Introducing education for sustainable development in the undergraduate laboratory: quantitative analysis of bioethanol fuel and its blends with gasoline by using solvatochromic dyes

The concept of Education for Sustainable Development, ESD, has been introduced in a period where chemistry education is undergoing a major change, both in emphasis and methods of teaching. Studying an everyday problem, with an important socio-economic impact in the laboratory is a part of this approach. Presently, the students in many countries go to school in vehicles that run, at least partially, on biofuels; it is high time to let them test these fuels. The use of renewable fuels is not new: since 1931 the gasoline sold in Brazil contains 20 to 25 vol-% of bioethanol; this composition is being continually monitored. With ESD in mind, we have employed a constructivist approach in an undergraduate course, where UV-vis spectroscopy has been employed for the determination of the composition of two fuel blends, namely, bioethanol/water, and bioethanol/gasoline. The activities started by giving a three-part quiz. The first and second ones introduced the students to historical and practical aspects of the theme (biofuels). In the third part, we asked them to develop a UV-vis experiment for the determination of the composition of fuel blends. They have tested two approaches: (i) use of a solvatochromic dye, followed by determination of fuel composition from plots of the empirical fuel polarity versus its composition; (ii) use of an ethanol-soluble dye, followed by determination of the blend composition from a Beer's law plot; the former proved to be much more convenient. Their evaluation of the experiment was highly positive, because of the relevance of the problem; the (constructivist) approach employed, and the bright colors that the solvatochromic dye acquire in these fuel blends. Thus ESD can be fruitfully employed in order to motivate the students; make the laboratory "fun", and teach them theory (solvation). The experiments reported here can also be given to undergraduate students whose major is not chemistry (engineering, pharmacy, biology, etc.). They are low-cost and safe to be introduced at high-school level.

Construction and validation of an instrument that breaks the silence: the impact of domestic and/or sexual violence on women's health, as shown during climacterium

Objective: The aim of this study was to construct and to validate a measure of the consequences of domestic violence on women's health during climacterium. Methods: A questionnaire was administered at the Outpatient Climacterium Clinic to 124 women aged 40 to 65 years who were the victims of domestic and/or sexual violence (experimental group). They were divided into three groups: (1) those who were victims of violence exclusively during childhood/adolescence, (2) those who were victims of violence exclusively during adulthood, and (3) those who were victims of violence throughout their lives. The instrument included 34 items evaluating the beginning, frequency, and type of violence; the search for health assistance and reporting of the violence; the violence and the number of comorbidities; and violence and the Kupperman Menopausal Index. We also included a control group composed of perimenopausal and postmenopausal women who did not experience any violence (n = 120). Results: The instrument presented a Cronbach alpha = 0.82, good reliability among the examiners (+0.80), and a good possibility of reproducibility. The mean age of menopause was 45.4 years, and the mean age in the control group was 48.1 years. Group 1 showed a mean of 5.1 comorbidities, Group 2 had 4.6, and Group 3 had 4.4. Sexual violence (43.5%) and other types of violence both presented average comorbidities (4.60) but represented a significant impairment in the victim's sexual life. There were significant associations in group 3 and a high Kupperman Menopausal Index score. In the experimental group, 80.6% did not seek health services for the violence they experienced. Conclusions: The questionnaire presented good internal consistency and a validated construction. It can be easily reproduced and is indicated to evaluate the consequences of domestic and/or sexual violence on women's health during climacterium.