Boosting Monte Carlo simulations of spin glasses using autoregressive neural networks

The autoregressive neural networks are emerging as a powerful computational tool to solve relevant problems in classical and quantum mechanics. One of their appealing functionalities is that, after they have learned a probability distribution from a dataset, they allow exact and efficient sampling of typical system configurations. Here we employ a neural autoregressive distribution estimator (NADE) to boost Markov chain Monte Carlo (MCMC) simulations of a paradigmatic classical model of spin-glass theory, namely the two-dimensional Edwards-Anderson Hamiltonian. We show that a NADE can be trained to accurately mimic the Boltzmann distribution using unsupervised learning from system configurations generated using standard MCMC algorithms. The trained NADE is then employed as smart proposal distribution for the Metropolis-Hastings algorithm. This allows us to perform efficient MCMC simulations, which provide unbiased results even if the expectation value corresponding to the probability distribution learned by the NADE is not exact. Notably, we implement a sequential tempering procedure, whereby a NADE trained at a higher temperature is iteratively employed as proposal distribution in a MCMC simulation run at a slightly lower temperature. This allows one to efficiently simulate the spin-glass model even in the low-temperature regime, avoiding the divergent correlation times that plague MCMC simulations driven by local-update algorithms. Furthermore, we show that the NADE-driven simulations quickly sample ground-state configurations, paving the way to their future utilization to tackle binary optimization problems.Comment: 13 pages, 14 figure

Dietary patterns and diet quality : approaches to assessing complex exposures in nutrition

Dietary pattern analysis provides a practical way to characterise total diet. In contrast to single food approaches, measures of dietary patterns capture interactions between food components and assist in the development of food guidelines from a public health perspective. Two main approaches to assessing dietary patterns, multivariate statistical approach and dietary indices or scores in epidemiological studies, are assessed.<br /

The Regulation of Maize Leaf Phosphoenolpyruvate Carboxylase

When this project started, it had been shown that the PEP carboxylase of CAM plants was regulated by a reversible phosphorylation. The main aim of this work was therefore to examine the hypothesis that PEP carboxylase from maize leaves was regulated by phosphorylation in response to light or darkness

Does diet mediate associations of volume and bouts of sedentary time with cardiometabolic health indicators in adolescents?

Objective: Examine the mediating role of diet in the relationship between volume and duration of sedentary time with cardiometabolic health in adolescents. Methods: Adolescents (12-19 years) participating in the 2003/04 and 2005/06 U.S. National Health and Nutrition Examination Survey (NHANES) were examined. Cardiometabolic health indicators were body mass index z-scores (zBMI) (n 5 1,797) and metabolic syndrome (MetS) (n 5 812). An ActiGraph hip-worn accelerometer was used to derive total sedentary time and usual sedentary bout duration. Dietary intake was assessed using two 24-hour dietary recalls. Mediation analyses were conducted to examine five dietary mediators [total energy intake, discretionary foods, sugar-sweetened beverages (SSB), fruits and vegetables, and dietary quality] of the relationship between total sedentary time and usual sedentary bout duration with zBMI and MetS. Results: Total sedentary time was inversely associated with zBMI (b 5 21.33; 95% CI 22.53 to 20.13) but attenuated after adjusting for moderate-to-vigorous physical activity. No significant associations were observed between usual sedentary bout duration with zBMI or either sedentary measure with MetS. None of the five dietary variables mediated any of the relationships examined. Conclusions: Further studies are needed to explore associations of specific time periods (e.g., after school) and bout durations with both cardiometabolic health indicators and dietary behaviors

