Depending on which part of the nervous system is affected, symptoms could include headache, dizziness, memory loss, numbness, pain, vision problems, and difficulty walking. Mount Sinaiâs NeuroAIDS Program specializes in diagnosing and treating the full range of HIV-related neurological disorders.
Many greenhouse gases occur naturally in the atmosphere, such as carbon dioxide, methane, water vapor, and nitrous oxide, while others are synthetic. Those that are man-made include the chlorofluorocarbons (CFCs) , hydrofluorocarbons (HFCs) and Perfluorocarbons (PFCs), as well as sulfur hexafluoride (SF 6).
The Earth's atmosphere has remained much the same for the past 200 million years. The pie chart shows the proportions of the main gases in the atmosphere. It is clear that the main gas is nitrogen. Oxygen - the gas that allows animals and plants to respire, and fuels to burn - is the next most abundant gas. These two gases are both elements and account for about 99% of the gases in the atmosphere.