorbid conditions as defined by the Agency for Healthcare Research and Quality (AHRQ) and the odds ratios of having FD from a multivariate model. Results: FD employees (N = 1,669) and a 50:1 matched control cohort (N = 83,450) were compared. Compared to matched controls, FD employees were more likely to have all major diagnostic categories. Moreover, 199/261 of the AHRQ’s specific categories were more common in the FD cohort. Annual medical costs for the FD cohort were greater than for controls in 155/261 (59%) specific categories and significantly greater (P ≤ 0.05) in 76 categories (29%). Similarly, services were greater for 179/261 (69%) specific categories and significantly greater (P ≤ 0.05) in 110 categories (42%). In a multivariate model, esophageal disorders, gastritis and duodenitis, and abdominal pain were the most associated with having FD (odds ratios 3.8, 3.7, and 3.6, respectively). Only hypertension complications and disorders of the teeth and jaw were significantly negatively associated with FD.Conclusion: There is unexplained excess comorbidity associated with FD which may be a major determining factor for excess healthcare services and costs. 2013-04-16T05:07:52.215Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12778 Background & Aims: The prevalence of chronic constipation (CC) has been reported to be as high as 20% in the general population, but little is known about its natural history. We estimated the natural history of CC and characterized features of persistent CC and nonpersistent CC, compared with individuals without constipation. Methods: In a prospective cohort study, we analyzed data collected from multiple, validated surveys (minimum of 2) of 2853 randomly selected subjects, over a 20-year period (median, 11.6 years). Based on responses, subjects were characterized as having persistent CC, nonpersistent CC, or no constipation. We assessed the association between constipation status and potential risk factors using logistic regression models, adjusting for age and sex. Results: Of the respondents, 84 had persistent CC (3%), 605 had nonpersistent CC (21%), and 2164 had no symptoms of constipation (76%). High scores from the somatic symptom checklist (odds ratio [OR] = 2.1; 95% confidence interval [CI], 1.3–3.4) and frequent doctor visits (OR = 2.0; 95% CI, 1.0–3.8) were significantly associated with persistent CC, compared with subjects with no constipation symptoms. The only factor that differed was increased use of laxatives or fiber among subjects with persistent CC (OR = 3.0; 95% CI, 1.9–4.9). Conclusions: The prevalence of constipation might be exaggerated—the proportion of the population with persistent CC is low (3%). Patients with persistent and nonpersistent CC have similar clinical characteristics, although individuals with persistent CC use more laxatives or fiber. CC therefore appears and disappears among certain patients, but we do not have enough information to identify these individuals in advance. 2013-04-16T05:06:47.349Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12777 Objectives: In patients with diabetes mellitus (DM) and upper gastrointestinal symptoms, a diagnosis of diabetic gastroparesis is often considered, but population-based data on the epidemiology of diabetic gastroparesis are lacking. We aimed to estimate the frequency of and risk factors for gastroparesis among community subjects with DM. Methods: In this population-based, historical cohort study, the medical records linkage system of the Rochester Epidemiology Project was used to identify 227 Olmsted County, MN residents with type 1 DM in 1995, a random sample of 360 residents with type 2 DM, and an age- and sex-stratified random sample of 639 nondiabetic residents. Using defined diagnostic criteria, we estimated the subsequent risk of developing gastroparesis in each group through 2006. The risk in DM, compared with frequency-matched community controls, was assessed by Cox proportional hazards modeling. Results: The cumulative proportions developing gastroparesis over a 10-year time period were 5.2% in type 1 DM, 1.0% in type 2 DM, and 0.2% in controls. The age- and gender-adjusted hazard ratios (HRs) for gastroparesis (relative to controls) was 33 (95% confidence interval (CI): 4.0, 274) in type 1 DM and 7.5 (95% CI: 0.8, 68) in type 2 DM. The risk of gastroparesis in type 1 DM was significantly greater than in type 2 DM (HR: 4.4 (1.1, 17)). Heartburn (HR: 6.6 (1.7, 25)) at baseline was associated with diabetic gastroparesis in type 1 DM. Conclusions: Gastroparesis is relatively uncommon in patients with DM, although an increased risk for gastroparesis was observed in type 1 DM. 2013-04-16T05:05:53.857Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12776 Objective: There are few prospective studies of the prevalence of colonic neoplasia in the normal population. In order to properly evaluate screening-protocols for colorectal cancer in risk groups (e.g., older subjects or those with a family history), it is essential to know the prevalence of adenomas and cancer in the normal population. Methods: A prospective population-based colonoscopy study on 745 individuals born in Sweden aged 19–70 years was conducted (mean age 51.1 years). All polyps seen were retrieved and examined. Results: Out of the 745 individuals 27% had polyps, regardless of kind. Adenomas were found in 10% of the individuals and finding of adenomas was positively correlated to higher age. Men had adenomas in 15% and women in 6% of the cases. Women had a right-sided dominance of adenomas. Hyperplastic polyps were seen in 21% of the individuals. The presence of hyperplastic polyps was significantly positively correlated to the presence of adenomas. Advanced adenomas were seen in 2.8% of the study participants, but no cancers were detected. Conclusion: One in 10 healthy subjects had an adenoma but advanced adenomas were uncommon. Men and women have a different adenoma prevalence and localization. The results provide baseline European data for evaluating colonoscopy screening-protocols for colorectal cancer risk groups, and the findings may have implications for colon cancer screening in the normal, otherwise-healthy population. 2013-04-16T05:04:30.279Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12774 Fecal incontinence is a common condition, which leads to impaired quality of life and huge financial cost at an individual and societal level. Recent studies have identified novel and potentially modifiable risk factors. Newer diagnostic modalities are giving more detailed information about underlying disorders, helping to implement targeted treatment. Many therapeutic options exist, and newer treatments are changing outcomes. This article will review recent developments in mechanisms, diagnosis, and treatment of fecal incontinence. Potentially modifiable risk factors have recently been identified, and should translate to changes in clinical practice and hopefully patient outcomes. These include diarrhea, smoking, and dietary fiber. Advances have been made in anatomical and physiological testing of the anorectum and this may assist in clarifying the diagnosis and guiding management. The long-term benefit of biofeedback has been questioned but patient selection may be key. Novel pharmacological therapies (e.g., clonidine) and minimally invasive surgical procedures are changing outcomes in well selected patients. The development of a magnetic anal sphincter may add a new management alternative in patients who are refractory to conservative management. Fecal incontinence remains a clinical challenge. Only a minority of persons with fecal incontinence seek treatment, but for those who do, improved understanding of risk factors coupled with diagnostic techniques and treatments are improving outcomes. 2013-04-16T05:02:43.590Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12773 The current health-care environment is demanding evidence-based medicine that relies on clinical trials as the basis for decisions. Clinician investigators are more often finding that they are personally responsible for coordinating large, multisite trials. We present strategies for successful implementation and management of multisite clinical trials and knowledge gained through an international, multisite randomized clinical trial. Topics include team composition, regulatory requirements, study organization and governance, communication strategies, recruitment and retention efforts, budget, technology transfer, and publication. 