The purpose of this paper is to introduce two subclasses of meromorphic functions by using Cho-Kwon-Srivastava operator and to investigate various characterizations for these subclasses.

By making use of the principle of subordination, we introduce a certain subclass of p valent analytic functions. Such results as subordination properties, convolution properties and distortion theorems are proved.

A theorem involving multivalent analytic functions is considered and then its certain consequences are given:

In the present paper we establish several strong dierential superordinations regarding the extended new operator RI m;;l dened by using the extended Ruscheweyh derivative and the extended multiplier transformation, RI m;;l : A n ! A n ; RI m;;l f(z; ) = (1 )R m f(z; ) + I (m;;l )f(z; ); z 2 U; 2 U; where R m f(z; ) denote the extended Ruscheweyh derivative, I (m;;l ) is the extended multiplier transformation and A n = ff 2 H(U U); f(z; ) = z + an+1 ( )z n+1 +:::; z2 U; 2 Ug is the class of normalized analytic functions.

The objective of this paper is to give some characterizations for a (Gaussian) hypergeometric function to be in a subclass of Sakaguchi type functions. Two subclasses S(;t ) and T (;t ) of Sakaguchi type functions in the open unit disc U are also discussed.

In this paper, we examine the convolutions of convex harmonic functions with some other classes of univalent harmonic functions dened by certain coecient conditions and prove that such convolutions belong to some well known classes of univalent harmonic functions.

In this paper, we introduce a new subclass of Σp,j by use of a linear operator,which is defined by Hadamard product and provide coefficient inequality, distortion theorem, neighborhood property, convexity and starlike radius of this subclass. Some convolution properties are also considered.