Snowflakes have at their heart a minute grain of dust that was once floating in a cloud, this speck of dust is the nucleation centre around which water vapour from the atmosphere can condense and if it is cold enough crystallise as ice. As with any crystallisation process it follows a symmetry intrinsic to the atoms or molecules from which the crystal is formed. In the case of water, the underlying symmetry is hexagonal symmetry. There’s more on this in the snow crystal primer.

Caltech’s Kenneth Libbrecht’s is the snowflake guru, here’s a video montage of his snow crystal gallery set to the tune of A Guy Called Gerald by Humanity (Borngraber & Struver Remix):

One question that puzzled me as a child is how each of the six arms “knows” to grow in the same way? Well, they’re growing under almost identical conditions so that might be expected, except, of course, that pretty drawings and diagrams aside, the six arms of snow crystals don’t actually grow symmetrically at all. At first glance they might look nice and symmetrical but under the microscope a single snow crystal will be seen to be far less than perfect in its symmetry. Symmetrical snow crystals are very rare except on Christmas cards. Speaking of which I abandoned my Christmas rant about octagonal and pentagonal snowflakes which are common in those pretty pictures but are physically impossible in the real world of snow because of symmetry constraints.

Shape of snowflakes is a post from: Sciencebase Science Blog

The aurorae are a natural light show in the sky, most commonly seen at high latitudes (Arctic and Antarctic). They are caused by the collision of energetic charged particles from the sun (the solar wind) at high altitudes (thermosphere). The northern lights are named for the Roman goddess of the dawn, Aurora, and the Greek name for the north wind, Boreas, after Pierre Gassendi, 1621.

“The northern lights are in my mind, They guide me back to you” – Renaissance

Photo: US Air Force photo by Senior Airman Joshua Strang. Eielson Air Force Base, Alaska, Aurora Borealis glowing above Bear Lake.

The Northern Lights are in my mind is a post from: Sciencebase Science Blog

NHS Choices, as ever, dissects the study, saying that the research may have homed in on the specific signalling pathway through which luteolin can kill bowel cancer cells in the laboratory. The study did not investigate whether upping one’s intake of luteolin-rich foods would have any effect on bowel cancer risk.

The lab study is an essential first step to understanding whether luteolin or more likely a chemical cousin might eventually be developed as an anticancer drug, although this is preliminary, fundamental molecular biology not clinical testing and animal studies for initial testing of such a compound are still a long way off. A drug might never emerge from this research.

Luteolin is found in celery, green pepper, thyme, dandelion, perilla, chamomile tea, carrots, olive oil, peppermint, rosemary, navel oranges, and oregano, fruit rinds, woody barks, clover blossom and ragweed pollen. It has also been isolated from Salvia tomentosa.

NHS Choices emphasises that, “It is important to remember that this study used pure luteolin, and not dietary sources of the compound. The effect of dietary luteolin on cancer is not clear from this research.” Of course, one has to presume that eating a diverse mixture of fresh fruit and vegetables as part of a well-balanced diet (whatever that means) is to be encouraged nevertheless.

Is antioxidant luteolin an anticancer super-nutrient? is a post from: Sciencebase Science Blog

Corn starch is a non-Newtonian fluid, which means it does not behave in a “classical” way, it undergoes shear thickening, which means it gets more viscous when a force is applied. You may have noticed it is much easier to stir it slowly than to try and stir it fast.

When the force applied is cyclic, as in the vibrations of the speaker cone, something very odd happens…weird tendrils form and crawl and collapse and regrow.

It’s also worth checking out the ferrofluid sculpture videos that show up when this Youtube clip finishes.

Cornstarch monsters on a speaker cone is a post from: Sciencebase Science Blog

“I think we can reasonably assume that any abdominal manipulation sufficient to disrupt adhesions would risk tissue damage and internal bleeding, but [visceral manipulation] is not likely to do that. As practiced, VM amounts to relaxation, suggestion, and gentle massage; so it is not likely to cause physical harm unless it replaces other, effective treatments. It’s more likely to cause harm to the wallet and to critical thinking.

From Science Based Medicine on VM

Visceral manipulation is a post from: Sciencebase Science Blog

There was a little confusion over whether or not the behaviour of the fluid is Newtonian or non-Newtonian. By definition, a Newtonian fluid is one in which the ratio of stress to strain rate is linear. Its graph would pass through the origin and the constant of proportionality is the fluid’s viscosity. A non-Newtonian fluid is any fluid that doesn’t follow that rule, by contrast. Examples include many salt solutions and molten polymers, ketchup (who knew?), custard, toothpaste, starch suspensions (check out cornstarch videos), paint, blood, and shampoo.

Viscous fluid on a moving belt is a post from: Sciencebase Science Blog

Bird flu scientists suspend work amid epidemic fears.

Bird flu research halted is a post from: Sciencebase Science Blog

I have to fast from 10pm the night before, wear loose clothing and trainers for the tests and bring along a fully indexed folder with all my meds (okay, it’s not that bad, just a short list, honest). They want to know if you have any X-ray procedures the week before the testing, presumably to avoid giving you a second (unnecessary) dose of radiation in a short time…oh and they ask you to confirm that you’re not pregnant.

In fact, aside from the very scary thought of discovering that I am perfectly fit and well, the worst outcome is that in order for them to attach a heart monitor that you wear for six days after the testing session they will have to shave off a patch of chest hair.

Needless to say, I will let you know how I get on…with the tests, not the shaving.

A hypochondriac’s dream is a post from: Sciencebase Science Blog

Drug-resistant strains have emerged before in Italy and Iran and multiple-resistant strains have been seen in China and Russia. This emergent strain has meant 12 patients have failed to respond to any antibiotics despite months of treatment. Three have died, the BBC reports.

The American Centers for Disease Control CDC confirmed that the Indian strain appears to be fully resistant to available antibiotics, the BBC says.

Incurable TB hits India is a post from: Sciencebase Science Blog

I was intrigued to start reading a comment just now on the post that started:

I take 4 medicines a day for Bipolar Disorder, OCD, ADHD & Depression. I have heard MANY people tell me how bad these medications are for me. But, the problem is, I am 17 & I don’t think that I can refuse medication yet. I live in Missouri & I don’t know what the law is here on refusing medication.

It was only as I got further into the rather long comment post that I spotted the author had signed themself “medicines” and used a rather dodgy-looking Yahoo email address. My immediate suspicion was that it was nothing more than a spam and as I got to the bottom of the comment the give away appeared with a spammy link to some online pharmacy. I did a quick search for a random snippet of text from the comment to confirm and found several sites on which the exact same comment had been posted. So almost certainly pure, uncut spam. Now sliced and diced by my blog spam filter and the IP address blacklisted.

Drug addict spam is a post from: Sciencebase Science Blog