Associations between the home food environment and obesity-promoting eating behaviors in adolescence

Objective: This study examines relationships between multiple aspects of the home food environment and obesity-promoting characteristics of 12- to 13-year-old adolescents' diets, specifically frequency of consumption of high-energy fluids, sweet snacks, savory snacks, and take-out foods.

Research Methods: This was a cross-sectional study including 347 adolescents 12 to 13 years of age and their parents. Data were collected via self-completed surveys. The adolescents' diets were assessed using a Food Frequency Questionnaire derived from existing age-appropriate National Nutrition Survey data. An extensive range of domains within the home food environment were assessed. Bivariate linear regression analyses were run split by gender. Forced entry multiple linear regression analyses (adjusting for all variables significant in bivariate analyses as well as for maternal education) were also performed, stratified by the sex of the child.

Results: The influence of mothers, either as models for eating behaviors or as the providers of food, was pervasive. Mothers' intake of high-energy fluids (p = 0.003), sweet snacks (p = 0.010), savory snacks (p = 0.008), and take-out food (p = 0.007) was positively associated with boys' intake of all these foods. In addition, mothers' intake of high-energy fluids was positively associated with daughters' consumption of these drinks (p = 0.025). Furthermore, availability of unhealthy foods at home was positively associated with girls' sweet snack (p = 0.001), girls' savory snack (p < 0.001), boys' savory snack (p = 0.002), and, in the bivariate analyses, girls' high-energy fluid consumption (p = 0.002).

Discussion: This study of home food environment influences on adolescent diet highlights the pervasive influence of mothers in determining adolescents' obesity-promoting eating, providing direction for obesity prevention strategies and future research.

Cytokine receptor signaling through the Jak-Stat-Socs pathway in disease

The complexity of multicellular organisms is dependent on systems enabling cells to respond to specific stimuli. Cytokines and their receptors are one such system, whose perturbation can lead to a variety of disease states. This review represents an overview of our current understanding of the cytokine receptors, Janus kinases (Jaks), Signal transducers and activators of transcription (Stats) and Suppressors of cytokine signaling (Socs), focussing on their contribution to diseases of an immune or hematologic nature.

A sensitive procedure for the rapid determination of arsenic(III) by flow injection analysis and chemiluminescence detection

A novel chemiluminescence flow injection procedure for the determination of As(III) in aqueous samples is described. The method involves injection of As(III) samples into a 1% (m/v) sodium hexametaphosphate in 0.02 M H₂SO₄ carrier stream, which then merges at a Y-piece with a reagent stream consisting of potassium permanganate (5.0 × 10⁻⁵ M) made up in the acidic sodium hexametaphosphate carrier solution. The chemiluminescence intensity of the resulting reaction mixture was measured at a photomultiplier tube operated at a voltage of 0.93 kV. Under optimized conditions, the method is characterised by a linear range from 0.5 to 5.0 μg l⁻¹, a detection limit of 0.3 μg l⁻¹ and a sampling frequency of 150 h⁻¹. The effects of common anionic and cationic interferences were investigated, and it was found that the only ions to cause serious interference were those which react with potassium permanganate, namely sulphide, iodide and ferrous.

Short-term diets enriched in stearic or palmitic acids do not alter plasma lipids, platelet aggregation or platelet activation status

Objective: To determine whether healthy males who consumed increased amounts of dietary stearic acid compared with increased dietary palmitic acid through the consumption of commercially available foods, exhibited any changes in plasma lipids, platelet aggregation or platelet activation status.
Design: A randomised cross-over dietary intervention.
Subjects and interventions: Nine free-living healthy males consumed two experimental diets (stearic acid enriched, diet S, and palmitic acid enriched, diet P) for 3 weeks in a randomised cross-over design separated by a 3 week washout phase. The diets consisted of 30% of energy as fat (30% of which was derived from the treatment diets) providing 13 g=day as stearic acid and 17 g=day as palmitic acid on diet S and 7g=day as stearic acid and 22 g=day as palmitic acid on diet P. The dietary ratio of stearic to palmitic acids was 0.76 on diet S compared with 0.31 on diet P. Blood samples were collected on days 0 and 21 of each dietary period.
Results: LDL cholesterol levels and platelet aggregation response to the agonist ADP were significantly decreased (P <0.025) in subjects on diet S compared with day 0. Apart from that, there were no significant changes in plasma lipids, plateletaggregation, mean platelet volume and platelet reactivity between diets. There were no significant changes in stearic or palmitic acid levels in plasma phospholipid or triacylglycerol. There was a significant difference in palmitic acid levels in platelet phospholipids between the two diets.
Conclusions: Use of commonly available foods led to a 27% increase in stearic acid (diet S) and a 19% increase in palmitic acid (diet P), on diets S and P respectively, and no significant differences between the two diets in plasma lipoprotein concentrations, platelet aggregation or platelet activation status.

