Correction of the copper transport defect of Menkes patient fibroblasts by expression of two forms of the sheep Wilson ATPase

The Wilson disease (WD) protein (ATP7B) is a copper-transporting P-type ATPase that is responsible for the efflux of hepatic copper into the bile, a process that is essential for copper homeostasis in mammals. Compared with other mammals, sheep have a variant copper phenotype and do not efficiently excrete copper via the bile, often resulting in excessive copper accumulation in the liver. To investigate the function of sheep ATP7B and its potential role in the copper-accumulation phenotype, cDNAs encoding the two forms of ovine ATP7B were transfected into immortalised fibroblast cell lines derived from a Menkes disease patient and a normal control. Both forms of ATP7B were able to correct the copper-retention phenotype of the Menkes cell line, demonstrating each to be functional copper-transporting molecules and suggesting that the accumulation of copper in the sheep liver is not due to a defect in the copper transport function of either form of sATP7B.

Challenges in translating scientific evidence into mandatory food fortification policy: an antipodean case study of the folate- neural tube defect relationship

Objective: To identify challenges in translating scientific evidence of a  nutrient and health relationship into mandatory food fortification policy.
Design: A case study approach was used in which available evidence  associated with the folate–neural tube defect relationship was reviewed against the Australia New Zealand Food Regulation Ministerial Council's Policy Guideline for mandatory food fortification. Results: Three particular challenges were identified. The first is knowing when and how to act in the face of scientific uncertainty. The second is knowing how to address the special needs of at-risk individuals without compromising the health and safety of the population as a whole. The third is to ensure that a policy is sufficiently monitored and evaluated. Conclusions: Despite the availability of compelling evidence of a relationship between a particular nutrient and a health outcome, a definitive policy response may not be apparent.  Judgement and interpretation inevitably play significant roles in influencing whether and how authorities translate scientific evidence into mandatory food fortification policy. In relation to the case study, it would be prudent to undertake a risk–benefit analysis of policy alternatives and to implement nutrition education activities to promote folic acid supplement use among the target group. Should mandatory folate fortification be implemented,  comprehensive monitoring and evaluation of this policy will be essential to know that it is implemented as planned and does more good than harm. In relation to mandatory food fortification policy-making around the world,  ongoing national nutrition surveys are required to complement national policy guidelines.

Evalutaion of the implementation of the folate-neural tube defect health claim and its impact on the availability of folate-fortified food in Australia

Objective: To evaluate the implementation of the folate-neural tube defect (NTD) health claim and its impact on the availability of folate-fortifed food in Australia.

Methods: During late 2005, a survey was conducted in 16 supermarkets across all Australian capital cities to identify the use of the folate-NTD health claim on the labels of the 128 food products listed in food standard 1.1A.2: 'Transitional standard - Health claims' and the number of products fortifed with folic acid.

Results: Seventy-nine per cent of existing listed food products were found and two of these were implementing the folate-NTD health claim. Forty-four per cent of these listed products, previously fortifed with folic acid, were no longer fortifed. One hundred and seventeen generally available food products were fortifed with folic acid, predominantly breakfast cereals (73%). Twenty-seven per cent of these folate-fortifed products were listed in the transitional standard.

Conclusions: The health claim was not used widely to inform women of child-bearing age of the importance of periconceptional folate intake. The increased availability of folate-fortifed products generally has occurred independently of the health claim. Defciencies in the verifcation system of the tested regulatory framework are identifed. The voluntary regulatory provisions for both folate fortifcation and the use of the health claim diminished the States' infuence over their implementation of public health tools.

Investigation of effective material properties in composites with internal defect or reinforcement particles

This paper is concerned with the investigation of the effective material properties of internally defective or particle-reinforced composites. An analysis was carried out with a novel method using the two-dimensional special finite element method mixing the concept of equivalent homogeneous materials. A formulation has been developed for a series of special finite elements containing an internal defect or reinforcement in order to assure the high accuracy especially in the vicinity of defects or reinforcements. The adoption of the special finite element can greatly simplify numerical modeling of particle-composites. The numerical result provides the effective material properties of particle-reinforced composite and explains that the size of particles has great influence on the material properties. Numerical examples also demonstrate the validity and versatility of the proposed method by comparing with existing results from literatures.

Improving the quality of die castings by using artificial neural networks for porosity defect modelling

The aim of this work is to improve the quality of castings by minimizing defects and scrap through the analysis of the data generated by High Pressure Die Casting (HPDC) Machines using computational intelligence techniques. Casting is a complex process that is affected by the interdependence of die casting process parameters on each other such that changes in one parameter results in changes in other parameters. Computational intelligence techniques have the potential to model accurately this complex relationship. The project has the potential to generate optimal configurations for HPDC Machines and explain the relationships between die casting process parameters.

Direct observation of defect levels in hexagonal BN by soft X-ray absorption spectroscopy

Formation of defects in hexagonal boron nitride under low-energy argon bombardment has been studied by near-edge X-ray absorption fine structure (NEXAFS) around B and N K-edges. Breaking of B-N bonds and creation of nitrogen vacancies has been identified from the B K-edge, followed by the formation of molecular nitrogen, N2, at interstitial positions. The presence of N2 produces a sharp resonance in the low-resolution NEXAFS spectra around N K-edge, showing the characteristic vibrational fine structure in high-resolution measurements. Several new peaks in NEXAFS spectra have been assigned to boron or nitrogen interstitials, in good agreement with theoretical predictions. © 2009 Elsevier B.V. All rights reserved.

Nanoparticle enhanced conductivity in organic ionic plastic crystals : space charge versus strain induced defect mechanism

High conductivity in solid-state electrolytes is a critical requirement for many advanced energy and other electrochemical applications. Plastic crystalline materials have shown promise in this regard, and the inclusion of nanosized inorganic particles in both amorphous and crystalline materials has indicated order of magnitude enhancements in ion transport induced by space charge or other defect enhancement. In this paper we present conductivity enhancements in the plastic crystal N,N‘-ethylmethylpyrrolidinium bis(trifluoromethanesulfonyl)amide ([C₂mpyr][NTf₂]) induced by nanosized SiO₂ particles. The addition of the nanoparticles dramatically increases plasticity and ion mobility. Positron annihilation lifetime spectroscopy (PALS) measurements indicate an increase in mean defect size and defect concentration as a result of nanoparticle inclusion. The scaling of the conductivity with size suggests that a “trivial space charge” effect is operable, although a strain induced enhancement of defects (in particular extended defects) is also likely given the observed increase in plasticity.

Defect assessment procedures for high temperature applications : final report TW5-TTMS-005, D5

The objective of this task is to develop the high temperature part of a design code for fusion reactor components build from EUROFER. This development includes fracture mechanical rules for the assessment of detected defects under creep and creep–fatigue conditions. The assessment procedures R5, R6, JNC, A16, Partial Safety Factors were investigated and tested. As the most suitable procedure is chosen R5 and it is further verified by comparison with finite element simulations using the EUROFER material data. These simulations consist of evaluation of C(t) parameter for several geometries (CT specimen,cylinder with fully circumferential crack subjected to the internal pressure, cylinder with semi–elliptical circumferential crack subjected to the internal pressure and Mock-Up test blanket module (TBM) geometry). The R5 procedure provides very good accordance with FE simulations and it is suitable for lifetime assessment. Therefore the guide for R5 application is implemented in the report.