Distribution and density of the hooded plover Thinornis rubricollis along a remote coastline in North West Tasmania

The Arthur-Pieman Conservation Area, on the north-west coast of Tasmania, provides many kilometres of ocean beach habitat for the vulnerable Hooded Plover Thinornis rubricollis. Hooded Plovers were surveyed along a 43.5 km section of coast which included both rocky shores and sandy beaches. They were absent from the rocky portion of the coastline (17.0 km), but 65 individuals were recorded along the sandy portion of coastline (26.5 km). The recorded population density of 2.45 birds/km compares favourably with reported mean densities for most parts of south-eastern Australia. Careful management and monitoring are required if the current numbers of the Hooded Plover in this area are to be maintained.

Energy density of foods and beverages in the Australian food supply: influence of macronutrients and comparison to dietary intake

Objectives: The energy density (ED) of the diet is considered an important determinant of total energy intake and thus energy balance and weight change. We aimed to compare relationships between ED and macronutrient content in individual food and beverage items as well as population diet in a typical Western country. Design: Nutrient data for 3673 food items and 247 beverage items came from the Australian Food and Nutrient database (AusNut). Food and beverage intake data came from the 1995 Australian National Nutrition Survey (a 24-h dietary recall survey in 13 858 people over the age of 2). Relationships between ED and macronutrient and water content were analysed by linear regression with 95% prediction bands. Results: For both individual food items and population food intake, there was a positive relationship between ED and percent energy as fat and negative relationships between ED and percent energy as carbohydrate and percent water by weight. In all cases, there was close agreement between the slopes of the regression lines between food items and dietary intake. There were no clear relationships between ED and macronutrient content for beverage items. Carbohydrate (mostly sucrose) contributed 91, 47, and 25% of total energy for sugar-based, fat-based, and alcohol-based beverages respectively. Conclusions: The relationship between ED and fat content of foods holds true across both population diets and individual food items available in the food supply in a typical Western country such as Australia. As high-fat diets are associated with a high BMI, population measures with an overall aim of reducing the ED of diets may be effective in mediating the growing problem of overweight and obesity.

Chemical composition and tissue energy density of the cuttlefish (Sepia apama) and its assimilation efficiency by Diomedea albatrosses.

The cuttlefish Sepia apama Gray (Mollusca: Cephalopoda) is a seasonally abundant food resource exploited annually by moulting albatrosses throughout winter and early spring in the coastal waters of New South Wales, Australia. To assess its nutritional value as albatross forage, we analysed S. apama for water, lipid protein, ash contents, energy density and amino acid composition. Because albatrosses consistently consume S. apama parts preferentially in the order of head, viscera and mantle, we analysed these sections separately, but did not identify any nutritional basis for this selective feeding behaviour. The gross energy value of S. apama bodies was 20.9 kJ/g dry mass, but their high water content (>83%; cf <70% for fish) results in a relatively low energy density of 3.53 kJ/g. This may contribute to a need to take large meals, which subsequently degrade flight performance. Protein content was typically >75% dry mass, whereas fat content was only about 1%. Albatrosses feed on many species of cephalopods and teleost fish, and we found the amino acid composition of S. apama to be comparable to a range of species within these taxa. We used S. apama exclusively in feeding trials to estimate the energy assimilation efficiency for Diomedea albatrosses. We estimated their nitrogen-corrected apparent energy assimilation efficiency for consuming this prey to be 81.82 ± 0.72% and nitrogen retention as 2.90 ± 0.11 g N kg^-1 d^-1. Although S. apama has a high water content and relatively low energy density, its protein composition is otherwise comparable to other albatross prey species. Consequently, the large size and seasonal abundance of this prey should ensure that albatrosses remain replete and adequately nourished on this forage while undergoing moult.

Reducing the energy density of multiple meals decreases the energy intake of preschool-age children1,2,3

Background: The energy density (ED) of an entrée affects children's energy intake at a meal consumed ad libitum. However, the effects in children of changing the ED of meals over multiple days are unknown.

