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Keywords: Analytic functions Multivalent prestarlike function Linear operator Hadamard product Subordination a b s t r a c t In the paper we introduce general classes of multivalent analytic functions defined by the subordination. In particular, we define the class of multivalent prestarlike functions. By using the Ruscheweyh's duality theory we investigate convolution properties related to mul...

In present paper a certain convolution operator of analytic functions is defined. Moreover, subordination and superordination- preserving properties for a class of analytic operators defined on the space of normalized analytic functions in the open unit disk is obtained. We also apply this to obtain sandwich results and generalizations of some known results.

By making use of a subordination theorem for analytic functions, we derive several subordination relationships between certain subclasses of analytic functions which are defined by means of the Sălăgean derivative operator. Some interesting corollaries and consequences of our results are also considered. c © 2007 Elsevier Ltd. All rights reserved.

By making use of subordination between analytic functions and the Dziok-Srivastava operator, we introduce a new subclass of multivalent analytic functions. Such results as inclusion relationship, integral presentations and convolution properties for this function class are proved.

In this paper, we define new subclasses ${S}^{*}_{q}(alpha,Phi),$ ${M}_{q}(alpha,Phi)$ and ${L}_{q}(alpha,Phi)$ of analytic functions in the space of logistic sigmoid functions based on quasi--subordination and determine the initial coefficient estimates $|a_2|$ and $|a_3|$ and also determine the relevant connection to the classical Fekete--Szeg"o inequalities. Further, we discuss the improved ...

Making use of the principle of subordination between analytic functions and a family of integral operators defined on the space of meromorphic functions, we introduce and investigate some new subclasses of meromorphic functions. Such results as inclusion relationships and integralpreserving properties associated with these subclasses are proved. Several subordination and superordination results...