http://nova.newcastle.edu.au/vital/access/services/Feed ${session.getAttribute("locale")} 5 http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12946 We present a symmetric version of the nonsymmetric mixed finite element method presented in (Lamichhane, ANZIAM J 50 (2008), C324–C338) for nearly incompressible elasticity. The displacement–pressure formulation of linear elasticity is discretized using a Petrov–Galerkin discretization for the pressure equation in (Lamichhane, ANZIAM J 50 (2008), C324–C338) leading to a non-symmetric saddle point problem. A new three-field formulation is introduced to obtain a symmetric saddle point problem which allows us to use a biorthogonal system. Working with a biorthogonal system, we can statically condense out all auxiliary variables from the saddle point problem arriving at a symmetric and positive-definite system based only on the displacement. We also derive a residual based error estimator for the mixed formulation of the problem. 2013-05-23T04:51:48.547Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12945 Background: Transforaminal injection of steroids (TFIS) is effective for some patients with lumbar radicular pain caused by disc herniation. Factors associated with better outcomes are unknown. Objective: To identify clinical and radiological features predictive of a favorable response to TFIS. Methods: Seventy-one patients with lumbar radicular pain caused by disc herniation were treated with TFIS as part of a previously reported, randomized, clinical trial. The clinical features analyzed were the presence of neurologic symptom, neurologic signs, and the duration of sciatica. Radiological features evaluated using magnetic resonance imaging (MRI) were the segmental level of the pathology, the location and morphological features of the disc herniation, the cross-sectional area of the disc herniation and its ratio to the cross-sectional area of the spinal canal, and the grade of nerve root compression. Results: None of the clinical features was associated with successful outcome from treatment. The only radiological feature associated with successful outcome was the grade of nerve root compression. Of patients with low-grade root compression, 75% responded favorably to TFIS. Only 26% of patients with high-grade nerve root compression responded. Discussion: These results indicate that TFIS is more often successful in patients without significant compression of the nerve root and, therefore, in whom an inflammatory basis for radicular pain is most likely. In such patients, a success rate of 75% renders TFIS an attractive alternative to surgery. In patients with significant compression of the nerve root, the likelihood of benefiting from TFIS is low. The success rate may be no more than that of a placebo effect, and surgery may be a more appropriate consideration. 2013-05-22T06:35:00.741Z ]]> 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:12941 We study several generalizations of the AGM continued fraction of Ramanujan inspired by a series of recent articles in which the validity of the AGM relation and the domain of convergence of the continued fraction were determined for certain complex parameters (Borwein et al., Exp. Math. 13, 275–286, 2004, Ramanujan J., in press, 2004; Borwein and Crandall, Exp. Math. 12, 287–296, 2004). A study of the AGM continued fraction is equivalent to an analysis of the convergence of certain difference equations and the stability of dynamical systems. Using the matrix analytical tools developed in 2004, we determine the convergence properties of deterministic difference equations and so divergence of their corresponding continued fractions. 2013-05-22T04:40:56.735Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12938 We provide a proof of a conjecture in [Bailey et al. 07a] on the existence and form of linear recurrences for moments of powers of the Bessel function K₀. 2013-05-22T04:39:03.878Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12937 It is shown that various first and second order derivatives of the Fitzpatrick and Penot representative functions for a maximal monotone operator T, in a reflexive Banach space, can be used to represent differential information associated with the tangent and normal cones to the Graph T. In particular we obtain formula for the proto-derivative, as well as its polar, the normal cone to the graph of T. First order derivatives are shown to be useful in recognising points of single-valuedness of T. We show that a strong form of proto-differentiability to the graph of T, is often associated with single valuedness of T. 2013-05-22T04:38:17.987Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12936 In this article we explore a variety of pleasing connections between analysis, number theory, and operator theory, while revisiting a number of beautiful inequalities originating with Hilbert, Hardy and others. We first establish the Hilbert inequality and then apply it to various multiple zeta values. In consequence we obtain the norm of the classical Hilbert matrix, in the process illustrating the interplay of numerical and symbolic computation with classical mathematics. 2013-05-22T04:37:30.904Z ]]> 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:12930 Objective: This analysis sought to determine whether patient self-report measures were associated with disruption to radiation therapy sessions due to anxiety among cancer patients undergoing radiation therapy to the head and neck region. Method: A cohort of patients undergoing radiation therapy to the head and neck region at a major regional radiation oncology treatment centre (ROTC) in Australia completed self-report measures of anxiety, history of panic and fears relevant to use of an immobilising mask. The treating Radiation Therapist (RT) rated the level of session disruption due to patient anxiety during the Computerised Tomography/Simulation (CT/Sim) (baseline) session and first treatment session. Results: Complete data were obtained for 90 patients. RTs rated 11 and 24% of patients as having some level of session disruption session due to anxiety at baseline and Treatment 1, respectively. Five factors were significantly associated with session disruption at baseline in bivariate analyses: currently taking psycho-active medication (p=0.008); fear of enclosed spaces (p=0.006); fear of face being covered up (p0=006); fear of movement restriction (p=0.041) and ever had an anxiety attack (p=0.034). Sensitivity ranged from 0.57 to 0.75 and specificity ranged from 0.68 to 0.90. Only session disruption at baseline predicted disruption at Treatment 1 (p<0.01). Conclusions: This study offers some preliminary insights into the prevalence of patient anxiety severe enough to cause session disruption and patient self-report measures which might be used to flag patients for prophylactic treatment. Further development and replication in a larger sample is warranted before introduction of these measures into routine practice. 2013-05-22T04:31:11.467Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12940 Of key importance in convex analysis and optimization is the notion of duality, and in particular that of Fenchel duality. This work explores improvements to existing algorithms for the symbolic calculation of subdifferentials and Fenchel conjugates of convex functions defined on the real line. More importantly, these algorithms are extended to enable the symbolic calculation of Fenchel conjugates on a class of real-valued functions defined on Rⁿ. These algorithms are realized in the form of the Maple package SCAT. 2013-05-22T04:02:00.930Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12939 We intend to show that a variety of trigonometric sums have unexpected closed forms by relating them to cognate integrals. We hope this offers a good advertisement for the possibilities of experimental mathematics, as well as providing both some entertaining examples for the classroom and a caution against over-extrapolating from seemingly compelling initial patterns. 2013-05-22T04:01:47.415Z ]]> 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:12929 Human myometrium develops phasic contractions during labor. Phosphorylation of caldesmon (h-CaD) and extracellular signal-regulated kinase 1/2 (ERK 1/2) has been implicated in development of these contractions, however the phospho-regulation of these proteins is yet to be examined during periods of both contraction and relaxation. We hypothesized that protein phosphorylation events are implicated in the phasic nature of myometrial contractions, and aimed to examine h-CaD and ERK 1/2 phosphorylation in myometrium snap frozen at specific stages, including; (1) prior to onset of contractions, (2) at peak contraction and (3) during relaxation. We aimed to compare h-CaD and ERK 1/2 phosphorylation in vitro against results from in vivo studies that compared not-in-labor (NIL) and laboring (L) myometrium. Comparison of NIL (n = 8) and L (n = 8) myometrium revealed a 2-fold increase in h-CaD phosphorylation (ser-789; P = 0.012) during onset of labor in vivo, and was associated with significantly up-regulated ERK2 expression (P = 0.022), however no change in ERK2 phosphorylation was observed (P = 0.475). During in vitro studies (n = 5), transition from non-contracting tissue to tissue at peak contraction was associated with increased phosphorylation of both h-CaD and ERK 1/2. Furthermore, tissue preserved at relaxation phase exhibited diminished levels of h-CaD and ERK 1/2 phosphorylation compared to tissue preserved at peak contraction, thereby producing a phasic phosphorylation profile for h-CaD and ERK 1/2. h-CaD and ERK 1/2 are phosphorylated during myometrial contractions, however their phospho-regulation is dynamic, in that h-CaD and ERK 1/2 are phosphorylated and dephosphorylated in phase with contraction and relaxation respectively. Comparisons of NIL and L tissue are at risk of failing to detect these changes, as L samples are not necessarily preserved in the midst of an active contraction. 