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11.
Yannis Ioannidis Diego Milano Hans-Jörg Schek Heiko Schuldt 《International Journal on Digital Libraries》2008,9(2):101-114
DelosDLMS is a novel digital library management system (DLMS) that has been developed as an integration effort within the
DELOS Network of Excellence, a European Commission initiative funded under its fifth and sixth framework programs. In this
paper, we describe DelosDLMS that takes into account the recommendations of several activities that were initiated by DELOS
including the DELOS vision for digital libraries (DLs). A key aspect of DelosDLMS is its novel generic infrastructure that
allows the generation of digital library systems out of a set of basic system services and DL services in a modular and extensible
way. DL services like feature extraction, visualization, intelligent browsing, media-type-specific indexing, support for multilinguality,
relevance feedback and many others can easily be incorporated or replaced. A further key aspect of DelosDLMS is its robustness
against failures and its scalability for large collections and many parallel user requests. We discuss the current status
of an effort to build DelosDLMS, a Digital Library Management System that integrates in various ways several components developed
by DELOS members and showcases a great variety of functionality that is outlined as part of the DELOS vision. 相似文献
12.
Katharina N?ske Hans-Jürgen Stark Leonard Nevaril Manuel Berning Lutz Langbein Ashish Goyal Sven Diederichs Petra Boukamp 《International journal of molecular sciences》2016,17(2)
Despite decades of skin research, regulation of proliferation and homeostasis in human epidermis is still insufficiently understood. To address the role of mitoses in tissue regulation, we utilized human long-term skin equivalents and systematically assessed mitoses during early epidermal development and long-term epidermal regeneration. We now demonstrate four different orientations: (1) horizontal, i.e., parallel to the basement membrane (BM) and suggestive of symmetric divisions; (2) oblique with an angle of 45°–70°; or (3) perpendicular, suggestive of asymmetric division. In addition, we demonstrate a fourth substantial fraction of suprabasal mitoses, many of which are committed to differentiation (Keratin K10-positive). As verified also for normal human skin, this spatial mitotic organization is part of the regulatory program of human epidermal tissue homeostasis. As a potential marker for asymmetric division, we investigated for Numb and found that it was evenly spread in almost all undifferentiated keratinocytes, but indeed asymmetrically distributed in some mitoses and particularly frequent under differentiation-repressing low-calcium conditions. Numb deletion (stable knockdown by CRISPR/Cas9), however, did not affect proliferation, neither in a three-day follow up study by life cell imaging nor during a 14-day culture period, suggesting that Numb is not essential for the general control of keratinocyte division. 相似文献
13.
Hans-J. Giegerich 《Datenschutz und Datensicherheit - DuD》2016,40(5):278-282
Zahlreiche Fälle abgefischter Informationen aus E-Mails belegen, dass sensible Informationen nicht auf ?digitale Postkarten“ gehören. Viele Unternehmen und Organisationen haben dies erkannt. Bei der Einführung von E-Mail- Verschlüsselungslösungen sind jedoch unterschiedliche Anforderungen und mögliche Fallstricke zu beachten, die der folgende Beitrag überblicksartig beleuchtet. 相似文献
14.
15.
Aside from lean management and business process re-engineering, a new management approach for optimizing logistics organization is gaining recognition: supply chain management.An essential precondition to benefit from supplychain management is a structured analysis of the network-specific optimization opportunities. Opportunities are derived from suboptimal inner- and cross-organisational business processes and the related material, information and capital flows. The paper describes a supply chain analysis approach and proposes a measurement methodology integrating bottom-up and top-down performance measures as a hybrid balanced measurement approach. 相似文献
16.
Time‐dependent effects on the apparent roughness and surface free energy of different polymeric surfaces and stainless steel were studied during the biofouling process for Escherichia coli K12. The surface roughness increases during primary adhesion of E. coli on the surfaces and is later reduced as the surface between scattered bacteria is completely covered, forming a uniform biofilm. During the fouling process, the polar fraction of the surface free energy significantly increased, whereas the dispersive fraction decreased for all substrates. The attachment of E. coli and subsequent bacterial production of extracellular polymeric substances increased the polarity of the initially nonpolar polymeric surfaces to increase wettability. 相似文献
17.
