TIME Chemistry

Octopus Skin Has Inspired a New Type of Camouflage Sheet

It can only switch from black to transparent and back again, but that's a start

Scientists have developed a color-changing device inspired by octopuses and their natural camouflaging techniques.

The research, carried out at the University of Houston and University of Illinois at Urbana–Champaign, looked at how the skins of octopuses, squid and cuttlefish can change color so rapidly. From there, researchers were able to design a heat-sensitive sheet that quickly changes color when detecting light.

At room temperature the flexible sheet is black. Once the device’s top layer, which contains a heat-sensitive dye, detects light it becomes transparent. True, this is hardly a rainbow of hues, but scientists believe it is the first step to developing a camouflage material for human use.

“[The device] is by no means a deployable camouflage system but it’s a pretty good starting point,” said a lead researcher, John Rogers of the University of Illinois at Urbana–Champaign, to National Geographic.

Popular Mechanics broke down the layers of the new device as follows:

The top layer of the new device is loaded with a temperature-sensitive dye that appears black at low temperatures and clear at temps above 116 degrees F. This dye-filled layer sits on top of a layer of white reflective silver tiles, an ultra-thin layer of silicon circuits that control the dye’s temperature, and a transparent silicone rubber foundation. All together, this stack measures less than 200 microns thick. (The average human hair is 100 microns wide.)

Underneath this flexible sandwich is a base layer containing an array of light-sensing photodetectors. The corners of each dye-filled pixel and silver tile above this photoreceptor layer are notched, creating gaps that are like holes in a mask, allowing light to get through to the photoreceptors so they know how and when to change color. This adaptive camouflage system can respond to changing patterns of illumination within just one to two seconds.

[National Geographic]

TIME Malaysia Airlines Flight 17

Lives Lost: Remembering Karlijn Keijzer, Indiana University Rower and Chemist

Ukraine Plane Indiana Victim
An undated photo of Karlijn Keijzer provided by Indiana University on July 18, 2014. Indiana University/AP

After helping transform the Hoosiers rowing program in the 2011 season, she turned to her PhD career as a scientist intent on fighting cancer and other diseases.

“I’m not an overly emotional person,” says Steve Peterson, the head women’s rowing coach at Indiana University.

But late Friday afternoon, while talking about Karlijn Keijzer (pronounced Kar-line Kite-ser)–a former Indiana University rower who was killed on Malaysia Airlines Fight 17 on Thursday–Peterson reached his breaking point. She was 25. “One of my favorite memories that keeps popping into my head, and it makes me so sad to say this,” Peterson says, unable to continue his words. Between several pauses to let the tears pass, he explains why he can no longer hide his grief. It was such a small thing, really, but it meant so much.

After every season, Peterson conducts exit interviews with his athletes. Keijzer was from the Netherlands, and under NCAA rules was eligible to row only one year while she pursued her graduate studies in chemistry. Keijzer was a key recruit for Peterson, who was looking to draw more international athletes, with more experience, to help keep Indiana competitive in the Big Ten. Keijzer was a terrific fit. She had competed in prestigious events, like the European Rowing Junior Championships and the World Rowing Junior Championships. She had Olympic aspirations.

During that 2011 season, she helped transform the Indiana program, leading the Hoosiers to a 14-5 record. She rowed with the Varsity 8 – “the big cheese,” says Peterson – and sat in the “stroke” position. In rowing, the stroke sits closest to the coxswain, and is not unlike the boat’s quarterback. “The stroke sets the rhythm, the pace,” says Peterson. “The best rower sits in the stroke seat.” Peterson calls Keijzer one of the best rowers he’s ever coached, and he’s been at it for 30 years.

But during that exit interview that Peterson can’t bear to describe, Keijzer didn’t want to talk about her own performance. “She was just encouraging me, telling me, “Your on the right path, keep doing what you’re doing,” says Peterson. Smitten with Bloomington, Keijzer wound up staying on the IU campus, ditching a potential rowing career for the school’s PhD program in chemistry. So this season, she saw Peterson’s team make it all the way to the NCAA championships for the first time in school history. Peterson traces this success directly back to Keijzer’s boat, which made IU nationally relevant and helped bolster recruiting. “After we finally made it, she says ‘I told you you can do it,’” says Peterson. “She was just so ridiculously supportive.”

The Malaysia Flight 17 tragedy has already cost so much. In Keijzer, a senseless act cost of group of rowers a beloved teammate, her fellow chemistry students a popular colleague, and the world a scientist intent on fighting cancer and other diseases.