2013-05-21T23:24:20.350Z ]]> 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:12927 The Mahler measure of a polynomial in several variables has been a subject of much study over the past thirty years — very few closed forms are proven but more are conjectured. In the case of multiple Mahler measures more tractable but interesting families exist. Using values of log-sine integrals we provide systematic evaluations of various higher and multiple Mahler measures. The evaluations in terms of log-sine integrals become particularly useful in light of the fact that log-sine integrals may be automatically reexpressed as polylogarithmic values. We present this correspondence along with related generating functions for log-sine integrals. Our initial interest in considering Mahler measures stems from a study of uniform random walks in the plane as first introduced by Pearson. The main results on the moments of the distance traveled by an nn-step walk, as well as the corresponding probability density functions, are reviewed. It is the derivative values of the moments that are Mahler measures. This work would be impossible without very extensive symbolic and numeric computations. It also makes frequent use of the new NIST Handbook of Mathematical Functions and similar tools. Our intention is to show off the interplay between numeric and symbolic computing while exploring the three mathematical topics in the title 2013-05-21T05:38:42.052Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12926 We investigate the moments of 3-step and 4-step uniform random walk in the plane. In particular, we further analyse a formula conjectured in BNSW expressing 4-step moments in terms of 3-step moments. Diverse related results including hypergeometric and elliptic closed forms for W₄(± 1) are given and two new conjectures are recorded. 2013-05-21T04:48:04.849Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12925 The article offers information on a study which explores the random walks of real numbers. It focuses on the number pi, a mathematical constant which can be generated by simple algorithms and behaves randomly. It describes and exhibits uniform walks of numbers and quantifies the two features of random walks. It also describes the classes of normality and nonnormality results and provides various examples. 2013-05-21T04:42:08.295Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12924 In recent times, attention has been directed to the problem of solving the Poisson equation, either in engineering scenarios (computational) or in regard to crystal structure (theoretical). Herein we study a class of lattice sums that amount to Poisson solutions, namely the n-dimensional forms ⏀_n(r₁,...,r_n) = 1/π²[formula could not be replicated]. By virtue of striking connections with Jacobi ϑ-function values, we are able to develop new closed forms for certain values of the coordinates r_k, and extend such analysis to similar lattice sums. A primary result is that for rational x, y, the natural potential ⏀²(x, y) is 1/π log A where A is an algebraic number. Various extensions and explicit evaluations are given. Such work is made possible by number-theoretical analysis, symbolic computation and experimental mathematics, including extensive numerical computations using up to 20,000-digit arithmetic. 2013-05-21T04:35:17.054Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12922 Stimulated by earlier work by Moll and his coworkers (Amdeberhan et al., Proc. Am. Math. Soc., 139(2):535-545, 2010), we evaluate various basic log Gamma integrals in terms of partial derivatives of Tornheim-Witten zeta functions and their extensions arising from evaluations of Fourier series. In particular, we fully evaluate LG_n = ∫₀¹logⁿΓ(x)dx for 1≤n≤4 and make some comments regarding the general case. The subsidiary computational challenges are substantial, interesting and significant in their own right 2013-05-21T04:30:50.302Z ]]> 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:10338 Recent years have seen the flowering of "experimental" mathematics, namely the utilization of modern computer technology as an active tool in mathematical research. This development is not limited to a handful of researchers, nor to a handful of universities, nor is it limited to one particular field of mathematics. Instead, it involves hundreds of individuals, at many different institutions, who have turned to the remarkable new computational tools now available to assist in their research, whether it be in number theory, algebra, analysis, geometry or even topology. These tools are being used to work out specific examples, generate plots, perform various algebraic and calculus manipulations, test conjectures, and explore routes to formal proof. Using computer tools to test conjectures is by itself a major time saver for mathematicians, as it permits them to quickly rule out false notions. 2013-05-21T02:00:47.498Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:10022 We use methods from convex analysis, relying on an ingenious function of Simon Fitzpatrick, to prove maximality of the sum of two maximal monotone operators on reflexive Banach space under weak transversality conditions. 2013-05-21T01:48:29.602Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:6446 We record and substantially extend what is known about the closed forms for various Bessel function moments arising in quantum field theory, condensed matter theory and other parts of mathematical physics. In particular, we develop formulae for integrals of products of six or fewer Bessel functions. In consequence, we are able to discover and prove closed forms for cn,k := ∫∞₀ tkKⁿ₀(t) dt with integers n = 1, 2, 3, 4 and k ≽ 0, obtaining new results for the even moments c₃,₂k and c₄,₂k. We also derive new closed forms for the odd moments sn,₂k₊₁ := ∫∞₀ t²k⁺¹I₀(t)Kⁿ₀¹₀(t) dt with n = 3, 4 and for tn,₂k₊₁ := ∫∞ ₀ t²k⁺¹I²₀(t)Kⁿ⁻²₀(t)dt with n = 5, relating the latter to Green functions on hexagonal, diamond and cubic lattices. We conjecture the values of s₅,₂k₊₁, make substantial progress on the evaluation of c₅,₂k₊₁, s₆,₂k₊₁ and t₆,₂k₊₁ and report more limited progress regarding c₅,₂k, c₆,₂k₊₁ and c₆,₂k. In the process, we obtain eight conjectural evaluations, each of which has been checked to 1200 decimal places. One of these lies deep in four-dimensional quantum field theory and two are probably provable by delicate combinatorics. There remains a hard core of five conjectures whose proofs would be most instructive, to mathematicians and physicists alike. 2013-05-21T01:38:50.263Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:7550 The field of statistics has long been noted for techniques to detect patterns and regularities in numerical data. In this article, we explore connections between statistics and the emerging field of ‘experimental mathematics’. These include both applications of experimental mathematics in statistics as well as statistical methods applied to computational mathematics. 2013-05-21T01:27:03.416Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:11145 In this paper we revisit the question of when the continuous linear image of a fixed closed convex cone K is closed. Specifically, we improve the main result of [3] by showing that for all, except for at most a σ porous set, of the linear mappings T from ℐⁿ into ℐၐ, not only is T(K) closed, but there is also a neighbourhood around T whose members also preserve the closedness of K. 2013-05-21T01:22:38.837Z ]]> 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:12783 In man and rabbit, anesthetic doses of the μ-opioid receptor agonist fentanyl cause systemic vasoconstriction. In unsedated dogs, intravenous infusion of fentanyl at 0.55 μg·kg⁻¹·min⁻¹ causes initial mild coronary vasodilatation but later vasoconstriction. Possible differential effects on baroreflex coronary vasodilator gain (ratio of percent change in circumflex conductance (CC) to aortic pressure induced by thoracic aorta balloon inflation) were studied in unsedated dogs in heart block (paced ventricles: Doppler probe on circumflex artery) during intravenous fentanyl infusion rates of 0.14, 0.28, 0.55 and 1.10 μg·kg⁻¹·min⁻¹. Fifteen minutes of fentanyl caused a rise in resting CC at the two lowest infusion rates, but a dose-dependent fall in CC and rise in aortic pressure at higher infusion rates. Gain of the vasodilator baroreflex increased at the two lowest infusion rates, but fell below pre-infusion gain at the highest infusion rates, suggesting that a physiological rise in μ-opioid receptor activity in the central nervous system may enhance baroreflex augmentation of CC in response to sudden rises in cardiac afterload. The effect is offset by coronary vasoconstriction induced during anesthetic doses. 2013-05-20T06:15:08.401Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12907 Objective: To review the association between income inequality and health status, and consider an appropriate nursing response. Primary Argument: Nursing has a rich heritage of advocating for a healthy society established on a foundation of social justice. The future legitimacy and success of public health nursing depends on recognising and appropriately addressing the social, economic and political determinants of health in the populations served. There is an incontrovertible association between population health status, absolute income levels and income inequality. Thus, along with other social determinants of health, income differentials within populations must be a fundamental consideration when planning and delivering nursing services. Ensuring that federal and state health policy explicitly addresses this key issue remains an important challenge for the nursing profession, the public health system and the Australian community. Conclusions: Higher mortality and worse health status occur in societies with higher income inequality. The relationship between income inequality and health appears to be determined both by relative access to resources for health gain and relative social position. The association between greater income equality and improved health may be explained by improved social cohesion. As social factors are at the root of much of health inequality, this knowledge needs to invoke political action and advocacy from the nursing profession to promote the development of healthy public policy. Including indicators of income inequality when planning and monitoring nursing services will enable services to measure to what extent they are based on the principle of social justice. 2013-05-20T04:31:55.931Z ]]> 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:9447 Background: Young children are not participating in recommended levels of physical activity and exhibit high levels of sedentary behaviour. Childcare services provide access to large numbers of young children for prolonged periods, yet there is limited experimental evidence regarding the effectiveness of physical activity interventions implemented in this setting. The aim of this study is to assess the effectiveness and acceptability of a multi-component physical activity intervention, delivered by childcare service staff, in increasing the physical activity levels of children attending long day care services. Methods/Design: The study will employ a cluster randomised controlled trial design. Three hundred children aged between 3-5 years from twenty randomly selected long day care services in the Hunter Region of New South Wales, Australia will be invited to participate in the trial. Ten of the 20 long day care services will be randomly allocated to deliver the intervention with the remaining ten services allocated to a wait list control group. The physical activity intervention will consist of a number of strategies including: delivering structured fundamental movement skill activities, increasing physical activity opportunities, increasing staff role modelling, providing children with a physical activity promoting indoor and outdoor environment and limiting children's small screen recreation and sedentary behaviours. Intervention effectiveness will be measured via child physical activity levels during attendance at long day care. The study also seeks to determine the acceptability and extent of implementation of the intervention by services and their staff participating in the study. Discussion: The trial will address current gaps in the research evidence base and contribute to the design and delivery of future interventions promoting physical activity for young children in long day care settings. 