8,185 research outputs found
High temperature properties of sodium, potassium, and cesium thirteenth progress report
Thermophysical properties of sodium, potassium, and cesium at high temperatures - density of liquid potassium and vapor pressure of cesiu
Brayton-cycle radioisotope heat-source design study. Phase II /preliminary design/ report
Brayton cycle radioisotope heat source desig
Loop quantum cosmology of Bianchi type IX models
The loop quantum cosmology "improved dynamics" of the Bianchi type IX model
are studied. The action of the Hamiltonian constraint operator is obtained via
techniques developed for the Bianchi type I and type II models, no new input is
required. It is shown that the big bang and big crunch singularities are
resolved by quantum gravity effects. We also present the effective equations
which provide modifications to the classical equations of motion due to quantum
geometry effects.Comment: 20 page
ADOPT: a tool for predicting adoption of agricultural innovations
A wealth of evidence exists about the adoption of new practices and technologies in agriculture but there does not appear to have been any attempt to simplify this vast body of research knowledge into a model to make quantitative predictions across a broad range of contexts. This is despite increasing demand from research, development and extension agencies for estimates of likely extent of adoption and the likely timeframes for project impacts. This paper reports on the reasoning underpinning the development of ADOPT (Adoption and Diffusion Outcome Prediction Tool). The tool has been designed to: 1) predict an innovation‘s likely peak extent of adoption and likely time for reaching that peak; 2) encourage users to consider the influence of a structured set of factors affecting adoption; and 3) engage R, D & E managers and practitioners by making adoptability knowledge and considerations more transparent and understandable. The tool is structured around four aspects of adoption: 1) characteristics of the innovation, 2) characteristics of the population, 3) actual advantage of using the innovation, and 4) learning of the actual advantage of the innovation. The conceptual framework used for developing ADOPT is described.Adoption, Diffusion, Prediction, Research and Development/Tech Change/Emerging Technologies,
Preferences for support services among adolescents and young adults with cancer or a blood disorder: A discrete choice experiment
Background: Life-threatening illnesses in young people are traumatic for patients and their families. Support services can help patients and families deal with various non-medical impacts of diagnosis, disease and treatment. The aim of this study was to determine which types of support are most valued by adolescents and young adults (AYA) with cancer or blood disorders and their families. Method: A discrete choice experiment (DCE). Separate experiments were conducted with AYA and their carers. Results: Completed surveys were returned by 83 patients and 78 carers. AYA preferred emotional support for themselves (either by counsellors and/or peers), emotional support for their family, financial support and assistance returning to school/work over services relating to cultural and spiritual needs. Covariate analysis indicated female AYA were more likely than males to prefer emotional support, while males were more likely to prefer assistance returning to work/school. Carers preferred emotional support for their AYA and assistance returning to school/work. Like AYA, they were indifferent about services relating to cultural and spiritual needs. Conclusion: Providing the types of support services that people prefer should maximise effectiveness. This study suggests that AYA patients require support services that included financial aid, assistance returning to work/study, emotional support for themselves and for their family. © 2012 Elsevier Ireland Ltd
Assessment of culture and environment in the Adolescent Brain and Cognitive Development Study: Rationale, description of measures, and early data.
Neurodevelopmental maturation takes place in a social environment in addition to a neurobiological one. Characterization of social environmental factors that influence this process is therefore an essential component in developing an accurate model of adolescent brain and neurocognitive development, as well as susceptibility to change with the use of marijuana and other drugs. The creation of the Culture and Environment (CE) measurement component of the ABCD protocol was guided by this understanding. Three areas were identified by the CE Work Group as central to this process: influences relating to CE Group membership, influences created by the proximal social environment, influences stemming from social interactions. Eleven measures assess these influences, and by time of publication, will have been administered to well over 7,000 9-10 year-old children and one of their parents. Our report presents baseline data on psychometric characteristics (mean, standard deviation, range, skewness, coefficient alpha) of all measures within the battery. Effectiveness of the battery in differentiating 9-10 year olds who were classified as at higher and lower risk for marijuana use in adolescence was also evaluated. Psychometric characteristics on all measures were good to excellent; higher vs. lower risk contrasts were significant in areas where risk differentiation would be anticipated
Qualitative study in Loop Quantum Cosmology
This work contains a detailed qualitative analysis, in General Relativity and
in Loop Quantum Cosmology, of the dynamics in the associated phase space of a
scalar field minimally coupled with gravity, whose potential mimics the
dynamics of a perfect fluid with a linear Equation of State (EoS). Dealing with
the orbits (solutions) of the system, we will see that there are analytic ones,
which lead to the same dynamics as the perfect fluid, and our goal is to check
their stability, depending on the value of the EoS parameter, i.e., to show
whether the other orbits converge or diverge to these analytic solutions at
early and late times.Comment: 12 pages, 7 figures. Version accepted for publication in CQ
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