Trachea emergency situation, and this is a cricothyrotomy. Tracheal agenesis, is a rare birth defect in which the trachea fails to develop. The defect is usually fatal though sometimes surgical intervention has been successful. A tracheoesophageal fistula is a congenital defect in which the trachea and esophagus are abnormally connected. Sometimes as an anatomical variation one or more of the tracheal rings are completely formed. These "O" rings are smaller than the normal C-shaped and can cause narrowing of the trachea resulting in breathing difficulties. An operation called a "slide tracheoplasty" can be performed which opens up the rings and rejoins
Human-body model primarily for manufacturing environments to quantify a integrated circuit to survive the manufacturing process. A similar standard, IEC 61000-4-2, is used for system level testing and quantifies protection levels for a real world ESD event in an uncontrolled environment. In both JS-001-2012 and MIL-STD-883H the charged human body is modeled by a 100 pF capacitor and a 1500 ohm discharging resistance. During testing, the capacitor is fully charged to several kilovolts (2 kV, 4 kV, 6 kV and 8 kV are typical standard levels) and then discharged through the resistor connected in series to the device under test. Human-body model