2013-05-20T01:33:40.553Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12897 Objective: To describe the experience of engaging senior clinical nurses as surge staff in a pandemic public health response and determine the effect of an on‑line training package and exercise participation on these individuals’ perceptions and confidence of being deployed during an influenza pandemic. Design: After action reviews, end of exercise surveys, and pre‑ and post‑training risk perceptions questionnaire completion. Setting: The study was conducted within the operational aspects of a public health exercise response to an influenza pandemic. Subjects: Clinical nurse consultants, nurse educators and nurse managers sourced from areas defined as not clinically critical during the early containment phase of an influenza pandemic response. Interventions: Four hour on‑line training package and a four day influenza pandemic exercise. Main outcome measures: Expert observation and self‑perceived appropriateness of surge staff and measured changes in risk perception. Results: Observers’ comments and after action reviews indicated that by the end of the deployment, day surge staff were able to perform public health surveillance functions competently. The end of day survey showed that the on‑line training package served as a useful reference document but alone was an inadequate means of equipping staff for deployment. Exercise pre‑ and post‑perceptions surveys found that self‑perceived knowledge and confidence in performing duties increased following the exercise from 46% to 93% (p<0.01) and from 46% to 90% (p<0.01), respectively. Conclusion: Clinical nurse consultants, nurse educators and nurse managers working within a health authority are an appropriate surge workforce during public health emergencies if provided with appropriate training and support. 2013-05-20T00:12:54.070Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12896 There is limited evidence for effective obesity treatment programs that engage men. This study evaluated the efficacy of two gender-tailored weight loss interventions for men, which required no face-to-face contact. This was a three-arm, randomized controlled trial: (1) Resources (n=54), gender-tailored weight loss materials (DVD, handbooks, pedometer, tape measure); (2) Online (n=53), Resources materials plus study website and e-feedback; and (3) Wait-list control (n=52). The interventions lasted 3 months and were grounded in Social Cognitive Theory. At 6 months, significantly greater weight loss was observed for the Online (−4.7 kg; 95 % CI −6.1, −3.2) and Resources (−3.7 kg; 95 % CI −4.9, −2.5) groups compared to the control (−0.5 kg; 95 % CI −1.4, 0.4). Additionally, both intervention groups significantly improved body mass index, percent body fat, waist circumference, blood pressure, physical activity, quality of life, alcohol risk, and portion size, compared to controls. Men achieved significant weight loss after receiving novel, minimal-contact, gender-tailored programs, which were designed for widespread dissemination. 2013-05-17T02:46:20.984Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:7551 Review of: The Princeton Companion to Mathematics. Edited by Timothy owers, with June Barrow-Green and Imre Leader. Princeton University Press, Princeton, NJ, 2008. $99.00. xxii+ 1034 pp., hardcover. ISBN 978-0-691-11880-2. 2013-05-16T05:23:43.804Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:7552 Herein we develop connections between zeta functions and some recent "mysterious" constants of nonlinear physics. In an important analysis of coupled Winfree oscillators, Quinn, Rand, and Strogatz [Quinn et al. 07] developed a certain N-oscillator scenario whose bifurcation phase offset small ⍉ is implicitly defined, with a conjectured asymptotic behavior sin ⍉ ~ 1−ᴄ₁/N, with experimental estimate ᴄ₁ = 0.605443657 . . .. We are able to derive the exact theoretical value of this "QRS constant" ᴄ₁ as a real zero of a particular Hurwitz zeta function. This discovery enables, for example, the rapid resolution of c1 to extreme precision. Results and conjectures are provided in regard to higher-order terms of the sin ⍉ asymptotic, and to yet more physics constants emerging from the original QRS work. 2013-05-16T05:01:40.840Z ]]> 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:12891 Mr Forsyth is a 42-year-old clerk who has been quite well until recently. He has become somewhat anxious about a vague central chest discomfort that comes on after dinner while sitting watching television and he says that he also gets it between games of squash, which he plays once a week in the evening. He feels that he has cause for concern because his grandfather and uncle died of a stroke and his father and aunt died of a heart attack. The patient has a brother with high blood pressure. Mr Forsyth was examined by his general practitioner who conducted some tests. All seemed normal except for his fasting serum cholesterol level, which was marginally raised at 8.0 mmol/litre (normal: less than 7.2 mmo 1/litre). He was referred for an exercise test. 2013-05-16T04:41:29.146Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12890 The role of central (CNS) 5-hydroxytryptamine (5-HT) nerves in the thermal and arterial chemoreflex control of sympathetic innervation of ear skin vessels was studied in groups of unanesthetized normal, CNS 5-HT deplete (intracisternal 5,7-dihydroxytryptamine injection) and pontine rabbits. Ear artery flow (and conductance) was measured by a Doppler transducer. The high vasomotor tone in the ear skin of normal animals at rest was inhibited by the arterial chemoreflex and warm environment. It was absent, however, at rest in CNS 5-HT deplete animals. In pontine rabbits the resting high vasomotor tone was not inhibited by the arterial chemoreflex or a warm environment. These data suggest that bulbospinal 5-HT nerves have a major excitatory influence on tonic sympathetic activity to ear vessels, and that the central inhibition of this activity by arterial chemoreflex and environmental warmth involves suprabulbar influences and a transmitter other than 5-HT. 2013-05-16T04:41:22.347Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12673 The peripheral vascular response to severe exercise was studied in 11 healthy conscious dogs instrumented with Doppler ultrasonic flow probes on the mesenteric, renal, and iliac arteries, and miniature pressure gauges in the aorta. The response to severe exercise was restudied in six of these dogs after recovery from a second operation producing complete heart block by the injection of formalin into the atrioventricular (AV) node. Three of these dogs also exercised while their ventricles were paced at rates of 100/min and 200/min. The untethered normal dogs ran at speeds of 15-25 miles/hr behind a mobile recording unit for a distance averaging 1.5 miles, while continuous measurements of arterial blood pressure and blood flow were telemetered and recorded on magnetic tape. Severe exercise in normal dogs increased heart rate from 84 to 259/min, arterial pressure from 89 to 140 mm Hg, flow resistance in the mesenteric and renal beds by 59 and 52% respectively, and iliac blood flow 479% above control, while mesenteric and renal blood flows remained constant and iliac resistance decreased by 73%. 2013-05-16T03:41:52.419Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12763 The Kubicek thoracic cylinder model of impedance cardiography (IC) for measuring beat-by-beat stroke volume (SV) was evaluated in controlled studies using the electromagnetic flowmeter (FM) as the reference technique. Assuming the validity of the Kubicek equation for stroke volume calculation, IC stroke volume was found to be a linear function of EM values at any one haematocrit over a wide range of SV, but the slope of the relationship fell as haematocrit fell. Experiments using the same equation in dogs, in which blood resistivity in vivo (pt) was made the dependent variable, and the EM-derived value was usedfor stroke volume, showed that pt was almost constant over a wide range of haematocrits. These findings were supported by studies in man and rabbit where Fick and thermodilution-derived values were used for stroke volume. When these data were applied to normotensive and hypertensive human subjects with normal hearts and lungs in controlled studies at rest, during tilting, with drug therapy and on exercise, IC measured stroke volume and cardiac output with a variability at least as good as the 9–11% acceptable for clinical use. This conclusion applied to thoracic configurations of d sizes and shapes from adult man to the neonate. In chronic disease states, while assessments of relative changes are valuable, absolute data are questionable. Further research is required under these conditions, as it is also for other models of IC, which are based on different asswnptions. 2013-05-16T03:35:32.482Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12456 Objective: To evaluate the feasibility and efficacy of a workplace-based weight loss program (Workplace POWER-WP) for male shift workers. Method: A prospective, two-armed randomized controlled trial of 110 overweight/obese (BMI 25–40) (mean [SD] age = 44.4 [8.6] years; BMI = 30.5 [3.6]) male employees at Tomago Aluminium aged 18–65. In October (2009) men were randomized to either (i) WP program (n = 65) or (ii) a 14-week wait-list control group (n = 45). The 3-month program involved one information session, program booklets, group-based financial incentives and an online component. Men were assessed at baseline and at 14-week follow-up for weight (primary outcome), waist circumference, BMI, blood pressure, resting heart rate, self-reported physical activity and dietary variables, and physical activity and dietary cognitions. Results: Intention-to-treat analysis using linear mixed models revealed significant between group differences for weight loss after 14 weeks (P < .001, Cohen's d = 0.34). Significant intervention effects were also found for waist circumference (P < .001, d = 0.63), BMI (P < .001, d = 0.41), systolic blood pressure (P = .02, d = 0.48), resting heart rate (P < .001, d = 0.81), physical activity (P = .03, d = 0.77), sweetened beverages (P < .02, d = 0.5–0.6) and physical activity-related cognitions (P < .02, d = 0.6). Conclusion: The WP program was feasible and efficacious and resulted in significant weight loss and improved health-related outcomes and behaviours in overweight male shift workers. 