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.
At birth, your baby's brain will have over 100 billion neurons. Considering that he started as a single cell nine months earlier, that is phenomenal growth. Fetal brain development begins in the second or third week of gestation -- weeks before many women know that they are pregnant -- and it continues into adulthood. Poor maternal nutrition can be quite damaging to the unborn child's brain development, which is why proper prenatal care is so important. Consult your health care provider if you are trying to conceive or suspect you are pregnant to make sure you are eating a healthy, well-balanced diet.