Goitre related to hypermetabolism, (increased metabolism), excessive thyroid hormone, an increase in oxygen consumption, metabolic changes in protein metabolism, immunologic stimulation of diffuse goitre, and ocular changes (exophthalmos). Hypothyroid individuals may have weight gain despite poor appetite, cold intolerance, constipation and lethargy. However, these symptoms are often non-specific and make diagnosis difficult. A goitre may be classified either as nodular or diffuse. Nodular goitres are either of one nodule (uninodular) or of multiple nodules (multinodular). Worldwide, the most common cause for goitre is iodine deficiency, usually seen in countries that do not use iodized salt. Selenium deficiency is also considered a
Trace field of a representation Trace field of a representation In mathematics, the trace field of a linear group is the field generated by the traces of its elements. It is mostly studied for Kleinian and Fuchsian groups, though related objects are used in the theory of lattices in Lie groups, often under the name "field of definition". Fuchsian groups are discrete subgroups of formula_1. The trace of an element in formula_1 is well-defined up to sign (by taking the trace of an arbitrary preimage in formula_3) and the "trace field" of formula_4 is the field generated over formula_5 by the traces of all elements