Copper transporters in the human placenta

Copper is an essential micronutrient that is particularly important during pregnancy for normal fetal development. This study determined the mechanisms by which copper is transported from the maternal circulation to the fetal circulation via the placenta and how this transport is regulated by maternal hormone levels.

Trace metal speciation in the Pieman River catchment, western Tasmania

The Pieman River catchment has seen continuous mining of economic deposits of gold, silver, lead, copper, zinc and tin since the 1870’s. Tributaries of this river which receive mining effluent, either directly or from acid mine drainage (AMID), have total metal concentrations considerably above background levels and are of regulatory concern. The lower Pieman River is however classified as a State Reserve in which recreational fishing and tourism are the major activities. It is therefore important that water entering the lower Pieman River from upstream hydroelectric impoundments is of high quality. Metals in natural waters exist in a variety of dissolved, colloidal and particulate forms. The bioavailability and hence toxicity of heavy metal pollutants is very dependant on their physico form. Knowledge of the speciation of a metal in natural aquatic environments is therefore necessary for understanding its geochemical behaviour and biological availability. Complexation of metal ions by natural ligands in aquatic systems is believed to play a significant role in controlling their chemical speciation. This study has investigated temporal and spatial variation in complexation of metal ions in the Pieman River. The influence of pH, temperature, organic matter, salinity, ionic strength and time has been investigated in a series of field studies and in laboratory-based experiments which simulated natural and anthropogenic disturbances. Labile metals were measured using two techniques in various freshwater and estuarine environments. Diffusive gradients in thin-films (DGT) allowed in situ measurement of solution speciation whilst differential pulse anodic stripping voltammetry (DPASV) was used to measure labile metal species in water samples collected from the catchment. Organic complexation was found to be a significant regulating mechanism for copper speciation and the copper-binding ligand concentration usually exceeded the total copper concentration in the river water. Complexation was highly dependent on pH and at the river-seawater interface was also regulated by salinity, probably as a result of competitive complexation by major ions in seawater (eg. Ca 2+ ions). Zinc complexation was also evident, however total zinc concentrations in the water column often far exceeded the potential binding capacity of available ligands. In addition to organic complexation, Zn speciation may also be associated with adsorption by flocculated or resuspended colloidal Mn and/or Fe oxyhydroxides. Metal ion complexation and hence speciation was found to be highly variable within the Pieman River catchment. This presents major difficulties for environmental managers, as it is therefore not possible to make catchment-wide assumptions about the bioavailability of these metals. These results emphasise the importance of site-specific sampling protocols and speciation testing, ideally incorporating continuous, in situ monitoring.

Microarray analysis for gene expression that involves trace metals

Microarray plays a major role to identify the over- and under-expressed genes. It is a well-known fact that trace elements in our body play a major role in the metabolic processes of all living organisms. In this paper, the microarray studies related to major trace metals are reviewed. This review forms the basis for the converged effort to locate the genes that are either defective and destabilise the concentration of the trace metals or influenced by the changed concentration of the trace metals that are needed for proper functions of the human body, at different parts of the body.

Dietary patterns and diet quality : approaches to assessing complex exposures in nutrition

Dietary pattern analysis provides a practical way to characterise total diet. In contrast to single food approaches, measures of dietary patterns capture interactions between food components and assist in the development of food guidelines from a public health perspective. Two main approaches to assessing dietary patterns, multivariate statistical approach and dietary indices or scores in epidemiological studies, are assessed.

Fundamental elements in examining a child’s right to education : a study of home education research and regulation in Australia

Home education provides valuable educational and developmental opportunities for children. An examination of Australia’s research indicates many best educational practices, including more informed mediation, contextualised learning, and opportunities to exercise autonomy. Key features include learning embedded in communities and program modification in response to students’ needs. Current state and territory legal requirements are examined within the context of this research and Australia’s obligations to international human rights treaties. All jurisdictions accept home education as one way to meet compulsory education requirements. The extent to which respective laws then reflect understanding of home education research and practice varies. Most jurisdictions allow for a variety of educational approaches. Some oversight regulation could however be modified to reflect a better understanding of home education. Consultation with home educators and reference to research would assist the development of more uniform legislation and policy across Australia, and enable better regulatory practice.

Critical pre-implementation elements in engendering change for sustainability in SMEs : insights from SME sustainability leaders

Despite the increased awareness surrounding sustainability issues and growing pressure on businesses to adopt sustainable business practices, there is little understanding of management processes and practices necessary for SMEs to implement environmental sustainable (ES) practices. Through qualitative in-depth interviews, this paper draws on the experiences and perspectives from twelve SME sustainability leaders to present answers to the 'what' and 'why' of critical pre-implementation elements in engendering change for sustainability within the SME context. The research questions examined in this study are: In the views of SME sustainability leaders: what pre-implementation elements are important in setting the foundations of ES success in SMEs; what are the most important elements in the decision to introduce and encourage improved ES practices; and how do SME sustainability leaders plan for ES change in their firms. We also examine how the pre-implementation elements identified in this study, fit with the steps of one of the most well-known sustainability change management frameworks by Dunphy et al (2003). The results show that elements playing a role in setting the foundations for ES success in participating firms include: the SME leader challenging the status quo, gathering of initial information; clarifying the internal know-how about ES, identifying who the ES leader(s) is, and what the associated roles are; creating a theme of environmental sustainability in the firm (what sustainability means to the firm); and the personal mindset of leaders regarding ES. In addition, it was evident from the interview data that apart from providing valuable data regarding what must change and why, the drivers and benefits of ES provide a strong rationale and motivation to the rest of the organisation why sustainability is important to the organisation. Furthermore, it is evident from the interview data that the most used strategic approach to planning by SME sustainability leaders, is a deliberate approach even though the emergent approach to planning has also featured in some SMEs. Furthermore, the CEOs are the main players in the strategic process, with the majority involving staff in planning for ES. The results also indicate that in matching the pre-implementation elements to Dunphy et al‘s (2003) sustainability change management steps, the execution of two of their steps may need adjustment to be fully applicable to SMEs. Several practical implications for other SMEs are outlined. In conclusion, the framework outlined in this paper provides an example of a critically reflective approach to a specific phase of the environmental sustainability puzzle in SMEs.