Annetocin and TCTP expressions in the earthworm Eisenia fetida exposed to PAHs in artificial soil

The toxicity of sublethal polycyclic aromatic hydrocarbons (PAHs) levels in soils was assessed by testing their impact on expression of annetocin, a reproduction regulating gene, and translationally controlled tumor protein (TCTP), a tumorigenic response gene, in the earthworm Eisenia fetida cultured in artificial soil spiked with, phenanthrene (Phe), pyrene (Pyr), fluoranthene (Flu), or benzo(a)pyrene (Bap). Annetocin and TCTP were both up-regulated by 0.1 and 1.0 mg kg−1 benzo(a)pyrene and TCTP was down-regulated by 10.0 mg kg−1 phenanthrene. Weight loss and cocoon production of the worms were also analyzed. Only 10.0 mg kg−1 phenanthrene impacted earthworm weight loss significantly and no significant differences on cocoon production were observed. Our study indicated that the potential ecotoxicity of sublethal PAHs in soil should not be neglected and mRNA transcription level in earthworms was a more sensitive indicator of PAHs exposure than traditional indexes using cocoon production as endpoints and/or using the whole-organism as the test materials.

Determinants of native avian richness in suburban remnant vegetation : implications for conservation planning

While urban areas are increasingly recognized as having potential value for biodiversity conservation, the relationship between biodiversity and the structure and configuration of the urban landscape is poorly understood. In this study we surveyed birds in 39 remnant patches of native vegetation of various sizes (range 1–107 ha) embedded in the suburban matrix in Melbourne, Australia. The total richness of species within remnants was strongly associated with the size of remnants. Remnant-reliant species displayed a much stronger response to remnant area than matrix-tolerant species indicating the importance of large remnants in maintaining representative bird assemblages. Large remnants are important for other ecological groups of species including migratory species, ground foraging birds and canopy foraging birds. Other landscape (e.g. amount of riparian vegetation) and structural components (e.g. shrub cover) of remnants have a lesser role in determining the richness of individual remnants. This research provides conservation managers and planners with a hierarchical process to reserve design and management in order to conserve the highest richness of native species within urban areas. First of all, conservation efforts should preferentially focus on the retention of larger remnants of native vegetation. Second, where possible, riparian vegetation should be included within reserves or, where it is already present, should be carefully managed to ensure its integrity. Third, efforts should be focused at maintaining appropriate habitat and vegetation structure and complexity.

Predictors of hysterectomy as a treatment for menstrual symptoms

Background: Hysterectomy is a common procedure in Australia; approximately 1 in 5 Australian women undergoing a hysterectomy by the age of 50 for indications such as fibroids, disorders of menstruation (including excessive or irregular menstrual bleeding), and endometriosis. However, little is known about the characteristics of women who have had the procedure or the predictors of hysterectomy as a treatment for menstrual problems. This study of 687 middle-aged Australian women suffering from menstrual symptoms aimed to identify the common health and demographic characteristics that were likely to lead to hysterectomy for the treatment of these problems.

Methods: A cross-sectional and a prospective cohort study were undertaken as a substudy of the Australian Longitudinal Study on Women's Health (Women's Health Australia). Women from the mid-aged cohort of the Women's Health Australia study who identified having menstrual problems (n = 715) in the 1996 and 1998 surveys or who had undergone a hysterectomy (n = 218) during that time were recruited. A self-administered instrument was mailed to the 933 women in 2000. Data were analyzed using backward logistic regression to identify the characteristics that increased the likelihood of women undergoing hysterectomy for the treatment of menstrual problems.

Results: Factors that increased the likelihood of hysterectomy as a treatment for menstrual problems were varied. They included the number of menstrual symptoms experienced (odds ratio [OR], 1.63; p < .005) or conditions diagnosed (such as fibroids or excessive menstrual bleeding; OR, 2.5; p < .0005), a perception that information was available about menstrual problems (OR, 1.16; p < .001), being influenced in the decision making process to elect a treatment option (OR, 1.25; p < .025), and dissatisfaction with the other treatments tried before hysterectomy (OR, 0.63; p < .0005).

