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101.
Kobayashi T Nakanishi H Nishizawa NK 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2010,86(9):900-913
Higher plants utilize various mechanisms to maintain iron homeostasis. To acquire sparingly soluble iron from the rhizosphere, graminaceous plants synthesize natural iron (III) chelators known as mugineic acid family phytosiderophores (MAs). Recent research has uncovered various genes involved in iron uptake and translocation, as well as factors regulating the expression of these genes, especially in rice. Manipulation of these molecular components is used to produce transgenic crops with enhanced tolerance to iron deficiency, or with a high seed iron content. Since iron homeostasis is closely linked to that of other mineral elements, an understanding of this phenomenon will serve as the basis for the production of crops with low concentrations of toxic metals and transgenic plants for phytoremediation. 相似文献
102.
In this paper, we use character-theoretic techniques to give new nonexistence results for -strong external difference families (SEDFs). We also use cyclotomic classes to give two new classes of SEDFs with . 相似文献
103.
《Journal of Graph Theory》2018,89(1):26-39
The Turán number of a graph H, , is the maximum number of edges in any graph of order n that does not contain an H as a subgraph. A graph on vertices consisting of k triangles that intersect in exactly one common vertex is called a k‐fan, and a graph consisting of k cycles that intersect in exactly one common vertex is called a k‐flower. In this article, we determine the Turán number of any k‐flower containing at least one odd cycle and characterize all extremal graphs provided n is sufficiently large. Erdős, Füredi, Gould, and Gunderson determined the Turán number for the k‐fan. Our result is a generalization of their result. The addition aim of this article is to draw attention to a powerful tool, the so‐called progressive induction lemma of Simonovits. 相似文献
104.
105.
A. Avilés 《Journal of Functional Analysis》2010,259(11):2776-2792
Di Piazza and Preiss asked whether every Pettis integrable function defined on [0,1] and taking values in a weakly compactly generated Banach space is McShane integrable. In this paper we answer this question in the negative. Moreover, we give a counterexample where the target Banach space is reflexive. 相似文献
106.
In this paper, several recursive constructions for directed difference family and perfect directed difference family are presented by means of difference matrix and incomplete difference matrix. Finally the necessary and sufficient conditions for the existence of a (gv, g, 3, λ)-directed difference family in Zgv are established. As a consequence, the necessary and sufficient conditions for the existence of a cyclic directed group divisible design with block size three and type gv are obtained. 相似文献
107.
Ramesh C. Gupta 《Applied mathematics and computation》2010,216(4):1267-3087
The purpose of this paper is to investigate a very useful application of a certain local dependence function γf(x,y), which was considered recently by Holland and Wang [20]. An interesting property of γf(x,y) is that the underlying joint density f(x,y) is TP2 (that is, totally positive of order 2) if and only if . This gives an elegant way to investigate the TP2 property of any bivariate distribution. For the Saramanov family, the Ali-Mikhail-Haq family of bivariate distributions and the family of bivariate elliptical distributions, we derive the local dependence function and obtain conditions for f(x,y) to be TP2. These families are quite rich and include many other large classes of bivariate distributions as their special cases. Similar conditions are obtained for bivariate distributions with exponential conditionals and bivariate distributions with Pareto conditionals. 相似文献
108.
S.Z. Németh 《Applied mathematics and computation》2010,217(5):2184-2190
The notion of exceptional family of elements for general order complementarity problems in Banach spaces will be introduced. It will be shown that for general order complementarity problems defined by completely continuous fields the problem has either a solution or an exceptional family of elements. Finite dimensional examples and an application to integral operators will be given. 相似文献
109.
In this article we investigate the existence of solutions on a compact interval for the fractional integro-differential inclusions with state-dependent delay in Banach spaces when the delay is infinite. We consider the cases when the multivalued nonlinear term takes convex values as well as nonconvex values. 相似文献
110.