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221.
Edyta Janik Marcin Niemcewicz Marcin Podogrocki Michal Ceremuga Leslaw Gorniak Maksymilian Stela Michal Bijak 《Molecules (Basel, Switzerland)》2021,26(13)
Mycotoxins represent a wide range of secondary, naturally occurring and practically unavoidable fungal metabolites. They contaminate various agricultural commodities like cereals, maize, peanuts, fruits, and feed at any stage in pre- or post-harvest conditions. Consumption of mycotoxin-contaminated food and feed can cause acute or chronic toxicity in human and animals. The risk that is posed to public health have prompted the need to develop methods of analysis and detection of mycotoxins in food products. Mycotoxins wide range of structural diversity, high chemical stability, and low concentrations in tested samples require robust, effective, and comprehensible detection methods. This review summarizes current methods, such as chromatographic and immunochemical techniques, as well as novel, alternative approaches like biosensors, electronic noses, or molecularly imprinted polymers that have been successfully applied in detection and identification of various mycotoxins in food commodities. In order to highlight the significance of sampling and sample treatment in the analytical process, these steps have been comprehensively described. 相似文献
222.
We give a complex-analytic construction of the two-dimensional symbol of Parshin and Kato. Our approach leads to a new analytic formula for the symbol together with a direct proof of the reciprocity law it satisfies. 相似文献
223.
In this paper we study the maximum two-flow problem in vertex- and edge-capacitated undirected ST2-planar graphs, that is, planar graphs where the vertices of each terminal pair are on the same face. For such graphs we provide an O(n) algorithm for finding a minimum two-cut and an O(n log n) algorithm for determining a maximum two-flow and show that the value of a maximum two-flow equals the value of a minimum two-cut. We further show that the flow obtained is half-integral and provide a characterization of edge and vertex capacitated ST2-planar graphs that guarantees a maximum two-flow that is integral. By a simple variation of our maximum two-flow algorithm we then develop, for ST2-planar graphs with vertex and edge capacities, an O(n log n) algorithm for determining an integral maximum two-flow of value not less than the value of a maximum two-flow minus one. 相似文献
224.
Michal Demetrian 《International Journal of Theoretical Physics》2006,45(12):2297-2304
The second order Coleman–de Luccia instanton and its action in the Randall–Sundrum type II model are investigated and the comparison with the results in Einstein’s general relativity is done in the present paper.
PACS Numbers: 98.80.Cq. 相似文献
225.
Linear tetrahedral finite elements whose dihedral angles are all nonobtuse guarantee the validity of the discrete maximum
principle for a wide class of second order elliptic and parabolic problems. In this paper we present an algorithm which generates
nonobtuse face-to-face tetrahedral partitions that refine locally towards a given Fichera-like corner of a particular polyhedral
domain.
The first author was supported by the Swedish Foundation for Strategic Research, the second author was supported by Grant
No. 49051 of the Academy of Finland, the third author was supported by Grant No. A 1019201 of the Academy of Sciences of the
Czech Republic and by Institutional Research Plan AV0Z 10190503. 相似文献
226.
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229.
Štefan Stankovský Michal Bodajla Katarína Špirková 《Chemistry of Heterocyclic Compounds》1995,31(10):1211-1212
Department of Organic Chemistry, Slovak Technical University, 812 37 Bratislava, Slovak Republic. Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1383–1384, October, 1995. Original article submitted August 24, 1995. 相似文献
230.
Michal Feckan 《Proceedings of the American Mathematical Society》1996,124(6):1733-1742
Results on the existence of solutions are derived for asymptotically quasilinear, nonlinear operator equations. Applications are given to implicit nonlinear integral equations.