Electron beam chemistry produces high purity metals

Application of radiation chemistry for deposition of metals by irradiation of aqueous solutions with high energy electrons is presented. Design of reaction vessel for irradiation of solution is illustrated. Features of radiochemical technique and procedures followed are described

What makes a 'good group'? Exploring the characteristics and performance of undergraduate student groups

Group work forms the foundation for much of student learning within higher education, and has many educational, social and professional benefits. This study aimed to explore the determinants of success or failure for undergraduate student teams and to define a ‘good group’ through considering three aspects of group success: the task, the individuals, and the team. We employed a mixed methodology, combining demographic data with qualitative observations and task and peer evaluation scores. We determined associations between group dynamic and behaviour, demographic composition, member personalities and attitudes towards one another, and task success. We also employed a cluster analysis to create a model outlining the attributes of a good small group learning team in veterinary education. This model highlights that student groups differ in measures of their effectiveness as teams, independent of their task performance. On the basis of this, we suggest that groups who achieve high marks in tasks cannot be assumed to have acquired team working skills, and therefore if these are important as a learning outcome, they must be assessed directly alongside the task output

From theory to 'measurement' in complex interventions: methodological lessons from the development of an e-health normalisation instrument

<b>Background</b> Although empirical and theoretical understanding of processes of implementation in health care is advancing, translation of theory into structured measures that capture the complex interplay between interventions, individuals and context remain limited. This paper aimed to (1) describe the process and outcome of a project to develop a theory-based instrument for measuring implementation processes relating to e-health interventions; and (2) identify key issues and methodological challenges for advancing work in this field.<p></p> <b>Methods</b> A 30-item instrument (Technology Adoption Readiness Scale (TARS)) for measuring normalisation processes in the context of e-health service interventions was developed on the basis on Normalization Process Theory (NPT). NPT focuses on how new practices become routinely embedded within social contexts. The instrument was pre-tested in two health care settings in which e-health (electronic facilitation of healthcare decision-making and practice) was used by health care professionals.<p></p> <b>Results</b> The developed instrument was pre-tested in two professional samples (N = 46; N = 231). Ratings of items representing normalisation 'processes' were significantly related to staff members' perceptions of whether or not e-health had become 'routine'. Key methodological challenges are discussed in relation to: translating multi-component theoretical constructs into simple questions; developing and choosing appropriate outcome measures; conducting multiple-stakeholder assessments; instrument and question framing; and more general issues for instrument development in practice contexts.<p></p> <b>Conclusions</b> To develop theory-derived measures of implementation process for progressing research in this field, four key recommendations are made relating to (1) greater attention to underlying theoretical assumptions and extent of translation work required; (2) the need for appropriate but flexible approaches to outcomes measurement; (3) representation of multiple perspectives and collaborative nature of work; and (4) emphasis on generic measurement approaches that can be flexibly tailored to particular contexts of study

Chaos induced coherence in two independent food chains

Coherence evolution of two food web models can be obtained under the stirring effect of chaotic advection. Each food web model sustains a three--level trophic system composed of interacting predators, consumers and vegetation. These populations compete for a common limiting resource in open flows with chaotic advection dynamics. Here we show that two species (the top--predators) of different colonies chaotically advected by a jet--like flow can synchronize their evolution even without migration interaction. The evolution is charaterized as a phase synchronization. The phase differences (determined through the Hilbert transform) of the variables representing those species show a coherent evolution.Comment: 5 pages, 5 eps figures. Accepted for publication in Phys. Rev.

INFLUENCE OF LAND TENURE ARRANGEMENTS ON GRAZING MANAGEMENT INCENTIVES

Land Economics/Use, Livestock Production/Industries,

Staining and peeling of the internal limiting membrane using a fluorescent dye (Rhodamine 6 G)