2013-05-14T23:29:46.461Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12455 Objective: To evaluate the feasibility and efficacy of the ‘Healthy Dads, Healthy Kids’ (HDHK) program, which was designed to help overweight fathers lose weight and be a role model of positive health behaviors for their children. Design: Randomized controlled trial. Participants: A total of 53 overweight/obese men (mean (s.d.) age=40.6 (7.1) years; body mass index (BMI)=33.2 (3.9)) and their primary school-aged children (n=71, 54% boys; mean (s.d.) age=8.2 (2.0) years) were randomly assigned (family unit) to either (i) the HDHK program (n=27 fathers, n=39 children) or (ii) a wait-list control group (n=26 fathers, n=32 children). Intervention: Fathers in the 3-month program attended eight face-to-face education sessions. Children attended three of these sessions. Outcomes: The primary outcome was fathers’ weight. Fathers and their children were assessed at baseline, and at 3- and 6-month follow-up, for weight, waist circumference, BMI, blood pressure, resting heart rate (RHR), objectively measured physical activity and self-reported dietary intake. Results: Intention-to-treat analysis revealed significant between-group differences at 6 months for weight loss (P<0.001), with HDHK fathers losing more weight (−7.6 kg; 95% confidence interval (CI) −9.2, −6.0; d=0.54) than control group fathers (0.0 kg; 95% CI −1.4, 1.6). Significant treatment effects (P<0.05) were also found for waist circumference (d=0.62), BMI (d=0.53), systolic blood pressure (d=0.92), RHR (d=0.66) and physical activity (d=0.91), but not for dietary intake. In children, significant treatment effects (P<0.05) were found for physical activity (d=0.74), RHR (d=0.51) and dietary intake (d=0.84). Conclusion: The HDHK program resulted in significant weight loss and improved health-related outcomes in fathers and improved eating and physical activity among children. Targeting fathers is a novel and efficacious approach to improving health behavior in their children. 2013-05-14T23:16:49.550Z ]]> 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:12879 Background: Childhood obesity is one of the most pressing health issues of our time. Key health organizations have recommended research be conducted on the effectiveness of well-designed interventions to combat childhood obesity that can be translated into a variety of settings. This paper describes the design and methods used in the Hunter Illawarra Kids Challenge Using Parent Support (HIKCUPS) trial, an ongoing multi-site randomized controlled trial, in overweight/obese children comparing the efficacy of three interventions: 1) a parent-centered dietary modification program; 2) a child-centered physical activity skill- development program; and 3) a program combining both 1 and 2 above. Methods/Design: Each intervention consists of three components: i) 10-weekly face-to-face group sessions; ii) a weekly homework component, completed between each face-to-face session and iii) three telephone calls at monthly intervals following completion of the 10-week program. Details of the programs' methodological aspects of recruitment, randomization and statistical analyses are described here a priori. Discussion: Importantly this paper describes how HIKCUPS addresses some of the short falls in the current literature pertaining to the efficacy of child obesity interventions. 2013-05-14T06:21:17.599Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:11865 The main aim of this study was to determine the test–retest reliability of existing tests of health-related fitness. Participants (mean age 14.8 years, s=0.4) were 42 boys and 26 girls who completed the study assessments on two occasions separated by one week. The following tests were conducted: bioelectrical impedance analysis (BIA) to calculate percent body fat, leg dynamometer, 908 push-up, 7-stage sit-up, and wall squat tests. Intra-class correlation (ICC), paired samples t-tests, and typical error expressed as a coefficient of variation were calculated. The mean percent body fat intra-class correlation coefficient was similar for boys (ICC=0.95) and girls (ICC=0.93), but the mean coefficient of variation was considerably higher for boys than girls (22.2% vs. 12.2%). The boys’ coefficients of variation for the tests of muscular fitness ranged from 9.0% for the leg dynamometer test to 26.5% for the timed wall squat test. The girls’ coefficients of variation ranged from 17.1% for the sit-up test to 21.4% for the push-up test. Although the BIA machine produced reliable estimates of percent body fat, the tests of muscular fitness resulted in high systematic error, suggesting that these measures may require an extensive familiarization phase before the results can be considered reliable. 2013-05-14T06:20:22.248Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:11858 The aim of this review was to evaluate the reliability and validity of methods used to assess the multiple components of sedentary behaviour (i.e. screen time, sitting, not moving and existing at low energy expenditure) in children and adolescents. Twenty-six studies met our inclusion criteria and were reviewed. Thirteen studies reported the reliability of self- and proxy-report measures of sedentary behaviour and seven of these were found to have acceptable test–retest reliability. Evidence for the criterion validity of self- and proxy-report measures was examined in three studies with mixed results. Seven studies examined the reliability and/or validity of direct observation and the findings were generally positive. Five studies demonstrated the utility of accelerometers to accurately classify sedentary behaviour. Self-report measures provide reliable estimates of screen time, yet their validity remains largely untested. While accelerometers can accurately classify participants’ behaviour as sedentary, they do not provide information about type of sedentary behaviour or context. Studies utilizing measures of sedentary behaviour need to more adequately report on the validity and reliability of the measures used. We recommend the use of objective measures of sedentary behaviour such as accelerometers, in conjunction with subjective measures (e.g. self-report), to assess type and context of behaviour. 2013-05-14T06:19:26.813Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:11850 Objective: To describe dietary changes in men participating in an obesity intervention as part of the Self-Help, Exercise and Diet using Information Technology (SHED-IT) study. Design: An assessor-blinded randomized controlled trial comparing Internet (n34)v.information-only groups (n31) with 6-month follow-up. Dietary intake assessed by FFQ, reporting usual consumption of seventy-four foods and six alcoholic beverages using a 10-point frequency scale. A single portion size (PSF) factor was calculated based on photographs to indicate usual serving sizes. Setting: The campus community of the University of Newcastle, New South Wales, Australia. Subjects: Sixty-five overweight/obese men (43% students, 42% non-academic general staff, 15% academic staff; mean age 35.9 (SD 11.1) years, mean BMI 30.6 (SD 2.8) kg/m²). Results: The average PSF decreased significantly over time (χ²=20.9, df=55, P<0.001) with no differences between groups. While both groups reduced mean daily energy intake (GLM χ²=34.5, df=3, P<0.001), there was a trend towards a greater reduction in the Internet group (GLM χ²=3.3, P=0.07). Both groups reduced percentage of energy from fat (P<0.05), saturated fat (P<0.001) and energy-dense/nutrient-poor items (P<0.05), with no change in dietary fibre or alcohol (P>0.05). Conclusions: Although men reported some positive dietary changes during weight loss, they did not increase vegetable intakes nor decrease alcohol consumption, while saturated fat, fibre and Na intakes still exceeded national targets. Future interventions for men should promote specific food-based guidelines to target improvements in their diet-related risk factor profile for chronic diseases. 2013-05-14T06:17:05.082Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:11864 Background: Physical activity declines during adolescence and strategies to combat this occurrence are both educational and public health priorities. Schools have been identified as central institutions for the promotion of physical activity among youth. While physical education is considered to be the major vehicle for physical activity promotion in the school setting, school sport provides another important opportunity to engage youth in physical activity. Little is known about students’ beliefs about the value of school sport. Purpose: The primary aim of this study was to explore the relationship between students’ beliefs about school sport, social support received during school sport and physical self-esteem in adolescents. Participants and setting: The sample included 249 adolescents (126 boys and 123 girls) from 10 secondary schools in New South Wales, Australia. The mean age of students was 14.1 (± 1.6) years. Research design: Cross-sectional. Data collection and analysis: Participants completed a detailed questionnaire assessing participation in school sport, school sport beliefs, perceived social support for school sport and physical self-esteem using the Physical Self-Perception Profile (PSPP). Independent samples t-tests were used to examine gender and age differences and hierarchical regression was used to determine the relationship between students’ school sport beliefs, social support received during school sport and physical selfesteem. Separate analyses were conducted for boys and girls. Findings: Both boys and girls considered school sport an important opportunity to be physically active. Students believed 'enjoyment’ and selecting activities with their friends were the most important reasons for selecting school sport activities. Boys reported significantly higher levels of perceived physical strength (F = 1.58, p < 0.05), sport competence (F = 0.28, p < 0.001), physical condition (F = 0.36, p < 0.01), body attractiveness (F = 1.76, p < 0.01), and physical self-worth (F = 3.32, p < 0.05). The model predicting boys’ beliefs about school sport explained 17% of the variance (F = 4.08, p < 0.01) and the only statistically significant predictor was school sport social support (β = 0.25, p < 0.01). Similarly, school sport social support (β = 0.31, p < 0.01) was also the only significant predictor in the girls’ model which accounted for 28% of the variance in school sport beliefs (F = 6.46, p < 0.001). Discussion: Students who recognised the value of school sport also reported higher levels of social support for school sport. School sport is an ideal opportunity for the promotion of physical activity and programs may be improved with increased diversity and choice for students. Furthermore, higher levels of teacher support and modelling may contribute to improved student outcomes for school sport programs. 