Human exposure to particulate and gaseous pollutants in a bar.

There is increasing evidence of a causal link between airborne particles and ill health and this study examined the exposure to both airborne particles and the gas phase contaminants of environmental tobacco smoke (ETS) in a bar. The work reported here utilized concurrent and continuous monitoring using real-time optical scattering personal samplers to record particulate (PM10) concentrations at two internal locations. Very high episodes were observed in seating areas compared with the bar area. A photo-acoustic multi-gas analyser was used to record the gas phases (CO and CO2) at eight different locations throughout the bar and showed little spatial variation. This gave a clear indication of the problems associated with achieving acceptable Indoor Air Quality in a public space and identified a fundamental problem with the simplistic design approach taken to ventilate the space. Both gaseous and particulate concentrations within the bar were below maximum recommended levels although the time-series analysis illustrated the highly episodic nature of this exposure.

Public feedback - but personal feedforward?

Academic feedback is taken here as the reporting to student writers of the strengths and weaknesses of their submitted draft work, while academic feedforward refers to constructive advice regarding possible strengthening of students’ next work. Both originate from a tutor’s initial judgement of a student’s work. Feedback and feedforward on work showing need for improvement are problematic in a Confucian Heritage Culture. Even gently constructive advice within a programme seeking evidence for assessment of critical thinking may lead to perception of hurtful criticism by Taiwanese students. Some could withdraw from class activity accordingly. So the writers adjusted their response style. They now choose between different approaches featuring tutorial feedback or feedforward, depending on the standard of work being judged. When individual postings feature poor critical thinking, the writers opt for private messages concentrating on constructive feedforward. For better postings, they provide positive feedback with reasons for their judgements, and summarise to the class these exemplars of generic strengths in critical thinking. They also offer private prompting when they see scope for further enrichment of an able student’s critical thinking. This might also be a useful practice when tutoring solely in the West. (192 words) Keywords: Confucian Heritage Culture, public feedback, private feedforward, assessment

The total margin of exposure of ethanol and acetaldehyde for heavy drinkers consuming cider or vodka

Heavy drinkers in Scotland may consume 1600 g ethanol per week. Due to its low price, cider may be preferred over other beverages. Anecdotal evidence has linked cider to specific health hazards beyond other alcoholic beverages. To examine this hypothesis, nine apple and pear cider samples were chemically analysed for constituents and contaminants. None of the products exceeded regulatory or toxicological thresholds, but the regular occurrence of acetaldehyde in cider was detected. To provide a quantitative risk assessment, two collectives of exclusive drinkers of cider and vodka were compared and the intake of acetaldehyde was estimated using probabilistic MonteeCarlo type analysis. The cider consumers were found to ingest more than 200-times the amount of acetaldehyde consumed by vodka consumers. The margins of exposure (MOE) of acetaldehyde were 224 for the cider and over 220,000 for vodka consumers. However, if the effects of ethanol were considered in a cumulative assessment of the combined MOE, the effect of acetaldehyde was minor and the combined MOE for both groups was 0.3. We suggest that alcohol policy priority should be given on reducing ethanol intake by measures such as minimum pricing, rather than to focus on acetaldehyde.