2013-04-16T05:01:48.613Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12772 Chronic obstructive pulmonary disease (COPD) and inflammatory bowel diseases (IBDs) are chronic inflammatory diseases of mucosal tissues that affect the respiratory and gastrointestinal tracts, respectively. They share many similarities in epidemiological and clinical characteristics, as well as in inflammatory pathologies. Importantly, both conditions are accompanied by systemic comorbidities that are largely overlooked in both basic and clinical research. Therefore, consideration of these complications may maximize the efficacy of prevention and treatment approaches. Here, we examine both the intestinal involvement in COPD and the pulmonary manifestations of IBD. We also review the evidence for inflammatory organ cross-talk that may drive these associations, and discuss the current frontiers of research into these issues. 2013-04-16T05:00:44.845Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12771 Background: Quality of life is impaired in some people with IBS, but the level of symptoms that may drive this impairment is unclear. Aims: We aimed to identify whether current frequency and severity cut-offs for IBS-type symptoms are associated with a clinically meaningful impairment of quality of life in the community. Methods: People who met modified Rome III criteria for IBS (n = 201) and controls (n = 1,904) were assessed. Frequency of IBS symptoms was grouped a priori into ‘less frequent’ (not at all and sometimes) and ‘more’ frequent (often, very often and almost always). Severity of abdominal pain was grouped into ‘mild’ (very mild and mild) and severe (moderate, severe and very severe). Mental and physical functioning was measured using the valid SF-12, with ‘normal’ functioning (defined as a score of >43 and >48) and ‘impaired’ functioning (defined as a score of ≤43 and ≤48), respectively. Psychological variables were assessed via valid self-report. Results: Having ‘more’ versus ‘less’ severe abdominal pain (OR = 9.41; 95% CI 1.17–75.43, P = 0.03) and ‘more’ versus ‘less’ frequent diarrhoea (OR = 2.19; 95% CI 1.13–4.26, P = 0.02) along with increasing age (OR = 1.03; 95% CI 1.01–1.05, P = 0.003) were significant independent predictors of having impairment in physical functioning. In terms of psychological factors, having higher levels of depression (OR = 1.61; 95% CI 1.36–1.91) and somatic distress (OR = 1.17; 95% CI 1.09–1.27) were independently associated with mental and physical impairment, respectively. Conclusion: The current frequency and severity threshold cut-offs for IBS symptoms in the Rome III criteria are associated with a clinically meaningful impairment of quality of life in community subjects with IBS. 2013-04-16T04:59:44.628Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12770 Objective: Psychological factors are known to be associated with functional gastrointestinal disorders (FGIDs) including irritable bowel syndrome (IBS) and functional dyspepsia (FD). No prospective studies have evaluated whether it is the brain (eg, via anxiety) that drives gut symptoms, or whether gut dysfunction precipitates the central nervous system features such as anxiety. In a 12-year longitudinal, prospective, population-based study, we aimed to determine the directionality of the brain–gut mechanism in FGIDs. Design: Participants (n=1775) were a random population sample from Australia who responded to a survey on FGIDs in 1997 and agreed to be contacted for future research; 1002 completed the 12-year follow-up survey (response rate =60%), with 217, 82 and 45 people meeting Rome II for new onset FGIDs, IBS and FD, respectively. Anxiety and depression were measured using the Delusions Symptom States Inventory at baseline and follow-up. Results: Among people free of a FGID at baseline, higher levels of anxiety (OR 1.11; 95% CI 1.03 to 1.19, p=0.006) but not depression at baseline was a significant independent predictor of developing new onset FGIDs 12 years later. Among people who did not have elevated levels of anxiety and depression at baseline, those with a FGID at baseline had significantly higher levels of anxiety and depression at follow-up (mean difference coefficient 0.76, p<0.001 and 0.30, p=0.01 for anxiety and depression, respectively). In IBS higher levels of anxiety and depression at baseline were predictive of IBS at follow-up, while only depression was predictive of FD at follow-up. Conclusions: The central nervous system and gut interact bidirectionally in FGIDs. 2013-04-16T04:58:28.894Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12769 Background & Aims: The rapid response to topical corticosteroids makes it hard to implicate fibrosis as the cause of dysphagia in patients with eosinophilic esophagitis (EoE). We examined surrogates of esophageal expansion using minimal and maximal esophageal diameter (EDmin and EDmax) in barium swallow examinations. Methods: Eleven patients evaluated at Mayo Clinic, Rochester (8 female, median age 40, median diagnosis 36 months, median symptom duration 132 months) underwent barium esophagrams to determine EDmin and EDmax before and after 6 weeks of topical corticosteroid therapy. We assessed parameter reproducibility (in healthy volunteers), baseline EDmin and EDmax, postcorticosteroid changes in EoE patients, and correlation with clinical response. Results: EDmin and EDmax were reproducible, with nonsignificant variance in the 2 esophagrams in control subjects (P = .44 and P = .66, respectively). Baseline EDmax was reduced in EoE at 19 mm (range, 13–26 mm) vs 24 mm (range, 19–29 mm) in controls (P = .004). About 50% of the EoE patients had EDmax and min values within the 10th to 90th percentile of controls (45% and 55%, respectively). Clinical improvement by Mayo Dsyphagia Questionnaire did not correlate with postcorticosteroid luminal change (P = .19 for EDmax; P = .75 for EDmin). Median increases in postcorticosteroid EDmax and EDmin were not statistically significant (P = .15 and .1, respectively). However, they were significant in patients with abnormal baseline EDmax (n = 6; 2 mm; P = .01) and EDmin (n = 5; 3 mm; P = .02). Conclusions: Esophageal diameter is a reproducible parameter that is frequently decreased in EoE, but normal in approximately 50% of patients. Those with narrowing might respond to steroids, but it is unclear if narrowing causes dysphagia. 2013-04-16T04:57:31.465Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12768 Objective: To assess the incidence and mortality impact of upper and lower gastrointestinal (GI) events in rheumatoid arthritis (RA) compared to non-RA subjects. Methods: We identified incident upper and lower GI events and estimated their incidence rates using person-year methods in a population-based incident RA cohort of residents of Olmsted County, Minnesota, USA (1987 American College of Rheumatology criteria first fulfilled between January 1, 1980, and January 1, 2008) and non-RA subjects from the same population. Results: The study included 813 patients with RA and 813 non-RA subjects (mean followup 10.3 and 10.8 yrs, respectively); 68% women; mean age 55.9 yrs in both cohorts. The rate of upper GI events/100 person-years was 2.9 in RA versus 1.7 in the non-RA cohort (rate ratio 1.7, 95% CI 1.4, 2.2); for lower GI events, the rates were 2.1 in RA versus 1.4 in the non-RA cohort (rate ratio 1.5, 95% CI 1.1, 1.9). The incidence of upper GI bleed, perforation, ulcer, obstruction, and any upper GI event in RA declined over calendar time; the incidence of lower GI events remained unchanged. Exposure to glucocorticoids, prior upper GI disease, abdominal surgery, and smoking were associated with lower GI events in RA. Both upper and lower GI events were associated with increased mortality risk in RA. Conclusion: There is increased risk of serious upper and lower GI events in RA compared to non-RA subjects, and increased GI-related mortality in RA. Prominent declines in incidence of upper, but not