Conclusions: Hysterectomy seem to be the treatment of choice for women experiencing a number of menstrual problems and less than satisfactory outcomes with other treatment options. Importantly, women appear to be making decisions based on the perception of sufficient information available about their menstrual problems, regardless of whether or not this was actually the case. Women are being influenced in their decision-making process to undergo a hysterectomy by health professionals, such as general practitioners and gynecologists.

Breaks in sedentary time

OBJECTIVE--Total sedentary (absence of whole-body movement) time is associated with obesity, abnormal glucose metabolism, and the metabolic syndrome. In addition to the effects of total sedentary time, the manner in which it is accumulated may also be important. We examined the association of breaks in objectively measured sedentary time with biological markers of metabolic risk.

RESEARCH DESIGN AND METHODS--Participants (n = 168, mean age 53.4 years) for this cross-sectional study were recruited from the 2004-2005 Australian Diabetes, Obesity and Lifestyle study. Sedentary time was measured by an accelerometer (counts/[minute^-1] < 100) worn during waking hours for seven consecutive days. Each interruption in sedentary time (counts/min [greater than or equal to] 100) was considered a break. Fasting plasma glucose, 2-h plasma glucose, serum triglycerides, HDL cholesterol, weight, height, waist circumference, and resting blood pressure were measured. MatLab was used to derive the breaks variable; SPSS was used for the statistical analysis.

RESULTS--Independent of total sedentary time and moderate-to-vigorous intensity activity time, increased breaks in sedentary time were beneficially associated with waist circumference (standardized ß = -0.16, 95% CI -0.31 to -0.02, P = 0.026), BMI (ß = -0.19, -0.35 to -0.02, P = 0.026), triglycerides (ß = -0.18, -0.34 to -0.02, P = 0.029), and 2-h plasma glucose (ß = -0.18, -0.34 to -0.02, P = 0.025).

CONCLUSIONS--This study provides evidence of the importance of avoiding prolonged uninterrupted periods of sedentary (primarily sitting) time. These findings suggest new public health recommendations regarding breaking up sedentary time that are complementary to those for physical activity.

Afternoon T : Testosterone level is higher in red than yellow male polychromatic lizards

Recent work on within-species polymorphism across a broad range of taxa has renewed and considerably increased the attention to this classic evolutionary area, notably in lizard species where colors covary with reproductive strategies. We demonstrate elsewhere that red-headed males beat yellow-headed males in staged contests for females in the Australian painted dragon lizard Ctenophorus pictus. This morph difference in behaviour is linked to what appears to be a convention of red dominance in male–male interactions set very early in ontogeny, long before coloration has developed. In the current note, we investigate the relationship between time of day, which is directly linked to vigilance time in territorial males, and plasma levels of testosterone and corticosterone. We show that red males have higher testosterone levels in late afternoon following a day of territory patrolling and a non-significant trend in plasma corticosterone levels that decline with time of day. In conclusion, there are significant differences in testosterone profile between the two color morphs, providing a potential proximate link to the behavioural differences between them.

Histological assessment of intermediate - and long-term creatine monohydrate supplementation in mice and rats

Creatine monohydrate (CrM) supplementation appears to be relatively safe based on data from short-term and intermediate-term human studies and results from several therapeutic trials. The purpose of the current study was to characterize pathological changes after intermediate-term and long-term CrM supplementation in mice [healthy control and SOD1 (G93A) transgenic] and rats (prednisolone and nonprednisolone treated). Histological assessment (18-20 organs/tissues) was performed on G93A mice after 159 days, and in Sprague-Dawley rats after 365 days, of CrM supplementation (2% wt/wt) compared with control feed. Liver histology was also evaluated in CD-1 mice after 300 days of low-dose CrM supplementation (0.025 and 0.05 g · kg^-1 · day^-1) and in Sprague-Dawley rats after 52 days of CrM supplementation (2% wt/wt) with and without prednisolone. Areas of hepatitis were observed in the livers of the CrM-supplemented G93A mice (P < 0.05), with no significant inflammatory lesions in any of the other 18-20 tissues/organs that were evaluated. The CD-1 mice also showed significant hepatic inflammatory lesions (P < 0.05), yet there was no negative effect of CrM on liver histology in the Sprague-Dawley rats after intermediate-term or long-term supplementation nor was inflammation seen in any other tissues/organs (P = not significant). Dietary CrM supplementation can induce inflammatory changes in the liver of mice, but not rats. The observed inflammatory changes in the murine liver must be considered in the evaluation of hepatic metabolism in CrM-supplemented mice. Species differences must be considered in the evaluation of toxicological and physiological studies.

