The human immunodeficiency virus (HIV) is a lentivirus (a subgroup of retrovirus) that causes HIV infection and acquired immunodeficiency syndrome (AIDS).AIDS is a condition in humans in which progressive failure of the immune system allows life-threatening opportunistic infections and cancers to thrive.Without treatment, average survival time after infection with HIV is estimated to be 9 to 11 years, depending on the HIV subtype.IDS is a condition in humans in which progressive failure of the immune system allows life-threatening opportunistic infections and cancers to thrive. Without treatment, average survival time after infection with HIV is estimated to be 9 to 11 years, depending on the HIV subtype.
Black Tortoise. The Black Tortoise or Black Turtle is one of the Four Symbols of the Chinese constellations. Despite its English name, it is usually depicted as a turtle entwined together with a snake. Further, in East Asia, it is not called after either animal but is instead known as the Black Warrior under various local pronunciations.
Black Scoters are large, mostly black or dark gray sea ducks. Formerly called the Common Scoter, the Black Scoter is the least common of the three scoters. Adult males are solid black with a bulbous yellow knob on an otherwise black bill. Females and juveniles are dark gray, lighter on the cheek with a dark cap. Their bills are dark and lack the knob found in adult males.