lower GI events in RA highlight the need for studies investigating lower GI disease in patients with RA. 2013-04-16T04:56:24.299Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12767 Background: Smaller studies have evaluated SLC6A4 5-HTTLPR and GNβ3 825C>T polymorphisms in IBS, and interactions between 5-HTT LPR with life events have been reported in the psychiatric literature, but gene–environment studies in IBS are lacking. Aims: The purpose of this study was to assess the association of two polymorphisms with IBS and age of onset, and whether there are gene–environment interactions with IBS. Methods: Outpatients with IBS and controls completed a validated questionnaire and provided blood for DNA. Comparisons of genotype/allele frequencies between cases and controls were performed with logistic regression. Linear regression was used to evaluate the association between the variants and age of onset. Environmental variables tested included abuse, parental alcohol abuse, parental psychiatric disorders, and gastrointestinal infections. Results: Genotyping was performed in 385 cases and 262 controls with median age of 50 years (range, 18.0–70.0) and 498 (77 %) females. The IBS subtype distribution among cases was: 102 (26 %) D-IBS, 40 (10 %) C-IBS, 125 (32 %) M-IBS, 118 (31 %) other. No association was observed between IBS or age of onset and both variants. Significant interactions were observed between GI infection and the GNβ3 825T allele. For those reporting gastrointestinal infection, the OR for IBS was 3.9 (95 % CI 1.2–12.7) whereas the OR was 0.86 (95 % CI 0.65–1.13) for those without prior infection. Conclusions: There was a significant interaction between the GNβ3 polymorphism and infection in the development of IBS, suggesting that its etiology is the result of a combination of specific genetic and environmental risk factors. 2013-04-16T04:55:28.147Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12766 Case series have suggested an association between eosinophilic esophagitis (EoE) and celiac disease (CD) in children. We analyzed a cohort of patients with CD to confirm this association in children, and determine whether it extends into adulthood. A database of patients with CD was reviewed to determine the number of patients with comorbid diagnoses of EoE. Histopathology reports of esophageal biopsies were reviewed to identify all cases of increased esophageal eosinophilia. Cases of EoE were diagnosed if biopsies revealed >=15 eosinophils per high power field and associated symptoms were present. Age-adjusted and sex-adjusted standardized incidence ratios (SIR) with corresponding 95% confidence intervals (CI) were calculated in comparison to published US population-derived incidence data. EoE was diagnosed in 4 children and 10 adults. EoE is more common compared with the general population; SIR for children was 35.6 (95% CI, 9.3-79.0) and for adults 13.1 (95% CI, 6.2-22.5). Overall, the age-adjusted and sex-adjusted SIR was 16.0 (95% CI, 8.7-25.5). The incidence of EoE in our cohort of patients with CD was increased compared with the general population. Coexistent EoE should be considered in patients with CD who have persistent esophageal symptoms. 2013-04-16T04:54:28.043Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12765 Gastroparesis (GP) is characterized by delayed gastric emptying in the absence of mechanical outlet obstruction. Symptoms may include nausea, vomiting, bloating, early satiety, abdominal pain, and weight loss. Delayed gastric emptying of a solid-phase meal assessed by radionuclear scintigraphy is the criterion standard for diagnosis. The prevalence of GP is difficult to estimate due to the lack of a validated, widely available diagnostic test that can be applied in primary care. The extent of this problem in children is unknown. We studied a cohort of children with GP diagnosed by radionuclear scintigraphy to identify demographics, symptoms, comorbidities, treatment, and outcomes. A retrospective analysis of 239 patients between ages 0 and 21 years was performed. The mean age of presentation was 7.9 years, and boys and girls were almost equally affected, that is, 48.5% and 51.5%, respectively. Vomiting was the most frequent presenting symptom (68%), followed by abdominal pain (51%), nausea (28%), weight loss (27%), early satiety (25%), and bloating (7%). Almost 75% of patients responded to intravenous erythromycin administered provocatively during gastric scintigraphy. In a majority of the patients, no cause was identified, that is, idiopathic GP (70%), followed by drugs (18%) and postsurgical (12.5%) causes. Only 4% patients had diabetic GP, and our population was essentially narcotic naive (2%). After an average of 24 months' follow-up, the most common complication was esophageal reflux (67%). Despite different therapeutic modalities, by the end of the follow-up period, a significant improvement in symptoms was reported by an average of 60%, regardless of sex, age, or degree of emptying delay. GP has a good prognosis in childhood despite different etiologies, symptom presentation, and therapy. 2013-04-16T04:53:27.762Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12764 Functional dyspepsia (FD) is a common problem affecting up to 10–25% of individuals. FD accounts for significant health care costs and affects quality of life but has no definitive treatment. The Functional Dyspepsia Treatment Trial (FDTT) aims to test whether treatment with an antidepressant (amitriptyline or escitalopram) leads to improvement of symptoms in patients with moderate to severe FD. The FDTT is an international multicenter, parallel group, randomized, double-blind, placebo-controlled trial to evaluate whether 12 weeks of treatment with escitalopram or amitriptyline improves FD symptoms compared to treatment with placebo. Secondly, it is hypothesized that acceleration of solid gastric emptying, reduction of postprandial satiation, and enhanced gastric volume change with a meal will be significant positive predictors of short- and long-term outcomes for those on antidepressants vs. placebo. The third aim is to examine whether polymorphisms of GNβ3 and serotonin reuptake transporter influence treatment outcomes in FD patients receiving a tricyclic antidepressant, selective serotonin reuptake inhibitor therapy, or placebo. The FDTT enrollment began in 2006 and is scheduled to randomize 400 patients by the end of 2012 to receive an antidepressant or placebo for 12 weeks, with a 6-month post-treatment follow-up. The study incorporates multiple validated questionnaires, physiological testing, and specific genetic evaluations. The protocol was approved by participating centers' Institutional Review Boards and an independent Data Safety Monitoring Board was established for monitoring to ensure patient safety and a single interim review of the data in December 2010 (ClinicalTrials.gov number NCT00248651). 2013-04-16T04:52:31.853Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:11817 Research Doctorate - Doctor of Philosophy (PhD) 2013-04-09T04:56:21.609Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12751 Research Doctorate - Doctor of Philosophy (PhD) 2013-04-09T04:47:48.661Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12749 Within Australian tertiary institutions, student engagement has received much attention in recent times, despite the obscurity in its meaning. The term ‘engagement’ has become synonymous with student ‘involvement’ and ‘active participation’, suggesting that international students are accountable for their lack of engagement. However, this fails to acknowledge the pivotal role of lecturers and course structure. Students are encouraged to communicate and collaborate with peers as a way of negotiating and constructing knowledge, though lecturers do little to foster a participative learning environment. This article considers the difficulties international students face in achieving success at a satellite campus in Sydney following the research conducted on student engagement. The article suggests that in order to increase the level of international student engagement, communication, assessments and the lecturer’s pedagogy need to be addressed. 