: Methane is emitted during the production and transport of coal, natural gas, and oil. Methane emissions also result from livestock and other agricultural practices and by the decay of organic waste in municipal solid waste landfills.
Traumatic Brain Injury (TBI) - Levels of Severity. Mild TBI. Loss of consciousness is very brief, usually a few seconds or minutes. Loss of consciousness does not have to occur - the person may be dazed or confused. Testing and scans of the brain may appear normal. Most common: 75%-85% of all brain injuries are mild.
In general, symptoms of traumatic brain injury should lessen over time as the brain heals but sometimes the symptoms worsen because of the patient's inability to adapt to the brain injury. For this and other reasons, it is not uncommon for psychological problems to arise and worsen after brain injury.