Lara Wakeling

The quantitative analysis of thiamin and riboflavin and their respective vitamers in fermented alcoholic beverages.

This research aimed to develop a simple and effective method for analyzing thiamin (B(1)), riboflavin (B(2)) and their respective vitamers by high performance liquid chromatography (HPLC) in fermented alcoholic beverages. The method developed here employs a phosphate buffer/methanol gradient elution on a single reverse phase column, coupled with independent fluorescent detection regimes. It also employs a precolumn derivatization to convert thiamin to thiochrome via an alkaline potassium ferricyanide solution. The method described here allowed a spike recovery of better than 97%, with a typical linear detection range (R(2) ≥ 0.9997) between ≤ 5 and ≥ 500 μg/L for all vitamers studied. Lager style beers were found to contain significantly (p < 0.001) less thiamin than other tested styles of beers (lager, 35.7 μg/L; ale, 88.3 μg/L; stout/porters, 104.4 μg/L; wheat beers, 130.7 μg/L), which may be due to the raw material and extensive processing that occurs for this style. There was no statistical difference (p = 0.608) between the riboflavin content of each beer style. Furthermore, wines and ciders contain less thiamin and riboflavin than beer, which is also likely to be due to the base materials used and the differences in processing steps to produce these beverages.

Approaches to study in undergraduate nursing students in regional Victoria, Australia.

Abstract In developmental research to devise a strategy to identify students who may benefit from assistance with learning habits, approaches to study were explored in undergraduate nursing students (n=122) enrolled in a compulsory first-year course in physiology at a regional Australian university. The course constituted 30 credits (25%) of their first year of study. Using the Approaches and Study Skills Inventory (ASSIST), students were identified as adopting a deep (n=38, 31%), strategic (n= 30, 25%), or a surface (n=54, 44%) approach to study. Internal consistency (Cronbach’s alpha [α]) for deep, strategic, and surface was 0.85, 0.87, and 0.76, respectively. Subsequently, a cluster analysis was done to identify two groupings: a “surface” group (n=53) and a “deep/strategic” group (n=69). The surface group scored lower in deep (33.28±6.42) and strategic (39.36±6.79) approaches and higher in the surface (46.96±9.57) approach. Conversely, the deep/strategic group scored 46.10±6.81, 57.17±7.81, and 41.87±6.47 in deep, strategic, and surface styles, respectively. This application of the ASSIST questionnaire and cluster analysis thus differentiated students adopting a surface approach to study. This strategy may enable educators to target resources, for example additional tutorial opportunities, peer-assisted study support, and tutor-led seminar sessions aimed at encouraging students to adopt a less superficial approach to study.

Effect of spatial distribution of wax and PEG-isocyanate on the morphology and hydrophobicity of starch films.

This study proposes a novel method for improving surface hydrophobicity of glycerol plasticized high amylose (HAG) films. We used polyethylene glycol isocyanate (PEG-iso) crosslinker to link HAG and three natural waxes (beeswax, candelilla wax and carnauba wax) to produce HAG+wax+PEG-iso films. The spatial distributions of wax and PEG-iso across the thickness of these films were determined using Synchrotron-based Fourier transform infrared spectroscopy. The hydrophobicity and surface morphology of the films were determined using contact angle (CA) and scanning electron microscopic measurements, respectively. The distribution patterns of wax and the PEG-iso across the thickness of the film, and the nature of crystalline patterns formed on the surface of these films were found to be the key factors affecting surface hydrophobicity. The highest hydrophobicity (CA >90°) was created when the PEG-iso was primarily distributed in the interior of the films and a hierarchical circular pinnacle structure of solidified wax was formed on the surface.