Flu-like Illness. One of the earliest HIV symptoms in men is a severe 'flu-like' illness, known as the 'seroconversion illness.'. Seroconversion is the point in time where a person's blood is converted from being HIV negative to HIV positive, by the production of antibodies.
Erosion causes the surface of mountains to be younger than the rocks that form the mountains themselves. Glacial processes produce characteristic landforms, such as pyramidal peaks, knife-edge arÃªtes, and bowl-shaped cirques that can contain lakes.
Deep underneath newly-forming mountains, the rocks can heat up to over 1000C. Geologists have suspected this happens for some time. Now a study of ancient rocks reveals that they really were once heated to these unimaginable temperatures. Mountains form when rocks are forced upwards. But before this happens, the rocks that will make up the mountains first melt, over many millions of years.