Approaches used to estimate bioavailability when deriving dietary reference values for iron and zinc in adults

This review aims to describe approaches used to estimate bioavailability when deriving dietary reference values (DRV) for iron and zinc using the factorial approach. Various values have been applied by different expert bodies to convert absorbed iron or zinc into dietary intakes, and these are summarised in this review. The European Food Safety Authority (EFSA) derived zinc requirements from a trivariate saturation response model describing the relationship between zinc absorption and dietary zinc and phytate. The average requirement for men and women was determined as the intercept of the total absorbed zinc needed to meet physiological requirements, calculated according to body weight, with phytate intake levels of 300, 600, 900 and 1200 mg/d, which are representative of mean/median intakes observed in European populations. For iron, the method employed by EFSA was to use whole body iron losses, determined from radioisotope dilution studies, to calculate the quantity of absorbed iron required to maintain null balance. Absorption from the diet was estimated from a probability model based on measures of iron intake and status and physiological requirements for absorbed iron. Average dietary requirements were derived for men and pre- and post-menopausal women. Taking into consideration the complexity of deriving DRV for iron and zinc, mainly due to the limited knowledge on dietary bioavailability, it appears that EFSA has made maximum use of the most relevant up-to-date data to develop novel and transparent DRV for these nutrients

Success factors in new land-based industries

Part of the changing structure of New Zealand agriculture and horticulture includes a move from traditional land uses to new land uses. Not all new land uses, however, become established industries. The research objective of this study was to focus on a wide range of new land-based industries and address the question of why some new industries succeed and why others do not. The research also introduces a relatively new method, the Qualitative Comparative Analysis method, which identifies critical factors in industry success in a way that combines the richness of case studies with the rigour of comparative analysis. Results will be of interest to primary producers seeking to learn from recent experience of new industries, and to policy-makers interested in promoting new land-based industries.Funding for this research was provided by the Foundation for Research, Science, and Technology, via Crop and Food Research under Contract No. C02810 and entitled New Crops

Characteristics of smallholdings in New Zealand : results from a nationwide survey

This research investigated land use and the social and environmental effects of smallholding. The research was designed to provide a comprehensive understanding of smallholders and smallholdings by means of a nationwide survey. To conduct the survey a sample of 3,934 cases was randomly selected from the smallholding population of 0.04 to 40 hectares in size. The survey derived 947 usable responses with a revised response rate of 28 per cent. Analysis of the survey data was undertaken using three categories of smallholder. This analysis showed some differences between the lifestyler, hobby/smallfarmer and farmer/horticulturalist. There were noticeable differences, for example, in size, number of years of residence and amount of farm experience. However, there were no differences in terms of engagement in productive activities such as livestock and plant production. In further analysis it was found that almost all smallholders intend to plant trees for landscaping or commercial purposes. However, the analysis also showed that smallholders do not voluntarily engage in environmental monitoring and environmentally friendly practices to the same extent as other farmers and growers. In addition, the use of, and intentions to use, organic methods were not as prevalent as that for other farmers and growers. Nevertheless, it was also found that smallholders valued the merits of country life including peace and quiet and clean air. In discussion of the results emphasis is given to production and it is shown that while there appears to be high levels of production on some of the smallholdings the result is skewed by a small number of smallholders with high production income, while a sizable proportion did not report any income. Lack of difference between self declared lifestylers and other smallholders is discussed in terms of the common assumption that lifestylers engage less in farming activities. A discussion of environmental impacts predicts a 'greening' of the landscape due to smallholders' intending to plant various tree varieties

A Two-Dimensional, Finite-Difference Model of the Oxidation of a Uranium Carbide Fuel Pellet

The oxidation of spent uranium carbide fuel, a candidate fuel for Generation IV nuclear reactors, is an important process in its potential reprocessing cycle. However, the oxidation of uranium carbide in air is highly exothermic. A model has therefore been developed to predict the temperature rise, as well as other useful information such as reaction completion times, under different reaction conditions in order to help in deriving safe oxidation conditions. Finite difference-methods are used to model the heat and mass transfer processes occurring during the reaction in two dimensions and are coupled to kinetics found in the literature

Numerical modelling of turbulent particle-laden sonic CO2 jets with experimental validation

