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Background and Aims: The leaf economic spectrum (LES) is related to dry mass and nutrient investments towards photosynthetic processes and leaf structures, and to the duration of returns on those investments (leaf lifespan, LL). Phosphorus (P) is a key limiting nutrient for plant growth, yet it is unclear how the allocation of leaf P among different functions is coordinated with the LES. We addressed this question among 12 evergreen woody species co-occurring on P-impoverished soils in south-eastern Australia. Methods: Leaf 'economic' traits, including LL, leaf mass per area (LMA), light-saturated net photosynthetic rate per mass (Amass), dark respiration rate, P concentration ([Ptotal]), nitrogen concentration, and P resorption, were measured for three pioneer and nine non-pioneer species. Leaf P was separated into five functional fractions: orthophosphate P (Pi), metabolite P (PM), nucleic acid P (PN), lipid P (PL), and residual P (PR; phosphorylated proteins and unidentified compounds that contain P). Results: LL was negatively correlated with Amass and positively correlated with LMA, representing the LES. Pioneers occurred towards the short-LL end of the spectrum and exhibited higher [Ptotal] than non-pioneer species, primarily associated with higher concentrations of Pi, PN and PL. There were no significant correlations between leaf P fractions and LL or LMA, while Amass was positively correlated with the concentration of PR. Conclusions: Allocation of leaf P to different fractions varied substantially among species. This variation was partially associated with the LES, which may provide a mechanism underlying co-occurrence of species with different ecological strategies under P limitation. [ABSTRACT FROM AUTHOR]

Obesity and chronic disease are increasing problems in refugee populations. Afghani refugees undergoing hepatitis B vaccination between January 2015 and December 2017 at a general practice clinic received dietary counselling sessions in Dari by native speaking clinicians. Anthropometry, blood pressure, fasting lipids and liver function tests were measured at both visits with results compared over time. 110/119 refugees requiring hepatitis B vaccination were recruited into the study. Mean BMI was lower at follow up visits (25.4 vs 26.1 by wilcoxon signed rank test p 0.04) with 72 of 110 participants losing a median of 2 kg between visits (range 0.5–14 kg) a mean of 206 days after the initial consultation. Median triglyceride levels were lower at the second visit than the first (1.4 vs 1.3 mmol/L Wilcoxon signed rank test Z = 3.5, p 0.0004). This cohort of refugees lost weight and showed a small improvement in triglyceride levels between visits. [ABSTRACT FROM AUTHOR]

To understand how environmental conditions and reproductive events affect coral energetic status, seasonal variations in lipid and fatty acid profiles of the common scleractinian coral, Acropora millepora, were studied from pre-spawning in November 2009 until post-spawning in November 2010 at Halfway Island (in the Keppel Island Group, Southern Great Barrier Reef, Australia). Seasonal chlorophyll levels, photosynthetically active radiation (PAR), rainfall and water temperature were major drivers of the overall coral lipid profile, and this was particularly pronounced in correlations with the important, high-energy lipid, triacylglycerol. This likely reflected changing food sources and feeding modes (i.e. phototrophy vs heterotrophy), which corresponds to the opportunistic feeding behaviour of corals. Water temperature was also a major influencer of the coral fatty acid profile. In particular, saturated fatty acids correlated positively with water temperature, while polyunsaturated fatty acids correlated negatively, reflecting cell membrane fluidity regulation, which is necessary for coral to tolerate changing temperatures. Spawning and maternal provisioning also proved to be a major driver of change in the coral lipid profile. The mass spawning events in spring for both 2009 and 2010 caused reductions in the important coral egg constituents: wax ester, triacylglycerol, phosphatidylcholine and fatty acid 10:0. Interestingly, lipid accumulation was significantly lower in the 2010 spawn compared to 2009, possibly due to lower PAR and chlorophyll levels, reflecting reduced photosynthetic activity and phytoplankton availability. Regardless, in 2010, resource provisioning to egg production was greater than in 2009, suggesting increased reproductive effort in the face of environmental stress. This study demonstrates the strong influence of opportunistic heterotrophy and autotrophy and maternal provisioning on the coral lipid profile. Such information is fundamental to understanding the environmental and biochemical processes underlying coral health and predicting how anomalous events and climate-driven changes will affect coral reef assemblages. [ABSTRACT FROM AUTHOR]

