Avascular necrosis (AVN) of the hip is an abnormal and possibly crippling condition in which blood cannot get to the hip bone. When the blood supply to the bone is blocked, the area without blood supply can die. This may lead to collapse of the bone requiring replacement with an artificial hip joint.
Nitrogen Fixing Trees for Permaculture Flowers of the leguminous tree, Kowhai, the national flower of New Zealand Nitrogen fixation is a pattern of nutrient cycling which has successfully been used in perennial agriculture for millennia. This article focuses on legumes, which are nitrogen fixers [â¦]
Nitrogen fixation occurs in nature either due to lightning or nitrogen-fixing bacteria. There are two broad groups of nitrogen-fixing bacteria. The first group includes the free-living bacteria that are not attached to any plant in particular and are found in the soil or in water. Examples of this group include the genera Clostridium and Azotobacter, as well as some blue-green algae.