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71.
M.H. Lim 《Linear and Multilinear Algebra》2013,61(3):231-234
In this note we give a simple proof and an extension of a dimension inequality of Howard concerning the range of a multilinear function with vector space range by using some results on algebraic varieties. 相似文献
72.
《代数通讯》2013,41(9):3061-3080
ABSTRACT Using an explicit resolution of the diagonal for the variety V 5, we provide cohomological characterizations of the universal and quotient bundles. A splitting criterion for bundles over V 5 is also proved. The presentation of semistable aCM bundles is shown, together with a resolution–theoretic classification of low rank aCM bundles. 相似文献
73.
Norman R. Reilly 《代数通讯》2013,41(11):3624-3659
We study the lattice ?(RSn) of subvarieties of the variety of semigroups generated by completely 0-simple semigroups over groups with exponent dividing n, with a particular focus on the lattice ??(RSn) consisting of those varieties that are generated by completely 0-simple semigroups. The sublattice of ??(RSn) consisting of the aperiodic varieties is described and several endomorphisms of ?(RSn) considered. The complete congruence on ??(RSn) that relates varieties containing the same aperiodic completely 0-simple semigroups is considered in some detail. 相似文献
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Olha Мykhailenko Sergiy Chetvernya Ivan Bezruk Yrii Buydin Nadija Dhurenko Olena Рalamarchuk Liudas Ivanauskas Victoriya Georgiyants 《Biomedical chromatography : BMC》2022,36(7):e5369
Iris genus plants are a valuable source of bioactive compounds, which are an important component for pharmaceutical development. The present article shows the potential for mineral nutrition with application of magnesium sulfate, iron chelates and potassium oxide affecting the phenolic compound contents in Iris hybrida ‘Tsikavynka’, I. hybrida ‘Tambo’ and I. hybridа ‘Widecombe Fire’. The effect of mineral processing was specific to plant organs and varied in the component composition. The Iris rhizomes had an increased total phenolic compound content after treatment (up to 10% of the total isoflavonoid content, up to 8% of phenolic acids, up to 5% of γ-pyrones and up to 13% of flavonoids), determined using UV–vis spectroscopy. A positive effect of nutrition on the biosynthesis and content of individual isoflavonoids (tectoridin, nigricin d -glucoside, genistin, iristectorigenin B, nigricin, irigenin and irisolidone) and xanthone mangiferin in Iris rhizomes by HPLC was established. In addition, an increase in the chlorogenic acid amount in Iris leaves was noted. The results demonstrate the sensitivity of Iris phenylpropanoid metabolism to mineral nutrition and can be used to predict medical plant cultivation with increased content of bioactive constituents. 相似文献
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《Discrete Mathematics》2020,343(9):111965
We determine the number of -rational points of hyperplane sections of classical determinantal varieties defined by the vanishing of minors of a fixed size of a generic matrix, and identify the hyperplane sections giving the maximum number of -rational points. Further we consider similar questions for sections by linear subvarieties of a fixed codimension in the ambient projective space. This is closely related to the study of linear codes associated to determinantal varieties, and the determination of their weight distribution, minimum distance, and generalized Hamming weights. The previously known results about these are generalized and expanded significantly. Connections to eigenvalues of certain association schemes, distance regular graphs, and rank metric codes are also indicated. 相似文献