Objective: We aimed to test the effect of reducing the ED of multiple meals on the ad libitum energy intake of preschool-age children over 2 d.

Design: In this crossover study, 3- to 5-y-old children (n = 10 boys, 16 girls) were served manipulated breakfasts, lunches, and afternoon snacks 2 d/wk for 2 wk. Foods and beverages served at these meals during 1 wk were lower in ED than were those served during the other week. ED reductions were achieved by decreasing fat and sugar and by increasing fruit and vegetables. Dinner and an evening snack were sent home with children, but these meals did not vary in ED. The same 2-d menu was served in both conditions.

Results: Children consumed a consistent weight of foods and beverages over 2 d in both conditions, and therefore their energy consumption declined by 389 ± 72 kcal (14%) in the lower-ED condition, a significant decrease (P < 0.0001). Differences in energy intake were significant at breakfast on day 1, and they accumulated at manipulated meals over 2 d (P < 0.01). Intake of the nonmanipulated meals was similar between conditions.

Conclusions: Children's energy intake is influenced by the ED of foods and beverages served over multiple days. These results strengthen the evidence that reducing the ED of the diet is an effective strategy for moderating children's energy intake.

Reducing the energy density of an entrée decreases children’s energy intake at lunch

Background: Strategies need to be developed to reduce preschool children’s energy intake.

Objective: To test the effect of reducing the energy density of an entrée on children’s ad libitum energy intake.

Subjects: Subjects were 2- to 5-year-old children (37 boys and 40 girls) in a university day-care facility.

Intervention: In this within-subjects crossover study, children were served a test lunch once per week for 6 weeks. Two versions of a macaroni and cheese entrée were formulated to differ in energy density while maintaining similar palatability. Each version was served to children three times. The higher-energy-density entrée had 2.0 kcal/g and the other entrée was 30% lower in energy density. Lunch, consumed ad libitum, also included broccoli, applesauce, and milk.

Main outcome measures: Food intake and energy intake were measured.

Statistical analyses: A mixed linear model tested effect of energy density of the entrée on food intake and energy intake. Results are reported as mean±standard error.

Results: Decreasing the energy density of the entrée by 30% significantly (P<0.0001) reduced children’s energy intake from the entrée by 25% (72.3±8.3 kcal) and total lunch energy intake by 18% (71.8±7.9 kcal). Children consumed significantly more of the lower-energy-density entrée (10.1±4.2 g; P<0.05). Children’s sex-specific body mass index–for-age percentiles did not affect the relationship between energy density of the entrée and children’s intakes.

Conclusions: Decreasing the energy density of a lunch entrée resulted in a reduction in children’s energy intake from the entrée and from the total meal. Reducing the energy density of foods may be an effective strategy to moderate children’s energy intake.

Simulation of a device concept for noninvasive sensing of blood glucose levels

This paper introduces a method of modeling noninvasive glucose sensing for patients who suffer from diabetes mellitus. The proposed technique involves simulation of light propagation through biological tissue with an embedded photonic crystal. The proposed detection technique is Raman spectroscopy and the use of the photonic crystal enables the enhancement of Raman scattering by engineering the photon density of states. Further enhancement can be achieved using noble metal clusters which result in surface enhanced Raman scattering and has the ability to provide enhancements of up to a million times.

Misconceptions about density of decimals : insights from Indonesian pre-service teachers’ work

Extensive studies have documented various difficulties with, and misconceptions about, decimal numeration across different levels of education. This paper reports on pre-service teachers’ misconceptions about the density of decimals. Written test data from 140 Indonesian pre-service teachers, observation of group and classroom discussions provided evidence of pre-service teachers’ difficulties in grasping the density notion of decimals. This research was situated in a teacher education university in Yogyakarta, Indonesia. Incorrect analogies resulting from over generalization of knowledge about whole numbers and fractions were identified. Teaching ideas to resolve these difficulties and challenges in resolving pre-service teachers’ misconceptions are discussed. Evidence from this research indicates that it is possible to remove misconceptions about density of decimals.