Dyslipidaemia is a known risk factor for developing cardiovascular disease. The impact of ethnicity on variations in lipid patterns has been studied in certain racial and ethnic groups with limited data on other ethnicities, particularly Asian subgroups. This cross-sectional study evaluated the ethnic variation in lipid profile and its association with body composition and diet in ninety-one overweight and obese Australians of European (n = 32), Indian (n = 28) and Iranian (n = 31) ancestries. Different measures of total and truncal adiposity were assessed using the method of whole body dual energy X-ray absorptiometry. The results showed that serum total cholesterol (TC) and low density lipoprotein cholesterol (LDL-chol) levels in Iranians were significantly lower than in Europeans and Indians. Both Iranian and Indian groups exhibited lower mean high density lipoprotein cholesterol (HDL-chol) relative to Europeans. Triglycerides (TG) and HDL-chol, but not TC and LDL-chol, were significantly associated with different truncal adiposity measurements; however the degree of associations varied in ethnic groups. Regression analysis showed ethnicity as a significant predictor of TC ( p = 0.01), TG ( p = 0.03) and HDL-chol ( p = 0.04), after controlling for potential confounders. However, LDL-chol was significantly associated with the intake of total ( p = 0.005), and saturated fats ( p = 0.004), which were also other significant determinants of serum TC ( p = 0.04 and p = 0.02, respectively). In conclusion, ethnicity was a strong predictor of serum lipids, except LDL-chol which was significantly determined by dietary fat intake. Prevention and management of obesity, particularly abdominal adiposity may effectively reduce the risk of low HDL-chol reported in Iranians and Indians. [ABSTRACT FROM AUTHOR]

Background/objectives: Limited dietary intake tools have been validated specifically for hyperlipidaemic adults. The Australian Eating Survey (AES) Food Frequency Questionnaire (FFQ) was adapted to include foods with cardio-protective properties (CVD-AES). The aims were to estimate dietary fatty acid (FA) intakes derived from the CVD-AES and AES and compare them with red blood cell (RBC) membrane FA content.Subjects/methods: Dietary intake was measured using the semi-quantitative 120-item AES and 177-item CVD-AES. Nutrient intakes were calculated using AUSNUT 2011-2013. Fasting RBC membrane FAs were assessed using gas chromatography. Extent of agreement between intakes estimated by AES or CVD-AES and RBC membrane composition (% of total FAs) for linoleic acid (LA), alpha-linolenic acid (ALA), eicosapentanoic acid (EPA), docosapentaenoic acid (DPA) and docosahexaenoic acid (DHA) were assessed using Spearman's correlation coefficients, adjusted linear regressions and Kappa statistics.Results: Data from 39 participants (72% female, 59.3±11.1 years) indicate stronger positive correlations between RBC membrane FAs and CVD-AES dietary estimates compared with the AES. Significant (P<0.05) moderate-strong correlations were found between CVD-AES FAs and FA proportions in RBC membranes for EPA (r=0.62), DHA (r=0.53) and DPA (r=0.42), with a moderate correlation for LA (r=0.39) and no correlation with ALA. Significant moderate correlations were found with the AES for DHA (r=0.39), but not for LA, ALA, EPA or DPA.Conclusions: The CVD-AES provides a more accurate estimate of long chain FA intakes in hyperlipidaemic adults, compared with AES estimates. This indicates that a CVD-specific FFQ should be used when evaluating FA intakes in this population. [ABSTRACT FROM AUTHOR]