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排序方式: 共有877条查询结果,搜索用时 15 毫秒
61.
Maria Smolle Stefan Uranitsch Armin Gerger Martin Pichler Johannes Haybaeck 《International journal of molecular sciences》2014,15(8):13993-14013
The latest investigations of long non-coding RNAs (lncRNAs) have revealed their important role in human cancers. LncRNAs are larger than 200 nucleotides in length and fulfill their cellular purpose without being translated into proteins. Though the molecular functions of some lncRNAs have been elucidated, there is still a high number of lncRNAs with unknown or controversial functions. In this review, we provide an overview of different lncRNAs and their role in human cancers. In particular, we emphasize their importance in tumorigenesis of colorectal cancer, the third most common cancer worldwide. 相似文献
62.
Konstantin Efimov Mirko Arnold Julia Martynczuk Armin Feldhoff 《Journal of the American Ceramic Society》2009,92(4):876-880
X-ray diffraction and transmission electron microscopy were applied to investigate a sol–gel synthetic process for the mixed oxygen ion and electron conductor La2 NiO4+δ with a K2 NiF4 structure type. The development of the La2 NiO4+δ is elucidated considering the influence of calcination temperatures and dwell times. Following the thermal decomposition of nitrate and organic precursors in an intermediate step, the lanthanum nickel oxide is obtained after a short dwell time above 750°C. This occurs by the transformation of an ultrafinely dispersed powder consisting of lanthanum oxycarbonate, lanthanum oxide, and nickel oxide. The pure La2 NiO4+δ phase was obtained by similar solid-state reactions between nanocrystalline powder particles at just 950°C. 相似文献
63.
Itzhak I. Maor Katharina Kruppa Adi Rozencweig Amir Sterzer Frank Steinbach Vadim Beilin Bernd Breidenstein Gennady E. Shter Meirav Mann-Lahav Armin Feldhoff Gideon S. Grader 《Advanced functional materials》2023,33(49):2304464
Calcium cobaltite Ca3Co4−xO9+δ (CCO) is a promising p-type thermoelectric (TE) material for high-temperature applications in air. The grains of the material exhibit strong anisotropic properties, making texturing and nanostructuring mostly favored to improve thermoelectric performance. On the one hand multitude of interfaces are needed within the bulk material to create reflecting surfaces that can lower the thermal conductivity. On the other hand, low residual porosity is needed to improve the contact between grains and raise the electrical conductivity. In this study, CCO fibers with 100% flat cross sections in a stacked, compact form are electrospun. Then the grains within the nanoribbons in the plane of the fibers are grown. Finally, the nanoribbons are electrospun into a textured ceramic that features simultaneously a high electrical conductivity of 177 S cm−1 and an immensely enhanced Seebeck coefficient of 200 µV K−1 at 1073 K are assembled. The power factor of 4.68 µW cm−1 K−2 at 1073 K in air surpasses all previous CCO TE performances of nanofiber ceramics by a factor of two. Given the relatively high power factor combined with low thermal conductivity, a relatively large figure-of-merit of 0.3 at 873 K in the air for the textured nanoribbon ceramic is obtained. 相似文献
64.
65.
In many industries mixed-model assembly systems are increasingly supplied out of third-party consignment stock. This novel
trend gives rise to a new short-term sequencing problem which decides on the succession of models launched down the line and
aims at minimizing the cost of in-process inventory held by the manufacturer. In this work, we investigate the mathematical
structure of this part oriented mixed-model sequencing problem and prove that general instances of the problem are NP-hard
in the strong sense. Moreover, we develop a new Beam Search heuristic, which clearly outperforms existing solution procedures. 相似文献
66.
Berührungslose RFID-Technologie wird weltweit für verschiedenste sicherheitsrelevante Anwendungen wie den Identit?tsnachweis
oder Bezahlvorg?nge eingesetzt. Nach der Aufdeckung von Schwachstellen im kryptografischen Schutz der „ersten Generation“
kontaktloser SmartCards hoffte man auf die mit sicheren Chiffren versehenen Nachfolger. Der Beitrag zeigt die Anf?lligkeit
kontaktloser SmartCards für Seitenkanalangriffe am Beispiel der Mifare DESFire MF3ICD40. 相似文献
67.
68.
Armin Herb 《Datenschutz und Datensicherheit - DuD》2011,35(4):270-274
Die Finanzierung des dualen Rundfunksystems in Deutschland und damit insbesondere der ?ffentlich-rechtlichen Rundfunkanstalten
soll ab dem 1. Januar 2013 auf eine neue Basis gestellt werden. Anstatt den bisherigen Gebühren für ein H?rfunk- oder Fernsehger?t
ist dann ein Rundfunkbeitrag für jede Wohnung und Betriebsst?tte zu leisten. Die nachfolgenden Ausführungen befassen sich
mit den datenschutzrechtlichen Vorschriften im neuen Rundfunkbeitragsstaatsvertrag der L?nder. 相似文献
69.
We present a mean-field approach for calculating thermodynamic properties(free energies) of protein–solvent systems. We apply this method to thetumor suppressor protein p53, where we study the stability of itstetramerization domain when subjected to site-directed mutagenesis. Acomparison with experimental results is included. 相似文献
70.
Analytic models based on discrete-time Markov chains (DTMC) are proposed to assess the algorithmic performance of Software Transactional Memory (TM) systems. Base STM variants are compared: optimistic STM with inplace memory updates and write buffering and pessimistic STM. Starting from an absorbing DTMC, closed-form analytic expressions are developed, which are quickly solved iteratively to determine key parameters of the considered STM systems, like the mean number of transaction restarts and the mean transaction length. Since the models reflect complex transactional behavior in terms of read/write locking, data consistency checks and conflict management independent of implementation details, they highlight the algorithmic performance advantages of one system over the other, which – due to their at times small differences – are often blurred by implementation of STM systems and even difficult to discern with statistically significant discrete-event simulations. 相似文献