Osmium (from Greek á½ÏÎ¼Î® osme, smell) is a chemical element with symbol Os and atomic number 76. It is a hard, brittle, bluish-white transition metal in the platinum group that is found as a trace element in alloys, mostly in platinum ores. Osmium is the densest naturally occurring element, with a density of 7004225900000000000â 22.59 g/cm3. Its alloys with platinum, iridium, and other platinum-group metals are employed in fountain pen nibs, electrical contacts, and other applications where extreme durability and hardness are needed.
Goiter is a noncancerous enlargement of the thyroid gland. The most common cause of goiter worldwide is iodine deficiency in the diet. Goiter is often caused by (and a symptom of) hyperthyroidism in the United States, where iodized salt provides plenty of iodine.
Goiter. Goiter is an enlargement of the thyroid gland. The resulting bulge on the neck may become extremely large, but most simple goiters are brought under control before this happens. Occasionally a simple goiter may cause some difficulty in breathing and swallowing.ne or more nodules can be recognised. The most frequent cause of multinodular goitre is iodine deficiency. Nonâtoxic goitre means that the nodules do not secret thyroid hormones in an uncontrolled way. Total thyroidectomy is an operation that involves the surgical removal of the whole thyroid gland.