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61.
Development of an event-specific detection method for genetically modified rice Kefeng?6 by quantitative real-time PCR 总被引:1,自引:0,他引:1
Patrick Guertler Ingrid Huber Sven Pecoraro Ulrich Busch 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2012,7(1):63-70
The genetically modified (GM) rice Kefeng?6 has gained resistance against several rice pests by inserting the cpti and cry1Ac genes. As this transgenic line is not approved for import, processing and cultivation in the European Union (EU), sensitive and specific detection methods need to be available to monitor any illegal presence of Kefeng?6 in food products within the EU. The aim of this study was to develop and validate an event-specific detection method by means of quantitative real-time PCR (qPCR) for the detection of Kefeng?6 in foodstuff. A primer pair and hydrolysis probe were designed according to the right border junction sequence of the transgene. The qPCR assay was validated according to the ENGL/EURL-GMFF guidelines for GMO testing and is presented according to the MIQE guidelines. The in-house validation process resulted in a limit of detection of 5 DNA copies of the transgene with confidence intervals (95?%) between 0.07 and 0.52, a PCR efficiency of 105?% and a correlation coefficient (R 2) value of 0.9997. The specificity of the assay was tested by end-point PCR, gel electrophoresis and subsequent sequencing of the PCR products. By testing DNA of several GM and non-GM crops, cross reactivity of the assay was not observed. Further, 35 food products were analyzed for the presence of Kefeng?6 by means of the event-specific detection method. For 9 out of 35 samples, PCR products for Kefeng?6 DNA were observed. 相似文献
62.
H. W. Hahnemann Martin Müller E. Flegler H. Remus K. Jaeckel K. Haubitz L. Collatz E. W. Huber W. Encke A. Kochendörfer H. Petermöller G. Welschof 《Forschung im Ingenieurwesen》1962,28(4):130-132
Ohne Zusammenfassung
VDI 相似文献
63.
64.
Karl Huber 《Holz als Roh- und Werkstoff》1938,1(7):254-259
Ohne Zusammenfassung 相似文献
65.
K. Bach H. D. Baehr H. Bebelein A. Naumann F. W. Riegels D. Küchemann H. J. Zetzmann R. Ulken Th. Lehmann E. W. Huber E. Martyrer E. Strohbusch H. Rettig H. Meincke H. W. Hahnemann A. Steller H. Kicherer F. Frank K. Meerbeck W. Gohlke H. Weissbach J. Wotschke E. Kollmann 《Forschung im Ingenieurwesen》1963,29(5):164-168
Ohne Zusammenfassung
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66.
Jie Liu Volker Ventzke Peter Staron Norbert Schell Nikolai Kashaev Norbert Huber 《Metallurgical and Materials Transactions A》2014,45(1):16-28
Post-weld heat treatment is carried out on the laser beam welded γ-TiAl-based alloy Ti-48Al-1Cr-1.5Nb-1Mn-0.2Si-0.5B (at. pct). The macro/microstructure and mechanical properties of both as-welded and heat-treated specimens are investigated by radiography, SEM, and tensile tests. Moreover, high energy synchrotron X-ray diffraction is performed to measure the residual stresses and evaluate the microstructure evolution. It is found that the residual stresses are distributed in a three-peak shape in the region of the weld zone and heat-affected zone of the as-welded specimen due to the microstructural transformation and heat softening. The residual stresses are largely relieved after the heat treatment. The heat-treated specimens have a near fully lamellar microstructure and show balanced mechanical properties of strength and ductility. The diffraction shows that the phase transformation from α 2 to γ takes place under tensile load at 1023 K (750 °C), and the grain size and lamellar spacing are refined in the weld zone. Finally, the fracture mechanisms are found to be controlled by the local stress concentration-induced strain misfit between α 2 and γ phases in the near γ grains and delamination and debonding in the lamellae. Boride ribbons of 5 μm in the near fully lamellar microstructure are found not to be detrimental to the tensile properties. 相似文献
67.
Anna‐Lena Kjøniksen Maria Teresa Calejo Kaizheng Zhu Bo Nyström Sverre Arne Sande 《应用聚合物科学杂志》2014,131(13)
Several different polysaccharides have been added to pluronic F127 (poloxamer 407) gels to test their ability to stabilize the gels against dissolution in aqueous media over time. The studied polysaccharides include κ‐carrageenan, chitosan, hyaluronic acid, pectin, alginate, hydroxyethylcellulose, and ethyl(hydroxyethyl)cellulose. Although all the considered polysaccharides slowed down the dissolution time of the pluronic gels, unmodified polysaccharides only had a modest stabilization effect. However, hydrophobic modification of polysaccharides with a sufficiently long hydrocarbon chain (C16) was found to partly prevent the gels from dissolving for more than 6 months. Shorter hydrocarbon chains did not have the same effect, even at high degrees of hydrophobicity. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40465. 相似文献
68.
A. Nikolaeva L. Konopko T. E. Huber Gh. Para A. Tsurkan 《Surface Engineering and Applied Electrochemistry》2014,50(1):57-62
We report on the magneto-thermopower of single-crystal Bi nanowires with diameters 75 and 250 nm in a longitudinal and transverse magnetic fields of 0–14 T. The temperature range is 1.5–300 K. Bi nanowires in a glass capillary have been prepared by the high frequency liquid phase casting. The temperature dependence R(T) shows the transition from metallic to semiconducting behavior due to quantum size effect, where the Bi-wire diameter is reduced to less than 80 nm. It is for the first time that the effect of the negative magneto-resistance in a transverse magnetic field, due to the quantum size effect on 75 nm Bi wires, has been observed. The thermopower is very sensitive to the wire diameter, up to a change in the sign from negative to positive at low temperatures, and to a significant extent in a weak longitudinal magnetic field. The field dependences of longitudinal and transverse magneto-resistance have features characteristic of the occurrence of the quantum size effect and galvanomagnetic size effect, and provide information on the parameters of the energy spectrum and charge carrier mobility. The enhancement of the thermoelectric figure of merit for Bi nanowires is discussed. We also discuss the power factor α2σ and its dependence on the diameter, magnetic field and temperature. 相似文献
69.
Tim Huber Jörg Müssig Owen Curnow Shusheng Pang Simon Bickerton Mark P. Staiger 《Journal of Materials Science》2012,47(3):1171-1186
Cellulose is a fascinating biopolymer of almost inexhaustible quantity. While being a lightweight material, it shows outstanding
values of strength and stiffness when present in its native form. Unsurprisingly, cellulose fibre has been rigorously investigated
as a reinforcing component in biocomposites. In recent years, however, a new class of monocomponent composites based on cellulosic
materials, so-called all-cellulose composites (ACCs) have emerged. These new materials promise to overcome the critical problem
of fibre–matrix adhesion in biocomposites by using chemically similar or identical cellulosic materials for both matrix and
reinforcement. A number of papers scattered throughout the polymer, composites and biomolecular science literature have been
published describing non-derivatized and derivatized ACCs. Exceptional mechanical properties of ACCs have been reported that
easily exceed those of traditional biocomposites. Several different processing routes have been applied to the manufacture
of ACCs using a broad range of different solvent systems and raw materials. This article aims to provide a comprehensive review
of the background chemistry and various cellulosic sources investigated, various synthesis routes, phase transformations of
the cellulose, and mechanical, viscoelastic and optical properties of ACCs. The current difficulties and challenges of ACCs
are clearly outlined, pointing the way forward for further exploration of this interesting subcategory of biocomposites. 相似文献
70.