Crystalline polymorph transition in poly(vinylidene fluoride) (PVDF)/acrylic rubber(ACM)/clay partially miscible hybrid

This study investigates the intercalation of nanoclay in partially miscible blends of poly(vinylidene fluoride) (PVDF) and acrylic rubber(ACM). Transmission electron microscopy and X-ray diffraction technique were used to investigate the formation of nanoscale polymer blend/clay hybrids. Using Infrared spectroscopy and X-ray analysis, the different polymorph formation in PVDF nanocomposite and conjugated phases of partially miscible nanocomposite was studied. Nanoclay was found to induce β and γ polymorphs while ACM tend to induce α phase in this polymer system. It was shown that PVDF chains in ACM-rich phase of partially miscible nanocomposites interact with ACM chains which in return form α polymorph in the presence of ACM. Further observations revealed that nanoclay in α polymorph is wrapped by ACM molecules.

Decreasing dietary sodium while following a self-selected potassium-rich diet reduces blood pressure

Reducing dietary sodium reduces blood pressure (BP), a major risk factor for cardiovascular disease, but few studies have specifically examined the effect on BP of altering dietary sodium in the context of a high potassium diet. This randomized, crossover study compared BP values in volunteer subjects self-selecting food intake and consuming low levels of sodium (Na+; 50 mmol/d) with those consuming high levels of sodium (> or =20 mmol/d), in the context of a diet rich in potassium (K+). Sodium supplementation (NaSp) produced the difference in Na+ intake. Subjects (n = 108; 64 women, 44 men; 16 on antihypertensive therapy) had a mean age of 47.0 ± 10.1 y. Subjects were given dietary advice to achieve a low sodium (LS) diet with high potassium intake (50 mmol Na+/d, >80 mmol K+/d) and were allocated to NaSp (120 mmol Na+/d) or placebo treatment for 4 wk before crossover. The LS diet decreased urinary Na+ from baseline, 138.7 ± 5.3 mmol/d to 57.8 ± 3.8 mmol/d (P < 0.001). The NaSp treatment returned urinary Na+ to baseline levels 142.4 ± 3.7 mmol/d. Urinary K+ increased from baseline, 78.6 ± 2.3 to 86.6 ± 2.1 mmol/d with the LS diet and to 87.1 ± 2.1 mmol/d with NaSp treatment (P < 0.001). The LS diet reduced home systolic blood pressure (SBP) by 2.5 ± 0.8 mm Hg (P = 0.004), compared with the NaSp treatment. Hence, reducing Na+ intake from 140 to 60 mmol/d significantly decreased home SBP in subjects dwelling in a community setting who consumed a self-selected K+-rich diet, and this dietary modification could assist in lowering blood pressure in the general population.

Fat, rich and beautiful: changing socio-cultural paradigms associated with obesity risk, nutritional status and refugee children from sub-Saharan Africa

There has been an increase in Australia's intake of refugees and migrants from sub-Saharan Africa over the last two decades. These refugees have been exposed to nutritional risks prior to migration, which, together with changes associated with acculturation, impact on their health and nutritional status post-migration. However, there is a paucity of data in Australia that has examined the health and nutritional status of this ethnic minority in Australia. Despite basic research assessing the nutritional status of children, none have specifically concentrated on the health and nutritional situation of sub-Saharan refugee children. In the absence of such studies, this paper explores issues relating to obesity in sub-Saharan African refugee children within a cultural and public health framework. We begin by outlining the history of obesity and its cultural meaning. We then move to a consideration of predisposing factors for obesity and how these factors translate into obesity risk contexts of sub-Saharan refugees post-migration. We argue there are a number of key challenges related to culture and the relationship between socio-economic factors post-migration that require addressing by health professionals, dieticians and health educators to ensure the delivery of successful health outcomes.

Data rich digital architectural environments

The development of data rich digital environments for the construction industry has been problematic despite the initial optimism when their application to design and construction was first considered. This paper reviews the current state of the art research into the application of information technology in design and construction and identifies the more critical issues in its adoption. In conclusion the paper then proposes a preliminary theoretical model being developed as a research tool for investigation into highly detailed information flows in a case study building renovation project. This investigation aims to track the detailed information flows and knowledge system used by the stakeholders in the building project.