2013-04-08T07:31:18.549Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12748 There is a consensus in the literature that mathematical ability contributes to student success in tertiary education. More importantly, mathematical skills are necessary when successfully completing mathematics- and/or science-based degrees. Social sciences such as psychology and economics require statistical skills which also require knowledge of mathematics. Even business students, such as marketing and accounting students need the necessary mathematical skills to successfully complete their degrees at university. This paper suggests that student success in a core business subject is dependent on their mathematical aptitude, attitude, and type of secondary schooling whether government or non-government schools. There is urgency for universities to recognize that high failure rates are due to insufficient mathematics exposure in secondary schooling and remedial classes might not be enough. Specifying a minimum (maths, e.g., two units) requirement for entry and/or providing bridging programs to ensure students have the necessary basic mathematical skills would increase student success in quantitative units. 2013-04-08T07:30:22.560Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12740 Research Doctorate - Doctor of Philosophy (PhD) 2013-04-07T23:50:47.660Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12728 One of the major objectives in multimedia research is to provide pervasive access and personalized use of multimedia information. Pervasive access of video data implies the access of cognitive and affective aspects of video content. Personalized use requires the services satisfy individual user’s needs on video content. This article attempts to provide a content-on-demand (CoD) video adaptation solution by considering users’ preference on cognitive content and affective content for video media in general, sports video and movies in particular. In this article, CoD video adaptation system is developed to support users’ decision in selecting their content of interest and adaptively deliver video source by selecting relevant content and dropping frames while considering network conditions. First, video contents are annotated by the description schemes (DSs) provided by MPEG-7 multimedia description schemes (MDSs). Then, to achieve a generic adaptation solution, the adaptation is developed following MPEG-21 Digital Item Adaptation (DIA) framework. We study the MPEG-21 reference software on XML generation and develop our own system for CoD video adaptation in three steps: (1) the content information is parsed from MPEG-7 annotation XML file together with bitstream to generate generic Bitstream Syntax Description (gBSD); (2) Users’ preference, network characteristic and adaptation QoS (AQoS) are considered for making adaptation decision; (3) adaptation engine automatically parses adaptation decisions and gBSD to achieve adaptation. Unlike most existing adaptation work, the system adapts the content of interest in the video stream according to users’ preference. We implement the above-mentioned MPEG-7 and MPEG-21 standards and provide a generic video adaptation solution. Adaptation based on gBSD avoids complex video computation. Thirty students from various departments were invited to assess the system and their responses have been positive. 2013-04-04T05:23:01.158Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:11803 Driver assistant systems enhance traffic safety and efficiency. The accurate 3D pose of a front vehicle can help a driver to make the right decision on the road. We propose a novel real‐time system to estimate the 3D pose of the front vehicle. This system consists of two parallel threads: vehicle rear tracking and mapping. The vehicle rear is first identified in the video captured by an onboard camera, after license plate localization and foreground extraction. The 3D pose estimation technique is then employed with respect to the extracted vehicle rear. Most current 3D pose estimation techniques need prior models or a stereo initialization with user cooperation. It is extremely difficult to obtain prior models due to the varying appearance of vehicles’ rears. Moreover, it is unsafe to ask for drivers’ cooperation when a vehicle is running. In our system, two initial keyframes for stereo algorithms are automatically extracted by vehicle rear detection and tracking. Map points are defined as a collection of point features extracted from the vehicle’s rear with their 3D information. These map points are inferences that relate the 2D features detected in following vehicles’ rears with the 3D world. The relative 3D pose of the onboard camera to the front vehicle rear is then estimated through matching the map points with point features detected on the front vehicle rear. We demonstrate the capabilities of our system by testing on real‐time and synthesized videos. In order to make the experimental analysis visible, we demonstrated an estimated 3D pose through augmented reality, which needs accurate and real‐time 3D pose estimation. 2013-04-04T05:21:50.098Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:11542 Background: Central nervous system–depressant (CNS-Ds) drugs can impair cognitive functions and driving. They are also the most common drugs taken in overdose in hospital-treated episodes of self-poisoning. In Australia most of these patients are discharged within 48 h, while they still have possible subclinical drug effects. We aimed to determine whether patients treated for self-poisoning with CNS-Ds are impaired in the Trail-Making Test (TMT, parts A and B), a neuropsychological test that is known to correlate with driving performance. Methods: This study was a conducted from November 2008 to April 2011 in a referral center for poisonings in New South Wales, Australia. One hundred seven patients discharged from the clinical toxicology unit following treatment for self-poisoning of CNS-Ds (benzodiazepines, atypical antipsychotics, or opioids) and a control group of 68 discharged following self-poisoning of non-CNS-depressant drugs (acetaminophen or nonsedating antidepressants) were tested with the TMT (parts A and B). Due to the known association of impaired TMT with driving impairment and increased risk of traffic accidents, performance less than the 10th percentile for age was defined as significant impairment in each part of the TMT. The odds ratio (OR) for impairment in each part was calculated in multivariate logistic regression (MLR) models adjusted for gender, education, IQ, and the presence of a major psychiatric illness. A secondary MLR analysis was conducted only for those patients (78 CNS-D and 54 control group participants) who were directly discharged home, after excluding those who were transferred for further psychiatric care. Results: The odds of impairment in the CNS-D group was 2.8 times that of the control group on the TMT-A (38 [35.5%] vs. 11 [16.2%]: adjusted OR = 2.76, 95% confidence interval [CI]: 1.28–5.97), and 4.6 times on the TMT-B (67 [62.6%] vs. 22 [32.4%]: adjusted OR = 4.63, 95% CI: 2.06–10.42). The results were similar in the subgroup of patients discharged home, and the odds of impairment in the CNS-D group was 3.3 times that of the control group on the TMT-A (25 [32.1%] vs. 7 [13.0%]: adjusted OR = 3.30, 95% CI: 1.28–8.52), and 3.6 times on the TMT-B (46 [59.0%] vs. 17 [31.5%]: adjusted OR = 3.64, 95% CI: 1.44–9.20). TMT-B impairment in the CNS-D group remained significant even after adjusting for TMT-A performance. Conclusions: Patients with CNS-D overdose may have significant impairment in cognitive skills underlying driving at the time of discharge from hospitals. Clinicians should warn these patients that their driving skills might still be impaired, even if they are considered clinically recovered and advise them not to drive during the first 1 to 2 days following discharge. 