2013-05-14T06:16:01.402Z ]]> 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:12459 Background: There is a paucity of information in the scientific literature on the effectiveness of commercial weight loss programs, including Web-based programs. The potential of Web-based weight loss programs has been acknowledged, but their ability to achieve significant weight loss has not been proven. Objective: The objectives were to evaluate the weight change achieved within a large cohort of individuals enrolled in a commercial Web-based weight loss program for 12 or 52 weeks and to describe participants’ program use in relation to weight change. Method: Participants enrolled in an Australian commercial Web-based weight loss program from August 15, 2007, through May 31, 2008. Self-reported weekly weight records were used to determine weight change after 12- and 52-week subscriptions. The primary analysis estimated weight change using generalized linear mixed models (GLMMs) for all participants who subscribed for 12 weeks and also for those who subscribed for 52 weeks. A sensitivity analysis was conducted using the last observation carried forward (LOCF) method. Website use (ie, the number of days participants logged on, made food or exercise entries to the Web-based diary, or posted to the discussion forum) was described from program enrollment to 12 and 52 weeks, and differences in website use by percentage weight change category were tested using Kruskal-Wallis test for equality of populations. Results: Participants (n = 9599) had a mean (standard deviation [SD]) age of 35.7 (9.5) years and were predominantly female (86% or 8279/9599) and obese (61% or 5866/9599). Results from the primary GLMM analysis including all enrollees found the mean percentage weight change was −6.2% among 12-week subscribers (n = 6943) and −6.9% among 52-week subscribers (n = 2656). Sensitivity analysis using LOCF revealed an average weight change of −3.0% and −3.5% after 12 and 52 weeks respectively. The use of all website features increased significantly (P < .01) as percentage weight change improved. Conclusions: The weight loss achieved by 12- and 52-week subscribers of a commercial Web-based weight loss program is likely to be in the range of the primary and sensitivity analysis results. While this suggests that, on average, clinically important weight loss may be achieved, further research is required to evaluate the efficacy of this commercial Web-based weight loss program prospectively using objective measures. The potential association between greater website use and increased weight loss also requires further evaluation, as strategies to improve participants’ use of Web-based program features may be required. 2013-05-13T04:48:35.535Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12446 Optimal dietary quality, indicated by higher diet quality index scores, reflects greater adherence to National dietary recommendations and is also associated with lower morbidity and mortality from chronic disease. Whether this is reflected in lower health care cost over time has rarely been examined. The aim of this study was to examine whether higher diet quality, as measured by the Australian Recommended Food Score (ARFS), was associated with lower health care costs within the mid-aged cohort of the Australian Longitudinal Study on Women’s Health. We found that there was a statistically significant association between five year cumulative costs and ARFS, but in the opposite direction to that predicted, with those in the highest quintiles of ARFS having higher health care costs. However the number of Medicare claims over the six year period (2002–2007) was lower for those in the highest compared with the lowest quintile, p = 0.002. There is a need to monitor both costs and claims over time to examine health care usage in the longer term in order to determine whether savings are eventually obtained for those with the dietary patterns that adhere more closely to National recommendations. 2013-05-13T04:47:32.384Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12426 Background: Preconception and pregnancy dietary intakes can influence the health of future generations. In this study we compared the food intakes of reproductive-aged women by pregnancy status, to current Australian recommendations. Methods: Data are from the Australian Longitudinal Study on Women's Health, younger cohort aged 25-30 years in 2003, with self-reported status as pregnant (n = 606), trying to conceive (n = 454), given birth in the last 12 months (n = 829) or other (n = 5597). 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 (AGHE) and Australian Nutrient Reference Values (NRVs). Results: No women met all AGHE food group recommendations. Highest adherence rates [mean (95% CI) servings/day] were for meat [85%, 1.9(1.8-1.9)], fruit [44%, 2.1(2.1-2.2)] and dairy [35%, 1.8(1.8-1.9)], with < 14% meeting remaining recommendations. Women who achieved NRVs (folate, iron, calcium, zinc, fibre) for pregnancy, breastfeeding and adult life stages were 1.5%, 3.3% and 13.7%, respectively. Compared to AGHE, women consumed more servings of fruit (4.9 vs 4.0;P = 0.034) and dairy (3.4 vs 2.0;P = 0.006) to achieve pregnancy NRVs; more dairy (2.9 vs 2.0;P = 0.001), less fruit (3.9 vs 5.0;P < .001) and vegetables (3.4 vs 7.0;P < .001) to achieve breastfeeding NRVs; more fruit (3.6 vs 3.0;P < .001), dairy (2.5 vs 2.0;P < .001), meat (1.8 vs 1.5;P = 0.015), less vegetables (3.6 vs 5.0;P < .001) to achieve adult NRVs. Conclusions: The AGHE does not align with contemporary diets of Australian women or enable them to meet all NRVs. Current tools to guide food consumption by women during pregnancy require revision. 2013-05-13T04:46:20.455Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:9448 Background: An understanding of the factors that predict retention and website use are critical to the development of effective Web-based weight loss interventions. However, poor retention (dropout attrition) and website utilization (nonusage attrition) are major inhibitors to the effectiveness of Web-based programs. Objective: The study aimed to (1) describe the prevalence of dropout and nonusage attrition and (2) examine pretreatment predictors of nonusage attrition in a cohort of commercial Web-based weight loss program participants. Methods: Participants enrolled in the online program, The Biggest Loser Club, Australia, from August 15, 2007, to May 31, 2008. Only those who subscribed for 12 or 52 weeks were included in this study. All data were collected by the program proprietors, SP Health Co Pty Ltd (Sydney, Australia), and provided in “deidentified” form. Data collected included responses to a pretreatment survey (sociodemographic and behavioral characteristics), subscription history (date of enrollment and subscription end), and website use (log-ins, food and exercise diary entries, weigh-ins, and forum posts). Participants were classified as a member of the program at 12 or 52 weeks if they held an active subscription plan at that point in time. Participants were classified as nonusers at 12 or 52 weeks if they had stopped using all of the website features and had not returned. Predictors of nonusage attrition were explored using Cox proportional hazards regression analysis. Results: Of the 9599 eligible participants, 6943 (72%) subscribed to the program for 12 weeks, and 2656 (28%) subscribed for 52 weeks. Of all participants, 31% (2975/9599) were classified as overweight, 61% (5866/9599) were classified as obese, 86% (8279/9599) were female, and participants’ mean (SD) age was 35.7 (9.5) years. The 12 week and 52 week subscribers’ retention rates were 97% and 77% respectively. Of 12 week subscribers, 35% were classified as program “users” after 12 weeks, and 30% of 52 week subscribers were classified as “users” after 52 weeks. Significant predictors of nonusage attrition among 12 week subscribers included age (hazard ratio for 45 to 55 years of age = 0.83, 95% confidence interval [CI] 0.73 - 0.93, P = .001; hazard ratio for 55 to 65 years of age = 0.80, 95% CI 0.66 - 0.99, P = .04), exercise level (hazard ratio = 0.76, 95% CI 0.72 - 0.81, P < .001), emotional eating (hazard ratio = 1.11, 95% CI 1.04 - 1.18, P = .001), eating breakfast (hazard ratio = 0.88, 95% CI 0.82 - 0.95, P = .001), and skipping meals (hazard ratio = 1.12, 95% CI 1.04 -1.19, P = .001). For 52 week subscribers, eating breakfast (hazard ratio = 0.88, 95% CI 0.79 - 0.99, P = .04) and not drinking tea or coffee with sugar (hazard ratio = 1.23, 95% CI 1.11 - 1.37, P < .001) were the pretreatment characteristics that significantly decreased risk of nonusage attrition. Conclusions: The findings demonstrate a high prevalence of nonusage attrition among a cohort of commercial Web-based weight loss program participants. Several sociodemographic and behavioral factors were shown to independently predict nonusage attrition. 2013-05-13T04:43:41.547Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:9446 Background: Obesity rates in adults continue to rise and effective treatment programs with a broad reach are urgently required. This paper describes the study protocol for a web-based randomized controlled trial (RCT) of a commercially available program for overweight and obese adult males and females. The aim of this RCT was to determine and compare the efficacy of two web-based interventions for weight loss and maintenance of lost weight. Methods/Design: Overweight and obese adult males and females were stratified by gender and BMI and randomly assigned to one of three groups for 12-weeks: waitlist control, or basic or enhanced online weight-loss. Control participants were re-randomized to the two weight loss groups at the end of the 12-week period. The basic and enhanced group participants had an option to continue or repeat the 12-week program. If the weight loss goal was achieved at the end of 12, otherwise on completion of 24 weeks of weight loss, participants were re-randomized to one of two online maintenance programs (maintenance basic or maintenance enhanced), until 18 months from commencing the weight loss program. Assessments took place at baseline, three, six, and 18 months after commencing the initial weight loss intervention with control participants repeating the initial assessment after three month of waiting. The primary outcome is body mass index (BMI). Other outcomes include weight, waist circumference, blood pressure, plasma markers of cardiovascular disease risk, dietary intake, eating behaviours, physical activity and quality of life. Both the weight loss and maintenance of lost weight programs were based on social cognitive theory with participants advised to set goals, self-monitor weight, dietary intake and physical activity levels. The enhanced weight loss and maintenance programs provided additional personalized, system-generated feedback on progress and use of the program. Details of the methodological aspects of recruitment, inclusion criteria, randomization, intervention programs, assessments and statistical analyses are described. Discussion: Importantly, this paper describes how an RCT of a currently available commercial online program in Australia addresses some of the short falls in the current literature pertaining to the efficacy of web-based weight loss programs. 