So where does 85-90% of the pollution come from?
I'm assuming the impurities in the snow, except for the odd volcanic eruption, are black carbon emissions. This chart suggests Europe, China and the US are equally responsible. China and the US emit the most carbon dioxide which, since it is also emitted when burning fossil fuel, is a good second indicator of where the black carbon is coming from. The second graph seems to blame the US and China more then any individual European country but the EU still has their part to play.
China is burning more coal than the US, CN 65% - US 37%. However, they are also using more renewable energy sources then the US, ~28% vs 12% (US). Both China and the US are expanding their nuclear sectors to double capacity, currently China has 1% vs the US 19%. Worth to note is that the US uses a lot more natural gas then China does (%-wise) which adds to their CO2 emissions but not black carbon. Values for China and for the US.
Point is: everyone's to blame. Besides, Europe and the US have had 100 years to develop their industries so they should already have gotten past the 40 year old upstarts problems, right?
At the end of the article: "Our data suggest that neuronal reactivation during sleep is quite important for growing specific connections within the motor cortex," Dr. Gan adds.
That suggests that the sleep deprived mice might have created stronger connections if they had a second session on the treadmill while the others were sleeping. As I understand it the study provides physical evidence that current theories about how memories form are not false. Those theories include replaying neuron firing patterns during sleep. It's the 'physical evidence' that's important here from what I gather. The 'sleep helps with memory' is more of a headline.
I'm curious how this translate to humans and abstract thought. For me there seems to be a big difference between remembering how to move your arm and learning algebra.