Contradictiontonature - Sapere Aude

- Carl Sagan, Cosmos.

(Giphy)

An excerpt from Time Magazines 10 Questions: Neil deGrasse Tyson.

(Time)

8 of the world’s most bizarre flowers:

1.) Swaddled Babies

2.) Flying Duck Orchid

3.) Hooker’s Lips Orchid

4.) Ballerina Orchid

5.) Monkey Orchid

6.) Naked Man Orchid

7.) Laughing Bumblebee Orchid

8.) White Egret Orchid

This year’s Halloween special wraps up the chemistry behind making a mummy: http://wp.me/p4aPLT-26m

(Image caption: Brandeis University professor Ricardo Godoy conducts the experiment in a village in the Bolivian rainforest. The participants were asked to rate the pleasantness of various sounds, and Godoy recorded their response. Credit: Alan Schultz)

Why we like the music we do

In Western styles of music, from classical to pop, some combinations of notes are generally considered more pleasant than others. To most of our ears, a chord of C and G, for example, sounds much more agreeable than the grating combination of C and F# (which has historically been known as the “devil in music”).

For decades, neuroscientists have pondered whether this preference is somehow hardwired into our brains. A new study from MIT and Brandeis University suggests that the answer is no.

In a study of more than 100 people belonging to a remote Amazonian tribe with little or no exposure to Western music, the researchers found that dissonant chords such as the combination of C and F# were rated just as likeable as “consonant” chords, which feature simple integer ratios between the acoustical frequencies of the two notes.

“This study suggests that preferences for consonance over dissonance depend on exposure to Western musical culture, and that the preference is not innate,” says Josh McDermott, the Frederick A. and Carole J. Middleton Assistant Professor of Neuroscience in the Department of Brain and Cognitive Sciences at MIT.

McDermott and Ricardo Godoy, a professor at Brandeis University, led the study, which appeared in Nature on July 13. Alan Schultz, an assistant professor of medical anthropology at Baylor University, and Eduardo Undurraga, a senior research associate at Brandeis’ Heller School for Social Policy and Management, are also authors of the paper.

Consonance and dissonance

For centuries, some scientists have hypothesized that the brain is wired to respond favorably to consonant chords such as the fifth (so-called because one of the notes is five notes higher than the other). Musicians in societies dating at least as far back as the ancient Greeks noticed that in the fifth and other consonant chords, the ratio of frequencies of the two notes is usually based on integers — in the case of the fifth, a ratio of 3:2. The combination of C and G is often called “the perfect fifth.”

Others believe that these preferences are culturally determined, as a result of exposure to music featuring consonant chords. This debate has been difficult to resolve, in large part because nowadays there are very few people in the world who are not familiar with Western music and its consonant chords.

“It’s pretty hard to find people who don’t have a lot of exposure to Western pop music due to its diffusion around the world,” McDermott says. “Most people hear a lot of Western music, and Western music has a lot of consonant chords in it. It’s thus been hard to rule out the possibility that we like consonance because that’s what we’re used to, but also hard to provide a definitive test.”

In 2010, Godoy, an anthropologist who has been studying an Amazonian tribe known as the Tsimane for many years, asked McDermott to collaborate on a study of how the Tsimane respond to music. Most of the Tsimane, a farming and foraging society of about 12,000 people, have very limited exposure to Western music.

“They vary a lot in how close they live to towns and urban centers,” Godoy says. “Among the folks who live very far, several days away, they don’t have too much contact with Western music.”

The Tsimane’s own music features both singing and instrumental performance, but usually by only one person at a time.

Dramatic differences

The researchers did two sets of studies, one in 2011 and one in 2015. In each study, they asked participants to rate how much they liked dissonant and consonant chords. The researchers also performed experiments to make sure that the participants could tell the difference between dissonant and consonant sounds, and found that they could.

The team performed the same tests with a group of Spanish-speaking Bolivians who live in a small town near the Tsimane, and residents of the Bolivian capital, La Paz. They also tested groups of American musicians and nonmusicians.