Under-expanded particle-laden flows resulting in velocities greater than the local speed of sound are a feature of a wide number of applications in aviatic, astronautical, and process engineering scenarios including those relating to the accidental release of high-pressure fluids from reservoirs or pipelines. Such pipelines are considered to be the most likely method for transportation of captured carbon dioxide (CO2) from power plants and other industries prior to subsequent storage in carbon capture and storage (CCS) applications. Their safe operation is of paramount importance as their contents are likely to be in the region of several thousand tonnes. CO2 poses a number of dangers upon release due to its physical properties. It is a colourless and odourless asphyxiant which has a tendency to sublimation and solid formation, and is directly toxic if inhaled in air at concentrations around 5%, and likely to be fatal at concentrations around 10%. The developments presented in this paper concern the formulation of a multi-phase homogeneous discharge and dispersion model capable of predicting the near-field fluid dynamic, phase and particle behaviour of such CO2 releases, with validation against measurements of laboratory-scale jet releases of CO2 recently obtained by our group

Electron microscopical study to assess the in vitro effects of the synthetic trioxolane OZ78 against the liver fluke, Fasciola hepatica

Adult Fasciola hepatica were incubated for 48 h in vitro in the synthetic peroxide, OZ78 at a concentration of 100 μg/ml and then prepared for scanning and transmission electron microscopy. There was limited disruption to the external fluke surface, with only slight swelling and blebbing of the interspinal tegument in the midbody and ventral tail regions. By contrast, significant disruption was observed to the ultrastructure of the tegument and subtegumental tissues. There was severe swelling of the basal infolds in the tegumental syncytium and the flooding spread internally to affect the subtegumental tissues. In the tegumental system, there was swelling of the cisternae of granular endoplasmic reticulum and of the mitochondria, with the latter showing signs of breaking down. Autophagic vacuoles and lipid droplets were present and the synthesis of tegumental secretory bodies was much reduced. The gastrodermal cells were severely affected, with swelling and degeneration of the mitochondria and the presence of autophagic vacuoles and lipid droplets. The granular endoplasmic reticulum was swollen and vesiculated and the cells contained few secretory bodies. Both the vitelline and testis follicles showed evidence of extensive cellular disruption and degeneration. This study confirms previous data indicating the potential flukicidal activity of OZ7

The influence of relative fluid depth on initial bedform dynamics in closed, horizontal pipe flow

Measurements of time-dependent bedforms produced by the deposition of solid plastic particles in two-phase liquid-solid flows were performed using a novel ultrasonic echo method and via video image analysis in a 100-liter, closed-pipe slurry flow loop. Results are presented for the settled bed thicknesses over a range of nominal flow rates and initial bed depths and are combined into several phase diagrams based on various combinations of parameters, with the bedforms categorized into five types. The novel observation is made that the type of bedform that arises depends on both the flow rate and the initial relative bed or fluid depth, with both ripples and dunes being observed in the same system and in a single experiment. In addition, the critical Shields number at incipient particle motion is measured to be θsc = 0.094 ± 0.043, hysteretic behavior is observed, and the evolution and scaling of each time-dependent type of bedform is analyzed in detail and compared against several expressions for initial and equilibrium dimensions from the literature. A number of universal scalings for bedforms in any type of conduit are proposed with a view ultimately to unifying the observations of bedforms in pipes with those in channels and natural flows

Determining the Metabolic Footprints of Hydrocarbon Degradation Using Multivariate Analysis

The functional dynamics of microbial communities are largely responsible for the clean-up of hydrocarbons in the environment. However, knowledge of the distinguishing functional genes, known as the metabolic footprint, present in hydrocarbon-impacted si

Engaging Undergraduates in Science Research: Not Just About Faculty Willingness.

Despite the many benefits of involving undergraduates in research and the growing number of undergraduate research programs, few scholars have investigated the factors that affect faculty members' decisions to involve undergraduates in their research projects. We investigated the individual factors and institutional contexts that predict faculty members' likelihood of engaging undergraduates in their research project(s). Using data from the Higher Education Research Institute's 2007-2008 Faculty Survey, we employ hierarchical generalized linear modeling to analyze data from 4,832 science, technology, engineering, and mathematics (STEM) faculty across 194 institutions to examine how organizational citizenship behavior theory and social exchange theory relate to mentoring students in research. Key findings show that faculty who work in the life sciences and those who receive government funding for their research are more likely to involve undergraduates in their research project(s). In addition, faculty at liberal arts or historically Black colleges are significantly more likely to involve undergraduate students in research. Implications for advancing undergraduate research opportunities are discussed