A New Iterative Method for Finding Approximate Inverses of Complex Matrices

This paper presents a new iterative method for computing the approximate inverse of nonsingular matrices. The analytical discussion of the method is included to demonstrate its convergence behavior. As a matter of fact, it is proven that the suggested scheme possesses tenth order of convergence. Finally, its performance is illustrated by numerical examples on different matrices

Comparison of dietary intake between fixed orthodontic patients and control subjects.

BACKGROUND Adolescence is a period of rapid physiological and psychological development which is associated with an increased demand in nutritional requirements. Orthodontic therapy is also commonly initiated during this phase of life and nutritional intake may also change during treatment. Aims: To compare the nutrient intakes of adolescents wearing fixed orthodontic appliances and a control group matched for age and gender. METHOD A total of 180 patients aged between 15 and 17 years participated in this study (90 in the study group and 90 controls). Demographic data were collected by questionnaire and dietary intake was assessed using a 24-hour memory recall and was analysed using Dietplan6 software (Forestfield Software Ltd, UK). Comparisons between groups were assessed by the Independent sample t-test dnd the SPSS was used for statistical analysis. RESULTS Orthodontic patients consumed a similar number of total calories, protein and carbohydrate (p > 0.05); however, they had a greater intake of total fat, saturated fat, monosaturated fat, polysaturated fat, linolenic fat, linoleic fat and cholesterol and significantly lower intake of fibre, chromium and beta-carotene (p < 0.05) compared with the Control group. The intake of other macro- and micro-nutrients did not differ significantly between groups. CONCLUSIONS Adolescents receiving orthodontic treatment have an altered dietary intake that can be harmful to their health. As adolescents are at a critical stage of development and dietary intake is of particular importance, it is recommended that targeted nutritional guidance is provided to patients during orthodontic treatment