Aim: To assess whether low concentrations of a fluorescent dye such as Rhodamine 6G would help the unaided human eye visualise the vitreous and the internal limiting membrane (ILM) under standard halogen illumination.Material/methods: The UV/Vis absorption (E) and fluorescence (I) spectra of Rhodamine 6G in water were measured and compared with Indocyanine Green (ICG). Surgery was performed in two rhesus monkeys and consisted of standard pars plana vitrectomy with halogen light source used for illumination. Rhodamine 6G was diluted in balanced salt solution (BSS). A few drops of the dye in a concentration of 0.1% (307 mOsm) were applied over the posterior pole in the air-filled globe and washed out by irrigation after 1 min. Immediately after surgery, the globes were enucleated, fixated and prepared for histological evaluation.Results: In contrast to ICG, both the maximum of the absorption and emission of Rhodamin 6G are very much within the spectral sensitivity of the human eye. The Rhodamine 6G--BSS itself appears red in colour. Using a dye concentration of 0.1%, there was no visible red-staining of the ILM as such. As the dye was irrigated out with BSS, a marked green fluorescence of the fluid within the vitreous cavity was noted. With halogen illumination through a standard 20-gauge light pipe, the dye provided a sufficient green fluorescence to identify and safely remove the ILM and to clearly differentiate areas of peeled from non-peeled ILM. During light microscopy, eyes revealed a peeled ILM demarcation with no signs of acute retinal toxicity.Conclusion: The findings indicate that a fluorescent dye can be used for ILM peeling. Assuming that the fluorophore provides a high enough fluorescence quantum yield after adsorption to the ILM, much lower dye concentrations could be used compared with absorbent dyes, thereby minimising toxic effects

FACTORS INFLUENCING OPTIMAL STOCKING RATES FROM A TENANT PERSPECTIVE

The terms of grazing lease contracts potentially influence the tenants incentive to preserve the vegetation resource. Annual stocking rate decisions dictate the degree of overgrazing, which can be cumulative over long periods of time. The objective of this study is to identify the impact the tenants planning horizon and cost structure specified in the lease contract has on his/her profit-maximizing stocking rate. A multi-period nonlinear programming model was developed to identify economically optimal stocking rates each year over a 24-year period. The model was solved under 1-, 4-, 8-, and 12-year leases on a per acre and per head basis. The relative importance of each lease alternative and input variable on the tenants optimal stocking rate was ranked based on standardized ordinary least squares coefficient estimates between input values and optimal stocking rates. Planning horizon and cost structure had a minor impact on optimal stocking rates relative to non-lease factors such as livestock prices and production costs. Holding other factors constant, per acre leases generated a 2% higher average stocking rate than per head leases. Optimal stocking rates were inversely related to the length of the lease. Twelve-year lease agreements generated 18 and 13% lower optimal stocking rater than the 1-year per acre and per head lease agreements, respectively. The optimal stocking rate difference between an 8-year and a 12-year lease was negligible, suggesting the 8-year lease would provide a similar incentive to protect vegetation as a lease with a longer planning horizon.Environmental Economics and Policy, Land Economics/Use,

The UK Development Aid Programme and the British domestic economy

The effects of development aid programmes on the domestic economy of donors are relatively infrequently examined. This study reviews the impact of the United Kingdom’s Development Aid Programme on the British economy over the period 1975–79 with particular attention to employment creation and multiplier effects both in aggregate and by industrial sector. Some comparisons are made with German experience. Also examined are the types of companies which benefit from aid-financed orders, the implications for the donor’s own assisted regions and potential benefit to normal commercial trade. It is argued that a greater awareness of these effects should create a more favourable climate for the increase in aid levels

Rural/Urban Differences in Inmate Perceptions of the Punitiveness of Prison: Does Having Children Make Prison More Punitive

Many researchers have argued that an inmate’s relationship with their family is an important determinant of their behavior while incarcerated and their success in the community upon release from prison. Nevertheless, no research of which we are aware examines the impact of an inmate’s parental involvement on their perception of the punitiveness of prison while incarcerated or whether this impact varies between prisoners raised in rural or urban areas. The current study used exchange rates from more than 1200 incarcerated prisoners to examine this relationship. Our findings suggest that whether an inmate has a child has almost no impact on their perception of the punitiveness of prison, no matter whether the inmate was raised in a rural or urban area. The findings further suggest that the well-documented impact of age on perceived punitiveness of prison might be largely important among prisoners from rural areas. Implications for future research are also discussed