Chapter 21: The esophagus, trachea and main bronchi. Thoracic part of esophagus. The esophagus (figs. 21-1, 21-2 and 21-3) has cervical, thoracic, and abdominal parts, extending from the lower end of the pharynx (C6 vertebrae) to the cardiac opening of the stomach (T11 or 12 vertebral level).
Hi, The PSAT is a practice test for the SAT. Colleges do not see your scores, so there is no pressure to do well on it as a sophomore. However, juniors who take the PSAT can qualify for scholarships through the National Merit Scholarship Program if they are in the top 10% of test takers.
Virtual concatenation (VCAT) is an inverse multiplexing technique creating a large capacity payload container distributed over multiple smaller capacity TDM signals. These signals may be transported or routed independently.Virtual concatenation has been defined for SONET / SDH, OTN and PDH path signals.CAT helps in providing services at a lower cost and more quickly than contiguous concatenation. However, it creates differential delay whereby each path that is created, represented by a VT has a different propagational delay across the network. The difference in these delays is called differential delay (D).