On the Statistical Expectation and Evaluation of Centriole Orientations in Cell Profiles
نویسندگان
چکیده
In a paper by Stubblefield and Brinkley (I), the authors raise the question whether the observed frequencies of three categories of sections through centrioles are consistent with the assumption of random orientation of the centriole in a sectioned cell. In order to test this assumption we will compute the expected frequencies, which requires only elementary calculus, and compare them with the observed values by means of the chi-square statistical goodness-of-ft test. In a first approximation we assume that the centriole is a cylinder; determining the expected frequencies then amounts to computing the probabilities that the intersection of the interior of two parallel planes with a randomly oriented cylinder falls into the respective category. The three categories of sections were firstly defined as follows: 1. Cross-section (Fig. 1): The plane closer to the center of the cylinder intersects only the perimeter (i.e., not one or both of the ends) of the cylinder and at such an angle that the projections of the intersections of a cylindrical tubule (oriented parallel to the cylinder) with the two planes overlap; 2. Longitudinal section (Fig. 2) : The plane closer to the center of the cylinder does not intersect the perimeter (i.e., it intersects both bases of the cylinder) ; Oblique section." All other intersections not defined as crossor longitudinal sections. 3.
منابع مشابه
P-229: Chromosomal Analysis of Parthenogenetic Mouse Embryos Generated from In Vitro Activated Oocytes by Hydrostatic Pressure and Ethanol and Cytochalasin B
Background: Studies of preimplantation stage embryos by classic cytogenetic techniques have limitations, starting with the need for good metaphase stage when only one third of all analyzed embryos may show good quality metaphases. The incidence of chromosome anomalies in embryos produced by in vitro procedures is generally higher than that of embryos formed in vivo. Pressure specifically affect...
متن کاملCurriculum Orientations among Faculty: The Role of Gender, Academic Level and Learning Approach (Face-To-Face and Virtual) in Mashhad University of Medical Sciences
Introduction: Curriculum orientations are effective in curriculum success and failure. This study aimed to investigate faculties’ curriculum orientations based on gender, academic level and teaching approaches. Methods: This cross-sectional descriptive research was conducted in Mashhad University of Medical Sciences in 2011. The research population included the faculty of Mashhad University of...
متن کاملOn the Evaluation of Lexical Profiles in the Iranian High School and University EFL Text Books
متن کامل
Loss of Load Expectation Assessment in Deregulated Power Systems Using Monte Carlo Simulation and Intelligent Systems
Deregulation policy has caused some changes in the concepts of power systems reliability assessment and enhancement. In this paper, generation reliability is considered, and a method for its assessment using intelligent systems is proposed. Also, because of power market and generators’ forced outages stochastic behavior, Monte Carlo Simulation is used for reliability evaluation. Generation r...
متن کاملInvestigating the effect of strategic orientations and the role of organizational ambidexterity on academic brand reputation
Today, increasing competition in the education sector shows the growing importance of the university brand in educational institutions. Therefore, this study shows the factors affecting the brand performance of the university and the effect of using two strategic orientations simultaneously (entrepreneurial orientation and interactive orientation) on brand performance with the mediating role of...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- The Journal of Cell Biology
دوره 30 شماره
صفحات -
تاریخ انتشار 1966