342 research outputs found

    Freie Berufe - Herausforderungen an die Wissenschaft

    Full text link
    Was sind Freie Berufe? Ihr Wesen, ihre Bedeutung fĂŒr den Menschen als Individuum und als soziales Werk? Wen oder was fordern Freie Berufe heraus, wenn sie Anforderungen an die Wissenschaft stellen? Die Fragestellungen formulieren die Konfrontation der SelbstverstĂ€ndnisse von Freien Berufen und Wissenschaftlern. Dem Wesen beider ist die Forderung nach individueller Freiheit in sozialer Verantwortung eigen. Die dynamische Vielfalt in der Wahrnehmung von Berufsbildern Freier Berufe lebt in Konfrontation zur Systematik des Panoramas der Wissenschaften. Wissenschaft ĂŒber Wesen und Bedeutung Freier Berufe muss daher stets fakultĂ€ts- und fachĂŒbergreifend in Forschung, Lehre und Praxis gelebt werden.What are liberal professions? Their essence, their importance for the person as an individual and as a social act? Who or what do libereal professions challenge if they ask for requirements for the science? The questions formulate the confrontation of the self-image of liberal professions and scientists. The demand for individual liberty in social responsibility is owned to be a liberal professional as well as a scientist. The dynamic variety in the perception of occupational pictures of liberal professions lives in confrontation to the system of the science panorama. Hence, science about the essence and meaning/importance of liberal professions must be always lived encompassing faculty overlapping research, teaching and praxis

    Freie Berufe und Mittelstand Festrede zur Verleihung der EhrendoktorwĂŒrde

    Get PDF
    This FFB-Discussion Paper documents the official speech by Professor J. F. Volrad Deneke to his award ('Doctor honoris causa') on May, 7, 1996 by the Department of Economic and Social Sciences of the University of LĂŒneburg. 'Freie Berufe und Mittelstand' ('Professions and Middle classes') is discussed by three variations. At first, social change ist treated with the industrial revolution, the service society and professions in middle classes. The economic development is the second variation which pinpoints the maximation and globalization of markets and the socialization of partial markets. Finally,public policy aspects of professions in middle classes are discussed.Professions (Freie Berufe), middle classes, social change

    Bending and wrinkling as competing relaxation pathways for strained free-hanging films

    Full text link
    An equilibrium phase diagram for the shape of compressively strained free-hanging films is developed by total strain energy minimization. For small strain gradients {\Delta}{\epsilon}, the film wrinkles, while for sufficiently large {\Delta}{\epsilon}, a phase transition from wrinkling to bending occurs. We consider competing relaxation mechanisms for free-hanging films, which have rolled up into tube structures, and we provide an upper limit for the maximum achievable number of tube rotations.Comment: 4 pages, 4 figure

    Fabrication and optical properties of strain-free self-assembled mesoscopic GaAs structures

    Get PDF
    FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESWe use a combined process of Ga-assisted deoxidation and local droplet etching to fabricate unstrained mesoscopic GaAs/AlGaAs structures exhibiting a high shape anisotropy with a length up to 1.2 mu m and a width of 150 nm. We demonstrate good controllability over size and morphology of the mesoscopic structures by tuning the growth parameters. Our growth method yields structures, which are coupled to a surrounding quantum well and present unique optical emission features. Microscopic and optical analysis of single structures allows us to demonstrate that single structure emission originates from two different confinement regions, which are spectrally separated and show sharp excitonic lines. Photoluminescence is detected up to room temperature making the structures the ideal candidates for strain-free light emitting/detecting devices.12114FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPES2012/11382-92014/17141-92015/08344-62016/14001-7475343/2013-1482729/2013-9305769/2015-4Sem informaçãoThe financial support through SisNano (MCTI Brazil), FAPESP (Processo 2012/11382-9, 2014/17141-9, 2015/08344-6 and 2016/14001-7), and CNPq (Processo 482729/2013-9, 305769/2015-4, 475343/2013-1) is acknowledged. SFCS thanks CAPES for the scholarship

    Precise control of thermal conductivity at the nanoscale through individual phonon-scattering barriers

    Get PDF
    International audienceThe ability to precisely control the thermal conductivity (Îș) of a material is fundamental in the development of on-chip heat management or energy conversion applications. Nanostructuring permits a marked reduction of Îș of single-crystalline materials, as recently demonstrated for silicon nanowires. However, silicon-based nanostructured materials with extremely low Îș are not limited to nanowires. By engineering a set of individual phonon-scattering nanodot barriers we have accurately tailored the thermal conductivity of a single-crystalline SiGe material in spatially defined regions as short as ∌15 nm. Single-barrier thermal resistances between 2 and 4×10−9 m2 K W−1 were attained, resulting in a room-temperature Îș down to about 0.9 W m−1 K−1, in multilayered structures with as little as five barriers. Such low thermal conductivity is compatible with a totally diffuse mismatch model for the barriers, and it is well below the amorphous limit. The results are in agreement with atomistic Green’s function simulations

    Contribution of Cystine-Glutamate Antiporters to the Psychotomimetic Effects of Phencyclidine

    Get PDF
    Altered glutamate signaling contributes to a myriad of neural disorders, including schizophrenia. While synaptic levels are intensely studied, nonvesicular release mechanisms, including cystine–glutamate exchange, maintain high steady-state glutamate levels in the extrasynaptic space. The existence of extrasynaptic receptors, including metabotropic group II glutamate receptors (mGluR), pose nonvesicular release mechanisms as unrecognized targets capable of contributing to pathological glutamate signaling. We tested the hypothesis that activation of cystine–glutamate antiporters using the cysteine prodrug N-acetylcysteine would blunt psychotomimetic effects in the rodent phencyclidine (PCP) model of schizophrenia. First, we demonstrate that PCP elevates extracellular glutamate in the prefrontal cortex, an effect that is blocked by N-acetylcysteine pretreatment. To determine the relevance of the above finding, we assessed social interaction and found that N-acetylcysteine reverses social withdrawal produced by repeated PCP. In a separate paradigm, acute PCP resulted in working memory deficits assessed using a discrete trial t-maze task, and this effect was also reversed by N-acetylcysteine pretreatment. The capacity of N-acetylcysteine to restore working memory was blocked by infusion of the cystine–glutamate antiporter inhibitor (S)-4-carboxyphenylglycine into the prefrontal cortex or systemic administration of the group II mGluR antagonist LY341495 indicating that the effects of N-acetylcysteine requires cystine–glutamate exchange and group II mGluR activation. Finally, protein levels from postmortem tissue obtained from schizophrenic patients revealed significant changes in the level of xCT, the active subunit for cystine–glutamate exchange, in the dorsolateral prefrontal cortex. These data advance cystine–glutamate antiporters as novel targets capable of reversing the psychotomimetic effects of PCP

    Transient Phenomena in Gene Expression after Induction of Transcription

    Get PDF
    When transcription of a gene is induced by a stimulus, the number of its mRNA molecules changes with time. Here we discuss how this time evolution depends on the shape of the mRNA lifetime distribution. Analysis of the statistical properties of this change reveals transient effects on polysomes, ribosomal profiles, and rate of protein synthesis. Our studies reveal that transient phenomena in gene expression strongly depend on the specific form of the mRNA lifetime distribution
    • 

    corecore