“What we found is the preference for consonance over dissonance varies dramatically across those five groups,” McDermott says. “In the Tsimane it’s undetectable, and in the two groups in Bolivia, there’s a statistically significant but small preference. In the American groups it’s quite a bit larger, and it’s bigger in the musicians than in the nonmusicians.”

When asked to rate nonmusical sounds such as laughter and gasps, the Tsimane showed similar responses to the other groups. They also showed the same dislike for a musical quality known as acoustic roughness.

The findings suggest that it is likely culture, and not a biological factor, that determines the common preference for consonant musical chords, says Brian Moore, a professor of psychology at Cambridge University, who was not involved in the study.

“Overall, the results of this exciting and well-designed study clearly suggest that the preference for certain musical intervals of those familiar with Western music depends on exposure to that music and not on an innate preference for certain frequency ratios,” Moore says.

Manufacturing Dopamine in the Brain with Gene Therapy

Parkinson’s patients who take the drug levodopa, or L-Dopa, are inevitably disappointed. At first, during a “honeymoon” period, their symptoms (which include tremors and balance problems) are brought under control. But over time the drug becomes less effective. They may also need ultrahigh doses, and some start spending hours a day in a state of near-frozen paralysis.

A biotech company called Voyager Therapeutics now thinks it can extend the effects of L-Dopa by using a surprising approach: gene therapy. The company, based in Cambridge, Massachusetts, is testing the idea in Parkinson’s patients who’ve agreed to undergo brain surgery and an injection of new DNA.

Parkinson’s occurs when dopamine-making neurons in the brain start dying, causing movement symptoms that afflicted boxing champ Muhammad Ali and actor Michael J. Fox, whose charitable foundation has helped pay for the development of Voyager’s experimental treatment.

The cause of Parkinson’s isn’t well understood, but the reason the drug wears off is. It’s because the brain also starts losing an enzyme known as aromatic L-amino acid decarboxylase, or AADC, that is needed to convert L-Dopa into dopamine.

Voyager’s strategy, which it has begun trying on patients in a small study, is to inject viruses carrying the gene for AADC into the brain, an approach it thinks can “turn back the clock” so that L-Dopa starts working again in advanced Parkinson’s patients as it did in their honeymoon periods.

Videos of patients before and after taking L-Dopa make it obvious why they’d want the drug to work at a lower dose. In the ‘off’ state, people move in slow motion. Touching one’s nose takes an effort. In an ‘on’ state, when the drug is working, they’re shaky, but not nearly so severely disabled.

“They do well at first but then respond very erratically to L-Dopa,” says Krystof Bankiewicz, the University of California scientist who came up with the gene-therapy plan and is a cofounder of Voyager. “This trial is to restore the enzyme and allow them to be awakened, or ‘on,’ for a longer period of time.”

Voyager was formed in 2013 and later went public, raising about $86 million. The company is part of a wave of biotechs that have been able to raise money for gene therapy, a technology that is starting to pay off: after three decades of research, a few products are reaching the market.

Unlike conventional drug studies, those involving gene therapy often come with very high expectations that the treatment will work. That’s because it corrects DNA errors for which the exact biological consequences are known. Genzyme, a unit of the European drug manufacturer Sanofi, paid Voyager $65 million and promised hundreds of millions more in order to sell any treatments it develops in Europe and Asia.

“We’re working with 60 years of dopamine pharmacology,” says Steven Paul, Voyager’s CEO, and formerly an executive at the drug giant Eli Lilly. “If we can get the gene to the right tissue at the right time, it would be surprising if it didn’t work.”

But those are big ifs. In fact, the concept for the Parkinson’s gene therapy dates to 1986, when Bankiewicz first determined that too little AADC was the reason L-Dopa stops working. He thought gene therapy might be a way to fix that, but it wasn’t until 20 years later that he was able to test the idea in 10 patients, in a study run by UCSF.

