Non-Newtonian Fluid

A non-newtonian fluid’s viscosity changes when the gradient in flow speed changes. Colloidal suspensions and polymer solutions like ketchup and starch/water paste are non-Newtonian fluids. (Source)

GIF made by Sixpenceee. Original video via YouTube. 

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Radically Diverse Australian Fungi Photographed by Steve Axford

Photographer Steve Axford (previously) continues his quest to document some of the world’s most obscure fungi found in locations around Australia. Axford lives and works in the Northern Rivers area of New South Wales in Australia where he often has to travel no further than his own back yard to make some of the discoveries you see here. The forms of fungi, slime molds, and lichens he prefers to document seem to have no limit in their diverse characteristics. Axford explained when we first featured his work last year that he suspects many of the tropical species he stumbles onto are often completely undocumented. You can follow more of Axford’s discoveries on Flickr and SmugMug. Thanks Colossal

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Scientists Make Unclear Breakthrough After Giving Robot Cancer

“Never before has cancer been detected in a non-biological entity, which seems like a pretty big achievement to me. I mean, it took three years of experimentation just to get cancer to take hold inside a robot, and anything that requires that much effort probably ends up being pretty useful, I imagine.”

More.

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A mystery that began in southern Brazil: all over the country, waters are turning red. However, what many considered to be the prediction of End Times was actually a non-toxic bloom of red algae known as Mesodinium rubrum. Blooms of this red algae have occurred all over the world, from South Africa to Canada and even Antarctica.

(Source)

What were you taught about drugs?

Remember hearing about how even just trying an addictive drug once would mean you were hooked for good?

Well, that’s what Columbia University professor Carl Hart learned in school too.

So imagine his surprise when his own research into drug addiction revealed something very, very different.

Working with others, Hart revisited some long-standing research on lab rats that showed that rats would self-administer drugs until death. He learned that rats that live in sterile cages with nothing else to do chose to take drugs until they effectively committed suicide. But those offered alternatives to drugs — like sweets or sex — often chose the alternatives. 

In other words, the addictive behavior was caused by the environment, not some attribute of the drug itself.

Then Hart did something unusual. He invited human drug users into his lab. He set up an experiment where he offered regular meth users a choice between drugs or money.

When presented with an attractive alternative ($20), even people who regularly use a drug like meth still chose the alternative.

WATCH: Dr. Carl Hart’s talk on drug use, poverty, and U.S. drug laws.

The History of Trigonometry

From LiveScience.com:

Trigonometry follows a similar path as algebra: it was developed in the ancient Middle East and through trade and immigration moved to Greece, India, medieval Arabia and finally Europe (where consequently, colonialism made it the version most people are taught today). The timeline of trigonometric discovery is complicated by the fact that India and Arabia continued to excel in the study for centuries after the passing of knowledge across cultural borders. For example, Madhava’s 1400 discovery of the infinite series of sine was unknown to Europe up through Isaac Newton’s independent discovery in 1670. Due to these complications, we’ll focus exclusively on the discovery and passage of sine, cosine, and tangent.

Beginning in the Middle East, seventh-century B.C. scholars of Neo-Babylonia determined a technique for computing the rise times of fixed stars on the zodiac. It takes approximately 10 days for a different fixed star to rise just before dawn, and there are three fixed stars in each of the 12 zodiacal signs; 10 × 12 × 3 = 360. The number 360 is close enough to the 365.24 days in a year but far more convenient to work with. Nearly identical divisions are found in the texts of other ancient civilizations, such as Egypt and the Indus Valley. According to Uta Merzbach in “A History of Mathematics” (Wiley, 2011), the adaptation of this Babylonian technique by Greek scholar Hypsicles of Alexandria around 150 B.C. was likely the inspiration for Hipparchus of Nicea (190 to 120 B.C.) to begin the trend of cutting the circle into 360 degrees. Using geometry, Hipparchus determined trigonometric values (for a function no longer used) for increments of 7.5 degrees (a 48th of a circle). Ptolemy of Alexandria (A.D. 90 to 168), in his A.D. 148 “Almagest”, furthered the work of Hipparchus by determining trigonometric values for increments of 0.5 degrees (a 720th of a circle) from 0 to 180 degrees.

The oldest record of the sine function comes from fifth-century India in the work of Aryabhata (476 to 550). Verse 1.12 of the “Aryabhatiya” (499), instead of representing angles in degrees, contains a list of sequential differences of sines of twenty-fourths of a right angle (increments of 3.75 degrees). This was the launching point for much of trigonometry for centuries to come.