2013-05-13T04:24:20.385Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:9374 Background: Obesity is a major cause of preventable death in Australia with prevalence increasing at an alarming rate. Of particular concern is that approximately 68% of men are overweight/obese, yet are notoriously difficult to engage in weight loss programs, despite being more susceptible than women to adverse weight-related outcomes. There is a need to develop and evaluate obesity treatment programs that target and appeal to men. The primary aim of this study is to evaluate the efficacy of two relatively low intensity weight loss programs developed specifically for men. Methods and Design: The study design is an assessor blinded, parallel-group randomised controlled trial that recruited 159 overweight and obese men in Newcastle, Australia. Inclusion criteria included: BMI 25-40 (kg/m2); no participation in other weight loss programs during the study; pass a health-screening questionnaire and pre-exercise risk assessment; available for assessment sessions; access to a computer with e-mail and Internet facilities; and own a mobile phone. Men were recruited to the SHED-IT (Self-Help, Exercise and Diet using Internet Technology) study via the media and emails sent to male dominated workplaces. Men were stratified by BMI category (overweight, obese class I, obese class II) and randomised to one of three groups: (1) SHED-IT Resources - provision of materials (DVD, handbooks, pedometer, tape measure) with embedded behaviour change strategies to support weight loss; (2) SHED-IT Online - same materials as SHED-IT Resources plus access to and instruction on how to use the study website; (3) Wait-list Control. The intervention programs are three months long with outcome measures taken by assessors blinded to group allocation at baseline, and 3- and 6-months post baseline. Outcome measures include: weight (primary outcome), % body fat, waist circumference, blood pressure, resting heart rate, objectively measured physical activity, self-reported dietary intake, sedentary behaviour, physical activity and dietary cognitions, sleepiness, quality of life, and perceived sexual health. Generalised linear mixed models will be used to assess all outcomes for the impact of group (Resources, Online, and Control), time (treated as categorical with levels baseline, 3-months and 6-months) and the group-by-time interaction. These three terms will form the base model. 'Intention-to-treat' analysis will include all randomised participants. Discussion: Our study will compare evidence-based and theoretically driven, low cost and easily disseminated strategies specifically targeting weight loss in men. The SHED-IT community trial will provide evidence to inform development and dissemination of sustainable strategies to reduce obesity in men. 2013-05-13T04:22:20.893Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:7257 Measures of diet quality have evolved with a number of scoring indices currently in use. They are increasingly being used to examine epidemiological associations between dietary intake and nutrition-related health outcomes. The present review aims to describe current diet quality tools and their applications, and to examine the relationship between diet quality and morbidity and mortality. A search was conducted of MEDLINE, Cochrane, EMBASE, CINAHL and ProQuest electronic databases. Inclusion criteria were: English language; published from 2004 on; conducted in adult populations; longitudinal/cohort/case–control or cross-sectional study; included a theoretically defined measure of diet quality. A total of twenty-five indices of overall diet quality and/or variety were found, with components ranging from nutrients only to adherence to recommended food group servings, to variety within healthful food groups. The majority of studies reviewed had methodological weaknesses but demonstrated that higher dietary quality was consistently inversely related to all-cause mortality, with a protective effect of moderate magnitude. The associations were stronger for men and for all-cause and CVD mortality. The limitations of both the indices and the studies that use them need to be considered when interpreting and comparing results. However, diet quality indices do appear to be able to quantify risk of some health outcomes, including biomarkers of disease and risk of CVD, some cancers and mortality. Further research is needed to improve the validity of these tools and to adapt them for use in clinical dietetic practice. 2013-05-13T04:18:38.821Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:7737 Dietary intake during childhood and adolescence is of increasing interest due to its influence on adult health, particularly obesity, cardiovascular disease and diabetes. There is a need to develop and validate dietary assessment methods suitable for large epidemiologic studies of children and adolescents. Limited large scale dietary studies of youth have been undertaken in Australia, due partly to the lack of a suitable dietary intake tool. A self-administered, semi-quantitative food-frequency questionnaire (FFQ), the 'Australian Child and Adolescent Eating Survey' (ACAES), was developed for youth aged 9-16 years. This study evaluated reproducibility and comparative validity of the ACAES FFQ using assisted food records (FRs) as the reference method. The ACAES FFQ was completed twice (FFQ1 and FFQ2) at an interval of 5 months, along with four one-day assisted FRs. Validity was evaluated by comparing the average of the FRs with FFQ2 (n = 113) as well as with the average of FFQ1 and FFQ2 (n = 101). Reproducibility was evaluated by comparing FFQ1 and FFQ2 (n = 101). The two methods were compared using correlations, Kappa statistics and Bland-Altman plots. Correlation coefficients for comparative validity ranged from 0.03 for retinol to 0.56 for magnesium for transformed, energy-adjusted, deattenuated nutrient data, with correlation coefficients greater than 0.40 for total fat, saturated fat, monounsaturated fat, carbohydrate, sugars, riboflavin, vitamin C, folate, beta-carotene, magnesium, calcium and iron. Correlation coefficients for reproducibility ranged from 0.18 for vitamin A to 0.50 for calcium for transformed, energy-adjusted, deattenuated nutrient data. The ACAES FFQ ranked individuals reasonably accurately, with the comparative validity analysis showing that over 50% of participants were classified within one quintile for all nutrients, with only a small percentage grossly misclassified (0-7%). The ACAES FFQ is the first child and adolescent specific FFQ available for ranking the dietary intakes of Australian children and adolescents for a range of nutrients in epidemiologic research and public health interventions. 2013-05-13T04:16:32.266Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:10468 Background: Effective treatment of childhood obesity requires a multi-factorial approach and should target factors impacting on a child's environment. Objective: To explore the impact of three treatment programs on parental child-feeding practices at 6, 12 and 24 months post-program. Subjects/Intervention. Overweight children (n=159) aged 5–7 years, recruited to the Hunter Illawarra Kids Challenge Using Parent Support (HIKCUPS) randomized controlled trial with three treatment arms; a dietary modification program, a physical activity skill development program or a combination of both programs. Main outcome measures: The Child Feeding Questionnaire (CFQ), a validated 31-item questionnaire measuring child-feeding practices, completed by parents. Statistical analysis. Linear mixed models were used to assess change over time and to determine differences by intervention group. Results: A significant decrease (p<0.01) in CFQ domain scores were reported and sustained at 24 months for all groups, in the domain of pressure to eat (mean±SEM, 1.8±0.06, 1.6±0.06) with increases in degree of monitoring (4.0±0.07, 4.2±0.06). The domain of restriction showed significant decreases in dietary intervention groups only (baseline 3.9±0.05, 24 months 3.7±0.06), the domain scores for concern were found to be strongly associated with child BMI z-score (r=0.73, p < 0.001) at baseline only. Conclusions: This study provides evidence that specific child-feeding domains are modifiable in the context of a targeted obesity intervention and further that changes can be sustained over time. 2013-05-13T03:26:28.432Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:11501 Measuring dietary intake in children enables the assessment of nutritional adequacy of individuals and groups and can provide information about nutrients, including energy, food, and eating habits. The aim of this review was to determine which dietary assessment method(s) provide a valid and accurate estimate of energy intake by comparison with the gold standard measure, doubly labeled water (DLW). English-language articles published between 1973 and 2009 and available from common nutrition databases were retrieved. Studies were included if the subjects were children birth to age 18 years and used the DLW technique to validate reported energy intake by any other dietary assessment method. The review identified 15 cross-sectional studies, with a variety of comparative dietary assessment methods. These included a total of 664 children, with the majority having <30 participants. The majority of dietary assessment method validation studies indicated a degree of misreporting, with only eight studies identifying this to a significant level (P<0.05) compared to DLW estimated energy intake. Under-reporting by food records varied from 19% to 41% (n=5 studies) with over-reporting most often associated with 24-hour recalls (7% to 11%, n=4), diet history (9% to 14%, n=3), and food frequency questionnaires (2% to 59%, n=2). This review suggested that the 24-hour multiple pass recall conducted over at least a 3-day period that includes weekdays and weekend days and uses parents as proxy reporters is the most accurate method to estimate total energy intake in children aged 4 to 11 years, compared to total energy expenditure measured by DLW. Weighed food records provided the best estimate for younger children aged 0.5 to 4 years, whereas the diet history provided better estimates for adolescents aged ≥16 years. Further research is needed in this area to substantiate findings and improve estimates of total energy expenditure in children and adolescents. 