In that trial, Bankiewicz says, the gene delivery wasn’t as successful as anticipated. Not enough brain cells were updated with the new genetic information, which is shuttled into them by viruses injected into the brain. Patients seemed to improve, but not by much.

Even though the treatment didn’t work as planned, that early study highlighted one edge Voyager’s approach has over others. It is possible to tag AADC with a marker chemical, so doctors can actually see it working inside patients’ brains. In fact, ongoing production of the dopamine-making enzyme is still visible in the brains of the UCSF patients several years later.

It is possible to tag AADC with a marker chemical, so doctors can actually see it working inside patients’ brains. Image Source: MIT Technology Review.

In some past studies of gene therapy, by contrast, doctors had to wait until patients died to find out whether the treatment had been delivered correctly. “This is a one-and-done treatment,” says Paul. “And anatomically, it tells us if we got it in the right place.”

A new trial under way, this one being carried out by Voyager, is designed to get much higher levels of DNA into patients’ brains in hopes of achieving better results. To do that, Bankiewicz developed a system to inject the gene-laden viral particles through pressurized tubes while a patient lies inside an MRI scanner. That way, the surgeon can see the putamen, the brain region where the DNA is meant to end up, and make sure it’s covered by the treatment.

There are other gene therapies for Parkinson’s disease planned or in testing. A trial developed at the National Institutes of Health seeks to add a growth factor and regenerate cells. A European company, Oxford BioMedica, is trying to replace dopamine.

Altogether, as of this year, there were 48 clinical trials under way of gene or cell replacement in the brain and nervous system, according to the Alliance for Regenerative Medicine, a trade group. The nervous system is the fourth most common target for this style of experimental treatment, after cancer, heart disease, and infections.

Voyager’s staff is enthusiastic about a study participant they call “patient number 6,” whom they’ve been tracking for several months—ever since he got the treatment. Before the gene therapy, he was on a high dose of L-Dopa but still spent six hours a day in an “off” state. Now he’s off only two hours a day and takes less of the drug.

That patient got the highest dose of DNA yet, covering the largest brain area. That is part of what makes Voyager think higher doses should prove effective. “I believe that previous failure of gene-therapy trials in Parkinson’s was due to suboptimal delivery,” says Bankiewicz.

Image Credit: L.A. JOHNSON

Source: MIT Technology Review (by Antonio Regalado)

Using the Power of Space to Fight Cancer

From cancer research to DNA sequencing, the International Space Space is proving to be an ideal platform for medical research. But new techniques in fighting cancer are not confined to research on the space station. Increasingly, artificial intelligence is helping to “read” large datasets. And for the past 15 years, these big data techniques pioneered by our Jet Propulsion Laboratory have been revolutionizing biomedical research.

Microgravity Research on Space Station

On Earth, scientists have devised several laboratory methods to mimic normal cellular behavior, but none of them work exactly the way the body does. Beginning more than 40 years ago aboard Skylab and continuing today aboard the space station, we and our partners have conducted research in the microgravity of space.  In this environment, in vitro cells arrange themselves into three-dimensional groupings, or aggregates. These aggregates more closely resemble what actually occurs in the human body. Cells in microgravity also tend to clump together more easily, and they experience reduced fluid shear stress – a type of turbulence that can affect their behavior. The development of 3D structure and enhanced cell differentiation seen in microgravity may help scientists study cell behavior and cancer development in models that behave more like tissues in the human body.

In addition, using the distinctive microgravity environment aboard the station, researchers are making further advancements in cancer therapy. The process of microencapsulation was investigated aboard the space station in an effort to improve the Earth-based technology. Microencapsulation is a technique that creates tiny, liquid-filled, biodegradable micro-balloons that can serve as delivery systems for various compounds, including specific combinations of concentrated anti-tumor drugs. For decades, scientists and clinicians have looked for the best ways to deliver these micro-balloons, or microcapsules, directly to specific treatment sites within a cancer patient, a process that has the potential to revolutionize cancer treatment.