David Giedroc, professor and chair of Indiana’s chemistry department, remembers Keijzer walking into his office as soon as she got on campus. She asked if he would advise him. “Here was this confident young lady, passionate about science and sports,” says Giedroc. “High level science and high level NCAA sports – that’s a fairly exotic combination for a graduate student.” During her first year at IU, when she was both rowing and studying, Keijzer would sometimes fall asleep in her lab chair. Still, she somehow managed to make the 6:00 am practices.

“We’d be in the locker room at 5:30, it would be windy, rainy,” says Jaclyn Riedel, one of Keijzer’s teammates. “But she was kind of leading the charge, cheering everyone on. She was just infectious.”The Amsterdam girl took to Indiana, calling herself a “Dutch Hoosier.” To fit in, she came to one party dressed as an ear of corn. “She wore black spandex, a long yellow shirt with frayed edges, and her hair was green,” says Riedel. Her teammates would ask her for informal Dutch lessons, and when they found out the word for garden gnome – kabouter – a select few, including Keijzer and Riedel, started calling themselves “the kabouters.” They headed to Home Depot to pick up a few statuettes. The gnomes became good luck charms. Riedel would carry one in her backpack, “though it never went into the boat,” she says.

After wrapping up her rowing career, Keijzer kept pursuing her doctorate. “As a computational chemist, she had enormous potential,” says Giedroc. This summer, Keijzer was working in the Netherlands, collaborating with researchers at VU University Amsterdam on simulations of anti-tumor drugs. At IU, she was working on developing a computer program that calculates how anti-cancer molecules interacted with partner proteins that might play a role in cancer or Alzheimer’s disease.

“She was so passionate pharmacological chemistry, and helping people that way,” says Meghan McCormick, Keijzer’s lab mate for four years. “Cancer was just one obstacle she was tackling. She also took on a project seeking better HPV vaccines.” Keijzer and McCormick were co-authors on a study just published in the Journal of the American Chemistry Society, titled: “Understanding Intrinsically Irreversible, Non-Nernstian, Two-Electron Redox Processes: A Combined Experimental and Computational Study of the Electrochemical Activation of Platinum(IV) Antitumor Prodrugs.” McCormick offers the lay explanation: “Many second and third generation cancer drugs aren’t working as well as they could be. We think we can make better ones, based on the methodology and tools that we used.” “She was just a strong woman,” says McCormick. “As a woman in science, a woman in chemistry, she was a big inspiration. We always felt like we had to prove ourselves a little bit more, to fight through the biases. We fed off each other’s strengths.” McCormick starts tearing up. “It’s certainly going to take a very long time to walk into that lab, and not see her sitting next to me,” says McCormick. “I’m so used to seeing her smiling at me, drinking coffee, giving me encouragement.”

Keijzer was on the Malaysia Airways flight with her boyfriend, bound for a summer vacation in Indonesia before she returned to Indiana. Kuala Lumpur was a layover. When Peterson, her old coach, got word from a former rower on Thursday that Keijzer was most likely on the plane, he was in a car with his family, on his way to visiting a friend in northern Ohio. He didn’t want to believe it. When he saw the confirmation on Keijzer’s Facebook page, the devastation set in.

“She was such an optimist,” says Peterson. “Not just for herself, but for her team, and for everybody around her. She was always there, smiling, a best friend. That’s now all cut way too short. That’s what really makes me sad.”

TIME Chemistry

Here’s Why You Shouldn’t Pee in the Pool

Besides being icky, it could also be very bad for you.

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Now that summer is here, there’s a good chance you might spend some of your time cooling off in a swimming pool. But, given that the average swimmer leaves behind 30 to 80 ml of urine when they go swimming, there might be more than just refreshment waiting for you in the water.

A recent study published in the American Chemical Society journal Environmental Science & Technology shows that mixing chlorine and uric acid — the latter of which is “almost entirely attributable to human urine” — can result in “volatile disinfection by-products.”

Those by-products include trichloramine, which can affect the respiratory system and lead to irritation of the skin and eyes, as well as cyanogen chloride, which has been used in the past as a chemical-warfare agent.

There isn’t enough chlorine or urine in a pool to produce quite that level of destruction, but what is there can still find its way into your body, so science just gave swimmers another reason to hold it until you can get out.