2013-05-13T01:54:15.575Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12874 Over the past 25 years, the Australian workforce has become more casualised, with approximately one-quarter of the workforce in casual employment today. One of the highest users of casual employees is the higher education sector, where casual academics (referred to as sessionals in the Australian context) are estimated to account for 50% of the overall teaching load. The purpose of this article is to investigate the processes associated with the management of sessional academic staff. The study focuses on a single university, utilising a survey questionnaire and interviews with the sessional academics and their managers. The results depict a bifurcated system of maximum labour regulation for full-time academics alongside minimum regulation for sessional staff. The findings stress the urgency for improvement in both the employment conditions and management of sessional academic staff, both for their own benefit and the universities that employ them. 2013-05-12T23:49:01.735Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12867 Objective: To identify sources of food eaten during the school day, the types of foods and frequency of purchases from the canteen and association with SES and weight status in primary school-aged children. Method: This cross-sectional study was conducted in the Hunter region of New South Wales. Primary schools were randomly selected from a list of government schools and 5,206 students in years 1–6 from the 16 participating schools were invited to participate in the study. Results: Findings show the majority of children in the study bring their recess snack and lunch from home. However, the majority of children do use the school canteen and less healthy foods and highsugar drinks are commonly purchased. Conclusions: This study confirms the relevance of the school canteen as a means of affecting children's eating habits. Implications: Improvement in the foods sold through schools provides an important contribution to model supportive environments for healthy food choices. Strategies should also be directed towards affecting the content of lunchboxes and the home environment. 2013-05-09T06:17:14.378Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12866 Objective: To describe the development and reproducibility of a self-report instrument, for use with children in years 4–6, to identify sources of food eaten during the day, and type and frequency of food purchases at school. Design: Tool development stages included formulation of content and format, expert review, piloting and a test–retest study. Subjects/setting: The pilot study included school students (n = 20) in years 4 and 5 (seven girls, mean age 9.7 ± 0.7 years) attending an Australian public primary school. The test–retest study was performed in a large metropolitan public primary school (n = 245 children, 52% female, mean age 10.7 ± 0.91 years) including children from years 4 (n = 88), 5 (n = 84) and 6 (n = 73). Statistical analysis: A Kappa statistic was used to assess level of agreement between the two time periods separated by 1 week. The results were analysed using SAS version 8.2 with each question compared at time 1 and 2. Results: The mean kappa was 0.529 using pairings from 17 questions. Values ranged from 0.18 to 0.71 (CI 0.46–0.60). Conclusions and applications: The School Eating Habits and Lifestyle Survey has been developed and pilot-tested in primary school-aged children and shown to have moderate stability over time. The results show that each phase of development, particularly those spent in consultation and testing, led to progressive improvement of this instrument. This process improved the quality of information produced and gave insights to self-report of dietary intake and behaviours among children. 2013-05-09T06:15:44.363Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12865 Background: The prevalence of overweight and obesity in children and adolescents is increasing at an alarming rate around the world and prevention has become a key public health objective. Treatment and management of those already overweight and obese must be aligned with the best available evidence on effectiveness, if the risk of obesity-related morbidity and mortality is yet be reduced. Diet plays a pivotal role in successful treatment of obesity but to date, there is limited evidence on which to base practice. Objectives: To identify and present the best available evidence on the optimal dietetic treatment and management of children and adolescent who are overweight or obese. Search strategy: Published English language literature was searched using the electronic databases CINAHL, MEDLINE, PRE-MEDLINE, DARE, COCHRANE, EMBASE, AUSTROM, Current Concepts and Dissertation Abstracts. The databases were limited to English Language from 1975 until 2003. Government reports from the UK, USA and Australian were also searched and a hand search performed for the Journal of the Dietitians Association of Australia, International Journal of Obesity and the Journal of Human Nutrition and Dietetics and the bibliographies of retrieved articles. Selection criteria: (i) Interventions that evaluated the effectiveness of nutrition or dietary interventions to treat or manage overweight and obesity; (ii) Children aged less than 18 years; and (iii) Participants were defined as overweight or obese by relative weight or a measure of body weight status, studies that reported body weight per se were excluded. Data collection and analysis: An experienced professional librarian searched the databases, and two trained research assistants independently identified studies for retrieval and assessed each article for inclusion. The included studies were critically appraised for methodological quality by two people independently. Data were extracted from the appropriate articles and when a discrepancy arose, a third party would arbitrate. Main results: There were 116 articles that met the inclusion criteria. While 49 articles described randomised controlled trials, they arose from 37 separate studies. There were 67 non-randomised trials. Meta-analyses were performed on eight studies that included both a dietary intervention component and an adequate control group and on four studies that had follow-up data. There was a high degree of heterogeneity between studies and this made comparisons between studies problematic. Interventions that include diet therapy generally result in significant weight loss, at least in the short term. Many studies were poorly designed and had no or only minimal follow up. The details of the dietary intervention were often inadequately described and dietary outcomes rarely reported, making repetition of the studies difficult. Reviewers’ conclusions: There is an urgent need for high quality studies investigating the optimal dietary approach to management of paediatric overweight and obesity. These studies require adequate follow up to ascertain if weight loss can be sustained in the long term. Details of the dietary prescription, adherence to the dietary intervention and diet-specific outcomes need to be reported in order to inform best practice. 2013-05-09T06:14:50.885Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12864 Objective: To describe wellbeing and nutrition-related side effects in a group of paediatric oncology patients undergoing chemotherapy, and to examine associations with nutritional status, disease and treatment-related factors. Methods: Cross-sectional survey of patients attending the Sydney (n = 41) or John Hunter Children’s Hospitals (n = 13). Wellbeing was assessed using the Multi-attribute Health Status Classification Scheme (MHSCS) and the Play Performance Scale (PPS). Disease and treatment details were obtained through patient and parent interviews and audit of medical records. Nutritional status was assessed using anthropometric and biochemical measurements. Results: Twenty-four per cent and 33% scored maximum points on the MHSCS and PPS, respectively. Advanced stage of solid tumour or lymphoma was associated with worse MHSCS scores, P = 0.008. Longer time on treatment correlated negatively with PPS scores (r = −0.35; P = 0.030). The most frequent side effects were nausea, decreased appetite, vomiting and changes in taste. While 67% experienced five or more side effects concurrently, the number increased with length of time on treatment (r = 0.38; P = 0.006). Of the 23 patients experiencing five or more side effects, only two had been seen by a dietitian in the previous two months. Conclusion: Nutrition-related side effects are common in children undergoing chemotherapy, with the number of side effects not decreasing over time. While wellbeing scores were generally satisfactory, those with advanced stage of solid tumour or lymphoma, or with longer time on treatment, reported lower scores. We recommend that all paediatric oncology patients are referred for dietetic review, even those in the later stages of treatment, in order to optimise nutritional status and wellbeing. 2013-05-09T06:13:59.330Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12863 This cross-sectional study describes oxidative stress and antioxidant status in 54 pediatric oncology patients undergoing chemotherapy. Plasma 8-iso-prostaglandin-F2α(8-iso-PGF2α), vitamins A and E and β-carotene, and erythrocyte activities of superoxide dismutase and glutathione peroxidase levels were assessed. One-third of the patients (34%) had plasma 8-iso-PGF2α levels higher than the upper limit of the normal range (> 40 ng/mL). The majority (> 80%) had plasma levels of vitamins A and E and β-carotene within the normal range. Superoxide dismutase activity was lower than the reference range (< 2.4 U/mg Hb) in all patients, whereas erythrocyte glutathione peroxidase activity was lower than the reference range in 46%. Advanced-stage cancer was associated with increased lipid peroxidation but treatment-related factors or use of dietary supplements was not, suggesting that the oxidant-antioxidant balance may be disturbed in a large proportion of this group. Prospective studies would establish whether antioxidant supplementation plays a role in clinical treatment for pediatric oncology patients. 