2,205 research outputs found
Computer programs for thermodynamic and transport properties of hydrogen
Computer program subroutines provide the thermodynamic and transport properties of hydrogen in tabular form. The programs provide 18 combinations of input and output variables. This program is written in FORTRAN 4 for use on the IBM 7044 or CDC 3600 computers
Structure and Dynamics of amorphous Silica Surfaces
We use molecular dynamics computer simulations to study the equilibrium
properties of the surface of amorphous silica. Two types of geometries are
investigated: i) clusters with different diameters (13.5\AA, 19\AA, and
26.5\AA) and ii) a thin film with thickness 29\AA. We find that the shape of
the clusters is independent of temperature and that it becomes more spherical
with increasing size. The surface energy is in qualitative agreement with the
experimental value for the surface tension. The density distribution function
shows a small peak just below the surface, the origin of which is traced back
to a local chemical ordering at the surface. Close to the surface the partial
radial distribution functions as well as the distributions of the bond-bond
angles show features which are not observed in the interior of the systems. By
calculating the distribution of the length of the Si-O rings we can show that
these additional features are related to the presence of two-membered rings at
the surface. The surface density of these structures is around 0.6/nm^2 in good
agreement with experimental estimates. From the behavior of the mean-squared
displacement at low temperatures we conclude that at the surface the cage of
the particles is larger than the one in the bulk. Close to the surface the
diffusion constant is somewhat larger than the one in the bulk and with
decreasing temperature the relative difference grows. The total vibrational
density of states at the surface is similar to the one in the bulk. However, if
only the one for the silicon atoms is considered, significant differences are
found.Comment: 30 pages of Latex, 16 figure
Uniform data system standardizes technical computations and the purchasing of commercially important gases
Integrated tables of pressure, volume, and temperature for the saturated liquid, from the triple point to the critical point of the gases, have been developed. Tables include definition of saturated liquid curve. Values are presented in metric and practical units. Advantages of the new tables are discussed
One-Year Randomized Controlled Trial and Follow-Up of Integrated Neurocognitive Therapy for Schizophrenia Outpatients
Objective: Cognitive remediation (CR) approaches have demonstrated to be effective in improving cognitive functions in schizophrenia. However, there is a lack of integrated CR approaches that target multiple neuro- and social-cognitive domains with a special focus on the generalization of therapy effects to functional outcome. Method: This 8-site randomized controlled trial evaluated the efficacy of a novel CR group therapy approach called integrated neurocognitive therapy (INT). INT includes well-defined exercises to improve all neuro- and social-cognitive domains as defined by the Measurement And Treatment Research to Improve Cognition in Schizophrenia (MATRICS) initiative by compensation and restitution. One hundred and fifty-six outpatients with a diagnosis of schizophrenia or schizoaffective disorder according to DSM-IV-TR or ICD-10 were randomly assigned to receive 15 weeks of INT or treatment as usual (TAU). INT patients received 30 bi-weekly therapy sessions. Each session lasted 90min. Mixed models were applied to assess changes in neurocognition, social cognition, symptoms, and functional outcome at post-treatment and at 9-month follow-up. Results: In comparison to TAU, INT patients showed significant improvements in several neuro- and social-cognitive domains, negative symptoms, and functional outcome after therapy and at 9-month follow-up. Number-needed-to-treat analyses indicate that only 5 INT patients are necessary to produce durable and meaningful improvements in functional outcome. Conclusions: Integrated interventions on neurocognition and social cognition have the potential to improve not only cognitive performance but also functional outcome. These findings are important as treatment guidelines for schizophrenia have criticized CR for its poor generalization effect
Sugar-sweetened beverage consumption, correlates and interventions among Australian Aboriginal and Torres Strait Islander communities: a scoping review protocol
Introduction: Aboriginal and Torres Strait Islander communities of Australia experience poorer health outcomes in the areas of overweight and obesity, diabetes and cardiovascular disease. Contributing to this burden of disease in the Australian community generally and in Aboriginal and Torres Strait Islander communities, is the consumption of sugar-sweetened beverages (SSBs). We have described a protocol for a review to systematically scope articles that document use of SSBs and interventions to reduce their consumption with Aboriginal and Torres Strait Islander people. These results will inform future work that investigates interventions aimed at reducing harm associated with SSB consumption. Methods and analysis: This scoping review draws on a methodology that uses a six-step approach to search databases including PubMed, SCOPUS, CINAHL, Informit (including Informit: Indigenous Peoples), Joanna Briggs Institute EBP Database and Mura, between January 1980 and February 2017. Two reviewers will be engaged to search for and screen studies independently, using formulated selection criteria, for inclusion in our review. We will include primary research studies, systematic reviews including meta-analysis or meta-synthesis, reports and unpublished grey literature. Results will be entered into a table identifying study details and characteristics, summarised using a Preferred Reporting Items for Systematic Reviews and Meta-Analysis chart and then critically analysed. Ethics and dissemination: This review will not require ethics committee review. Results will be disseminated at appropriate scientific meetings, as well as through the Aboriginal and Torres Strait Islander community.Jodie C Avery, Jacqueline A Bowden, Joanne Dono, Odette R Gibson, Aimee Brownbill, Wendy Keech, David Roder, Caroline L Mille
Transport Properties of the One Dimensional Ferromagnetic Kondo Lattice Model : A Qualitative Approach to Oxide Manganites
The transport properties of the ferromagnetic Kondo lattice model in one
dimension are studied via bosonization methods. The antiferromagnetic
fluctuations, which normally appear because of the RKKY interactions, are
explicitly taken into account as a direct exchange between the ``core'' spins.
It is shown that in the paramagnetic regime with the local antiferromagnetic
fluctuations, the resistivity decays exponentially as the temperature increases
while in the ferromagnetic regime the system is an almost perfect conductor. %A
non-perturbative description of localized spin polarons %in the paramagnetic
region is obtained.
The effect of a weak applied field is discussed to be reduced to the case of
the ferromagnetic state leading to band splitting. The qualitative relevance of
the results for the problem of the Oxide Manganites is emphasized.Comment: 4 pages, REVTe
A robot trace maker: modeling the fossil evidence of early invertebrate behavior.
The study of trace fossils, the fossilized remains of animal behavior, reveals interesting parallels with recent research in behavior-based robotics. This article reports robot simulations of the meandering foraging trails left by early invertebrates that demonstrate that such trails can be generated by mechanisms similar to those used for robot wall-following. We conclude with the suggestion that the capacity for intelligent behavior shown by many behavior-based robots is similar to that of animals of the late Precambrian and early Cambrian periods approximately 530 to 565 million years ago
Glass Transition in the Polaron Dynamics of CMR Manganites
Neutron scattering measurements on a bilayer manganite near optimal doping
show that the short-range polarons correlations are completely dynamic at high
T, but then freeze upon cooling to a temperature T* 310 K. This glass
transition suggests that the paramagnetic/insulating state arises from an
inherent orbital frustration that inhibits the formation of a long range
orbital- and charge-ordered state. Upon further cooling into the
ferromagnetic-metallic state (Tc=114 K), where the polarons melt, the diffuse
scattering quickly develops into a propagating, transverse optic phonon.Comment: 4 pages, 4 figures. Physical Review Letters (in Press
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