2013-04-03T03:57:23.964Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:11541 CNS-depressant drugs (CNS-Ds) are known to impair cognitive functions. Overdose of these drugs is common and the majority of the hospital-treated patients are discharged within 24–48 hours. No previous studies have examined whether they have residual impairment at the time of discharge. Our aim was to evaluate whether patients with CNS-D overdose are impaired in cognitive domains important in daily activities at that time. We compared visuomotor skills (Trail-Making A and choice reaction time), executive functions (viz. attentional set-shifting: Trail-Making B, and planning: Stockings of Cambridge task [SOC] from the Cambridge Neuropsychological Test Automated Battery [CANTAB]), working memory (Letter-Number Sequencing) and impulsivity and decision-making (CANTAB Information Sampling) in 107 patients with CNS-D overdose (benzodiazepines, opioids or antipsychotics) with a Control Group of 68 with non-CNS-D overdose (acetaminophen, SSRI and SNRIs) on discharge from hospital. Outcome measures were adjusted for demographic and clinical covariates in multivariate regression models. Compared to the Controls, the CNS-D Group was significantly impaired in all domains: they had prolonged Trail-Making completion times and reaction times, poorer working memory and planning and were more impulsive in decision-making. Their SOC performance was comparable to the Control Group for simple problems but worsened with increasing task complexity. The results show that patients with CNS-D overdose could be impaired in multiple cognitive domains underlying everyday functioning even at the time they are deemed medically fit to be discharged. Such impairments could adversely affect social and professional lives of this relatively young population during the immediate post-discharge period. 2013-04-03T03:56:34.887Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:11889 Fertilization represents the culmination of a series of complex interactions between male and female gametes. Despite advances in our understanding, the precise molecular mechanisms underlying these fundamental interactions remain largely uncharacterized. There is however growing recognition that this process requires the concerted action of multiple sperm receptors that possess affinity for complementary zona pellucida ligands and those that reside on the surface of the oolemma. Among the candidate sperm proteins that have been implicated in fertilization, those belonging to the ADAM (a disintegrin and metalloprotease) family of proteases have received considerable attention. The focus of the studies described herein has been the characterization of a closely related member of this protease family, ADAMTS10 (a disintegrin and metalloprotease with thrombospondin type 1 motifs number 10). We have demonstrated that ADAMTS10 is expressed during the later stages of mouse spermatogenesis and incorporated into the acrosomal domain of developing spermatids. During sperm maturation, the protein appears to be processed before being expressed on the surface of the peri-acrosomal region of the head. Our collective data suggest that, from this position, ADAMTS10 participates in sperm adhesion to the zona pellucida. Indeed, pre-incubation of capacitated spermatozoa with either galardin, a broad spectrum inhibitor of metalloprotease activity, or anti-ADAMTS10 antisera elicited a significant reduction in their ability to engage in zona adhesion. Overall, these studies support the notion that sperm–oocyte interactions involve considerable functional redundancy and identify ADAMTS10 as a novel candidate in the mediation of these fundamentally important events. 2013-04-03T01:39:10.973Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:11756 The term Building Information Modelling (BIM) refers to an expansive knowledge domain within the design, construction and operation (DCO) industry. The voluminous possibilities attributed to BIM represent an array of challenges that can be met through a systematic research and delivery framework spawning a set of performance assessment and improvement metrics. This article identifies five complementary components specifically developed to enable such assessment: (i) BIM capability stages representing transformational milestones along the implementation continuum; (ii) BIM maturity levels representing the quality, predictability and variability within BIM stages; (iii) BIM competencies representing incremental progressions towards and improvements within BIM stages; (iv) Organizational Scales representing the diversity of markets, disciplines and company sizes; and (v) Granularity Levels enabling highly targeted yet flexible performance analyses ranging from informal self-assessment to high-detail, formal organizational audits. This article explores these complementary components and positions them as a systematic method to understand BIM performance and to enable its assessment and improvement. A flowchart of the contents of this article is provided. 2013-04-03T01:29:09.595Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12721 Tracking of triangular or sawtooth waveforms is a major difficulty for achieving high-speed operation in many scanning applications such as scanning probe microscopy. Such non-smooth waveforms contain high order harmonics of the scan frequency that can excite mechanical resonant modes of the positioning system, limiting the scan range and bandwidth. Hence, fast raster scanning often leads to image distortion. This paper proposes analysis and design methodologies for a nonlinear and smooth closed curve, known as Lissajous pattern, which allows much faster operations compared to the ordinary scan patterns. A simple closed-form measure is formulated for the image resolution of the Lissajous pattern. This enables us to systematically determine the scan parameters. Using internal model controllers (IMC), this non-raster scan method is implemented on a commercial atomic force microscope driven by a low resonance frequency positioning stage. To reduce the tracking errors due to actuator nonlinearities, higher order harmonic oscillators are included in the IMC controllers. This results in significant improvement compared to the traditional IMC method. It is shown that the proposed IMC controller achieves much better tracking performances compared to integral controllers when the noise rejection performances is a concern. 2013-03-28T02:49:20.662Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12698 Background: Sternal precautions are utilized within many hospitals with the aim of preventing the occurrence of sternal complications (eg, infection, wound breakdown) following midline sternotomy. The evidence base for sternal precaution protocols, however, has been questioned due to a paucity of research, unknown effect on patient outcomes, and possible discrepancies in pattern of use among institutions. Objective: The objective of this study was to investigate and document the use of sternal precautions by physical therapists in the treatment of patients following median sternotomy in hospitals throughout Australia, from immediately postsurgery to discharge from the hospital. Design: A cross-sectional, observational design was used. An anonymous, Web-based survey was custom designed for use in the study. Methods: The questionnaire was content validated, and the online functionality was assessed. The senior cardiothoracic physical therapist from each hospital identified as currently performing cardiothoracic surgery (N=51) was invited to participate. Results: The response rate was 58.8% (n=30). Both public (n=18) and private (n=12) hospitals in all states of Australia were represented. Management protocols reported by participants included wound support (n=22), restrictions on lifting and transfers (n=23), and restrictions on mobility aid use (n=15). Factors influencing clinical practice most commonly included “workplace practices/protocols” (n=27) and “clinical experience” (n=22). Limitations: The study may be limited by response bias. Conclusions: Significant variation exists in the sternal precautions and protocols used in the treatment of patients following median sternotomy in Australian hospitals. Further research is needed to investigate whether the restrictions and precautions used are necessary and whether protocols have an impact on patient outcomes, including rates of recovery and length of stay. 2013-03-25T06:35:35.732Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12696 Objective: To investigate the existing experience, training, confidence