The working principle of an optical isolator made of two corrugated dielectric gratings is introduced. One grating acts as a polarizer, and the other acts as a quarter-wave plate used in conical incidence converting linearly polarized light into circularly polarized light. Global maxima of diffraction efficiency for surface-corrugated gratings with binary, sinusoidal, and pyramidal ridge shapes with dependence on the material index are identified. Regarding technological feasibility for use in the visible wavelength range, high-frequency gratings with a binary shape were realized. With these gratings, an extinction ratio of more than 40 dB for the polarizer is theoretically possible, and more than 20 dB was experimentally achieved. A good correlation between theoretically calculated efficiencies and birefringences based on rigorous methods and the experimental results is demonstrated. 相似文献
18.
The onset of superconductivity due to fluctuations of the order parameter is investigated in the presence of a surface. The onset of the Meissner effect is calculated in close analogy to the Landau diamagnetism of a free-electron gas, both phenomena being due to surface currents. In the framework of the static Ginzburg-Landau theory the current density induced by a magnetic field parallel to the surface is calculated as function of the distance from the surface. It is shown that for magnetic fields above the surface-nucleation fieldH
c3 the integrated current density is the same for the two boundary conditions of vanishing order parameter and vanishing order-parameter derivative at the surface, and leads to the bulk expression for the fluctuation magnetization. Using the time-dependent Ginzburg-Landau theory, the dynamical conductivity in the surface sheath is calculated. Apart from numerical factors of order unity, the surface-sheath conductivity is found to diverge on approachingT
c3 in the same manner as the conductivity of a thin film diverges on approaching the bulk transition temperature, and is isotropic in contrast to the bulk case in the presence of a magnetic field. 相似文献
19.
Deyerl HJ Plougmann N Jensen JB Floreani F Sörensen HR Kristensen M 《Applied optics》2004,43(17):3513-3522
The polarization control method offers a flexible, robust, and low-cost route for the parallel fabrication of gratings with complex apodization profiles including several discrete phase shifts and chirp. The performance of several test gratings is evaluated in terms of their spectral response and compared with theoretical predictions. Short gratings with sidelobe-suppression levels in excess of 32 dB and transmission dips lower than 80 dB have been realized. Finally, most of the devices fabricated by the polarization control method show comparable quality to gratings manufactured by far more complex methods. 相似文献
20.
Shifts in biodegradation kinetics of the herbicides MCPP and 2,4-D at low concentrations in aerobic aquifer materials 总被引:1,自引:0,他引:1
Biodegradation kinetics of two phenoxy acid herbicides, MCPP [(+/-)-2-(4-chloro-2-methylphenoxy)propanoic acid; mecoprop] and 2,4-D [2,4-dichlorophenoxyacetic acid] were studied in laboratory batch microcosms at low concentrations (0.025-100 microg/L) using 14C technique with sediments and groundwater from a shallow aerobic sandy aquifer. Below a certain threshold concentration of approximately 1 microg/L for 2,4-D and 10 microg/L for MCPP, the biodegradation followed first-order nongrowth kinetics, and no adaptation was observed within the experimental period of 341 d. Half-lifes for ultimate degradation were 500 d for 2,4-D and 1100 d for MCPP at 10 degrees C in unpolluted aquifer sediment in this environmentally relevant concentration regime. Above the threshold concentrations, the biodegradation rate accelerated gradually due to selective growth of specific biomass, which was ascertained from 14C most probable number enumerations of specific phenoxy acid degraders. Atthe highest concentration tested (100 microg/ L), specific degraders increased from 10(-1) to 10(5) cells/g during the experiment, and half-lifes after adaptation decreased to approximately 5 d. The enhanced rate of degradation by adapted systems was maintained during degradation of the last residuals measured to less than 0.1 microg/L. In situ long-term preexposure of the aquifer sediment also resulted in significant higher degradation rates of the phenoxy acids. 相似文献