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In this day and age, it seems that genes are "everything" when it comes to determining the characteristics of an organism. However, the importance of the environment in biology cannot be denied. For example, nearly everyone knows that a dry season can ruin crop yields. However, digging a little deeper reveals even more intriguing examples of environmental influence on organisms. For instance, research has shown that the sex of some species of reptiles is influenced by the temperature at which the reptiles' eggs are incubated during development. This kind of observation presents an apparent paradox, because sex is usually regarded as being genetically—not environmentally—determined. 

Thus, there appear to be certain situations in which the environment affects not only the growth and health of an organism, but also the use or deployment of the organism's genes. Does this mean that genes aren't, in fact, everything? The observation that genetically identical organisms often vary greatly in phenotype clearly shows that gene-environment interaction is indeed an important regulator of phenotypic variation, including variation related to a number of diseases. In fact, the impact of environmental factors on disease etiology (or causation) has gained greater recognition in recent years. This has led to the conclusion that both genes and environment can affect disease—not just separately, but through direct interaction with each other. This relatively new attitude presents considerable challenges, as well as surprising benefits, for the study of human disease.

The number of combinations of different genotypic variants, environmental conditions, and possible phenotypes is not something researchers can predict. However, the complex interactions of multiple genetic loci with diverse environmental signals suggest that scientists must continue to develop novel methods of studying these situations, such as by simultaneously examining thousands of genes using techniques like microarray technology under different environmental conditions. While we may never be able to predict an exact phenotype, it is clear that when trying to understand biology and human disease, we must consider interactions of genes and environment in our analysis.

Unlike many other countries, physics is highly popular in secondary education in Scotland, with large numbers opting for study at the Higher Grade on which entry to higher education is based. This paper reports a project that explored the attitudes and perceptions of Scottish girls and boys towards physics over the age range of 10-18 years old. Towards the end of primary school, attitudes towards science are very positive and both boys and girls are looking forward to studying more science in secondary school, althoughthere is no evidence that the introduction of primary science has been a factor. By the end of the second year of secondary school, these positive attitudes have declined quite markedly and a significant decline of girls' attitudes towards science relative to boys' attitudes was clearly observed. The success of the Standard Grade physics course (a 2-year course taken in third and fourth year, ages 14-16 approximately) is easy to observe in terms of the restoration of positive attitudes of boys and girls again as the pupils move through third and fourth year. This process is especially clearly marked among girls. Surprisingly, over 90 per cent of the observed fourth year pupils wanted to continue studies in physics but a marked decline in attitude is observed during the Higher Grade course (a 1-year course which follows Standard Grade), this being more marked for boys. If the number of girls in physics is an issue for concern within the structure of Scottish system, then the focus of attention should be the structure and nature of the science course in the early secondary school.

Gender gaps in physics in favour of boys are more prominent in Israel than in other countries. The main research question is to find out what gender issues are at play in Israeli advanced placement physics classes. Matriculation exam scores from approximately 400 high schools were analysed across 12 years. In addition, semi-constructed interviews were conducted with 50 advanced placement physics students (25 girls and 25 boys). In terms of participation, it was found that the ratio of girls to boys has been unchanged from 1988 to 2000 and is roughly 1:3. In terms of performance, it was found that the final matriculation scores of boys and girls are similar. However, breaking up the final scores into its two components - teachers' given grades and matriculation test scores - showed that boy's test scores are usually higher than girls' test scores, while girls' teachers' given grades are usually higher than boys'. Results from semi-constructed interviews pointed to two factors that are especially unfavourable to many girls: excessive competitiveness and lack of teaching for understanding. Girls' yearning for deep understanding is seen as a form of questing for connected knowledge. It is suggested that instructional methods that foster students' understanding while decreasing competitiveness in physics classes might contribute to girls' participation and performance in advanced physics classes while also supporting the learning of many boys.

OBJECTIVES: The aim was to construct and validate a gender-specific job exposure matrix (JEM) for physical exposures to be used in epidemiological studies of low back pain (LBP).

MATERIALS AND METHODS: We utilized two large Finnish population surveys, one to construct the JEM and another to test matrix validity. The exposure axis of the matrix included exposures relevant to LBP (heavy physical work, heavy lifting, awkward trunk posture and whole body vibration) and exposures that increase the biomechanical load on the low back (arm elevation) or those that in combination with other known risk factors could be related to LBP (kneeling or squatting). Job titles with similar work tasks and exposures were grouped. Exposure information was based on face-to-face interviews. Validity of the matrix was explored by comparing the JEM (group-based) binary measures with individual-based measures. The predictive validity of the matrix against LBP was evaluated by comparing the associations of the group-based (JEM) exposures with those of individual-based exposures.

RESULTS: The matrix includes 348 job titles, representing 81% of all Finnish job titles in the early 2000s. The specificity of the constructed matrix was good, especially in women. The validity measured with kappa-statistic ranged from good to poor, being fair for most exposures. In men, all group-based (JEM) exposures were statistically significantly associated with one-month prevalence of LBP. In women, four out of six group-based exposures showed an association with LBP.

CONCLUSIONS: The gender-specific JEM for physical exposures showed relatively high specificity without compromising sensitivity. The matrix can therefore be considered as a valid instrument for exposure assessment in large-scale epidemiological studies, when more precise but more labour-intensive methods are not feasible. Although the matrix was based on Finnish data we foresee that it could be applicable, with some modifications, in other countries with a similar level of technology.