Compulsory work experience for chemistry majors – structure and successes

History Workplace Learning has been a compulsory component in the Analytical Chemistry major of the Bachelor of Science degree at Charles Sturt University (CSU) for over 20 years. Five years ago, this WIL experience was formalised into CHM335 Analytical Chemistry Industry Experience, a one semester subject with defined standards and assessments for the work being completed. The workplace learning component of the Analytical Chemistry major was formalised to meet the RACI requirements for accreditation and CSU requirements for WPL. In conversations among the Heads of Chemistry, it seems that while there are Chemistry some courses in Australia with optional work placement, this subject may be the first and only compulsory work placement subject for Chemistry majors. Structure CHM335 is a single semester subject that requires 5 weeks – a minimum of 180 hours - of chemical work in a commercial/industry/academic laboratory; these hours include 20 hours of laboratory induction and progress meetings with the employer/workplace supervisor; and the work conducted must be equivalent to 2nd/3rd year laboratory work. CHM335 is highly structured, with students required to identify and contact a workplace, prepare and submit a proposal requiring approval before starting the work placement, prepare 2 interim progress reports, a final assessment from the employer, and a final report from the student about the work completed, activities pursued, and skills developed. Successes Feedback from employers and students is overwhelmingly positive, with employers particularly impressed and satisfied with the formal structure and reporting required of the students. Employers report the CSU students have been inquisitive and committed. Perhaps the best success of the subject is students being offered a job at their CHM335 workplace upon completion of the subject. This talk will briefly discuss the Structure and Successes mentioned above, as well as address important questions associated with WPL subjects such as: How do we make sure students are ready to be sent to the workplace? How do you manage a number of students in various labs? How do we ensure the work completed by the students will be adequate? How do we assess the work completed by the students

Single and cumulative effects of whole-vine heat events on Shiraz berry composition

Aim: The aim of the study was to test the effect of a single heat event (HE), and the additive effects of repeated HEs at whole-vine level, on Shiraz berry composition, including detailed tannins. Methods and results: In a UV-transparent glasshouse, a system was developed to individually heat the above-ground parts of well-irrigated potted Shiraz vines without changing fruit and canopy light exposure. At the end of fruit set, and again prior to véraison, selected vines were heated to + 6 °C above ambient temperature for three consecutive days and nights in a combination of treatments to test the effect of a single HE and the additive effects of repeated HEs. A factorial design was used with four treatments (n=6): Control (C), heated at E-L 31 (HW1), heated at E-L 32 (HW2) and heated twice (HW1&2). Berries were sampled from fruit set until maturity at regular intervals, and primary and secondary metabolites, including detailed tannin composition, were analysed by GC-MS and LC-MS/MS, respectively. Temperatures (mean and maximum) inside the glasshouse were influenced by outside weather conditions and the 1st HE (HE1) was more intense than the 2nd (HE2). Photosynthesis was significantly decreased for the heated vines during HE1 where maximum temperature reached 45 °C, affecting both berry weight and titratable acidity (TA). HE2 was less intense with maximum temperature only reaching 40 °C, and had no effect on photosynthesis and less direct impact on composition. A few primary metabolites were affected by either HE1 or HE2 such as valine, leucine, pyruvic and lactic acids. Interactions between the two HEs were found for TA, malic acid and glucose at harvest. Skin tannin composition was significantly impacted by HE1, applied during the main biosynthesis period, but not by HE2. Epicatechin gallate terminal subunit concentration was the most impacted by heat. Seed physiology was also affected by HE1 and HE2 as well as seed tannin composition right after HE1. A small decrease in both total anthocyanins and total soluble solids at the end of véraison suggested that ripening was slightly delayed for HW1&2. Conclusions: Shiraz grapevines showed an elastic response to short heat stress between fruit set and véraison, with most impacts on physiology and composition observed during early post-treatment no longer evident by harvest. Significance and impact of the study: Increasing climate variability, with more frequent heatwaves, is a threat for viticulture in Australia where a large proportion of vineyards are located in already warm and hot regions. As grapevines may be exposed to abnormal high temperatures prior to véraison, knowledge on the effect of heat on metabolite biosynthesis occurring during this phase, such as tannins, is needed

Rasch analysis of exams: A way to document graduate outcomes to employers?

This presentation reports of a Rasch analysis (Rasch, 1960) performed on two final exams for first year, service taught, chemistry subjects. These subjects targeted students of vastly different educational backgrounds, but the exams were designed and proofed by the same team of academics. Using this approach, we were able to assess the performance of students as well as that of the exam questions (Bond and Fox, 2007). Importantly, we were pleased that for both exams, the performance of students correlated well with their grades. For each subject a number of important topics and categories of material exist as learning outcomes for the students. Analysis of the exam questions within these topics and categories allows a quantified measure of how each student does on each topic. This talk will briefly examine a sample of students’ information based upon these categories. It will suggest such information could be provided by students to employers in order to evidence the student’s mastery of a discipline, as defined in the subject(s) learning outcomes and along a scaffolded continuum (from first year to final year). Bond, T. G. and C. M. Fox (2007). Applying the Rasch Model. Fundamental Measurements in the Human Sciences. Mahwah, New Jersey, Routledge. Rasch, G. (1960). Probabilistic models for some intelligence and attainment tests. Copenhagen, Danmarks Paedagogiske Institut. Proceedings of the Australian Conference on Science and Mathematics Education, The University of Queensland, Sept 28th to 30th, 2016, page X, ISBN Number 978-0-9871834-4-6

