Narcissists believe their personality and appearance is superior to others. Symptoms of narcissism include focusing only on one's self, lacking guilt and an inability to empathize. Narcissistic people tend to be vain. A marriage being undermined by narcissism might benefit from therapy.
Trocar: A sharply pointed shaft, usually with a three-sided point. A trocar may be used within a cannula, a hollow tube, designed to be inserted into a vein, artery, bone marrow or body cavity. The word trocar is derived from the French trois (three) + carre (side). Last Editorial Review: 6/9/2016.
Tracheid of oak shows pits along the walls. It is longer than a vessel element and has no perforation plates. Tracheids are elongated cells in the xylem of vascular plants that serve in the transport of water and mineral salts.Tracheids are one of two types of tracheary elements, vessel elements being the other. Tracheids, unlike vessel elements, do not have perforation plates.racheids provide most of the structural support in softwoods, where they are the major cell type. Because tracheids have a much higher surface to volume ratio compared to vessel elements, they serve to hold water against gravity (by adhesion) when transpiration is not occurring.