TIME Chemistry

Squid Protein: Our Best Defense Against Chemical Weapons?

A woman, affected by what activists say was a gas attack, receives treatment inside a makeshift hospital in Kfar Zeita village in Hama
A woman, affected by what activists say was a gas attack, receives treatment inside a makeshift hospital in Kfar Zeita village in the central Syria province of Hama on May 22, 2014. Reuters

If engineered correctly, the enzyme can "chew up" toxic agents in the human body

A team of researchers at the University of Tennessee at Knoxville has identified an enzyme produced in the bodies of squid that may be effective in breaking down nerve gasses and other deadly chemical weapons.

The team’s study, recently published in the Journal of Physical Chemistry, focused on engineering the improvement of these proteins — known as “bioscavengers” — that “chew up” nerve agents like sarin, a chemical infamous for its use as a weapon in the ongoing Syrian civil war and in a terrorist attack on the Tokyo subway in 1995.

The team aspires to create a prophylactic drug from these enzymes that will mitigate their harmful effects on humans, but first they must modify the enzymes to ensure that the human body won’t destroy them first.

“Using an enzyme from a squid as a bioscavenger in humans is problematic because the human body will recognize it as a foreign substance and chop it up,” said research team member Jerry Parks, adding that “other groups have already shown possible ways to get around that problem.”

TIME Chemistry

The ‘Godfather of Ecstasy’ Is Dead at 88

Alexander Shulgin, pharmacologist and chemist known for his creation of new psychoactive chemicals, ..
Alexander Shulgin, pharmacologist and chemist known for his creation of new psychoactive chemicals, is interviewed in Cambridge, Mass., on Dec. 1, 2005 Brian Snyder—Reuters

He introduced psychiatry to the medical potential of psychoactive chemicals, even as they attracted controversy elsewhere

Alexander Shulgin, the eccentric American scientist whose study of psychoactive chemicals inspired psychiatric research and gave wings to two generations of electronic-music apostles across the globe, died on Monday after a prolonged battle with illness. He was 88.

Shulgin, known as Sasha to his friends and as the Godfather of Ecstasy to just about everyone else, had a career that spanned more than half a century — he received his Ph.D. in biochemistry from the University of California, Berkeley, in 1954 — but gained most attention for his groundbreaking work on the chemical compound MDMA, popularly known as ecstasy.

The substance had first been synthesized and then forgotten by German scientists shortly after World War II, only to be rediscovered by Shulgin in 1976. Recognizing its powerful ability to lower inhibition and increase feelings of empathy — and thus its potential as a treatment for anxiety and other psychiatric disorders — he went to work perfecting it, and then championing its benefits.

The adverse effects of MDMA quickly ruled it out as a therapeutic tool, however, and instead the drug forged an intimate connection with dance music and modern rave culture. This reporter first learned about Shulgin while researching a 2013 story on MDMA and American electronic dance music. At that time, the drug was the subject of intense media scrutiny. Two college students had died at, or shortly after, the Electric Zoo music festival in New York City; the killer, several media outlets insisted, was a strange new drug called Molly (as MDMA came to be colloquially called in the U.S.).

For Shulgin, though, the chemical — and the 200 others he explored and synthesized in his backyard laboratory — was benign, even as three decades’ worth of critics insisted otherwise, and despite the drug’s linkage to scores of deaths around the world.

According to the psychedelic-research website Erowid, which broke the news of his death, Shulgin’s health had been on the decline since 2010, when he suffered a stroke.

TIME Appreciation

Google Doodle Honors Dorothy Hodgkin, Nobel-Prize Winning Chemist

She was famous for discovering the structure of organic molecules

Monday’s Google Doodle honors Dorothy Hodgkin, a Nobel-Prize winning British chemist who determined the 3-D molecular structures of some of our most important biomolecules, like penicillin, insulin and vitamin B12.

Hodgkin, who would have turned 104 on Monday, was best known for helping improve the techniques of X-Ray crystallography, a process which allows scientists to learn how molecules are put together and determine their three-dimensional structures. Previously, this method had mostly been used on inorganic molecules, but she and her mentor John Desmond Bernal were the first to use X-Ray crystallography to determine the structure of complex organic molecules like insulin and penicillin. She won the Nobel Prize in Chemistry in 1964 for her work in this area, and became only the third woman in history to win this prize.

