21,115 research outputs found

    Ecological study of aquatic midges and some related insects with special reference to feeding habits

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    Die Schweiz ist ein reiches Land. Sie verfügt über viele Millionäre. Der große Reichtum konzentriert sich auf wenige Familien und Personen. In der Schweiz leben aber auch eine halbe Million der Bevölkerung (7,5 Mio.) in Haushalten von Erwerbstätigen, die weniger als das Existenzminimum verdienen. Über 200‘000 Personen sind auf Sozialhilfe angewiesen. Bei den Vermögen und den verfügbaren Einkommen hat sich in den letzten Jahren die Kluft zwischen den obersten und untersten zehn Prozent verschärft. Die Zunahme der sozialen Ungleichheit erhöht die soziale Brisanz, was mehr zu ergründen ist. Die soziale Differenzierung dokumentiert Prozesse der Globalisierung. Sie reproduziert und spezifiziert alte soziale Ungleichheiten. Wichtig ist, dass die Soziale Arbeit das thematisiert und weiter theoretisiert

    Molecular Identification of Lactic Acid Bacteria Occurring in Must and Wine

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    A specifically amplified polymorphic DNA-polymerase chain reaction (SAPD-PCR), a molecularfingerprinting method based on the amplification of specific gene sequences, was applied in order to allowa rapid identification of lactic acid bacteria (LAB) occurring in must and wine. The applicability of thismethod was confirmed with isolated strains from different wine samples from the German wine growingregion Palatinate. In addition, the formation of biogenic amines by the isolated strains was studied. Morethan half of the bacterial isolates from 50 red and white wine samples were able to produce biogenic amines.General health concerns related to biogenic amines in must and wine underline the need for an identificationof these species. The majority of the isolated strains were assigned to the species Lactobacillus brevis. Themajor biogenic amines in the investigated wines which were detected by thin-layer chromatography andHPLC were tyramine, histamine and ethylamine

    Optimization of Short Coherent Control Pulses

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    The coherent control of small quantum system is considered. For a two-level system coupled to an arbitrary bath we consider a pulse of finite duration. We derive the leading and the next-leading order corrections to the evolution operator due to the non-commutation of the pulse and the bath Hamiltonian. The conditions are computed that make the leading corrections vanish. The pulse shapes optimized in this way are given for π\pi and π2\frac{\pi}{2} pulses.Comment: 9 pages, 6 figures; published versio

    Condensate fragmentation as a sensitive measure of the quantum many-body behavior of bosons with long-range interactions

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    The occupation of more than one single-particle state and hence the emergence of fragmentation is a many-body phenomenon universal to systems of spatially confined interacting bosons. In the present study, we investigate the effect of the range of the interparticle interactions on the fragmentation degree of one- and two-dimensional systems. We solve the full many-body Schr\"odinger equation of the system using the recursive implementation of the multiconfigurational time-dependent Hartree for bosons method, R-MCTDHB. The dependence of the degree of fragmentation on dimensionality, particle number, areal or line density and interaction strength is assessed. It is found that for contact interactions, the fragmentation is essentially density independent in two dimensions. However, fragmentation increasingly depends on density the more long-ranged the interactions become. The degree of fragmentation is increasing, keeping the particle number NN fixed, when the density is decreasing as expected in one spatial dimension. We demonstrate that this remains, nontrivially, true also for long-range interactions in two spatial dimensions. We, finally, find that within our fully self-consistent approach, the fragmentation degree, to a good approximation, decreases universally as N1/2N^{-1/2} when only NN is varied.Comment: 8 pages of RevTex4-1, 5 figure

    Renormalization flow of Yang-Mills propagators

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    We study Landau-gauge Yang-Mills theory by means of a nonperturbative vertex expansion of the quantum effective action. Using an exact renormalization group equation, we compute the fully dressed gluon and ghost propagators to lowest nontrivial order in the vertex expansion. In the mid-momentum regime, p2O(1)GeV2p^2\sim\mathcal{O}(1)\text{GeV}^2, we probe the propagator flow with various {\em ans\"atze} for the three- and four-point correlations. We analyze the potential of these truncation schemes to generate a nonperturbative scale. We find universal infrared behavior of the propagators, if the gluon dressing function has developed a mass-like structure at mid-momentum. The resulting power laws in the infrared support the Kugo-Ojima confinement scenario.Comment: 28 pages, 5 figures. V2: Typos corrected and reference adde

    Low Space External Memory Construction of the Succinct Permuted Longest Common Prefix Array

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    The longest common prefix (LCP) array is a versatile auxiliary data structure in indexed string matching. It can be used to speed up searching using the suffix array (SA) and provides an implicit representation of the topology of an underlying suffix tree. The LCP array of a string of length nn can be represented as an array of length nn words, or, in the presence of the SA, as a bit vector of 2n2n bits plus asymptotically negligible support data structures. External memory construction algorithms for the LCP array have been proposed, but those proposed so far have a space requirement of O(n)O(n) words (i.e. O(nlogn)O(n \log n) bits) in external memory. This space requirement is in some practical cases prohibitively expensive. We present an external memory algorithm for constructing the 2n2n bit version of the LCP array which uses O(nlogσ)O(n \log \sigma) bits of additional space in external memory when given a (compressed) BWT with alphabet size σ\sigma and a sampled inverse suffix array at sampling rate O(logn)O(\log n). This is often a significant space gain in practice where σ\sigma is usually much smaller than nn or even constant. We also consider the case of computing succinct LCP arrays for circular strings
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