3,628 research outputs found

    Declining interstitial transsudation in man

    Get PDF
    Results and methodology of experimentation dealing with declining interstitial transsudation are discussed. Concepts of the formation of interstitial fluids are in agreement with measurements of calf volume in normal young women, in horizontal recumbency or after horizontal immersion. The volume of the calf is reduced when the hydrostatic pressure of the blood column is diminished under the phlebostatic level and when the external pressure is increased by the hydrostatic pressure of a water bath

    Finite size scaling of current fluctuations in the totally asymmetric exclusion process

    Full text link
    We study the fluctuations of the current J(t) of the totally asymmetric exclusion process with open boundaries. Using a density matrix renormalization group approach, we calculate the cumulant generating function of the current. This function can be interpreted as a free energy for an ensemble in which histories are weighted by exp(-sJ(t)). We show that in this ensemble the model has a first order space-time phase transition at s=0. We numerically determine the finite size scaling of the cumulant generating function near this phase transition, both in the non-equilibrium steady state and for large times.Comment: 18 pages, 11 figure

    Critical parameters for the partial coalescence of a droplet

    Full text link
    The partial coalescence of a droplet onto a planar liquid/liquid interface is investigated experimentally by tuning the viscosities of both liquids. The problem mainly depends on four dimensionless parameters: the Bond number (gravity vs. surface tension), the Ohnesorge numbers (viscosity in both fluids vs. surface tension), and the density relative difference. The ratio between the daughter droplet size and the mother droplet size is investigated as a function of these dimensionless numbers. Global quantities such as the available surface energy of the droplet has been measured during the coalescence. The capillary waves propagation and damping are studied in detail. The relation between these waves and the partial coalescence is discussed. Additional viscous mechanisms are proposed in order to explain the asymmetric role played by both viscosities.Comment: 16 pages, 14 figures, submitted to Physical Review

    On sl(2)-equivariant quantizations

    Full text link
    By computing certain cohomology of Vect(M) of smooth vector fields we prove that on 1-dimensional manifolds M there is no quantization map intertwining the action of non-projective embeddings of the Lie algebra sl(2) into the Lie algebra Vect(M). Contrariwise, for projective embeddings sl(2)-equivariant quantization exists.Comment: 09 pages, LaTeX2e, no figures; to appear in Journal of Nonlinear Mathematical Physic

    Studies on the infestation by Eutypa lata of grapevine spring wounds

    Get PDF
    Natural infestation and controlled inoculations of grapevine (mostly on the cultivar 'Cabernet Sauvignon'), were conducted in Bordeaux vineyards from 1998 to 2004 to evaluate the susceptibility to E. lata of spring wounds caused by the removal of either excess buds or excess suckers. Natural infestation was assessed across a range of sites to quantify and compare the relative risk of spring and winter pruning wounds to contamination by E. lata. Infestation caused by inoculation of wounds was examined in one site using either 100 (lower inoculum density) or 1000 (higher inoculum density) ascospores per wound. Wounds were allowed to incubate at the wound site for either two weeks or one year before isolations. For natural colonisation of wounds, a low level of infestation of spring wounds (average 2.1 %) was detected, less than those for winter pruning wounds (average 13 %). A similar trend was detected in trials involving inoculation of spring and winter pruning wounds despite infestation with identical levels of inoculum. No difference in recovery rates of E. lata was found between spring wounds caused by the removal of buds or suckers. A longer incubation period significantly increased the mean efficiency of recovery. We conclude that spring wounds may pose a significant risk to the colonisation of grapevine by the pathogen E. lata, albeit less than that of winter pruning wounds, suggesting a secondary role in the epidemiology of Eutypa dieback.

    Decomposition of symmetric tensor fields in the presence of a flat contact projective structure

    Get PDF
    Let MM be an odd-dimensional Euclidean space endowed with a contact 1-form α\alpha. We investigate the space of symmetric contravariant tensor fields on MM as a module over the Lie algebra of contact vector fields, i.e. over the Lie subalgebra made up by those vector fields that preserve the contact structure. If we consider symmetric tensor fields with coefficients in tensor densities, the vertical cotangent lift of contact form α\alpha is a contact invariant operator. We also extend the classical contact Hamiltonian to the space of symmetric density valued tensor fields. This generalized Hamiltonian operator on the symbol space is invariant with respect to the action of the projective contact algebra sp(2n+2)sp(2n+2). The preceding invariant operators lead to a decomposition of the symbol space (expect for some critical density weights), which generalizes a splitting proposed by V. Ovsienko

    Cohomology of groups of diffeomorphims related to the modules of differential operators on a smooth manifold

    Full text link
    Let MM be a manifold and TMT^*M be the cotangent bundle. We introduce a 1-cocycle on the group of diffeomorphisms of MM with values in the space of linear differential operators acting on C(TM).C^{\infty} (T^*M). When MM is the nn-dimensional sphere, SnS^n, we use this 1-cocycle to compute the first-cohomology group of the group of diffeomorphisms of SnS^n, with coefficients in the space of linear differential operators acting on contravariant tensor fields.Comment: arxiv version is already officia

    Intracellular mechanism of the action of inhibin on the secretion of follicular stimulating hormone and of luteinizing hormone induced by LH-RH in vitro

    Get PDF
    The FSH secretion-inhibiting action of inhibin in vitro under basal conditions and also in the presence of LH-RH is suppressed by the addition of MIX, a phosphodiesterase inhibitor. In the presence of LH-RH, inhibin reduces significantly the intracellular level of cAMP in isolated pituitary cells. In contrast, the simultaneous addition of MIX and inhibin raises the cAMP level, and this stimulation is comparable to the increase observed when MIX is added alone. These observations suggest that one mode of action of inhibin could be mediated by a reduction in cAMP within the pituitary gonadotropic cell

    Natural and projectively equivariant quantizations by means of Cartan Connections

    Full text link
    The existence of a natural and projectively equivariant quantization in the sense of Lecomte [20] was proved recently by M. Bordemann [4], using the framework of Thomas-Whitehead connections. We give a new proof of existence using the notion of Cartan projective connections and we obtain an explicit formula in terms of these connections. Our method yields the existence of a projectively equivariant quantization if and only if an \sl(m+1,\R)-equivariant quantization exists in the flat situation in the sense of [18], thus solving one of the problems left open by M. Bordemann.Comment: 13 page

    Graphitization in chromium cast iron

    Full text link
    peer reviewedSome trials with graphite Hi-Cr iron rolls have been done mainly in Japan, for the rolling of stainless steel. This material could lead to good compromise between oxidation, wear and thermal behaviour. By using thermal analysis and resistometry, the conditions for secondary graphite formation have been studied. The amount and volume of free graphite may be strongly increased by a suitable heat treatment, allowing a good thermal conductivity as well as high wear and mechanical properties
    corecore