Although it is well known that lack of dopamine causes the motor symptoms of Parkinson's disease, it is not clear why the dopamine-producing brain cells deteriorate.Genetic and pathological studies have revealed that various dysfunctional cellular processes, inflammation, and stress can all contribute to cell damage.lthough it is well known that lack of dopamine causes the motor symptoms of Parkinson's disease, it is not clear why the dopamine-producing brain cells deteriorate.
Earth Overshoot Day is an initiative of Global Footprint Network, an international think tank that coordinates research, develops methodological standards and provides decision-makers with tools to help the human economy operate within Earthâs ecological limits.
There are a few reasons why seasonal dates can vary from year to year. 1  A year is not an even number of days and neither are the seasons. 2  Another reason is that the Earth's elliptical orbit is changing its orientation relative to the Sun (it skews), which causes the Earth's axis to constantly point in a different direction, called precession.