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The objective of this study was to investigate whether it is possible to use a lateral (profile) photograph to determine the underlying skeletal Class and which reference points of the angle of convexity are most suitable for this...
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The objective of this study was to investigate whether it is possible to use a lateral (profile) photograph to determine the underlying skeletal Class and which reference points of the angle of convexity are most suitable for this purpose. Profile photographs and lateral cephalographs included in the baseline data for 180 orthodontic patients were retrospectively evaluated. The subjects were assigned to skeletal Classes based on Wits values obtained by radiolographic analysis. The Class I subjects were 58 patients (22 males, 36 females) with an average age of 13.63 +/- 2.1 years, the Class II subjects 60 patients (37 males, 23 females) with an average age of 13.60 +/- 2.6 years, and the Class III subjects 62 patients (28 males, 34 females) with an average age of 11.65 +/- 3.3 years. The angles measured were A'OrB' (=POrA'-POrA'), A'N'B', and the angle of convexity with its variants (N'SnPog', N'A'Pog', TrSnPog', TrA'Pog', Gl'SnPog', and Gl'A'Pog'). These angles were statistically evaluated using a two-sided t-test and linear discriminant analysis. Class II and Class III subjects exhibited highly significant differences (P < 0.001) for all angles. Class I and Class III exhibited highly significant differences (P < 0.001) for almost all angles, and significant differences for A'N'B' (P < 0.05). Class I and Class II differed significantly (P < 0.05) only for some angles (N'SnPog', TrA'Pog', Gl'SnPog', and Gl'A'Pog'). The error within the linear discriminant analysis was smallest for N'SnPog', GlA'Pog', and TrA'Pog' angles. However, the method error according to Dahlberg yielded rather high values for all angles (1.07-1.17 degrees). Discrimination between skeletal Class I and Class III was easier than that between Class I and Class II. One of the reasons may be that the subclasses division I and division II were not distinguished within the Class II subjects.
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It is argued in this article that social psychology would make the greatest contribution to research on class identity if it concentrated on the area closest to psychology-analysis of class consciousness. In order to show that the...
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It is argued in this article that social psychology would make the greatest contribution to research on class identity if it concentrated on the area closest to psychology-analysis of class consciousness. In order to show that the study of the psyche and mentality of the middle class is one of the least researched aspects of the American middle class, a brief overview of the different approaches to the study of the middle class in selected disciplines will be offered. It will be demonstrated that even if the identity of the U. S. middle class cannot be fully understood without its history and the social context in which it operates, it is the study of its (un)consciousness that social psychology should be focusing its research efforts on. The alternative would make social psychology indistinguishable from social history or sociology.
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It is argued in this article that social psychology would make the greatest contribution to research on class identity if it concentrated on the area closest to psychology—analysis of class consciousness. In order to show that th...
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It is argued in this article that social psychology would make the greatest contribution to research on class identity if it concentrated on the area closest to psychology—analysis of class consciousness. In order to show that the study of the psyche and mentality of the middle class is one of the least researched aspects of the American middle class, a brief overview of the different approaches to the study of the middle class in selected disciplines will be offered. It will be demonstrated that even if the identity of the U.S. middle class cannot be fully understood without its history and the social context in which it operates, it is the study of its (un)consciousness that social psychology should be focusing its research efforts on. The alternative would make social psychology indistinguishable from social history or sociology.
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摘要 :
It is argued in this article that social psychology would make the greatest contribution to research on class identity if it concentrated on the area closest to psychology-analysis of class consciousness. In order to show that the...
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It is argued in this article that social psychology would make the greatest contribution to research on class identity if it concentrated on the area closest to psychology-analysis of class consciousness. In order to show that the study of the psyche and mentality of the middle class is one of the least researched aspects of the American middle class, a brief overview of the different approaches to the study of the middle class in selected disciplines will be offered. It will be demonstrated that even if the identity of the U. S. middle class cannot be fully understood without its history and the social context in which it operates, it is the study of its (un)consciousness that social psychology should be focusing its research efforts on. The alternative would make social psychology indistinguishable from social history or sociology.
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Let p1 and p2 be primes such that p1 ≡ p2 ≡ 5 (mod 8), i =√(?1), d = 2p1 p2,K = Q(√d, i), K_2~((1)) be the Hilbert 2-class field of K, K_2~((2)) be the Hilbert 2-class field of K_2~((1)), G be the Galois group of K_2~((2))/K a...