Hodgkin was also heavily involved in humanitarian causes. She was the chair of the Pugwash Conference from 1976 to 1988, an organization inspired by a manifesto by Albert Einstein and Bertrand Russell that works to reduce harm and conflict caused by scientific discoveries (like nuclear weapons.)

She died in 1994.

TIME plants

Talking Tomatoes: Sick Plants Warn Their Neighbors

Chatterbox: tomato plants have a lot more to say than you'd think
Chatterbox: tomato plants have a lot more to say than you'd think John Burke; Getty Images

Chemical signaling allows healthy plants to defend themselves when a single neighbor is under attack—a result of communication among species that were always thought to be entirely mute

We tend to think of plants as basically inert—the furniture of the natural world. They don’t move, they don’t make sounds, they don’t seem to respond to anything—at least not very quickly. Grass doesn’t cry when you cut it, flowers don’t scream when they’re picked. But as is often the case, our human-centric view of the world misses quite a lot. Plants are talking to each other all the time. And the language is chemical.

Over the last few decades, a growing stream of papers has reported that different types of plants, from trees to tomatoes, release volatile compounds into the air for the benefit of neighboring plants. These chemical smoke signals come in many varieties, but their purpose seems to be to spread information about one plant’s disease or infestation so other plants can defend themselves. That’s been the general idea anyway, but exactly how plants receive and act on many of these signals is still mysterious. In this week’s Proceedings of the National Academy of Sciences, researchers in Japan offer some explanations, announcing that they’ve identified one such chemical message and traced it all the way from emission to action.

The experimenters looked at tomato plants infested by a common pest, the cutworm caterpillar. To start out, they grew plants in two plastic chambers connected by a tube, with an infested plant in the upwind chamber and an uninfested one downwind. When those downwind plants were later exposed to the cutworm pest, they defended themselves against it better than tomato plants that had not been exposed to a sick neighbor.

The researchers analyzed leaves from exposed and unexposed plants and found that out of the 8,226 compounds identified, only one showed up more frequently in the exposed plants, a substance called HexVic. And indeed, when the researchers fed HexVic to cutworms, it knocked down their survival rate by 17%.

Looking for the source of this protective substance, the scientists fingered a chemical precursor to HexVic among the cocktail of volatiles released by the infested plants. When they wafted it over uninfested plants, the plants began to produce HexVic, suggesting that they were turning the volatile into the caterpillar-killing chemical. A series of other tests confirmed that idea: Uninfested plants don’t have this precursor lying around, and must build their own weapon from the early warning message released by their infested relatives.

It’s an elegant tale, and it may be happening in far more plant species than tomatoes and with far more chemical signals that are still unintelligible to us. For now though, it’s hard not to have at least a little more respect for a type of life that not only communicates but, in its own invisible way, looks after its kin.

 

TIME Science

This Is How Caffeine Actually Affects Your Brain 

The science behind America's favorite drug

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Over 83 percent of Americans drink coffee, making the U.S. the world’s largest consumer of the potent beans. We probably love it so much because it’s also our favorite drug—caffeine keeps us going (even in today’s strangely wintry weather). But only a fraction of addicts actually understand how caffeine impacts the brain. Here’s a video that explains the addiction.

The Reactions video explores the chemistry of caffeine, which breaks up into three different molecules: theobromine, paraxanthine, and theophylline. The combined impact of these three compounds induces the wakeful state we all need to start our mornings.

TIME Appreciation

Google Doodle Honors Pioneering Black Chemist Percy Julian

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Dr. Percy Lavon Julian SCIENCE SOURCE—Getty Images/Photo Researchers RM

Today would have been Julian's 115th birthday

Today’s Google Doodle honors what would have been the 115th birthday of Percy Lavon Julian, a pioneering chemist who overcame the obstacles of segregation to ascend to international notoriety.

Julian, who died in 1975, was born in Montgomery, Ala. and graduated from DePauw University in Indiana. Julian synthesized chemicals from plants to make medicine, which included treatment for glaucoma and other inflammatory illnesses. He’s most well known for synthesizing male and female hormones from soybean oil and later creating a synthetic substitute for cortisone. His cortisone substitute was inexpensive, yet effective, and helped make the treatment for rheumatoid arthritis more accessible.

As an African-American, Julian was denied opportunities to work for large corporations throughout his career, though he went on to hold more 100 patents and received 19 honorary doctorates. In 1990, he was entered into the National Inventors Hall of Fame, and in 1993 he was honored with a Black Heritage Commemorative Stamp by the U.S. Postal service.

 

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