The influence of magnetic fields exposure on neurite outgrowth in PC12 rat pheochromocytoma cells

The aim of present work was to investigate the influence of magnetic fields exposure on neurite outgrowth in PC12 cells. The neurite number per cell, length of neurites and directions of neurite growth with respect to the direction of the magnetic field were analyzed after exposure to 50 Hz electromagnetic field for 96 h. A promotion was observed under a weak field (0.23 mT), as the average number of neurites per cell increased to 2.38±0.06 compared to 1.91±0.07 neurites/cell of the control dishes, while inhibition and directional outgrowth was evident under a relatively stronger field (1.32 mT). Our work shows that biological systems can be very sensitive to the strength of electromagnetic field.

Health watch exposure estimates:do they underestimate benzene exposure

A nested case–control study found that the excess of leukemia, identified among the male members of the Health Watch cohort, was associated with benzene exposure. Exposure had been retrospectively estimated for each individual occupational history using an algorithm in a relational database. Benzene exposure measurements, supplied by Australian petroleum companies, were used to estimate exposure for specific tasks. The tasks carried out within each job, the products handled, and the technology used, were identified from structured interviews with contemporary colleagues. More than half of the subjects started work after 1965 and had an average exposure period of 20 years. Exposure was low; nearly 85% of the cumulative exposure estimates were at or below 10 ppm-years. Matched analyses showed that leukemia risk increased with increasing cumulative benzene exposures and with increasing exposure intensity of the highest-exposed job. Non-Hodgkin lymphoma and multiple myeloma were not associated with benzene exposure. A reanalysis reported here, showed that for the 7 leukemia case-sets with greater than 16 ppm-years cumulative exposure, the odds ratio was 51.9 (5.6–477) when compared to the 2 lowest exposed categories combined to form a new reference category. The addition of occasional high exposures, e.g. as a result of spillages, increased exposure for 25% of subjects but for most, the increase was less than 5% of total exposure. The addition of these exposures reduced the odds ratios. Cumulative exposures did not range as high as those in comparable studies; however, the recent nature of the cohort and local handling practices can explain these differences.

Family and carer smoking control programmes for reducing children's exposure to environmental tobacco smoke

Background: Exposure to other people’s cigarette smoke (environmental tobacco smoke, or ETS) is an important child health issue.
Objectives: To determine the effectiveness of interventions aiming to reduce exposure of children to ETS.
Search strategy: The Tobacco Addiction Group register of studies was searched.MEDLINE, EMBASE and four other health and psychology databases were searched electronically, bibliographies of retrieved primary studies were checked and specialists in the area consulted.
Selection criteria: Controlled trials with or without random allocation were included in this review if they addressed participants (parents and other family members, child care workers and teachers) involved with the care and education of infants and young children (aged 0-12 years). All mechanisms for reduction of children’s environmental tobacco smoke exposure, and smoking prevention, cessation, and control programmes targeting these participants are included. These include smoke free policies and legislation, health promotion, social behavioural therapies, technology, education and clinical interventions.
Data collection and analysis: Two reviewers independently assessed studies and extracted data. Due to heterogeneity of methodologies and outcomes, no summary measures were possible and results were synthesised using narrative summaries.
Main results: Nineteen studies met the inclusion criteria, one of which was subsequently excluded. Three interventions were targeted at populations or community settings, seven studies were conducted in the well child health care setting and eight in the ill child health care setting. Twelve of these studies are from North America. In 12 of the 18 studies there was reduction of ETS exposure for children in both intervention and comparison groups. In only four of the 18 studies was there a statistically significant intervention effect. Three of these successful studies employed intensive counselling interventions targeted to smoking parents. There is little difference between the well infant, child respiratory illness and other child illness settings as contexts for parental smoking cessation interventions. The fourth successful intervention was in the school setting targeting the ETS exposure of children from smoking fathers.
Authors’ conclusions: Brief counselling interventions, successful in the adult health setting when coming from physicians, cannot be extrapolated to adults in the setting of child health. There is limited support for more intensive counselling interventions. There is no clear evidence for differences between the respiratory, non-respiratory ill child, well child and peripartum settings as contexts for reduction of children’s ETS exposure.

The evidence of harm to adults relating to exposure to extreme pornographic material: a rapid evidence assessment (REA)

This document reports on a rapid evidence assessment (REA) of the evidence of harm to adults relating to exposure to extreme pornographic materials.

The evidence of harm to adults relating to exposure to extreme pornographic material : a rapid evidence assessment (REA)

This document reports on a rapid evidence assessment (REA) of the evidence of harm to adults relating to exposure to extreme pornographic materials

Deterministic versus stochastic quantitative microbial Risk Assessment models for wastewater irrigation of food crops

Reuse of wastewater to irrigate food crops is being practiced in many parts of the world and is becoming more commonplace as the competition for, and stresses on, freshwater resources intensify. But there are risks associated with wastewater irrigation, including the possibility of transmission of pathogens causing infectious disease, to both workers in the field and to consumers buying and eating produce irrigated with wastewater. To manage these risks appropriately we need objective and quantitative estimates of them. This is typically achieved through one of two modelling approaches: deterministic or stochastic. Each parameter in a deterministic model is represented by a single value, whereas in stochastic models probability functions are used. Stochastic models are theoretically superior because they account for variability and uncertainty, but they are computationally demanding and not readily accessible to water resource and public health managers. We constructed models to estimate risk of enteric virus infection arising from the consumption of wastewater-irrigated horticultural crops (broccoli, cucumber and lettuce), and compared the resultant levels of risk between the deterministic and stochastic approaches. Several scenarios were tested for each crop, accounting for different concentrations of enteric viruses and different lengths of environmental exposure (i.e. the time between the last irrigation event and harvest, when the viruses are liable to decay or inactivation). In most situations modelled the two approaches yielded similar estimates of risk (within 1 order-of-magnitude). The two methods diverged most markedly, up to around 2 orders-of-magnitude, when there was large uncertainty associated with the estimate of virus concentration and the exposure period was short (1 day). Therefore, in some circumstances deterministic modelling may offer water resource managers a pragmatic alternative to stochastic modelling, but its usefulness as a surrogate will depend upon the level of uncertainty in the model parameters.

Scenarios as springboards for reflection on practice : stimulating discussion

Increasingly there is an expectation that new graduates will have developed, prior to their induction into teaching, sound theoretical knowledge in relation to practice. However, in Australia, many pre-service teachers have insufficient time in the field to develop reflective practice and to observe how experienced teachers enhance their own knowledge through reflection on practice. In this article we discuss one way to introduce teacher education students to the notion of reflective practice. We explore the potential of scenarios to develop reflective thinking in pre-service teacher education students and highlight the processes and requisite criteria for developing scenarios that capture the rich and complex experiences of classroom practitioners. The scenario presented here has been fashioned from a pre-service teacher's story of classroom practice collected from her during an interview for a research project. While the scenario was intended for use only with pre-service teachers in order to increase their knowledge-base and analytical skills, when it was trialled with a group of experienced teachers in order to ascertain its suitability for novice teachers, an unexpected outcome was that it resonated with the teachers in ways that enabled them also to reflect more deeply on their professional practices. We speculate that the processes of scenario construction may also be valuable in other settings where reflective practice is a professional requisite.

Enacting problem based classroom scenarios through forum theatre

While the school based practicum experience is a vital aspect of teacher education, a 'simulated' classroom can provide a less confrontational space for teacher education students to implement new teaching strategies and techniques. The project used actors to generate a series of short scenarios that dramatise classroom problems. The project employed the methodology of applied theatre in an educational setting.