Gender and Stress Related Effects on Cardiovascular Health Outcomes

Title[j1] : Gender and stress related effects on cardiovascular health outcomes Authors: Michael Cedeño – Master’s, (Tarleton State University), Jennifer Blevins-McNaughton (Tarleton State University) Background and Purpose: To date, only a few investigators have compared the effect that stress may have on health and metabolic outcomes in college age adults. The purpose of this study was to determine the extent to which gender may play a role in self-reported stress and cardiovascular and metabolic outcomes in college age students. Methods: Thirty-eight (N = 38) adults ages 18 to 28 participated in this study. Height, weight, supine resting heart rate and supine blood pressure were measured. Subjects completed the Institute of HeartMath® Stress and Well-Being Survey™ to measure psychological stressors, total stress score, total well-being, and emotional vitality. Total blood cholesterol, HDL, LDL, triglycerides, TC/HDL ratio, and glucose were measured in a randomly selected subset of 13 subjects (N = 13; 7 females and 6 males) using the Cholestech LDX®. Independent t-test and Pearson correlations were used to analyze differences between male and female responses. Results: Males reported significantly higher systolic (P \u3c 0.05) and diastolic (P \u3c 0.05) blood pressures than females as well as glucose levels (P \u3c 0.01). Males also reported higher amounts of work related stress (P \u3c 0.01). Conclusion: This preliminary investigation revealed that college age males reported significantly higher systolic and diastolic blood pressures as well as glucose levels than their female counterparts. Females had significantly higher HDL than males, but this is common in college age adults. There were no significant differences regarding stress components, cardiovascular or metabolic health outcomes and gender. Stress components such as work and finances were shown to correlate with systolic and diastolic blood pressure in both genders, but a larger sample size is needed to find a relationship. [j1

The association of mavenism and pleasure with food involvement in older adults

BACKGROUND: Food involvement is concerned with the involvement people have in the preparation and consumption of food. Little is known about older people’s food involvement or about the factors which may influence it. Therefore the main aim of this study was to examine food involvement and its associations among older Australians. METHODS: An Internet-based nationwide survey of 1,041 people aged 55 years and over (M = 66 years, SD 6.99) was conducted in 2012. Quota sampling was used to ensure that the age, gender and state of residence of the respondents were representative of the Australian population aged over 55 years. Bell and Marshall’s Food Involvement Scale was administered, along with questions pertaining to socio-demographic, social and hedonic factors. RESULTS: Overall predictor variables explained 45% (p = <0.0001) of variance in food involvement. Food mavenism and pleasure motivation for food were the factors most strongly associated with food involvement (β = .36; 95% CI .46, .61; p = < 0.0001 and β = .31; 95% CI .78, 1.08; p = < 0.0001, respectively). The predictive ability of demographic factors was reasonably poor. CONCLUSIONS: Food mavenism and pleasure motivation are stronger predictors of Food Involvement than demographic factors. This suggests communication and health promotion opportunities among older people

Information Security as Strategic (In)effectivity

Security of information flow is commonly understood as preventing any information leakage, regardless of how grave or harmless consequences the leakage can have. In this work, we suggest that information security is not a goal in itself, but rather a means of preventing potential attackers from compromising the correct behavior of the system. To formalize this, we first show how two information flows can be compared by looking at the adversary's ability to harm the system. Then, we propose that the information flow in a system is effectively information-secure if it does not allow for more harm than its idealized variant based on the classical notion of noninterference

ShopSmart 4 Health - protocol of a skills-based randomised controlled trial promoting fruit and vegetable consumption among socioeconomically disadvantaged women

BackgroundThere is a need for evidence on the most effective and cost-effective approaches for promoting healthy eating among groups that do not meet dietary recommendations for good health, such as those with low incomes or experiencing socioeconomic disadvantage. This paper describes the ShopSmart 4 Health study, a randomised controlled trial conducted by Deakin University, Coles Supermarkets and the Heart Foundation, to investigate the effectiveness and cost-effectiveness of a skill-building intervention for promoting increased purchasing and consumption of fruits and vegetables amongst women of low socioeconomic position (SEP).Methods/designShopSmart 4 Health employed a randomised controlled trial design. Women aged 18&ndash;60 years, holding a Coles store loyalty card, who shopped at Coles stores within socioeconomically disadvantaged neighbourhoods and met low-income eligibility criteria were invited to participate. Consenting women completed a baseline survey assessing food shopping and eating habits and food-related behaviours and attitudes. On receipt of their completed survey, women were randomised to either a skill-building intervention or a wait-list control condition. Intervention effects will be evaluated via self-completion surveys and using supermarket transaction sales data, collected at pre- and post-intervention and 6-month follow-up. An economic evaluation from a societal perspective using a cost-consequences approach will compare the costs and outcomes between intervention and control groups. Process evaluation will be undertaken to identify perceived value and effects of intervention components.DiscussionThis study will provide data to address the currently limited evidence base regarding the effectiveness and cost-effectiveness of skill-building intervention strategies aimed at increasing fruit and vegetable consumption among socioeconomically disadvantaged women, a target group at high risk of poor diets.<br /