statement of problem: due to the appearance of palatal height difference in orthodontic patients we decided to carry out this study. purpose: the purpose of this research was to determine palatal height in persons with normal occlusion and different malocclusions (class i, ii div i and iii) and comparing them with each other. materials and methods: in this cross sectional research, 240 subjects...

we consider the class of polynomial differential equation x&= , 2(,)(,)(,)nnmnmpxypxypxy++++2(,)(,)(,)nnmnmyqxyqxyqxy++&=++. for where and are homogeneous polynomials of degree i. inside this class of polynomial differential equation we consider a subclass of darboux integrable systems. moreover, under additional conditions we proved such darboux integrable systems can have at most 1 limit cycle.

extended abstractintroductionone of the basic challenges of governments, especially in developing countries, is to organize the desired national spatial structure in the changing urbanization. such a structure allows us to divide economic and social functions in the urban and regional hierarchy in a balanced manner. in most provinces and territories of iran, the urban hierarchy has formed compl...

This article is concerned with the defect indices of singular symmetric linear difference equations of order 2n with complex coefficients and one singular endpoint. We first show that the positive and negative defect indices d+ and dof a class of singular symmetric linear difference equations of order 2n with complex coefficients satisfy the inequalities n ≤ d+ = d≤ 2n and all values of this ra...

Consider a difference equation which takes the k-th largest output of m functions of the previousm terms of the sequence. If the functions are also allowed to change periodically as the difference equation evolves, this is analogous to a differential equation with periodic forcing. A large class of such non-autonomous difference equations are shown to converge to a periodic limit, which is inde...

Background. Physical education learning in the era of the COVID-19 pandemic has a remarkable impact on students’ creativity. Objectives. This study aims to determine the effect of applying the inquiry and discovery models in online physical education learning to develop high school students’ creativity. Methods. The multiple treatment and control with the pre and post-test procedure were used...