The next group of great scholars to inherit trigonometry were from the Golden Age of Islam. Al-Ma'mun (813 to 833), the seventh caliph of the Abbasid Caliphate and creator of the House of Wisdom in Baghdad, sponsored the translation of Ptolemy’s “Almagest” and Aryabhata’s “Aryabhatiya” into Arabic. Soon after, Al-Khwārizmī (780 to 850) produced accurate sine and cosine tables in “Zīj al-Sindhind” (820). It is through this work that that knowledge of trigonometry first came to Europe. According to Gerald Toomer in the “Dictionary of Scientific Biography 7,” while the original Arabic version has been lost, it was edited around 1000 by al-Majriti of Al-Andalus (modern Spain), who likely added tables of tangents before Adelard of Bath (in South England) translated it into Latin in 1126.

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For people looking for History of Mathematics resources!

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Thinking alike changes how we speak

As social creatures, we tend to mimic each other’s posture, laughter, and other behaviors, including how we speak. Now a new study shows that people with similar views tend to more closely mirror, or align, each other’s speech patterns. In addition, people who are better at compromising align more closely.

“Few people are aware that they alter their word pronunciation, speech rate, and even the structure of their sentences during conversation,” explained Florian Jaeger, associate professor of brain and cognitive sciences at the University of Rochester and coauthor of the study recently published in Language Variation and Change. “What we have found is that the degree to which speakers align is socially mediated.”

“Our social judgments about others and our general attitude toward conflict are affecting even the most automatic and subconscious aspects of how we express ourselves with language,” said lead-author Kodi Weatherholtz, a post-doctoral researcher in Jaeger’s lab.

To test the social effects of how greatly we mimic each other’s speech patterns, the researchers devised an experiment in which participants first listened to ideologically charged messages with a set sentence structure. After listening to the diatribes they were asked to describe some simple illustrations showing characters performing simple actions, such as a waitress giving a banana to a monk.

Most participants subconsciously aligned their descriptions with the sentence structure presented in the listening phase of the experiment. But, how closely the participants aligned with the speaker varied based on how much they agreed with the speaker’s views (as assessed in a post-experimental interview). Those who shared views with the speaker altered their speech to more closely match the sentence pattern used by the speaker.

During the experiment, participants heard phrases like “Congress is giving too much money to welfare moochers.” Others heard the same ideologically loaded sentiment expressed with a different sentence structure: “Congress is giving welfare moochers too much money.” (Notice the order of the phrases “too much money”—which refers to the thing being given—and “welfare moochers”—the recipient.)

Those who heard the first version, “Congress is giving too much money to welfare moochers” (the recipient is mentioned after the thing being given), for example, were more likely to describe a picture as “The waitress is giving a banana to the monk” rather than “The waitress is giving the monk a banana” when they agreed with the speaker’s views.

When participants disagreed with the opinion expressed by the speaker, they aligned less or not at all. Additionally, participants who described themselves as compromising in conflict situations, showed more linguistic alignment with the speaker.

One of the researchers, Kathryn Campbell-Kibler, an associate professor of linguistics at Ohio State University, pointed out that testing for political influences on syntactic alignment might be interesting in its own right, but the purpose in this experiment was to influence social similarity and establish a situation in which participants were ideologically invested.

One reason people tend to align certain speech patterns is because it facilitates communication, Jaeger said. When we align how we talk, then sounds, words, and sentence structures become more predictable,

In addition to this well-known psychological function, the study’s findings provide evidence that speech alignment serves a social function. Similarity is a powerful social force, Jaeger explained. In short, we tend to like people who share certain characteristics with us. Thus, speaking in a way that is more or less similar to others can be a subtle means of influencing liking, trust, and other interpersonal emotions.

The findings shed new light on the relationship between human psychology and social behavior, Jaeger said. They suggest that social factors “piggy back” on the subconscious process—which is primary—and can boost the degree of alignment. “The extent to which we align is moderated by the attitudes we have towards our conversation partner,” added Weatherholtz.

These two traditions—the psychological and the social—”are not necessarily competing; they can be complementary,” said Jaeger. “What’s been lacking in the research is a way to talk to both communities and bring them together.”

This gigantic flower is one of the stars of the new exhibition, Life at the Limits: Stories of Amazing Species. The titan arum flower rarely blooms, but when it does, the sight—and smell—can be utterly breathtaking. Visitors to Life at the Limits will be able to check out a life-sized model of this tropical giant, though they’ll be spared its scent—a powerful perfume that resembles the stench of rotting flesh. To some insects, it’s a seductive scent, one that lures potential pollinators toward the female parts of the flower where they can pick up pollen and carry it off to fertilize other flowers.

Meet more amazing creatures in Life at the Limits, open now.