3,135 research outputs found

    Profile of public laboratories, industrial partnerships and organisation of R & D: the dynamics of industrial relationships in a large research organisation

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    There is a paucity of papers dealing with the system characteristics of laboratories or, put in another way, the institutional character of research organisations. Neither R & D economics nor the sociology of science, as traditionally conceived, has made much headway in providing insight into sets of R & D laboratories and their evolution. Drawing upon an empirical study in the plant breeding and biochemical industry, this paper presents a typology of public research laboratories which is based on three dimensions: scientific production and visibility, type of funding (public or private) and homogeneity of research themes. Three types of public laboratory emerge: the first, called “research centres for the profession”, is composed essentially of laboratories with close ties with small and medium firms (SMEs) and industry associations. The second, called “designers of generic tools and methods”, is oriented towards basic research and themes of general interest to the industry as a whole. The third type, called “basic and specialised laboratories”, strives to develop its scientific visibility. Contracts between this type of laboratory and industry are mainly bilateral and demonstrate the complementarity between public and private research. Each type of laboratory develops specific types of relationship with private partners. The authors have identified three logics underlying these relationships: proximity, market and club. The main objective of contracts based on a proximity logic is to test a hypothesis, while the knowledge produced is mostly tacit and specific. By contrast, knowledge is entirely coded and specific in the market logic, where the aim of the contract is to implement expertise in order to relieve a scientific bottleneck. In a club logic, the aim of contracts is to produce a technical referent. In each kind of contract, the learning trajectories, modes of co-ordination, role of trust and degree to which contracts are complete or not, are different.

    Re-discovery of Mesogloea brasiliensis Montagne

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    No presente trabalho o autor refere o achado de uma planta coletada uma única vez no litoral sul do Brasil. Além de uma nova descrição é também proposta uma nova combinação em conformidade com a moderna nomenclatura ficológica

    The reproduction of Ochtodes secundiramea (montagne) howe (Gigartinales, Rhizophyllidaceae)

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    Este trabalho apresenta, pela primeira vez, detalhes de organização do ramo carpogonial de um dos representantes das Rhizophyllidaceae, estrutura essa desconhecida nessa família, bem como detalhes de organização dos ramos de células auxiliares da fecundação e ainda pormenores do desenvolvimento dos espermatângios. Os estudos foram feitos em Ochtodes secundiramea (Mont.) Howe. Deste gênero também são apresentados pela primeira vez os tetrasporângios. Estas estruturas são similares às conhecidas nos gêneros Rhizophyllis e Desmia, os outros dois gêneros da família. Certos detalhes importantes da organização vegetativa são também apresentados. Esta é a primeira referência do gênero e espécie no Atlântico Sul Ocidental.This paper gives informations on the type of carpogonial branches found in a representative of the family Rhizophyllidaceae, as well as details of the auxiliary cell branches in the genus Ochtodes. Details of the development of the spermatangia in this genus are also presented. The tetrasporic plants, not yet known in this genus are described for the first time. The tetrasporangia are produced in nemathecia and have no sterile filaments in between, and in this respect are similar to the ones found in Rhizophyllis and Desmia the only other two genera of the family. Details of certain peculiarities of the vegetative thallus are also given. This is the first report of Ochtodes secundiramea in the American Western South Atlantic

    Inelastic X-ray scattering from valence electrons near absorption edges of FeTe and TiSe2_2

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    We study resonant inelastic x-ray scattering (RIXS) peaks corresponding to low energy particle-hole excited states of metallic FeTe and semi-metallic TiSe2_2 for photon incident energy tuned near the L3L_{3} absorption edge of Fe and Ti respectively. We show that the cross section amplitudes are well described within a renormalization group theory where the effect of the core electrons is captured by effective dielectric functions expressed in terms of the the atomic scattering parameters f1f_1 of Fe and Ti. This method can be used to extract the dynamical structure factor from experimental RIXS spectra in metallic systems.Comment: 6 pages, 4 figure

    Explaining the x-ray nonlinear susceptibility of diamond and silicon near absorption edges

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    International audienceWe report the observation and the theoretical explanation of the parametric down-conversion nonlinear susceptibility at the K-absorption edge of diamond and at the L 23-absorption edge of a silicon crystal. Using arguments similar to those invoked to successfully predict resonant inelastic x-ray spectra, we derive an expression for the renormalization term of the nonlinear susceptibility at the x-ray edges, which can be evaluated by using first-principles calculations of the atomic scattering factor f 1. Our model is shown to reproduce the observed enhancement of the parametric down-conversion at the diamond K and the Si L 23 edges rather than the suppression previously claimed

    Exponential decay for the damped wave equation in unbounded domains

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    We study the decay of the semigroup generated by the damped wave equation in an unbounded domain. We first prove under the natural geometric control condition the exponential decay of the semigroup. Then we prove under a weaker condition the logarithmic decay of the solutions (assuming that the initial data are smoother). As corollaries, we obtain several extensions of previous results of stabilisation and control

    Sequence of a putative Vitis vinifera PR-1

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    Research Note
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