3,261 research outputs found

    The eDAL Suite: Tools and Concepts for Primary Data Citation

    Get PDF
    Retrieval and citation of primary data is the important factor in the approaching age of “data science”. Digital data are easily shared, and just as easily wiped or lost. The problem of keeping on-line data accessible and
retrievable is especially difficult for SME like plant breeders plant biotech companies as well as research projects in this domain.
Intension of eDAL is the provisioning of an information retrieval and data citation infrastructure that meets the requirements of the “data science” age and implements a re-usable platform for data retrieval, data
citation, and data publication. Like a shopping cart, the idea is to combine a search engine and a data cart, which retrieves, rank and collect query relevant data from crop plant data centers

    Theory of Charmless Inclusive B Decays and the Extraction of V_{ub}

    Full text link
    We present ``state-of-the-art'' theoretical expressions for the triple differential B->X_u l^- nu decay rate and for the B->X_s gamma photon spectrum, which incorporate all known contributions and smoothly interpolate between the ``shape-function region'' of large hadronic energy and small invariant mass, and the ``OPE region'' in which all hadronic kinematical variables scale with M_B. The differential rates are given in a form which has no explicit reference to the mass of the b quark, avoiding the associated uncertainties. Dependence on m_b enters indirectly through the properties of the leading shape function, which can be determined by fitting the B->X_s gamma photon spectrum. This eliminates the dominant theoretical uncertainties from predictions for B->X_u l^- nu decay distributions, allowing for a precise determination of |V_{ub}|. In the shape-function region, short-distance and long-distance contributions are factorized at next-to-leading order in renormalization-group improved perturbation theory. Higher-order power corrections include effects from subleading shape functions where they are known. When integrated over sufficiently large portions in phase space, our results reduce to standard OPE expressions up to yet unknown O(alpha_s^2) terms. Predictions are presented for partial B->X_u l^- nu decay rates with various experimental cuts. An elaborate error analysis is performed that contains all significant theoretical uncertainties, including weak annihilation effects. We suggest that the latter can be eliminated by imposing a cut on high lepton invariant mass.Comment: 45 pages, 4 figures; several minor revisions, more systematic treatment of subleading shape-function effects, numerical results and tables updated; version to appear in Physical Review

    The LAILAPS Search Engine: A Feature Model for Relevance Ranking in Life Science Databases

    Get PDF
    Efficient and effective information retrieval in life sciences is one of the most pressing challenge in bioinformatics. The incredible growth of life science databases to a vast network of interconnected information systems is to the same extent a big challenge and a great chance for life science research. The knowledge found in the Web, in particular in life-science databases, are a valuable major resource. In order to bring it to the scientist desktop, it is essential to have well performing search engines. Thereby, not the response time nor the number of results is important. The most crucial factor for millions of query results is the relevance ranking. In this paper, we present a feature model for relevance ranking in life science databases and its implementation in the LAILAPS search engine. Motivated by the observation of user behavior during their inspection of search engine result, we condensed a set of 9 relevance discriminating features. These features are intuitively used by scientists, who briefly screen database entries for potential relevance. The features are both sufficient to estimate the potential relevance, and efficiently quantifiable. The derivation of a relevance prediction function that computes the relevance from this features constitutes a regression problem. To solve this problem, we used artificial neural networks that have been trained with a reference set of relevant database entries for 19 protein queries. Supporting a flexible text index and a simple data import format, this concepts are implemented in the LAILAPS search engine. It can easily be used both as search engine for comprehensive integrated life science databases and for small in-house project databases. LAILAPS is publicly available for SWISSPROT data at http://lailaps.ipk-gatersleben.d

    Stand und Perspektiven der landwirtschaftlichen Bewirtschaftung von Dauergrünland im norddeutschen Küstenraum

    Get PDF
    Der vorliegende Beitrag beleuchtet die derzeitige Situation der landwirtschaftlichen Betriebe, die in den Dauergrünlandgebieten des norddeutschen Küstenraumes wirtschaften. Von großer Bedeutung ist aktuell die Milchviehhaltung und Jungrinderaufzucht. Es wird aufgezeigt, dass die Bewirtschaftung dieser Grünlandstandorte auch unter den geänderten Produktionsbedingungen der Europäischen Union eine Zukunft hat. Dies wiederum eröffnet auch Möglichkeiten für den Schutz von Wiesenvögeln durch ein gemeinsames Handeln von Landwirten und Naturschützern.The present study deals with the current situation of farmers in the coastal grassland areas of Lower Saxony. Actually, the agricultural practice is dominated by dairy farming and the fattening of steers for beef production. It is shown that sustainable farming in coastal grasslands even under the new conditions of the European CAP-reform is possible. This again presents options for the protection of meadow birds by designing effective management strategies in close cooperation between farmers and nature conservationists

    Android Security, Pitfalls, Lessons Learned and BYOD

    Get PDF
    Over the last two years Android became the most popular mobile operating system. But Android is also targeted by an over-proportional share of malware. In this paper we systematize the knowledge about the Android security mechanisms and formulate how the pitfalls can be avoided when building a mobile operating system. As smartphones enter the corporate domain, a new scheme called bring your own device (BYOD) became popular. One solution is to logically partition the device such that personal and business information are isolated from one another. We systematize the solutions for partitioning in Android

    Stoichiometry determination of chalcogenide superlattices by means of X-ray diffraction and its limits

    Full text link
    In this paper we explore the potential of stoichiometry determination for chalcogenide superlattices, promising candidates for next-generation phase-change memory, via X-ray diffraction. To this end, a set of epitaxial GeTe/Sb2Te3 superlattice samples with varying layer thicknesses is sputter-deposited. Kinematical scattering theory is employed to link the average composition with the diffraction features. The observed lattice constants of the superlattice reference unit cell follow Vegard's law, enabling a straight-forward and non-destructive stoichiometry determination.Comment: physica status solidi (RRL) - Rapid Research Letters (2019

    A two-loop relation between inclusive radiative and semileptonic B-decay spectra

    Full text link
    A shape-function independent relation is derived between the partial B->X_u+l+nu decay rate with a cut on P_+=E_X-P_X<Delta and a weighted integral over the normalized B->X_s+gamma photon-energy spectrum. The leading-power contribution to the weight function is calculated at next-to-next-to-leading order in renormalization-group improved perturbation theory, including exact two-loop matching corrections at the scale mu_i^2 ~ m_b*Lambda_{QCD}. The overall normalization of the weight function is obtained up to yet unknown corrections of order [alpha_s(m_b)]^2. Power corrections from phase-space factors are included exactly, while the remaining subleading contributions are included at first order in 1/m_b. At this level unavoidable hadronic uncertainties enter, which are estimated in a conservative way. The combined theoretical accuracy in the extraction of |V_{ub}| is at the level of 5% if a value of Delta near the charm threshold can be achieved experimentally.Comment: 22 pages, 4 figures; few comments and one reference added; version to appear in JHE
    corecore