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Reasoning about visual representations in science requires the ability to control one's attention, inhibit attention to irrelevant or incorrect information, and hold information in mind while manipulating it actively--all aspects of the limited-capacity cognitive system described as humans' executive functions. This article describes pedagogical intuitions on best practices for how to sequence visual representations among pre-service teachers, adult undergraduates, and middle school children, with learning also tested in the middle school sample. Interestingly, at all ages, most people reported beliefs about teaching others that were different from beliefs about how they would learn. Teaching beliefs were most often that others would learn better from presenting representations one at a time, serially; while learning beliefs were that they themselves would learn best from simultaneous presentations. Students did learn best from simultaneously presented representations of mitosis and meiosis, but only when paired with self-explanation prompts to discuss the relationships between the graphics. These results provide new recommendations for helping students draw connections across visual representations, particularly mitosis and meiosis, and suggest that science educators would benefit from shifting their teaching beliefs to align with beliefs about their own learning from multiple visual representations.

Follow-up has continued on the cohort of miners and millers of crocidolite from Wittenoom Gorge in Western Australia. Previous analyses had indicated that the incidence of mesothelioma continued to rise exponentially past 40 yr after first exposure, but that fibres were cleared from the lungs with a half-life of ~7 yr. Success in follow-up has been improved through searches in Italy and in the Australian National Death Index. While the mesothelioma rate is still high, the incidence of the disease appears to have levelled out in this cohort. [ABSTRACT FROM AUTHOR]

Objectives: To estimate the relations between exposure to both tobacco smoke and crocidolite and the incidence of various histological types of lung cancer.Methods: In 1979 all former workers from the Wittenoom asbestos industry who could be traced were sent a questionnaire on smoking history. Of 2928 questionnaires sent, satisfactory replies were received from 2400 men and 149 women. Of the men, 80% had smoked at some time and 50% still smoked. Occupational exposure to crocidolite was known from employment records and follow up was maintained through death and cancer registries in Australia with histological diagnoses obtained from the relevant State Cancer Registry. Conditional logistic regression was used to estimate the effects of tobacco and asbestos exposure on incidence of different cell types of lung cancer in a nested case-control design.Results: Between 1979 and 1990, 71 cases of lung cancer occurred among men in this cohort: 27% squamous cell carcinoma, 31% adenocarcinoma, 18% small cell carcinoma, 11% large cell carcinoma, and 13% unclassified or indeterminate. Two of the classified cases and one unclassified case had never smoked. The incidence of both squamous and adenocarcinoma types of lung cancer were greatest in ex-smokers and in those subjects with the highest levels of exposure to crocidolite. After adjustment for smoking habit, the increase in incidence of lung cancer with increasing exposure to crocidolite was greater for squamous cell carcinoma than for adenocarcinoma.Conclusions: The results from this study have shown significant exposure-response effects for exposure to crocidolite, and both adenocarcinoma and squamous cell carcinoma of the lung. They also provide some further evidence against the theory that parenchymal fibrosis induced by asbestos is a necessary precursor to asbestos induced lung cancer. [ABSTRACT FROM AUTHOR]

The objective of this article is to assign individual airborne crocidolite exposure levels to former residents of the town of Wittenoom, Western Australia. All environmental monitoring programs carried out in the town since 1966 were reviewed and assessed for their suitability for use in estimating individual exposure to crocidolite. These programs measured respirable fibers greater than 5 mu m in length. Duration of residence was determined from questionnaires, work history sheets of the Australian Blue Asbestos Company, and the various sourcesused to assemble a cohort of previous residents. All exposure measurements were calculated assuming continuous exposure over 24 hours perday, 7 days per week. Intensity of exposure and cumulative exposure were estimated for each person in the cohort. All environmental monitoring surveys carried out at Wittenoom have detected some crocidolitefibers. The levels of fibers have shown a continuing decrease since the mining operations ceased in 1966. Most of the cohort stayed at Wittenoom longer than 1 year and had a median estimated intensity of exposure of 0.5 fibers per milliliter and a median estimated cumulativeexposure of 2.8 fiber-years per milliliter. As a result of the crocidolite mining operations at Wittenoom, the residents of the town, even as late as 1992, have been continuously exposed to higher levels ofairborne crocidolite than other populations where no such source of contamination exists. [ABSTRACT FROM AUTHOR]

Twin registers have been established worldwide to study the roles of genes and the environment in health and behaviour. While questionnaire surveys are thought to be the most cost-effective way of collecting large amounts of data, low response rates can result in response bias. Many different strategies have been proposed to maximise response rates. A register of all multiple births occurring in Western Australia (WA) from 1980 onwards has been established using probabilistic record linkage techniques. Families who had not experienced the death of one or more of their multiples were invited to participate in the Western Australian Twin Child Health (WATCH) study, which studied the genetic and environmental determinants of childhood asthma and atopy. Several questionnaire designs and follow-up methods were assessed. We have shown that it was feasible to use a population-based register of multiple births to contact families for a questionnaire study. Questionnaire length, mode of follow-up, the number of responses required and the of participants all seemed to affect response.

This paper describes the creation of a unique maternal identifier for use in the investigation of perinatal, postneonatal and child outcomes in relation to maternal characteristics. All Midwives' records of Western Australian (WA) births were routinely linked to registrations of births and deaths for infants born from 1980 to 1992 inclusive, then linked to WA hospital discharge data and to registries of birth defects and cerebral palsy to create a longitudinal health record for each infant. However, since each birth to a woman was recorded as a separate event, there was no way to identify siblings. Probabilistic record linkage, based on information about the mother, was used for this task. Logical inconsistencies within the data were used to test the validity of the linkages between birth records attributed to each mother. Information about the mother from other epidemiological studies and data abstracted from hospital case notes was also used to validate sibships. Linkage of the records of 310,255 births in WA during that period resulted in the formation of 181,133 sibships of one or more children. Pooling the results of all of the validation methods gave an error of 0.9%. Linkage identified 3678 sibships containing multiple births, and 305 sets of maternal twins. Ascertainment of twins and their siblings for an ongoing twin register, the WA Twin Child Health (WATCH) study, was a natural consequence of this process.