and knowledge of rural/remote health care practitioners in providing management for people with chronic obstructive pulmonary disease (COPD). Design: Descriptive cross-sectional, observational survey design using a written anonymous questionnaire. This study formed part of a larger project evaluating the impact of breathe easy walk easy (BEWE), an interactive education and training program for rural and remote health care practitioners. Setting: Rural (n = 1, New South Wales) and remote (n = 1, Northern Territory) Australian health care services. Participants: Health care practitioners who registered to attend the BEWE training program (n = 31). Main outcome measures: Participant attitudes, objective knowledge and self-rated experience, training and confidence related to providing components of management for people with COPD. Results: Participants were from a variety of professional backgrounds (medical, nursing, allied health) but were predominantly nurses (n = 13) or physiotherapists (n = 9). Most participants reported that they had minimal or no experience or training in providing components of management for people with COPD. Confidence was also commonly rated by participants as low. Mean knowledge score (number of correct answers out of 19) was 8.5 (SD = 4.5). Questions relating to disease pathophysiology and diagnosis had higher correct response rates than those relating more specifically to pulmonary rehabilitation. Conclusion: The results of this study indicate that some rural and remote health care practitioners have low levels of experience, knowledge and confidence related to providing components of management for people with COPD and that education and training with an emphasis on pulmonary rehabilitation would be beneficial. 2013-03-25T05:59:14.052Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12684 A two-stage study was undertaken to establish what effect, if any, perchloroethylene has on coal coking properties. Stage 1 was a kinetic study in which the Gieseler fluidity of samples of a high fluidity coal was measured over a 64-week period. Two of the samples were left untreated, with one stored in air and one immersed in water. The third sample was also stored in air, but was soaked in perchloroethylene for 2 h and then air dried immediately prior to fluidity testing. In Stage 2, seven different coking coals were studied, covering three different Australian coal measures and a wide range of coking rank. For each coal, a 40 kg clean coal composite was formed using laboratory water-based methods, a Reflux Classier for the 0.038–0.25 mm and 0.25–2.0 mm size fractions and a Mintek jig for the 2.0–16 and 16–50 mm size fractions. This 40 kg composite was then subdivided into four sub-samples. Samples A and B were coked immediately, whereas Samples C and D were stored in open trays at ambient conditions for a month before coking. Samples B and D were soaked in perchloroethylene for 2 h and then air dried prior to coke testing, whereas Samples A and C were left untreated. Coal properties were measured prior to coking, and after coking the NSC Coke Reactivity Index (CRI) and Coke Strength after Reaction (CSR) were measured. In Stage 1 it was found that storage under water was able to maintain the sample fluidity better than refrigerated storage. The combined Stage 1 and 2 results showed that perchloroethylene had a detrimental effect on the coking properties of many coals. Hence coking tests on clean coal composites formed using heavy organic liquids may often under predict a coal’s true coking properties. This could lead to many coal deposits being undervalued. Perchloroethylene had the largest detrimental effect on the fluidity, CRI and CSR of coals that started with relatively poor properties. Perchloroethylene had a negligible effect on coals with relatively good initial coking properties. There was no clear correlation with vitrinite reflectance. The three most seriously affected coals all had relatively high inertinite content. It is speculated that the higher porosity of inertinite might allow greater access and retention of perchloroethylene in the coal particles. The laboratory water-based methods were able to produce clean coal composites that matched the proximate, petrographic and coal swelling number properties of the coal preparation plant product. The dilatometer and fluidity results were lower than those of the coal preparation plant, but this can be explained by the up to three month delay between mining of the original sample and the coking of the composite. These delays were an unavoidable part of the research nature of this project and had nothing to do with the water based methods deployed. If these water-based methods of preparing clean-coal composites were to become standardized, then there is no reason why a well equipped coal testing facility could not receive a refrigerated bore core and produce a clean coal composite within the period of a week. 2013-03-24T22:50:19.901Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12647 With over 100 millions tons of coal exported annually, the coal terminals at the Port of Newcastle are among the busiest in the world. To accommodate the anticipated rise in the export of coal in the next decade, effective stockyard management at the coal terminals will be essential. We have developed stockyard planning technology that can achieve substantially higher throughput levels. The technology intelligently combines greedy construction, enumeration, and integer programming. We demonstrate the efficacy of the technology on a variety of instances derived from real-life data and also show how the technology can be used to investigate the benefits of capacity expansion investments on throughput levels. 2013-03-18T04:04:41.760Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:11734 We investigate the use of compressive sampling for networked feedback control systems. The method proposed serves to compress the control vectors which are transmitted through rate-limited channels without much deterioration of control performance. The control vectors are obtained by an ℓ¹-ℓ² optimization, which can be solved very efficiently by FISTA (Fast Iterative Shrinkage-Thresholding Algorithm). Simulation results show that the proposed sparsity-promoting control scheme gives a better control performance than a conventional energy-limiting L²-optimal control. 2013-03-17T23:54:47.773Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:11733 Herein we present an algorithm for controlling LTI processes using an adaptive sampling interval where the controller at every sampling instant not only computes the new control command but also decides the time interval to the next sample. The approach relies on MPC where the cost function depends on the control performance as well as the cost for sampling. The paper presents a method for synthesizing such a predictive controller and gives explicit conditions for when it is stabilizing. Further it is shown that the optimization problem may be solved off-line and that the controller may be implemented as a lookup table of state feedback gains. The paper is concluded with a numerical example. 2013-03-17T23:54:15.584Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12635 Masters Research - Master of Philosophy (MPhil) 2013-03-13T00:52:23.257Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12634 Research Doctorate - Doctor of Philosophy (PhD) 2013-03-13T00:05:56.619Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12632 Research Doctorate - Doctor of Philosophy (PhD) 2013-03-12T22:25:00.329Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:11650 We study a predictive control formulation for uncertain discrete-time non-linear uniformly continuous plant models where controller output data is transmitted over an unreliable communication channel. The channel introduces Markovian data-loss and does not provide acknowledgments of receipt. To achieve robustness with respect to dropouts, at every sampling instant the controller transmits packets of data. These contain possible control inputs for a finite number of future time instants, and minimize a finite horizon cost function. At the actuator side, received packets are buffered, providing the plant inputs. Within this context, we adopt a stochastic Lyapunov function approach to establish stability results of the networked control system. A distinguishing aspect of this work is that it considers situations where the maximum number of consecutive packet dropouts has unbounded support. 