The relationship between the density of alcohol outlets and parental supply of alcohol to adolescents

This study investigated whether the number of alcohol outlets per 10,000 population in a given area (density) influenced parental supply of alcohol to adolescents; differences in Australian born and acculturating parents were also examined. A state-representative student survey in Victoria identified that the majority of adolescents (55%) reported that they had used alcohol in the past 12 months; 34 % of those who had consumed alcohol reported that it had been supplied by their parents. Multilevel modelling identified that there were no overall effects of density, however there were different effects based on parent country of birth and type of license. Specifically, each unit increase in the density of takeaway liquor stores increased the likelihood by 2.03 that children with both Australian-born parents would be supplied alcohol. Adolescents with both migrant parents on the other hand, had a 1.36 increased risk of being supplied alcohol as the density of outlets requiring at-venue consumption increased. The findings of this study suggest that in Australia, alcohol outlet density is associated with parental supply of alcohol to children, with this effect moderated by the cultural background of the parent and type of outlet density. Future research should investigate the association between the density of alcohol outlets and public approval of parents supplying alcohol to adolescents.

Facile preparation and thermoelectric properties of Bi₂Te₃ based alloy nanosheet/PEDOT:PSS composite films

Bi2Te3 based alloy nanosheet (NS)/poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) composite films were prepared separately by spin coating and drop casting techniques. The drop cast composite film containing 4.10 wt % Bi2Te3 based alloy NSs showed electrical conductivity as high as 1295.21 S/cm, which is higher than that (753.8 S/cm) of a dimethyl sulfoxide doped PEDOT:PSS film prepared under the same condition and that (850-1250 S/cm) of the Bi2Te3 based alloy bulk material. The composite film also showed a very high power factor value, ∼32.26 μWm(-1) K(-2). With the content of Bi2Te3 based alloy NSs increasing from 0 to 4.10 wt %, the electrical conductivity and Seebeck coefficient of the composite films increase simultaneously.

The influence on population weight gain and obesity of the macronutrient composition and energy density of the food supply

Rates of overweight and obesity have increased dramatically in all regions of the world over the last few decades. Almost all of the world's population now has ubiquitous access to low-cost, but highly-processed, energy-dense, nutrient-poor food products. These changes in the food supply, rather than decreases in physical activity, are most likely the primary driver of population weight gain and obesity. To-date, the majority of prevention efforts focus on personalised approaches targeting individuals. Population-wide food supply interventions addressing sodium and trans fat reduction have proven highly effective and comparable efforts are now required to target obesity. The evidence suggests that strategies focusing upon reducing the energy density and portion size of foods will be more effective than those targeting specific macronutrients. Government leadership, clearly specified targets, accountability and transparency will be the key to achieving the food supply changes required to address the global obesity epidemic.

The density of alcohol outlets and adolescent alcohol consumption: an Australian longitudinal analysis

 Higher density of alcohol outlets has been linked to increased levels of adolescent alcohol-related behaviour. Research to date has been cross-sectional. A longitudinal design using two waves of annual survey data from the Australian arm of the International Youth Development Study was used. The sample comprised 2835 individuals with average age at wave 2 of 14 years (SD=1.67; range=11–17 years). GSEM was used to examine how absolute levels of alcohol outlet density was associated with student-reported alcohol use one year later, while controlling for prior alcohol use, risk factors at wave one and changes in density over the 2 years. Adolescents' perception of alcohol availability and friends' alcohol use were tested as potential mediators of the association between alcohol outlet density and adolescent alcohol use. Elasticity modelling identified a 10% increase in overall density at wave one was associated with an approximately 17% increase in odds of adolescent alcohol consumption at wave two. Living in areas with a higher density of outlets was associated with a statistically significant increase in the likelihood of adolescents developing early age alcohol consumption.