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The development and cultivation of genetically modified crops is still increasing globally. Food and feed imports from outside the European Union (EU) will subsequently require more effort from the responsible authorities in monitoring the compliance with effective labelling regulations. The aim of this study was the development of the GMOfinder, a database for collection and interpretation of information related to the screening for genetically modified organisms (GMOs). Different genetic elements (e.g. promoters, terminators, structural genes) are artificially introduced into plants to establish new genetic modifications. The introduced elements may vary between GMO events, depending on the intended trait(s). Screening for such inserted elements with (real-time) polymerase chain reaction is a common first step to analyse samples for the presence of any genetical modification. From the pattern of detectable and nondetectable elements, valuable conclusions about the identity of putative present GMO event(s) can be drawn with the GMOfinder. Information about selected genetic elements from the literature, applications for authorisation and other (web) sources were systematically integrated in a tabular matrix format. Special care was taken to additionally record the sources of the information, thus facilitating evaluation of screening results, and tracing of possible errors in the matrix. The GMOfinder accesses data from the element matrix with implemented algorithms and facilitates to interpret the outcome of screenings. Such a preselection helps to systematically narrow down the candidates for subsequent identification reactions. Optional display of events with potentially masked elements completes the included features. 相似文献
103.
The objective of this paper is to provide a theoretical foundation for program extraction from inductive and coinductive proofs geared to practical applications. The novelties consist in the addition of inductive and coinductive definitions to a realizability interpretation for first-order proofs, a soundness proof for this system, and applications to the synthesis of non-trivial provably correct programs in the area of exact real number computation. We show that realizers, although per se untyped, can be assigned polymorphic recursive types and hence represent valid programs in a lazy functional programming language such as Haskell. Programs extracted from proofs using coinduction can be understood as perpetual processes producing infinite streams of data. Typical applications of such processes are computations in exact real arithmetic. As an example we show how to extract a program computing the average of two real numbers w.r.t. the binary signed digit representation. 相似文献
104.
Antje Grünewald-LükeHermann Gies Ulrich MüllerBilge Yilmaz H. ImaiTakashi Tatsumi B. XieFeng-Shou Xiao Xinhe BaoWeiping Zhang Dirk De Vos 《Microporous and mesoporous materials》2012,147(1):102-109
Condensation of layered silicate precursors leads to new, all silica zeolite frameworks. In order to introduce catalytic functionality, boron has been substituted into the silicate layer of RUB-39 in a single step synthesis process. Condensation of the silicate layer to the zeolite framework of RUB-41, RRO framework structure type, preserved B as constituent of the material. Analysis of structural details obtained from Rietveld analysis of powder diffraction data, 11B and 29Si NMR experiments of the as synthesized precursor as well as of the zeolite condensation product, and crystal chemical reasoning indicates segregation of B on one specific T-site. This T-site is buried in the silicate anionic layer of the precursor shielding the additional negative charge introduced by the trivalent T-atom. 相似文献
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Highly resistive dusts show markedly non‐ohmic properties. The property known as specific resistivity is strongly dependent on the dust layer thickness and on the polarity of the high voltage. The current transport occurs by excess charges of both polarities, which leads to high space charge densities and induces strong electrostatic fields. The theory of electrets provides a consistent explanation of the phenomena observed so far. To investigate the electrical properties, highly resistive dusts were exposed to an electrical field with interfering corona discharges within a tip‐plate arrangement. 相似文献
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Lena Arnold Gauthier Averlant Dr. Stefan Marx Mathias Weickert Ulrich Müller Jonathan Mertel Carsten Horch Mikulas Peksa Frank Stallmach 《化学,工程师,技术》2013,85(11):1726-1733
With the increasing demand for alternative fuels the storage of natural gas (NG) in adsorbents like metal organic frameworks (MOFs) will become more important. In order to use MOFs as storage media in fuel delivery systems, the optimization of mass and energy transfer of the system is crucial. For rapid NG filling of a tank, molecules need to reach the adsorption sites within a reasonable time while the heat of adsorption should be dissipated to the environment. In this article, mass transfer in shaped bodies of MOFs was determined by permeability measurements and pulsed field gradient (PFG) NMR spectroscopy. The heat dissipation was also experimentally measured and both data sets were used to set up a theoretical density function theory model to predict the behavior of MOFs for NG storage. 相似文献
110.