2013-03-07T23:39:58.884Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:11732 We study stochastic stability of centralized Kalmanfiltering for linear time-varying systems equipped with wireless sensors. Transmission is over fading channels where variable channel gains are counteracted by power control to alleviate the effects of packet drops. We establish sufficient conditions for the expected value of the Kalman filter covariance matrix to be exponentially bounded in norm. The conditions obtained are then used to formulate stabilizing power control policies which minimize the total sensor power budget. In deriving the optimal power control laws, both statistical channel information and full channel information are considered. The effect of system instability on the power budget is also investigated for both these cases. 2013-03-07T23:39:08.085Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:10678 In this paper, a finite control set model predictive controller for closed-loop control of an active front-end rectifier is presented. The proposed method operates in discrete time and does not require additional modulators. The key novelty of the control algorithm presented lies in the way dynamic references are handled. The control strategy is capable of providing suitable references for the source active power and the rectified voltage, without requiring additional control loops. Experimental results show that fast and accurate tracking of dynamic dc voltage and reactive power references can be achieved, while respecting the restrictions on maximum power levels of the rectifier. 2013-03-07T23:38:07.646Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:11591 Background: Use of psychotropic drugs is known to impair driving and increase the risk of road traffic accidents. They are also the most common drugs taken in overdose in hospital-treated episodes of self-poisoning. Most patients who take psychotropic drug overdoses are discharged within 48 hours, while they still have possible subclinical drug effects. Objective: Using a self-controlled case series design, we aimed to determine whether patients with psychotropic drug overdose are at a higher risk of a traffic accident in the period following discharge compared with a control period not associated with hospital-treated drug overdose. Methodology: Using the New South Wales (NSW) Admitted Patient Data Collection (APDC) as the primary source, we retrieved 40 845 hospital separation records dated between 1 July 2000 and 30 June 2008 (8 years) in patients aged 18-80 years admitted to a hospital in NSW following an intentional self-poisoning with a psychotropic drug (coded X61 or X62 as the International Classification of Diseases, 10th Edition, [ICD-10] external cause of injury). Of these, 33459 hospital separations (i.e. discharges, transfers and deaths) involving 24 284 patients were considered eligible as the patients were discharged directly into the community where they could have driven a motor vehicle. We selected three separate post-admission periods (3 days, 1 week and 4 weeks), subtracted the number of inpatient days from each and calculated three separate post-discharge periods (immediate, intermediate and extended, respectively) for each episode of overdose. The control period was the duration of the study period where the individual was aged 18 years or older, excluding the total person-days in the post-discharge period/s and the index inpatient period/s. The APDC dataset was linked to the NSW Roads and Traffic Authority CrashLink dataset to identify any accidents in which each patient was involved as a motor-vehicle driver during the follow-up period. Incidence rate ratio (IRR) for matched post-discharge and control periods was found using random effects Poisson regression. Results: Seventy-two percent of the subjects were discharged within 2 days following their admission with overdose. Compared with the corresponding control periods the risk of a traffic accident was 3.5 times higher (IRR = 3.49; 95% CI 1.66, 7.33; p = 0.001) during the immediate, 1.9 times higher (IRR = 1.88; 95% CI 1.09, 3.25; p = 0.023) during the intermediate and 1.6 times higher (IRR = 1.65; 95% CI 1.27, 2.15; p = 0.0002) during the extended post-discharge period. Conclusions: Self-poisoning with psychotropic drugs is associated with a markedly increased risk of a traffic accident during the first few days following discharge. These findings raise clinical and medico-legal implications concerning fitness-to-drive during this period. The risk reduces with time but remains significantly elevated after 4 weeks post-overdose. Further research is necessary to find out the factors contributing to this ongoing risk. 2013-03-07T04:24:54.634Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12537 To minimize procurement expenditures both purchasing and transportation costs need to be considered. We study a procurement setting in which a company needs to purchase a number of products from a set of suppliers to satisfy customer demand. The suppliers offer total quantity discounts and transportation costs are based on truckload shipping rates. The goal is to select a set of suppliers so as to satisfy product demand at minimal total costs. The resulting optimization problem is strongly NP-hard. We develop integer programming based heuristics to solve the problem. Extensive computational experiments demonstrate the efficacy of the proposed heuristics and provide insight into the impact of instance characteristics on effective procurement strategies. 2013-03-07T04:20:02.600Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12542 Numerous planning models within the chemical, petroleum, and process industries involve coordinating the movement of raw materials in distribution networks so they can be blended into final products. The uncapacitated fixed-charge transportation problem with blending (FCTPwB) studied in this paper captures a core structure encountered in many of these environments. We model the FCTPwB as a mixed-integer linear program, and we derive two classes of facets, both exponential in size, for the convex hull of solutions for the problem with a single consumer and show that they can be separated in polynomial time. Furthermore, we prove that, in certain situations, these classes of facets along with the continuous relaxation of the original constraints yield a description of the convex hull. Finally, we present a computational study that demonstrates that these classes of facets are effective in reducing the integrality gap and solution time for more general instances of the FCTPwB with arc capacities and multiple consumers. 2013-03-07T04:10:04.374Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12543 Consider a network N = (N, A) and associate with each arc e ∈ A a fixed cost c_e for using arc e, an interval [l_e, u_e] (l_e, u_e ∈ ℤ) specifying the range of allowable resource consumption quantities along arc e, and a per-unit cost c_e for resource consumed along e. Furthermore, for each node n ∈ N, let U_n ∈ ℤ be the maximum amount of resource consumption a path can accumulate before visiting node n. Given a source node n_s ∈ N and sink node n_t ∈ N, the fixed-charge shortest-path problem (FCSPP) seeks to find a minimum-cost-feasible path from n_s to n_t . When resource consumption is simply additive, the resource-constrained shortest-path problem (RCSPP) is a special case of FCSPP. We develop a new dynamic programming algorithm for FCSPP. The algorithm uses solutions from labeling and dominance techniques for standard RCSPPs on slightly modified problems, and it combines these solutions by exploiting the structure provided by certain classes of knapsack problems to efficiently construct an optimal solution to FCSPP. Computational experiments demonstrate that our algorithm is often several orders of magnitude faster than naive dynamic programming procedures. 