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91.
Accreditation of GMO detection laboratories: Improving the reliability of GMO detection 总被引:4,自引:0,他引:4
Jana Žel Katarina Cankar Maja Ravnikar Marjana Camloh Kristina Gruden 《Accreditation and quality assurance》2006,10(10):531-536
Reliable and efficient methods for detecting genetically modified organisms (GMOs) are essential for establishing an effective system for traceability all along the supply chain from seed producers to final consumers. The latter is especially meaningful in European Union and other countries where strict legislations on GMOs were set up. Performance of the methods used in laboratories around the world should be uniform, in order to obtain reliable and comparable results. Accreditation is a suitable system for harmonising procedures in each testing laboratory. In this paper, key elements for the accreditation of molecular biology methods for GMO detection according to ISO/IEC 17025 are described. The procedures described are also valuable for the accreditation of molecular methods for all laboratory diagnostics where qualitative and quantitative characterisation of nucleic acids is needed. 相似文献
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Milica Milošević Marija Radoičić Zoran Šaponjić Tim Nunney Christopher Deeks Vesna Lazić Miodrag Mitrić Tamara Radetić Maja Radetić 《Cellulose (London, England)》2014,21(5):3781-3795
The possibility of in situ photoreduction of Ag+-ions using TiO2 nanoparticles deposited on cotton and cotton/PET fabrics in the presence of amino acid alanine and methyl alcohol has been discussed. The possible interaction between TiO2, alanine and Ag+-ions was evaluated by FTIR analysis. The fabrication of TiO2/Ag nanoparticles on both fabrics was confirmed by SEM, EDX, XRD, XPS and AAS analyses. Cotton and cotton/PET fabrics impregnated with TiO2/Ag nanoparticles provided maximum reduction of Gram-negative bacteria Escherichia coli and Gram-positive bacteria Staphylococcus aureus. Although excellent antibacterial activity was preserved after ten washing cycles, a significant amount of silver leached out from the fabrics into the washing bath. The perspiration fastness assessment revealed that smaller amounts of silver were also released from the fabrics into artificial sweat at pH 5.50 and 8.00. In addition, deposited TiO2/Ag nanoparticles imparted maximum UV protection to fabrics. 相似文献
94.
Gruden-Pavlović M García-Fernández P Andjelković L Daul C Zlatar M 《The journal of physical chemistry. A》2011,115(39):10801-10813
The family of the Jahn-Teller (JT) active hydrocarbon rings, C(n)H(n) (n = 5-7), was analyzed by the means of multideterminantal density functional theory (DFT) approach. The multimode problem was addressed using the intrinsic distortion path (IDP) method, in which the JT distortion is expressed as a linear combination of all totally symmetric normal modes in the low symmetry minimum energy conformation. Partitioning of the stabilization energy into the various physically meaningful terms arising from Kohn-Sham DFT has been performed to get further chemical insight into the coupling of the nuclear movements and the electron distribution. 相似文献
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Dragana . Dabi Zagorac Milica M. Fotiri Aki Vesna Glavnik Uro M. Gai Irena Vovk
ivoslav Lj. Tei Maja M. Nati 《Journal of separation science》2020,43(8):1431-1439
The profile of flavan‐3‐ols and proanthocyanidins in five different Rosa species (R. canina, R. glutinosa, R. rubiginosa, R. multiflora, and R. spinosissima) was estimated on high performance thin layer chromatography cellulose plates. Differences in flavanol and proanthocyanidin profiles of the extracts were evident, among which Rosa spinosissima stood out with catechin as the only detected flavanol and red zones as indication of anthocyanins. Furthermore, the elution solvent for thin layer chromatography with mass spectrometry analyses of glycosylated flavan‐3‐ols and proanthocyanidins was optimized, enabling identification of catechin, (epi)catechin hexoside, proanthocyanidin dimer, and proanthocyanidin dimers and trimers hexosides. A total of 15 flavanols and their derivatives were identified using ultra‐high‐performance liquid chromatography with linear trap quadrupole‐Orbitrap mass analyzer and epicatechin, gallocatechin, and proanthocyanidin trimer were identified only using this technique. However, proanthocyanidin trimer trihexoside was identified only by thin‐layer chromatography with mass spectrometry. To establish the relationships between the flavanols and proanthocyanidins composition of rose hip and their origin, principal component analysis was performed on the entire set of liquid chromatography/mass spectrometry data. Both principal components’ scores plots showed that Rosa spinosissima could be considered as an outlier. Our study demonstrated that flavanol and proanthocyanidin profiles of different rose hips depend on the geographical origin rather than on the cultivar and genotype. 相似文献
97.
Stanisavljev DR Milenković MC Mojović MD Popović-Bijelić AD 《The journal of physical chemistry. A》2011,115(27):7955-7958
The existence of free radicals in iodine-based oscillatory systems has been debated for some time. Recently, we have reported the presence of reactive oxygen species (ROS) in the iodide-peroxide system in acidic medium, which is common to all iodine--based oscillatory systems ( J. Phys. Chem. A 2011 , 115 , 2247--2249 ). In this work, the goal was to identify the ROS produced in this system using an EPR spin trap which can distinguish between hydroxyl (HO(?)) and hydroperoxyl (HOO(?)) radicals. The formation of the hydroperoxyl radical was observed and a possible explanation for the low EPR signal of hydroxyl radical was proposed. 相似文献
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99.
Structural Chemistry - This paper was written on the occasion of the 30th special Jubilee volume of Structural Chemistry journal in 2019. It offered us a unique opportunity to look at our common... 相似文献
100.
The contents of issues 5 and 6 of Structural Chemistry from the calendar year 2017 are summarized in the present review. A brief thermochemical commentary and recommendations for future research have been added to the summary of each paper.
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