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[Myelophthisis and gastric cancer. An unusual association]
No full textThe infiltration of the bone marrow y non-hematopoietic cells is called myelophthisis. In patients with gastric cancer, this invasion is extremely infrequent and the survival is usually less than three months. We present the case of a 35-year-old man with bone marrow involvement secondary to diffuse gastric carcinoma of signet ring cells
Electrostatic interaction energy between two coaxial parallel uniformly charged disks
No full textWe calculate exactly the electrostatic interaction energy between two coaxial parallel uniformly charged infinitely thin disks. For the sake of generality, it is assumed that the disks have different radii and contain different amounts of total electric charge. The results derived when expressed in one-dimensional integral form are very suitable for numerical calculations. An explicit analytical formula is provided for the electrostatic interaction energy between two disks with same radius in terms of a family of special functions known as complete elliptic integrals. The results obtained are applicable to various electrostatic models including the case of a circular parallel plate capacitor
Hypergeometric solutions for Coulomb self-energy model of uniformly charged hollow cylinder
No full textThe article aims at studying hypergeometric-type mathematical techniques based on the extension of a model previously used to describe the Coulomb self-energy of a uniformly charged a three-dimensional cylinder. The associated crossed term integral is investigated and solved by introducing a computational series built from hypergeometric-type terms for different values of parameters involved. The approach considered may be appealing for a broad audience of researchers working in mathematical physics or related disciplines
Multicultural Teacher Education Matters
Get PDFThis article focuses on the impact the demographic change in the student population in current K-12 classrooms has had on teacher education programs as it pertains to the preparation of culturally responsive preservice teachers. There exists an extensive body of literature that posits that the increase of cultural diversity in our current classrooms should be understood as a call for new teaching approaches that promote multicultural awareness among teacher educators to develop preservice teachers who exhibit culturally responsive teaching practices, behaviors, and attitudes. This comprehensive review of literature explored the current research on multicultural teacher education programs, and more specifically the challenges experienced and strategies adopted by teacher educators, while developing culturally responsive teachers. The problems associated with this review is the need for graduates of teacher education programs to have an understanding of culturally responsive pedagogy, and how teacher education programs can successfully produce culturally responsive teachers. Cultural responsiveness is important in modern education because of the diversity in society and in the educational system. Multicultural teacher education programs seek to address this issue by developing culturally responsive teachers, who will address human diversity as well as to promote social justice and equity in education
Performance and economic evaluation of differentiated multiple vacation queueing system with feedback and balked customers
Get PDFThe present paper deals with a single server feedback queueing system under two differentiated multiple vacations and balked customers. It is assumed that the service times of the two vacation types are exponentially distributed with different means. The steady-state probabilities of the model are obtained. Some important performance measures of the system are derived. Then, a cost model is developed. Further, a numerical study is presented
A Note on Asymptotic Normality of a Copula Function in Regression Model
Get PDFOver the last decade, there has been significant and rapid development of the theory of copulas. Much of the work has been motivated by their applications to stochastic processes, economics, risk management, finance, insurance, the environment (hydrology, climate, etc.), survival analysis, and medical sciences. In many statistical models. The copula approach is a way to solve the difficult problem of finding the whole bivariate or multivariate distribution. In this paper, we give the asymptotic normality of the copulas function in a regression model
Modified Gaussian Radial Basis Function Method for the Burgers Systems
Get PDFIn this paper, the systems of variable-coefficient coupled Burgers equation are solved by a free mesh method. The method is based on the collocation points with the modified Gaussian (MGA) radial basis function (RBF). Dependent parameters and independent parameters and their effect on the stability are shown. The accuracy and efficiency of the method has been checked by two examples. The results of numerical experiments are compared with analytical solutions by calculating errors infinity-norm
Laplace Adomian Decomposition Method to study Chemical ion transport through soil
Get PDFThe paper deals with a theoretical study of chemical ion transport in soil under a uniform external force in the transverse direction, where the soil is taken as porous medium. The problem is formulated in terms of boundary value problem that consists of a set of partial differential equations, which is subsequently converted to a system of ordinary differential equations by applying similarity transformation along with boundary layer approximation. The equations hence obtained are solved by utilizing Laplace Adomian Decomposition Method (LADM). The merit of this method lies in the fact that much of simplifying assumptions need not be made to solve the non-linear problem. The decomposition parameter is used only for grouping the terms, therefore, the nonlinearities is handled easily in the operator equation and accurate approximate solution are obtained for the said physical problem. The computational outcomes are introduced graphically. By utilizing parametric variety, it has been demonstrated that the intensity of the external pressure extensively influences the flow behavior
Fibonacci and Lucas Identities from Toeplitz–Hessenberg Matrices
Get PDFIn this paper, we consider determinants for some families of Toeplitz–Hessenberg matrices having various translates of the Fibonacci and Lucas numbers for the nonzero entries. These determinant formulas may also be rewritten as identities involving sums of products of Fibonacci and Lucas numbers and multinomial coefficients. Combinatorial proofs are provided of several of the determinants which make use of sign-changing involutions and the definition of the determinant as a signed sum over the symmetric group. This leads to a common generalization of the Fibonacci and Lucas determinant formulas in terms of the so-called Gibonacci numbers
Fuzzy Semi-S-irresolute Continuous Mappings in Šostak’s Fuzzy Topological Spaces
Get PDFIn this paper, the concepts of fuzzy semi-S-irresolute open map, fuzzy semi-S-irresolute closed map and fuzzy semi-S-irresolute homeomorphism to the fuzzy topological spaces in Šostak’s sense are introduced and studied. Some of their characteristic properties are considered. Also a comparison between these new types of functions are established by giving examples