Process model to support data rich digital environments

This paper proposes a theoretical process model and the associated detailed information structure which reflects the complexity of information, stakeholder interaction and intellectual property concerns which are currently seen in the construction industry. This is being developed and tested against a field study renovation project. The field study project identifies information flows and interactions between stakeholders such as designers, project managers, clients, contractors, subcontractors and suppliers. The process model which is being established shows very high levels of complexity in dependencies and interdependencies between implicit and explicit information within the project design and construction teams. Without an understanding of these detailed and complex process interactions, proposals for the application of ICT to the construction industry will not reflect the requirements of those for whom they are being developed.

A stearic acid-rich diet improves thrombogenic and atherogenic risk factor profiles in healthy males

Objective: To determine whether healthy males who consumed increased amounts of dietary stearic acid compared with increased dietary palmitic acid exhibited any changes in their platelet aggregability, platelet fatty acid profiles, platelet morphology, or haemostatic factors.

Design: A randomized cross-over dietary intervention.

Subjects and interventions: Thirteen free-living healthy males consumed two experimental diets for 4 weeks with a 7 week washout between the two dietary periods. The diets consisted of ~30% of energy as fat (66% of which was the treatment fat) providing ~6.6% of energy as stearic acid (diet S) or ~7.8% of energy as palmitic acid (diet P). On days 0 and 28 of each dietary period, blood samples were collected and anthropometric and physiological measurements were recorded.

Results: Stearic acid was increased significantly in platelet phospholipids on diet S (by 22%), while on diet P palmitic acid levels in platelet phospholipids also increased significantly (8%). Mean platelet volume, coagulation factor FVII activity and plasma lipid concentrations were significantly decreased on diet S, while platelet aggregation was significantly increased on diet P.

Conclusion: Results from this study indicate that stearic acid (19 g/day) in the diet has beneficial effects on thrombogenic and atherogenic risk factors in males. The food industry might wish to consider the enrichment of foods with stearic acid in place of palmitic acid and trans fatty acids.

Effects of clay amendment on adsorption and desorption of copper in water repellent soils

Copper is an important micronutrient and trace amounts are essential for crop growth. However, high concentrations of copper will produce toxic effects. Australia is increasingly developing production of crops in water repellent soils. Clay amendment, a common amelioration techniques used in Australia, has demonstrated agronomic benefits in increased crop or pasture production. The sorption and desorption of copper and the effect of clay treatment on copper behaviour in a water repellent soil collected from an experimental farm in South Australia is studied. We found that the water repellent soils amended with clay have an increased adsorption capacity of copper. Also the clay-amended soils had an increased ratio of specific sorption to total sorption of copper. The implications of this study to the sustainable agro-environmental management of water repellent soils is discussed.

Exploring low-income women's welfare stigma through rich point analysis

The project described in this presentation was the final component of my PhD thesis which explored how Centrelink policies mediated social citizenship for low-income women. I first analysed the Centrelink Information Handbook, and then collected ethnographic data through observations and interviews. The first two of my research questions were quite deductive in nature, as I applied Levitas' (1998) conceptual framework of social exclusion to the Centrelink Information Handbook and low-income women's experiences. This third research question, to explore how low-income women's social citizenship was socially and politically mediated, however, required a more unstructured approach.

Water repellency, near-saturated infiltration and preferential solute transport in a macroporous clay soil

Little attention has been paid to the possibility that soil water repellency could enhance non-equilibrium water flow and solute transport through macropores present in structured clay soils. In this study, we measured infiltration and solute transport in a clay soil under near-saturated conditions in both the field using tension infiltrometers and in the laboratory on undisturbed soil columns. Measurements were made on adjacent plots under grass and continuous arable cultivation. Steady-state field infiltration rates measured using water and ethanol as the infiltrating fluids demonstrated that the soil macroporosity under grass was better developed, but that much of the structural pore system was inactive due to water repellency. No water repellency was detected on the arable plot disturbed by tillage. Dye tracing showed that the conducting macroporosity was largely comprised of earthworm channels in the grassed plot and inter-aggregate voids resulting from ploughing in the arable plot. Tracer breakthrough curves measured on field-dry soil indicated rapid macropore transport in columns taken from both plots, although the degree of non-equilibrium transport appeared somewhat stronger under grass. This result, which was attributed to water repellency, was also consistent with the larger flow-weighted mean pore size found in the field infiltration experiments. It is concluded that water repellency in undisturbed structured clay soils can have significant effects on the occurrence of non-equilibrium water and solute transport in macropores.