There was a time when I could hide my gray hairs with some strategic combing. Now, I have succumbed and describe my new hair color as “executive blond.” Of course, that also means that the important stuff under my scalp is getting older too. Brains start to “go gray” about the same time the hair does, which is why exercise for older adults has become the new anti-aging fix for our senior cerebellums. Several new studies provide more evidence that a brain in motion tends to remain... young.

The Dutch translation of Ray Kurzweil's 2005 bestseller “The Singularity is Near: When Humans Transcend Biology” (the title says it all!) is about to be released, so this post on 'practical PAC' will be a summary of my objections to this idea. The Singularity was a case study in my research to see if I could analyse the claims with PAC.

Continued from the last post.

Discounting the Bohmian song and dance, we are led to conclude that each electron does in some sense pass through both slits. But in what sense? Saying that an electron went through both slits cannot be equivalent to saying that the electron went through L and that it went through R, for to ascertain the truth of a conjunction we must individually ascertain the truths of its components, and we never find that an electron launched at G and detected at D has taken the left slit and that it has taken the right slit.

Calliope, like any Low Earth Orbit satellite (LEO), is going up to, well, LEO.  Space weather-- radiation and energetic particles emitted from an active Sun-- can damage satellites.  This region of space is partially protected from the worst effects of space weather by the Earth's ionosphere, but it is an active and threatening place.

If space wasn't active, there wouldn't be any point in sending up Calliope to measure it.  However, we'd prefer to keep the physical damage to the electronics to a minimum.  The primary source of damage due to solar activity is due to highly energetic electrons, protons and ions emitted by the Sun.

The last posts in this series will discuss some of the practical issues of performing research on complex themes.

Whether you agree or not, the funding machine for solar and wind energy is in motion and it is hard to stop - look at the debate over ending ethanol subsidies.

One way to make an informed policy decision is to truly know just how much solar energy will be provided in a 'smart' grid scenario, beyond optimistic projections by lobbyists.   U.C. San Diego Professor Jan Kleissl and Matthew Lave, a Ph.D. student in the Department of Mechanical and Aerospace Engineering at the Jacobs School, say they can do it. They developed a software program that allows power grid managers to predict fluctuations in the solar grid caused by changes in the cloud cover - and even discovered a solar variability 'law'.

Researchers say that a protein expressed in the human retina, human cryptochrome 2 protein (hCRY2), can sense magnetic fields when implanted into Drosophila, leading to an interesting topic in sensory biology; perhaps humans have an innate magnetic sense.

Migratory birds and sea turtles do, and that ability to sense the Earth's magnetic field is how they navigate long-distance voyages during migration.

A study in Canada says Canadian pre-schoolers prefer to play with kids more like them.

Are Canadian parents ingraining bias in their kids?  Or French-Canadians?  Hard to know. Participants were recruited from six daycares located in Montreal and its suburbs: 30 mostly second-generation Asian-Canadians and 30 French-Canadians. Children were paired with peers they had known for at least three months. According to the research team, social mores likely prompted a lack of interaction between cultures.   

By using two types of nanoparticles, drug delivery to tumors could be increased significantly. At the moment, several drug-delivering nanoparticles are already being used in clinical trials to combat tumors. A team at MIT decided to use two distinct particles, each with its own job, one to locate the tumor, and another one to deliver the drugs, all the while making use of the body’s own blood clotting system.