2013-03-07T04:10:04.351Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12538 A branch-price-and-cut algorithm is developed for a complex maritime inventory-routing problem with varying storage capacities and production/consumption rates at facilities. The resulting mixed-integer pricing problem is solved exactly and efficiently using a dynamic program that exploits certain “extremal” characteristics of the pricing problem. The formulation is tightened by using the problem’s boundary conditions in preprocessing and to restrict the set of columns that are produced by the pricing problem. Branching schemes and cuts are introduced that can be implemented efficiently and that preserve the structure of the pricing problem. Some of the cuts are inspired by the capacity cuts known for the vehicle-routing problem, whereas others specifically target fractional solutions brought about by individual vessels “competing” for limited inventory at load ports and limited storage capacity at discharge ports. The branch-price-and-cut approach solves practically sized problems motivated by the operations of an oil company to optimality, and it provides reasonable bounds for larger instances. 2013-03-07T04:00:03.415Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12539 Adjusting prices to influence demand so as to increase revenue has become common practice. We investigate adjusting prices to influence demand so as to reduce cost. More specifically, we consider offering price discounts in return for production and delivery flexibility. We do so in the context of the single-item, single-level uncapacitated lot-sizing problem. We show that even though the resulting optimization problem has a nonlinear objective function it can still be solved in polynomial time. Furthermore, we report results of a computational study analyzing the benefits of offering price discounts in return for production and delivery flexibility in various settings. 2013-03-07T04:00:03.414Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12540 Dynamic ride-share systems aim to bring together travelers with similar itineraries and time schedules on short-notice. These systems may provide significant societal and environmental benefits by reducing the number of cars used for personal travel and improving the utilization of available seat capacity. Effective and efficient optimization technology that matches drivers and riders in real-time is one of the necessary components for a successful dynamic ride-share system. We systematically outline the optimization challenges that arise when developing technology to support ride-sharing and survey the related operations research models in the academic literature. We hope that this paper will encourage more research by the transportation science and logistics community in this exciting, emerging area of public transportation. 2013-03-07T03:10:03.178Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12613 Aims of the document: To provide a summary of research, monitoring and other findings from native forest rehabilitation research undertaken at Xstrata Coal mines in the Hunter to assist mine personnel with sustainable rehabilitation of spoil placement areas and restoration lands ; To recommend rehabilitation and restoration actions ; To propose how the above actions could be further developed through on-going monitoring and research. 2013-03-07T02:10:23.912Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:10945 Based on self-categorization theory, group status should be positively related to group prototypicality when the relevant superordinate category is positively valued. In this case, high-status groups should be perceived to be more prototypical than low-status groups even in the absence of concerns about maintaining a positive social identity. To test this hypothesis, a minimal group study was conducted in which participants (N = 139) did not belong to any of the groups involved. Consistent with predictions, participants perceived high-status groups to be significantly more prototypical than low-status groups. Consistent with self-categorization theory's cognitive analysis, these results demonstrate that the relation between group status and group prototypicality is a relatively basic and pervasive effect that does not depend on social identity motives. 2013-03-06T05:11:31.114Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:11903 We prove a q-series identity that generalizes Macdonald's A⁽²⁾_2n η-function identity and the Rogers–Ramanujan identities. We conjecture our result to generalize even further to also include the Andrews–Gordon identities. 2013-03-06T04:45:06.967Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:11830 This article explores the conflict between the constructions of childhood and their political/legal implications in the context of the entertainment business, as related to the demands imposed upon children by parents and theatre managers in the late nineteenth and early twentieth centuries. Once children could move freely both within and between countries, these conflicts and concerns assumed a global dimension. Through a number of case studies, the authors offer some fresh observations about how legal and social imperatives affected the transmission of values about children employed as entertainers between Britain and Australasia during the period from 1870 to the start of the First World War – from the Education Acts of the 1870s to the legislation of 1910–1913 restricting the export of child entertainers. 2013-03-06T04:36:25.736Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:11895 We prove the conjectural relations between Mahler measures and L-values of elliptic curves of conductors 20 and 24. We also present new hypergeometric expressions for L-values of elliptic curves of conductors 27 and 36. Furthermore, we prove a new functional equation for the Mahler measure of the polynomial family (1+X)(1+Y)(X+Y)−αXY, α∈ℝ. 2013-03-06T04:35:01.440Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:11825 The reaction of Americans to the terrorist attacks of September 11, 2001, has been massively disproportionate to the actual threat posed by al-Qaida either as an international menace or as an inspiration or model for homegrown amateurs. An examination of the activities of international and domestic terrorist “adversaries” reveals that exaggerations and distortions of the threat have inspired a determined and expensive quest to ferret out, and even to create, the nearly nonexistent. The result has been an ill-conceived and remarkably unreflective effort to react to an event that, however tragic and dramatic in the first instance, should have been seen to be of only limited significance at least after a few years. Not only has the terrorism delusion had significant costs, but the initial alarmed perspective has been so internalized that anxieties about terrorism have persisted for more than a decade despite exceedingly limited evidence that much fear is justified. 2013-03-06T04:30:41.496Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12593 This lead article in this Special Issue begins discussion on an environmental ethics for social work and raises arguments as to whether and, if so, why social workers have duties, obligations, responsibilities and commitments to the non-human world. It provides an overview of the field of environmental ethics in searching for a moral stance to affirm an environmental social work. To what extent should social workers engage in fundamental geopolitical issues concerned with climate change, global warming, environmental degradation, pollution, chemical contamination, sustainable agriculture, disaster management, pet therapy, wilderness protection and so on and, if so, why and how? Are these issues incidental and peripheral and only of concern when they impact upon humans or do social workers have a responsibility beyond human interests? What is the significance of the ‘non-human’ for social work? The article explores the terrain of the burgeoning field of environmental ethics to determine whether convincing ethical grounds for environmental social work might be found beyond hortatory claims of what the profession ought to be doing to address environmental concerns. 2013-03-05T22:20:13.396Z ]]>