2013-05-09T06:13:02.319Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12862 Background: Malnutrition among elderly hospitalised patients is widespread and has been shown to lead to adverse health outcomes. The effectiveness of interventions to minimise undernutrition in elderly inpatients is not well documented. Objectives: To identify the best available practices, in the hospital setting, that minimise undernutrition or the risk of undernutrition, in the acute care patient especially for the older patient. The review will assesses the effectiveness of a range of interventions designed to promote adequate nutritional intake in the acute care setting, with the aim of determining what practices minimise malnutrition in the elderly inpatients. Search strategy: English language articles from 1980 onwards were sought using Medline, Premedline, Cinahl, Austrom-Australasian Medical Index and AustHealth, Embase and Science Citations Index. Selection criteria: For inclusion the study had to include an intervention aiming to minimise undernutrition in hospitalised elderly patients aged 65 years or older. All study designs were included. Data collection and analysis: Two independent reviewers assessed the eligibility of each study for inclusion into the review, critically appraised the study quality and extracted data using standardised tools. For each outcome measure results were tabulated by intervention type and discussed in a narrative summary. Results from randomised controlled trials were pooled in meta-analyses where appropriate. Main results: Twenty-nine studies met the inclusion criteria, with a total of 4021 participants. The focus of 15 interventions was the supplying of oral supplements to the participants, six focused on enteral nutrition therapy, four interventions made changes to the foods provided as part of the hospital diet, one included the services of an additional staff member and three incorporated the implementation of evidence-based guidelines. Ten metaanalyses were conducted from which the main findings were: significant improvements in weight status and arm muscle circumferences with an oral supplement intervention, P < 0.05. Reviewers’ conclusions: The findings of the review support the use of oral supplements to minimise undernutrition in elderly inpatients. The results also emphasise the need for more high-quality research using appropriate outcome measures in the area of minimisation of undernutrition, particularly interventions that make alterations to the hospital diet and address support for feeding patients at the ward level. 2013-05-09T06:11:53.048Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12861 Aims: Patients with oesophageal cancer undergoing chemoradiation with curative intent are at high risk of malnutrition and its complications, including increased side effects of treatment. We have developed a nutrition pathway (NP), involving the early then periodic nutrition assessment of all patients presenting to the multidisciplinary oesophageal clinic who were planned to receive definitive chemoradiation. Materials and methods: Patients were assessed as at ‘low’, ‘moderate’ or ‘severe’ nutrition risk, and were provided with appropriate nutrition intervention ranging from preventative advice (low risk), oral nutrition support (moderate risk) to enteral feeding (severe risk). Outcomes for 24 patients treated before implementation of the NP were compared with those of 24 patients treated using the NP. Results: Patients managed using the NP experienced less weight loss (mean weight change −4.2 kg ±6.4 cf. −8.9 kg ±5.9, P = 0.03), greater radiotherapy completion rates (92% cf. 50%, P = 0.001), fewer patients had an unplanned hospital admission (46% cf. 75%, P = 0.04), and those that did had a shorter length of stay (3.2 days ±5.4 cf. 13.5 days ±14.1, P = 0.002). Conclusion: Early and regular nutrition assessment/intervention and a multidisciplinary approach to nutrition care results in improved treatment tolerance for patients with oesophageal cancer receiving chemoradiation. 2013-05-09T06:10:44.386Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12860 Aim: To highlight and discuss the practical aspects of conducting high quality, randomised controlled trials (RCTs) with overweight and obese children and their families. Content: Realistic considerations and suggestions for researchers arising from the experiences of three Australian interventions in overweight/obese children are highlighted. The practical implications of key issues arising during this type of RCT include study design, obtaining ethical approval, choice of outcome measures, recruitment, working with families, impact and process evaluation, retention strategies, managing multisite trials and data management. Conclusion: Interventions for overweight children and their families are challenging. Although there were some differences in the design and outcome measures among the three studies, there were many similarities. Multi-site trials, although more expensive than single-site trials, are advantageous in increasing sample size and external validity. Collectively we have developed strategies to address key problems in conducting RCTs, including the common challenges of recruitment, retention and working with families. 2013-05-09T06:09:36.422Z ]]> 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:12856 Nonparametric analysis for general block designs can be given by using the Cochran-Mantel-Haenszel (CMH) statistics. We demonstrate this with four examples and note that several well-known nonparametric statistics are special cases of CMH statistics. 2013-05-09T03:24:17.486Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12858 We develop a test for equality of variances given two independent random samples of observations. The test can be expected to perform well when both sample sizes are at least moderate and the sample variances are asymptotically equivalent to the maximum likelihood estimators of the population variances. The test is motivated by and is here assessed for the case when both populations sampled are assumed to be normal. Popular choices of test would be the two-sample F test if normality can be assumed and Levene’s test if this assumption is dubious. Another competitor is the Wald test for the difference in the population variances.We give a nonparametric analogue of this test and call it the R test. In an indicative empirical study when both populations are normal, we find that when both sample sizes are at least 25 the R test is nearly as robust as Levene’s test and nearly as powerful as the F test. 2013-05-09T03:04:24.183Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:4742 We consider testing for an unobservable normal distribution with unspecified mean and variance. It is only possible to observe the counts in groups with boundaries specified before sighting the data. On the basis of a small power study, we recommend the usual X² test be used as an omnibus test, augmented by informal examination of the first two non-zero components of X². We also recommend use of maximum likelihood and method of moments estimation. 2013-05-09T01:41:12.197Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:10602 Tests based on the Anderson–Darling statistic, a third moment statistic and the classical Pearson–Fisher X² statistic, along with its third-order component, are considered. A small critical value and power study are given. Some examples illustrate important applications. 2013-05-09T01:25:50.270Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:7154 Correlation is often used to assess both independence and linearity in two dimensions, but is not well understood in higher dimensions. Here we take a closer look at these uses of correlation in two dimensions and how these assessments might be extended to higher dimensions. Our discussion will focus on the simple case of understanding the nature of correlation for association models for two- and three-way contingency tables, but can also be considered in a more general setting. 2013-05-09T01:02:39.324Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:5419 Tests for the Laplace distribution based on the sample skewness and kurtosis coefficients are shown to be related to components of smooth tests of goodness of fit and are compared with a number of tests including the Anderson-Darling test, a new data-driven smooth test, a new empirical characteristic function based test and a new maximum entropy test. This last would be our slight preference as the test of choice for testing for the Laplace distribution. 2013-05-09T00:47:49.876Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:4369 Smooth tests for the logarithmic distribution are compared with three tests: the first is a test due to Epps and is based on a probability generating function, the second is the Anderson-Darling test, and the third is due to Klar and is based on the empirical integrated distribution function. These tests all have substantially better power than the traditional Pearson-Fisher X² test of fit for the logarithmic. These traditional chi-squared tests are the only logarithmic tests of fit commonly applied by ecologists and other scientists. 2013-05-08T23:21:51.106Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:7914 For at least partially ordered three-way tables, it is well known how to arithmetically decompose Pearson's X²p statistic into informative components that enable a close scrutiny of the data. Similarly well-known are smooth models for two-way tables from which score tests for homogeneity and independence can be derived. From these models, both the components of Pearson's X²p and information about their distributions can be derived. Two advantages of specifying models are first that the score tests have weak optimality properties and second that identifying the appropriate model from within a class of possible models gives insights about the data. Here, smooth models for higher-order tables are given explicitly, as are the partitions of Pearson's X²p into components. The asymptotic distributions of statistics related to the components are also addressed. 2013-05-08T23:20:41.527Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:11212 The generalised score and Wald tests are described and related to their nongeneralised versions. Two interesting applications are discussed. In the first a new test for the Behrens-Fisher problem is derived. The second is testing homogeneity of variances from multiple univariate normal populations. 2013-05-08T23:19:34.946Z ]]> http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:12233 In this note two easily applied moment tests of the Rayleigh hypothesis are compared with the Anderson-Darling test, some smooth tests and tests based on the empirical Laplace transform. 2013-05-08T23:00:59.291Z ]]>