Diffusion dynamics of supercooled water modeled with the cage-jump motion and hydrogen-bond rearrangement

The slow dynamics of glass-forming liquids is generally ascribed to the cage-jump motion. In the cage-jump picture, a molecule remains in a cage formed by neighboring molecules, and after a sufficiently long time, it jumps to escape from the original position by cage-breaking. The clarification of the cage-jump motion is therefore linked to unraveling the fundamental element of the slow dynamics. Here, we develop a cage-jump model for the dynamics of supercooled water. The caged and jumping states of a water molecule are introduced with respect to the hydrogen-bond (H-bond) rearrangement process, and describe the motion in supercooled states. It is then demonstrated from the molecular dynamics simulation of the TIP4P/2005 model that the characteristic length and time scales of cage-jump motions provide a good description of the self-diffusion constant that is determined in turn from the long-time behavior of the mean square displacement. Our cage-jump model thus enables to connect between H-bond dynamics and molecular diffusivity.Comment: 7 pages, 5 figures, J. Chem. Phys. for "Special Topic on Chemical Physics of Supercooled Water

Home Cage Compared with Induction Chamber for Euthanasia of Laboratory Rats

This study compared behavioral and physiologic changes in Sprague-Dawley and Brown Norway rats that were euthanizedby using a 30% volume displacement rate of CO2 in either their home cage or an induction chamber; rats euthanized in thehome cage were hypothesized to demonstrate a higher level of animal wellbeing. No significant differences were detectedin the physiologic responses to home cage versus induction chamber euthanasia groups. A few strain-related behavioraldifferences occurred. The number of digs per second was higher in Brown Norway compared with Sprague-Dawley rats when in the home cage, where a digging substrate was present. Rearing frequency was higher in both Brown Norway and Sprague-Dawley rats in the induction chamber compared with the home cage. This study demonstrated that although strainspecific differences were associated with the process of euthanasia, there were no significant differences between the treatment groups of home cage compared with induction chamber. This finding suggests that-from the perspective of a rat-either the home cage or an induction chamber can be used for euthanasia, with likely extension of this conclusion to use of either method to the induction of anesthesia

Relationship between Tibial conformation, cage size and advancement achieved in TTA procedure

Previous studies have suggested that there is a theoretical discrepancy between the cage size and the resultant tibial tuberosity advancement, with the cage size consistently providing less tibial tuberosity advancement than predicted. The purpose of this study was to test and quantify this in clinical cases. The hypothesis was that the advancement of the tibial tuberosity as measured by the widening of the proximal tibia at the tibial tuberosity level after a standard TTA, will be less than the cage sized used, with no particular cage size providing a relative smaller or higher under-advancement, and that the conformation of the proximal tibia will have an influence on the amount of advancement achieved

Bearings use dry self-lubricating cage materials

Rolling element bearings in spacecraft mechanical systems use solid lubricant composites of polytetrafluoroethylene in the bearing cage which functions as the lubricant reservoir. The cage spaces the rolling elements equally and provides the lubricant at the bearing load-carrying surface

Theoretical infra-red, Raman, and Optical spectra of the B36N36 cage

The B36N36 fullerene-like cage structure was proposed as candidate structure for the single-shell boron-nitride cages observed in electron-beam irradiation experiment. We have performed all electron density functional calculations, with large polarized Gaussian basis sets, on the B36N36 cage. We show that the cage is energetically and vibrationally stable. The infra-red, Raman and optical spectra are calculated. The predicted spectra, in combination with experimentally measured spectra, will be useful in conclusive assignment of the proposed B36N36 cage. The vertical and adiabatic ionization potentials as well as static dipole polarizability are also reported.Comment: RevTex, 4 pages, 4 figures (TO appear in Physical Review A (Breif Report)

The improved management of small-scale cage culture in Asia: final technical report

The purpose of the project is to develop sustained small-scale cage fish culture in inland and coastal waters through improved understanding of the social, institutional and resource environment of resource poor groups. Two Asian countries, Bangladesh (inland systems) and Vietnam (marine), were studied with this workshop bringing together both sides of the project together with representatives of collaborative institutions, government departments and universities. Addressing the overall aim of producing guidelines for the planning and extension of cage aquaculture in Asia a combination of group work and plenary discussion was conducted producing the following outputs. 1) An assessment of cage aquaculture potential, 2) Development options for small-scale cage culture, 3) A review of tools and methodologies and 4) Policy initiatives for sustainable cage culture development. Key issues raised were the use of outputs as a guide to be adapted to regional circumstances to facilitate farmer and extension worker discussion and not as a rigid methodology. The degree of linkage between development, research and government institutions was also considered a crucial factor in benefiting the research and development of cage culture at the local, regional and national level and vital in affecting the future policies by both development and government institutions. [PDF contains 242 pages

Sauver les médias:Capitalisme, financement participatif et démocratie

Les médias sont en crise. Pas seulement la presse écrite, mais toute la chaîne de production de l’information. Confrontés à une concurrence croissante et à une baisse inexorable des recettes publicitaires, les journaux, les radios, les télévisions, les pure players sont tous à la recherche d’un nouveau modèle. Fondé sur une étude inédite des médias en Europe et aux États-Unis, ce livre propose de créer un nouveau statut de « société de média à but non lucratif », intermédiaire entre le statut de fondation et celui de société par actions. Ce statut permettrait d’œuvrer pour des médias indépendants des actionnaires extérieurs, des annonceurs et des pouvoirs publics, mais dépendants de leurs lecteurs, de leurs salariés et des internautes. Il s’agit d’un modèle économique adapté à la révolution numérique et aux enjeux du XXIe siècle. Le débat est ouvert : il en va, tout simplement, de l’avenir de notre démocratie. Normalienne, titulaire d’un doctorat de l’université de Harvard, Julia Cagé est professeur d’économie à Sciences Po Paris. Elle est également membre de la Commission économique de la nation. (résumé éditeur

Energy-efficient motors

The use of a copper-squirrel cage in induction motors has been analyzed testing a prototype rated 1.1 kW and comparing the performances with a twin machine with an aluminum cage. The comparison has been made using torque, efficiency, starting torque, and starting current. For the considered machine size, the obtained results show that the simple substitution of the aluminum with copper can improve the efficiency of no more than 1.5% at rated load. Taking into account the copper market cost trend, the use of copper cage increases the break-even time due to the higher cost of copper rotor respect to the aluminum one. For this reason, the discussion about the use of copper cage can be still considered ope