No effect of GH/IGF-1 excess on adrenal gland in Acromegalic patients.

The sonographic pattern of neck lymph nodes in chronic autoimmune thyroiditis.

Background: Neck lymph nodes may be involved in the pathogenesis of chronic autoimmune thyroiditis (CAT).We hypothesized that the involvement of cervical lymph nodes in CAT may be associated with a different sonographic pattern of neck nodes in comparison to subjects without CAT. Methods: We included 106 patients (92 females and 14 males) with CAT and 70 control subjects (53 females andm17 males) without clinical, biochemical, and ultrasonographic evidence of thyroid and neck diseases. We performed laboratory tests (thyrotropin, antithyroperoxidase antibodies, antithyroglobulin antibodies, and ultrasonography) to evaluate in each group: (i) thyroid function, autoimmunity, and morphology; (i…

Fixed Point Theorems with Applications to the Solvability of Operator Equations and Inclusions on Function Spaces

Fixed point theory is an elegant mathematical theory which is a beautiful mixture of analysis, topology, and geometry. It is an interdisciplinary theory which provides powerful tools for the solvability of central problems in many areas of current interest in mathematics and other quantitative sciences, such as physics, engineering, biology, and economy. In fact, the existence of linear and nonlinear problems is frequently transformed into fixed point problems, for example, the existence of solutions to partial differential equations, the existence of solutions to integral equations, and the existence of periodic orbits in dynamical systems. This makes fixed point theory a topical area and …

Special Issue on Ciric type fixed point theorems

Professor Ljubomir Ćirić was born on August 13, 1935 in Resnik, environmentof the Niš, in Serbia. Primary,secondary and university education Professor Ćirić received in Belgrade, where he completed his Mr Sci and his Dr Sci in 1969. His fields of specialization are Fixed point theory and Nonlinear analysis. He has been founder of different directions in the theory of fixed points, which and in today's time are in the full development. During the past 45 years, he has given significant contributions to these areas. We want point out that his works have been published and cited in prestigious international journals. Two of his work has been cited in the Web of Science over 560 times, each ove…

Optimization Problems via Best Proximity Point Analysis

Many problems arising in different areas of mathematics, such as optimization, variational analysis, and differential equations, can be modeled as equations of the form Tx=x, where T is a given mapping in the framework of a metric space. However, such equation does not necessarily possess a solution if T happens to be nonself-mapping. In such situations, one speculates to determine an approximate solution x (called a best proximity point) that is optimal in the sense that the distance between x and Tx is minimum. The aim of best proximity point analysis is to provide sufficient conditions that assure the existence and uniqueness of a best proximity point. This special issue is focused on th…

Recent Developments on Fixed Point Theory in Function Spaces and Applications to Control and Optimization Problems

Nonlinear and Convex Analysis have as one of their goals solving equilibrium problems arising in applied sciences. In fact, a lot of these problems can be modelled in an abstract form of an equation (algebraic, functional, differential, integral, etc.), and this can be further transferred into a form of a fixed point problem of a certain operator. In this context, finding solutions of fixed point problems, or at least proving that such solutions exist and can be approximately computed, is a very interesting area of research. The Banach Contraction Principle is one of the cornerstones in the development of Nonlinear Analysis, in general, and metric fixed point theory, in particular. This pri…