BlogCadre - science

Periodic Table of Videos

Wed, 16 Jul 2008 23:32:13 -0500

Some folks over at the University of Nottingham put together The Periodic Table of Videos, which is an interactive table that plays a video about each element you click on. Check it out. You may learn something. Link.

Previously:
Google Image Top Result Periodic Table, Interactive Periodic Table, A Different Kind of Periodic Table Poster

Circadian Clock Driven By Food Availability

Wed, 28 May 2008 22:00:36 -0500

Jason wrote up a post over at Hackszine.com about an interesting study that was conducted over at Harvard Medical School about a second circadian clock in mammals.

There was an interview with Clifford Saper, a professor of Neurology and Neuroscience at Harvard Medical School, in last week's Science Friday. The discussion was about a study which was just published in the journal Science about a second circadian clock in mammals that is driven by food availability. The research suggests that this second clock evolved as a sleep-cycle "reset" mechanism which allows mammals to very quickly adapt to optimize their wake period and maximize the chances of finding food during times when food is scarce.

This starvation override can take effect after only 16 hours of fasting. When the fast is cancelled by a sufficient caloric intake (read: real food), the body will shift its natural wake time to coincide with the event. So if you want to ditch your jet lag, or if you want to get up earlier in the morning, it might be as simple as fasting for the 16 hours prior to the time you would like to wake up, then eat a big meal. Your body will then override its normal light-based rhythm and wake at that same time going forward.

Link [via Hackszine.com]

Electron Filmed for First Time

Tue, 26 Feb 2008 21:43:28 -0600

By using a new technique which uses attosecond pulses, scientists can now film an electron in motion.

Previously it was impossible to photograph electrons because of their extreme speediness, so scientists had to rely on more indirect methods. These methods could only measure the effect of an electron's movement, whereas the new technique can capture the entire event.

Extremely short flashes of light are necessary to capture an electron in motion. A technology developed within the last few years can generate short pulses of intense laser light, called attosecond pulses, to get the job done.

"It takes about 150 attoseconds for an electron to circle the nucleus of an atom. An attosecond is 10^-18 seconds long, or, expressed in another way: an attosecond is related to a second as a second is related to the age of the universe," said Johan Mauritsson of Lund University in Sweden.

Link to article.
Link to video.

Cloth Physics Simulation

Mon, 11 Feb 2008 22:28:05 -0600

This interactive cloth physics simulation may just trick you into learning. I never knew a piece of cloth could be so much fun. Link.

Sugar substitutes may not help in weight loss

Mon, 11 Feb 2008 21:39:59 -0600

Research is showing that artificial sweeteners may not be fooling our bodies into losing weight.

In a series of experiments, scientists at Purdue University compared weight gain and eating habits in rats whose diets were supplemented with sweetened food containing either zero-calorie saccharin or sugar. The report, published in Behavioral Neuroscience, presents some counterintuitive findings: Animals fed with artificially sweetened yogurt over a two-week period consumed more calories and gained more weight — mostly in the form of fat — than animals eating yogurt flavored with glucose, a natural, high-calorie sweetener. It's a continuation of work the Purdue group began in 2004, when they reported that animals consuming saccharin-sweetened liquids and snacks tended to eat more than animals fed high-calorie, sweetened foods. The new study, say the scientists, offers stronger evidence that how we eat may depend on automatic, conditioned responses to food that are beyond our control.

Link to full article.

Bible written on pinhead-size chip

Wed, 26 Dec 2007 22:10:03 -0600

In order to increase young people's interest in nanotechnology, scientists have managed to put a version of the Bible on a chip smaller than a pinhead.

The record for the smallest copy is held by a Bible measuring 2.8x3.4x1cm (1.1x1.3x0.4in), weighing 11.75g (0.4 ounces) and containing 1,514 pages.

The 0.5sq-mm (0.01sq-in) nano-Bible was written on a silicon surface covered with a thin layer of gold (20nanometres thick - 0.0002mm).

Link.

Rare Mummified Dinosaur Found

Mon, 03 Dec 2007 10:42:39 -0600

Scientists have uncovered a rare find: a 67-million-year-old mummified plant-eater that contains fossilized bones and skin tissue, and quite possibly muscle and organs.

Preserved by a natural fluke of time and chemistry, the four-ton mummified hadrosaur, a duck-billed herbivore common to North America, could reshape the understanding of dinosaurs and their habitat, its finders say.

"There is no doubt about it that this dinosaur is a very, very significant find," said Tyler Lyson, a graduate student in geology at Yale University who discovered the dinosaur in North Dakota.

Nicknamed Dakota, the hadrosaur is one of only five naturally preserved dinosaur mummies ever discovered. Unlike previous dinosaur mummies, which typically involve skin impressions pressed into bones, Dakota's entire skin envelope appears to remain largely intact.

Link.

