A comparison of applied and theoretical knowledge of concepts based on the particulate nature of matter

This study compares 183 high school chemistry students' applied and theoretical knowledge of selected concepts based on the particulate theory. The concepts are dissolution, diffusion, effusion, and states of matter. A two-form instrument called the Physical Changes Concepts Test (PCCT) was developed for this study. The application form measures students' knowlege using everyday language. The theoretical form measures students' knowledge using scientific language. Students' formal reasoning ability was measured using the Test Of Logical Thinking (TOLT). The overall results of the two forms of the PCCT indicate that more than 40% of the students displayed alternative conceptions (ACs) of the concepts covered in the PCCT. The study found that students' formal reasoning ability and their preexisting knowledge are associated with their conceptions and use of the particulate theory. The analysis of the nature of students' ACs and their use of the particulate theory revealed a significant difference between students' applied and theoretical knowledge.     

Progress,innovation and regulatory science in drug development: the politics of international standard-setting

This paper examines international standard-setting in the toxicology of pharmaceuticals during the 1990s, which has involved both the pharmaceutical industry and regulatory agencies in an organization known as the International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH). The analysis shows that the relationships between innovation, regulatory science and 'progress' may be more complex and controversial than is often assumed. An assessment of the ICH's claims about the implications of 'technical' harmonization of drug-testing standards for the maintenance of drug safety, via toxicological testing, and the delivery of therapeutic progress, via innovation, is presented. By demonstrating that there is not a technoscientific validity for these claims, it is argued that, within the ICH, a discourse of technological innovation and scientific progress has been used by regulatory agencies and prominent parts of the transnational pharmaceutical industry to legitimize the lowering and loosening of toxicological standards for drug testing. The mobilization and acceptance of this discourse are shown to be pivotal to the ICH's transformation of reductions in safety standards, which are apparently against the interests of patients and public health, into supposed therapeutic benefits derived from promises of greater access to more innovative drug products. The evidence suggests that it is highly implausible that these reductions in the standards of regulatory toxicology are consistent with therapeutic progress for patients, and highlights a worrying aspect embedded in the 'technical trajectories' of regulatory science.     

Impact of iodine deficiency on thyroid function in pregnant African women — A possible factor in the genesis of ‘small for dates’ babies

The effect of iodine deficiency (ID) on thyroid function in African women during pregnancy and postnatal period was examined, for which very limited information is available. Serum T₄, T₃, TSH, TBG, thyroxine binding capacity (TBK), free thyroxine index (FT₄I=T₄/TBK) and T₄/TBG were determined by ELISA technique in 32 pregnant women (resident of Plateau state, Nigeria- an ID zone) through pregnancy upto term delivery, and in 5 women up to 6 weeks post delivery. Urinary iodide level was measured at delivery to determine the degree of iodine deficiency. Results were matched with a non pregnant control comprising 44 subjects. 5555 birth weights (BW) of term babies in the region were analysed to determine the prevalence of ‘small for dates’ (SFD) babies in the population. Results show that the level of serum FT₄I was elevated very significantly at late gestation (P<.001) but the women were not hyperthyroid, suggesting a marked disturbance in binding of T₄ with TBG during pregnancy. Five women with SFD babies were found in ‘compensated hypothyroid state’ and showed a significant depression (p<.01) in serum T₄/TBG, T₄, FT₄I and T₃ levels to a low normal range, with a concurrent significant rise (p.<.001) in TSH level (above normal range) throughout pregnancy. Incidence of SFD babies was higher (p.<.001) in ID zone (Bassa 15.2%) compared to control zone (Jos 9.8%). It is concluded that a state of maternal ‘subclinical (compensated) hypothyroidism’ during pregnancy possibly plays an important role in the aetiopathogenesis of SFD babies in Africans. A normal reference range for thyroid parameters at various stages of pregnancy in healthy African women is established for the first time.     

When the most “pertinent” document should not be retrieved—An analysis of the Swets model

Most automated information retrieval systems operate by relating a document to a request by means of a measure of pertinance, and then retrieving the most pertinent documents for their patrons. In this paper the consistency of this operating procedure with the well known Swets Model is examined. It is shown that accepting the assumptions made by Swets would result in the possible rejection of the most pertinent documents in favor of those that are less pertinent. This conclusion is a consequence of the normality assumptions of the model, while other distributions, such as the Poisson distribution, is consistent with the standard procedure. In the course of the development, the fundamentals of decision theory and signal detection theory are reviewed.     

δ-ALA levels in serum and urine—A diagnostic tool for possible lead poisoning

We present 2 cases of lead poisoning, the first of a child playing with painted toys and the second of an adult on local medicine. The former presented with acute abdomen and the latter with peripheral muscle weakness. We propose that raised serum δ-amino leavulinic acid (δ-ALA) levels strongly point towards the possibility of lead poisoning.     

Visualising Famagusta: interdisciplinary approaches to the study of the Orthodox Cathedral of Saint George of the Greeks in Famagusta,Cyprus

This paper explores a recent interdisciplinary project which brought together a visualization expert, an art historian, and an architectural historian, to study the ruins of Saint George of the Greeks Cathedral in Famagusta, eastern Cyprus, then create a virtual three-dimensional reconstruction of it. The motivation for this work, funded by Nanyang Technological University in Singapore, was to apply existing knowledge and expertise to a difficult, and very particular, heritage question on this Eastern Mediterranean Island. The creation of such a model could, it was felt, not only reiterate the academic value of thorough archival work married to state of the art technology, but also have very practical reverberations in terms of future heritage welfare and education via this ‘borderless’ domain.     

Design,implementation and evaluation of school-based sexual health education in sub-Saharan Africa: a qualitative study of researchers’ perspectives

This study investigated facilitators and challenges to designing, implementing and evaluating school-based sexual health education in sub-Saharan Africa, using interviews with intervention designers and researchers. At the pre-planning and planning stages, participants reported that facilitating factors included addressing the reproductive health needs of participants, contextual (culture, religion, economic and social) considerations and the adoption of holistic approach to sexuality education. Lack of open communication about sexual health matters between young people and adults; concerns that sexual health education could encourage sexual activity; and inadequate funding, were key barriers. Implementation was facilitated by the involvement of relevant stakeholders, the training of facilitators and adopting strategies to overcome resistance to sexual health education. The provision of structured, detailed lessons plans and monitoring with supportive supervision optimised fidelity of delivery. Barriers to implementation included facilitators’ resistance to teaching safe sex promotion and logistical challenges in school environments. Participants also reported that the validity of self-reported adolescent sexual behaviour (as part of evaluation) may be improved by complementing well-designed self-report surveys with computerised audio devices for data collection, qualitative interviews and participant observation. Study findings generate recommendations to improve future forms of school-based sexual health education in sub-Saharan Africa.