Resumen ejecutivo del documento de consenso sobre el manejo de la patología renal en pacientes con infección por VIH

El objetivo de este documento es actualizar las recomendaciones sobre la evaluación y el manejo de la afectación renal en pacientes con infección por el VIH del año 2010. La función renal debe monitorizarse en todos los pacientes e incluir la medida de la concentración sérica de creatinina, la estimación del filtrado glomerular (ecuación CKD-EPI), la medida del cociente proteína/creatinina en orina y un sedimento urinario. El estudio básico de la función tubular ha de incluir la concentración sérica de fosfato y la tira reactiva de orina (glucosuria). En ausencia de alteraciones, el cribado será anual. En pacientes tratados con tenofovir o con factores de riesgo para el desarrollo de enfermedad renal crónica (ERC), se recomienda una evaluación más frecuente. Se debe evitar el uso de antirretrovirales potencialmente nefrotóxicos en pacientes con ERC o factores de riesgo para evitar su progresión. También se revisan las indicaciones de la biopsia renal, cuándo enviar el paciente al nefrólogo y las indicaciones, evaluación y manejo del paciente en diálisis o del trasplante renal

Formation of Pigment Precursor (+)-1 ''-Methylene-6 ''-hydroxy-2H-furan-5 ''-one-catechin Isomers from (+)-Catechin and a Degradation Product of Ascorbic Acid in a Model Wine System

The present study investigates the contribution of ascorbic acid to the formation of pigment precursors in model white wine systems containing (+)-catechin as the oxidizable phenolic substrate. The two main colorless products in these systems were structurally characterized as isomers of (+)-catechin substituted at either C6 or C8 on the A ring with a furan-type unit, namely, (+)-1 "-methylene-6"hydroxy-2H-furan-5"-one-6- catechin and (+)-1"-methylene-6"-hydroxy-2H-furan-5"-one-8- catechin. A known degradation product of ascorbic acid, L-xylosone, was separately prepared and, when reacted with (+)-catechin, generated the same (+)-furanone-catechin isomers as in model white wine systems. Incubation of these isomers in wine-like conditions yielded yellow xanthylium cation pigments. This study has shown that undesirable spoilage reactions (yellow coloration) can occur from a breakdown product of ascorbic acid-L-xylosone.8 page(s

Multi-Dimensional Antioxidant Screening of Selected Australian Native Plants and Putative Annotation of Active Compounds

Acacia implexa, Eucalyptus rossii and Exocarpos cupressiformis are native plants of Australia, which were used by the First Peoples for medicinal purposes. In this study, 70% aqueous ethanol crude extracts were prepared from A. implexa bark and leaves, E. rossii leaves and E. cupressiformis leaves, and partitioned via sequential extraction with n-hexane, dichloromethane (DCM), ethyl acetate and ethanol. The crude extracts and fractions were screened for antioxidant activity using a novel, high-throughput lipid-based antioxidant assay, as well as the aqueous ABTS (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) assay and the Folin–Ciocalteu test for total phenols. In the lipid-based assay, non-polar n-hexane and DCM fractions showed higher antioxidant activity against the formation of peroxides and thiobarbituric acid reactive substances (TBARS) than the other fractions, whereas the non-polar fractions were not effective in aqueous assays. This illustrates that the high potential of the lipid-soluble n-hexane and DCM fractions as antioxidants would have been missed if only aqueous-based assays were used. In addition, the potent antioxidant compounds were putatively annotated using liquid chromatography quadrupole time-of-flight mass spectrometry (LC-qTOF-MS). Gallic acid, (+)-catechin, (−)-epicatechin and tannins were found in most crude extracts

Correction: Ghani et al. Multi-Dimensional Antioxidant Screening of Selected Australian Native Plants and Putative Annotation of Active Compounds. <i>Molecules</i> 2023, <i>28</i>, 3106

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Impact of Fluorescent Lighting on Oxidation of Model Wine Solutions Containing Organic Acids and Iron

Previous studies have provided evidence that light exposure can increase oxygen consumption in wine and that the photodegradation of iron­(III) tartrate could contribute to this process. In the present study, model wine solutions containing iron­(III) and various organic acids, either alone or combined, were stored in sealed clear glass wine bottles and exposed to light from fluorescent lamps. Dissolved oxygen was monitored, and afterward the organic acid degradation products were determined and the capacity of the solutions to bind sulfur dioxide, the main wine preservative, was assessed. In the dark controls, little or no dissolved oxygen was consumed and the organic acids were stable. In the irradiated solutions, dissolved oxygen was consumed at a rate that was dependent on the specific organic acid present, and the latter were oxidized to various carbonyl compounds. For the solutions containing tartaric acid, malic acid, and/or citric acid, irradiation increased their sulfur dioxide-binding capacity