What Google Won't Find

Fri, 14 Sep 2007 22:42:17 -0500

Scott Aaronson spoke at Google Cambridge a month ago on the topic of quantum computers, the limits imposed by physics, and search. His position is that there are probably fundamental physical limits to the problem of search, much like the limits to cpu speed or hard drive density. In fact, the latter provide a really nice illustration:

In particular, one of the few things physicists think they know about quantum gravity — one of the few things both the string theorists and their critics largely agree on — is that, at the so-called “Planck scale” of about 10^-33 centimeters or 10^-43 seconds, our usual notions of space and time are going to break down. As one manifestation of this, if you tried to build a clock that ticked more than about 10⁴³ times per second, that clock would use so much energy that it would collapse to a black hole. Ditto for a computer that performed more than about 10⁴³ operations per second, or for a hard disk that stored more than about 10⁶⁹ bits per square meter of surface area. (Together with the finiteness of the speed of light and the exponential expansion of the universe, this implies that, contrary to what you might have thought, there is a fundamental physical limit on how much disk space Gmail will ever be able to offer its subscribers…)

--more after the break--

Newsflash: Men Want Hot Women

Wed, 05 Sep 2007 18:34:02 -0500

Jason over at meshly writes:

CNN just broke the news of this groundbreaking study. Shattering all previous assumptions, science has proven conclusively that men seek attractive mates.

"Men's choices did not reflect their stated preferences, the researchers concluded. Instead, men appeared to base their decisions mostly on the women's physical attractiveness.

The men also appeared to be much less choosy. Men tended to select nearly every woman above a certain minimum attractiveness threshold, Todd said.

...The scientists said women were aware of the importance of their own attractiveness to men, and adjusted their expectations to select the more desirable guys."

Link.

Scientists turn peanut butter into diamonds

Thu, 28 Jun 2007 22:30:06 -0500

By utilizing ridiculously high pressures, scientists at Edinburgh University have been able to turn peanut butter into diamonds.

Edinburgh University experts say the feat is made possible by squeezing the paste between the tips of two diamonds creating a "stiletto heel effect".

Read the full article here.

Encyclopedia of Life

Wed, 09 May 2007 16:51:01 -0500

The Encyclopedia of Life is a new project in which the objective is to catalogue all known species of life in a single, online database:

Comprehensive, collaborative, ever-growing, and personalized, the Encyclopedia of Life is an ecosystem of websites that makes all key information about life on Earth accessible to anyone, anywhere in the world. Our goal is to create a constantly evolving encyclopedia that lives on the Internet, with contributions from scientists and amateurs alike. To transform the science of biology, and inspire a new generation of scientists, by aggregating all known data about every living species. And ultimately, to increase our collective understanding of life on Earth, and safeguard the richest possible spectrum of biodiversity.

[via meshly]

Mouse Party, a look at the effects of drugs on mice

Mon, 23 Apr 2007 13:05:22 -0500

Mouse Party is a flash application put out by the University of Utah Genetics Learning Center which takes an interesting look at the effects of drugs on mice.

Take a look inside the brains of mice on drugs! Every drug of abuse has its own unique molecular mechanism. You'll learn how these various drugs disrupt the synapse to make the user feel "high".

Force of Light Moves Liquids

Thu, 29 Mar 2007 13:15:36 -0500

Scientists from the University of Chicago and University of Bordeaux have discovered that the pressure of light can move liquid.

In their experiment, the Bordeaux scientists shined a laser beam through a soapy liquid. The laser produced a long jet of liquid that broke up into droplets after traversing a surprisingly long distance.

"I thought this was just so weird because I know when liquid is supposed to break up, and this one isn't doing it," Zhang said.

Physicists know that lasers can set liquid in motion through heating effects, but heat was not a factor in this case. The liquid used in the Bordeaux experiment is a type that absorbs very little light. Heating the liquid would require more light absorption. In this case, the Chicago team's theoretical calculations matched the Bordeaux team's experimental results: the mild force of the light itself drives the liquid motion.

"Light is actually pushing onto us slightly. This effect is called radiation pressure," Zhang said.

This new found technique may offer "a new way to control the flow of fluids through extremely narrow channels for biomedical and biotechnological applications.

Geneticists discover 'semi-identical' twins

Tue, 27 Mar 2007 21:55:13 -0500

US geneticists have discovered an unknown kind of twins which they have called semi-identical -- the twins are identical on their mother's side, but only share half of their father's DNA.

The twins are technically chimeras: that is, their cells are not genetically uniform. Some cells contain male cells with an X and Y chromosome, others have female cells bearing a double load of Xs. In the journal Human Genetics, the researchers report that the proportion of XY and XX cells varies depending on the kind of tissue being examined.
For the genes to be distributed in this way, two sperm cells must have fertilised a single egg. Some DNA from each sperm is present in each child.

Scientists create the world's only blue rose

Thu, 22 Mar 2007 14:11:37 -0500

Feast your eyes on the world's first and only blue rose.

From the article:

Australian and Japanese researchers have demonstrated the application of RNAi technology for gene replacement in plants, developing the world's only blue rose.

Breeders had attempted to make true blue roses for several years, but none had successfully bred roses with blue pigment until fairly recently. In its first commercial application in plants, technology was used to remove the gene encoding the enzyme dihydroflavonol reductase (DFR) in roses.