A team of scientists at Johnson Space Center used the station as a tool to advance an Earth-based microencapsulation system, known as the Microencapsulation Electrostatic Processing System-II (MEPS-II), as a way to make more effective microcapsules. The team leveraged fluid behavior in microgravity to develop a new technique for making these microcapsules that would be more effective on Earth. In space, microgravity brought together two liquids incapable of mixing on Earth (80 percent water and 20 percent oil) in such a way that spontaneously caused liquid-filled microcapsules to form as spherical, tiny, liquid-filled bubbles surrounded by a thin, semipermeable, outer membrane. After studying these microcapsules on Earth, the team was able to develop a system to make more of the space-like microcapsules on Earth and are now performing activities leading to FDA approval for use in cancer treatment.  

In addition, the ISS National Laboratory managed by the Center for the Advancement of Science in Space (CASIS) has also sponsored cancer-related investigations.  An example of that is an investigation conducted by the commercial company Eli Lilly that seeks to crystallize a human membrane protein involved in several types of cancer together with a compound that could serve as a drug to treat those cancers. 

“So many things change in 3-D, it’s mind-blowing – when you look at the function of the cell, how they present their proteins, how they activate genes, how they interact with other cells,” said Jeanne Becker, Ph.D., a cell biologist at Nano3D Biosciences in Houston and principal investigator for a study called Cellular Biotechnology Operations Support Systems: Evaluation of Ovarian Tumor Cell Growth and Gene Expression, also known as the CBOSS-1-Ovarian study. “The variable that you are most looking at here is gravity, and you can’t really take away gravity on Earth. You have to go where gravity is reduced.“ 

Crunching Big Data Using Space Knowledge

Our Jet Propulsion Laboratory often deals with measurements from a variety of sensors – say, cameras and mass spectrometers that are on our spacecraft. Both can be used to study a star, planet or similar target object. But it takes special software to recognize that readings from very different instruments relate to one another.

There’s a similar problem in cancer research, where readings from different biomedical tests or instruments require correlation with one another. For that to happen, data have to be standardized, and algorithms must be “taught” to know what they’re looking for.

Because space exploration and cancer research share a similar challenge in that they both must analyze large datasets to find meaning, JPL and the National Cancer Institute renewed their research partnership to continue developing methods in data science that originated in space exploration and are now supporting new cancer discoveries.

JPL’s methods are leading to the development of a single, searchable network of cancer data that researcher can work into techniques for the early diagnosis of cancer or cancer risk. In the time they’ve worked together, the two organizations’ efforts have led to the discovery of six new Food and Drug Administration-approved cancer biomarkers. These agency-approved biomarkers have been used in more than 1 million patient diagnostic tests worldwide.

NASA unveils greatest views of the aurorae ever, from space in HD

“When the free electrons finally find the ions they bind to, they drop down in energy, creating an incredible display of colorful possibilities. Of all of them, it’s the oxygen (mostly, with the strong emission line at 558 nanometers) and the nitrogen (secondary, with the smaller line at a slightly higher wavelength) that create the familiar, spectacular green color we most commonly associate with aurorae, but blues and reds — often at higher altitudes — are sometimes possible, too, with contributions from all three of the major atmospheric elements and their combinations.”

The northern (aurora borealis) and southern (aurora australis) lights are caused by a combination of three phenomena on our world, that make our aurorae unique among all worlds in our solar system:

Outbursts from the Sun that can go in any direction,

Our magnetic field, that funnels charged particles into circles around the poles,

And our atmospheric composition, that causes the colors and the displays we see.

Put all of these together and add in a 4k camera aboard the ISS, and you’ve got an outstanding recipe for the greatest aurora video ever composed. Here’s the in-depth science behind it, too.

The south side of Jupiter, observed by the Voyager 1 space probe on March 1, 1979.