By some reports, the word samurai first appeared in the 12th century. For a long time, the samurai provided the main military force used against emishi and other clans. In the 1100s, two powerful clans served the emperor of Japan: the Taira clan, and the Minamoto clan. These two families became bitter rivals, and in 1192, Minamoto Yoritomo led his clan to victory over the Taira.
EEG measures brain activity and must demonstrate regular wave patterns to be considered valid. Therefore, by this rule the onset of life would be the time when fetal brain activity begins to exhibit regular wave patterns, which occurs fairly consistently around week 25. Previous to that time, the EEG only shows small bursts of activity without sustained firing of neurons.
Many fetal organs become fully developed during the first or early second trimester of a woman's pregnancy. The brain, however, begins to develop in the third week of pregnancy and continues developing throughout pregnancy and after birth.ntraventricular Hemorrhage (IVH). The most common and most feared problem in the brain of an extremely premature baby is intraventricular hemorrhage (bleeding that occurs in or around the cavities, or ventricles, of the brain).