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Let p1 and p2 be primes such that p1 ≡ p2 ≡ 5 (mod 8), i =√(?1), d = 2p1 p2,K = Q(√d, i), K_2~((1)) be the Hilbert 2-class field of K, K_2~((2)) be the Hilbert 2-class field of K_2~((1)), G be the Galois group of K_2~((2))/K and K~((?)) = Q(√(p1), √(p2),√2, i) be the genus field of K. The 2-part C_(K,2) of the class group of K is of type (2, 2, 2). Our goal is to study the 2-class field tower of K and to calculate the order of G.
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An accurate anteroposterior measurement of jaw relationships is critically important in orthodontic diagnosis and treatment planning. The angular and linear measurements that have been proposed can be inaccurate because they depen...
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An accurate anteroposterior measurement of jaw relationships is critically important in orthodontic diagnosis and treatment planning. The angular and linear measurements that have been proposed can be inaccurate because they depend on various factors. The purpose of this study was to establish a new cephalometric measurement, named the Beta angle, to assess the sagittal jaw relationship with accuracy and reproducibility. This angle uses 3 skeletal landmarks-point A, point B, and the apparent axis of the condyle-to measure an angle that indicates the severity and the type of skeletal dysplasia in the sagittal dimension. Seventy-six pretreatment cephalometric radiographs of white patients were selected on the basis of 4 criteria that indicate a normal Class I skeletal pattern; the mean and the SD for the Beta angle were calculated. This group was compared with Class II and Class III skeletal pattern groups. After using the 1-way analysis of variance and the Newman-Keuls test and running receiver-operating-characteristics curves, we obtained results that showed that a patient with a Beta angle between 27 degrees and 35 degrees can be considered to have a Class I skeletal pattern. A more acute Beta angle indicates a Class II skeletal pattern, and a more obtuse Beta angle indicates a Class III skeletal pattern.
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Skeletal relationships in the sagittal plane do not always correspond with dental relationships. The aim of this study was to determine in which type of malocclusion the correlation between overjet and skeletal sagittal parameters...
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Skeletal relationships in the sagittal plane do not always correspond with dental relationships. The aim of this study was to determine in which type of malocclusion the correlation between overjet and skeletal sagittal parameters assessed by lateral cephalogram analysis is the highest. The extent to which overjet can predict skeletal relationships in the sagittal plane was also assessed. Eighty-three subjects fulfilled the inclusion criteria (40 males and 43 females, mean age 16.3 +/- 4.3 years). Overjet was measured on study casts and sagittal skeletal relationships were analysed on lateral cephalograms. ANB angle, Wits appraisal, and convexity at point A were determined. Mean values and standard deviations of measured parameters were calculated for Class I, Class II division 1, and Class III malocclusion subjects. Correlation between overjet measured on study casts and sagittal skeletal parameters measured on lateral cephalogram was calculated. Overjet as a predictor of skeletal relationships was assessed by means of linear regression analysis. A statistically significant positive correlation (P < 0.01) was found between the values of overjet and ANB (r = 0.690), overjet and Wits appraisal (r = 0.750), and overjet and convexity at point A (r = 0.608) when assessing the whole sample. When linear regression between overjet and cephalometric parameters was assessed separately in Class I, Class II division 1, and Class III malocclusion subjects, the percentage of variability was statistically significant in just four pairs. The findings show that overjet is a good predictor of sagittal relationship only in subjects with a Class II division 1 malocclusion.
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In this paper, assuming the Generalized Riemann Hypothesis, we determine all imaginary abelian number fields N of 2-power degrees with ideal class groups of exponents ≤ 2 for which the 2-ranks of the Galois group of N over Q are equal to 2.
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In this paper, we prove that there exists a infinite set of non-trivial local Fitting classes every element in which is decomposable as a non-trivial product of Fitting classes such that every factor in the product is neither loca...
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In this paper, we prove that there exists a infinite set of non-trivial local Fitting classes every element in which is decomposable as a non-trivial product of Fitting classes such that every factor in the product is neither local nor a formation. In particular, this gives a positive answer to Problem 11.25 a) in The Kourovka Notebook.
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