It seems to have worked pretty well, in that the only debates within physics on this topic tend to come from older scientists with political agendas. One can, for instance, look up the APS position on climate change.
The people writing the checks need to better understand that these scientists are the main reason that the US economy does as well as it does. We have had and to date maintain a significant advantage over other nation states in terms of our technological innovation. However, it is undeniable that other countries are fast catching up. Our technological advantage is not a given thing, we have to properly fund R&D for it to be maintained. Technological prowess leads to economic health.
Think of photons as the central point from which oscillating magnetic and electric fields originate. And that this point moves through space at ~3x10^8 m/s. It is kind of like throwing two stones into water and watching the resulting interference patterns, excepts that the centers of those patterns are moving instead of stationary. Hence, collision isn't really an apt description.
Disclaimer: I am a physicist who works in MRI. MRI can be used to measure concentrations of certain biochemicals. MRI is sensitive enough to different proton-containing species that the frequency difference between fat and water causes image artifacts that can pose great difficulty. Not all biomolecules are sufficiently concentrated in the brain, or have a spectrum that is unique enough to be measured in vivo. A good example of a brain chemical that can be measured is N-acetyl aspartate (NAA), which has a proton peak at around 2 ppm that doesn't overlap with much else. Magnetic resonance spectroscopy is very difficult, and is most easily accomplished on research scanners operating at 3 tesla or higher. The reason for this is that rather than letting all hydrogen nuclei contribute to one signal that is then spatially located, one must parse what kinds of nuclei (i.e. what their chemical shift is) within each voxel. This not only imposes technical difficulties, but reduces the signal to noise ratio, potentially requiring more signal averaging in order to see sufficient signal above the noise floor.
"The last supernova in our galaxy occurred several hundred years ago." If that were true, we'd would not have detected it yet. If we had, we'd all be dead. Think about it.
mernilio writes "According to UPI: 'A Massachusetts school district superintendent said a memo banning sixth graders from carrying pencils was written without district approval. North Brookfield School District interim Superintendent Gordon Noseworthy said Wendy Scott, one of two sixth-grade teachers at North Brookfield Elementary School, did not get approval from administrators before sending the memo to all sixth-grade parents, the Worcester Telegram & Gazette reported Thursday. The memo said students would no longer be allowed to bring writing implements to school. It said pencils would be provided for students in class and any students caught with pencils or pens after Nov. 15 would face disciplinary action for having materials 'to build weapons.'"
digitaldc writes "Pollution in Beijing was so bad Friday the US embassy, which has been independently monitoring air quality, ran out of conventional adjectives to describe it, at one point saying it was 'crazy bad.' The embassy later deleted the phrase, saying it was an 'incorrect' description and it would revise the language to use when the air quality index goes above 500, its highest point and a level considered hazardous for all people by US standards. The hazardous haze has forced schools to stop outdoor exercises, and health experts asked residents, especially those with respiratory problems, the elderly and children, to stay indoors."
Ohio STATE University. Not Ohio University. There is a huge world of difference. And PR is important, relying on the general media to disseminate information from original scientific journal articles doesn't work. Scientists should be the ones presenting their work, not journalists who are at best mildly fluent in the research areas they cover.
An anonymous reader writes "While Douglas Adams continues his attempt to set a new record for the longest extended lunch break, geeks all over the universe pay tribute to the beloved author by celebrating the tenth edition of Towel Day. Towel Day is more alive than ever. This year Richard Dawkins, one of Adams' best friends, has tweeted a Towel Day reminder to his numerous followers. The CERN Bulletin has published an article on Towel Day. There has been TV coverage and there will be a radio interview. The Military Republic of the Deltan Imperium, a newly formed micronation, has recognized Towel Day as an official holiday. In Hungary several hundreds of hitchhiker fans want to have a picnic together in a park. And there's a concert, a free downloadable nerdrap album, a free game being released, the list goes on and on."
Iron Nose writes with an account from Byte Size Biology of horizontal gene transfer from a fungus to an insect. The author suspects that we will see lots more of this as we sequence more genomes. "The pea aphid is known for having two different colors, green and red, but until now it was not clear how the aphids got their color. Aphids feed on sap, and sap does not contain carotenoids, a common pigment synthesized by plants, fungi, and microbes, but not by animals. Carotenoids in the diet gives many animals, from insects to flamingos, their exterior color after they ingest it, but aphids do not seem to eat carotenoid-containing food. Nancy Moran and Tyler Jarvik from the University of Arizona looked at the recently sequenced genome of the pea aphid. They were surprised to find genes for synthesizing carotenoids; this is the first time carotenoid synthesizing genes have been found in animals. When the researchers looked for the most similar genes to the aphid carotenoid synthesizing genes, they found that they came from fungi, which means they somehow jumped between fungi and aphids, in a process known as horizontal gene transfer."
Matt_dk writes "Spectacular satellite images suggest that Mars was warm enough to sustain lakes three billion years ago, a period that was previously thought to be too cold and arid to sustain water on the surface, according to research published today in the journal Geology. Earlier research had suggested that Mars had a warm and wet early history but that between 4 billion and 3.8 billion years ago, before the Hesperian Epoch, the planet lost most of its atmosphere and became cold and dry. In the new study, the researchers analysed detailed images from NASA’s Mars Reconnaissance Orbiter, which is currently circling the red planet, and concluded that there were later episodes where Mars experienced warm and wet periods."
An anonymous reader sends in this link to a video of 12-1/2 minutes of Space Shuttle pr0n. The people at the Johnson Space Center put together this video of the ascent of STS-129 using multiple imagery assets — ground, air, booster, and the shuttle itself. The booster's-eye view of splashdown and immersion is something you don't see every day. As a bonus, another anonymous reader shared a beautiful photo of the shuttle flying over rugged terrain after it separated from the ISS last week.
Researchers from the School of Medicine at the University of California have shown that the more germs a child is exposed to, the better their immune system in later life. Their study found that keeping a child's skin too clean impaired the skin's ability to heal itself. From the article: "'These germs are actually good for us,' said Professor Richard Gallo, who led the research. Common bacterial species, known as staphylococci, which can cause inflammation when under the skin, are 'good bacteria' when on the surface, where they can reduce inflammation."
harrymcc writes 'We now know that a remarkable percentage of consumers and businesses decided to spurn Windows Vista and stay with XP. But did the reviews of Vista serve as an early warning that it had major problems? I looked back at the evaluations in nine major publications and found that they expressed some caution--but on the whole, they were far from scathing. Some were downright enthusiastic.'
It detects the oxygenation of blood. The mechanism behind this is a different magnetic moment of oxygenated hemoglobin, oxygenated hemoglobin is diamagnetic vs paramagnetic while deoxygenated. This is called the BOLD effect (Blood Oxygen Level Dependent). The difference in the two conditions magnetic property affects the MRI signal lifetime in the near vicinity. This results in contrast developing between tissues with oxygenated blood vs tissue with deoxygenated blood. The idea behind fMRI is that when you use a certain part of the brain, it requires oxygenated blood, which will lead to contrast. Unfortunately, due to low overall signal strength/contrast-to-noise ratio, the image must be signal averaged. Hence if you were tapping your finger to see which part of your brain "lights up", you would have to repeat this action, and have your MRI scan be synced to your action so that the same part of the brian is being imaged over the same interval each time. It's tricky, but my understanding is that it's quite feasible. There are many other mechanisms for causing localized signal lifetime changes, without having RTFA, I can't be sure what they took under consideration.