An evaluation of the performance of advanced melded composite joints

Melding is an efficient three step composite joining process that involves the selective cure of composite adherends before the final adhesive joint is created using the adherends own resin system. Melding does not require many of the processes and compromises associated with conventional techniques like adhesive bonding and mechanical fastening.

The Taguchi design of experiments technique was used to optimise three melded joint factors for a unidirectional epoxy prepreg material. The performance of the joint was evaluated using tensile and flexural strength as well as flexural modulus. It was found that not having a step for every ply in the joint was the most influential factor affecting joint performance. This was due to the differing failure modes induced by this factors various levels, which varied the amount of fibre breakage at failure.

Surface patterns induced by laser irradiation on thin polymer bilayer films

We report on the preparation of wavelike surface patterns with characteristic wavelengths on thin bilayers of poly(methyl methacrylate) on azobenzene liquid crystalline polymer films (LCP/PMMA) by irradiation of a single polarized pulsed laser beam. The formation of such patterns was influenced by the thickness of the upper layer and the laser fluence. We were also able to guide the wavelike pattern to have a specific orientation by placing an elastic polydimethylsiloxane (PDMS) mold on the surface of bilayer film prior to laser irradiation. Moreover, the property of the laser irradiation, that is, the selectivity through mask-projection systems, allowed us fabricating complicated micropattems for novel microdevices. (c) 2007 Elsevier B.V. All rights reserved.

Waist circumference has heterogeneous impact on development of diabetes in different populations : Longitudinal comparative study between Australia and Iran

Aims : Comparing waist circumference (WC) role in diabetes risk prediction and diagnosis of metabolic syndrome (MS) in different populations.

Methods : Population-based samples from Australia (n = 9026) and Iran (n = 8259) were studied in 2000 and followed for 4 years. Follow-up attendance was 58% and mean age was 51 vs. 47. Pearson correlations calculated between WC and other MS components. ROC for the role of WC in the prediction of incident diabetes was used.

Results : Prevalences of MS (48% vs. 28%), an increased WC (58.5% vs. 54.5%), low HDL-C (35% vs. 11.2%), high triglyceride (52.2% vs. 29.6%) were significantly higher in Iran. Fasting glucose ≥5.6 mmol/L was higher in Australia (26% vs. 23%). Hypertension was no different (38%). Pearson correlations between WC and other MS components were stronger in Australians: FPG (0.32 vs. 0.2), HDL (0.47 vs. 0.16), TG (0.38 vs. 0.30) and SBP (0.38 vs. 0.36). Among women, area under ROC curve for WC as a predictor for diabetes was significantly higher for Australians (0.76 vs. 0.68, p < 0.001) with no difference among men (0.69 vs. 0.71, p = 0.4).

Conclusion : WC was more strongly related to other components of MS in Australia. Association between WC and MS or incident diabetes varies between ethnicities.

Solar thermal aided power generation

Fossil fuel based power generation is and will still be the back bone of our world economy, albeit such form of power generation significantly contributes to global CO2 emissions. Solar energy is a clean, environmental friendly energy source for power generation, however solar photovoltaic electricity generation is not practical for large commercial scales due to its cost and high-tech nature. Solar thermal is another way to use solar energy to generate power. Many attempts to establish solar (solo) thermal power stations have been practiced all over the world. Although there are some advantages in solo solar thermal power systems, the efficiencies and costs of these systems are not so attractive. Alternately by modifying, if possible, the existing coal-fired power stations to generate green sustainable power, a much more efficient means of power generation can be reached. This paper presents the concept of solar aided power generation in conventional coal-fired power stations, i.e., integrating solar (thermal) energy into conventional fossil fuelled power generation cycles (termed as solar aided thermal power). The solar aided power generation (SAPG) concept has technically been derived to use the strong points of the two technologies (traditional regenerative Rankine cycle with relatively higher efficiency and solar heating at relatively low temperature range). The SAPG does not only contribute to increase the efficiencies of the conventional power station and reduce its emission of the greenhouse gases, but also provides a better way to use solar heat to generate the power. This paper presents the advantages of the SAPG at conceptual level.