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Ordinary Glass with Extraordinary Properties Cloaks Your Cat

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<p>
  Nadia Drake, writing for Wired: ­
 </p>
<blockquote>
<p>
   Scientists in
   <a href="http://www.ntu.edu.sg/home/blzhang/">
    Singapore
   </a>
   and
   <a href="http://mypage.zju.edu.cn/en/hongshengchen">
    China
   </a>
   have crafted a cloaking device that works in natural light, and they’ve recorded videos of animals disappearing inside it.
  </p>
<p>
   This new device,
   <a href="http://arxiv.org/abs/1306.1780">
    described June 7
   </a>
   in a manuscript uploaded to arXiv.org, works by redirecting light waves around objects inside it. But unlike other recently described cloaking devices built from metamaterials — artificial materials with properties not found in nature — it’s made from a type of ordinary glass that bends and disperses light.
  </p>
</blockquote>
<p>
  The cloaking device uses six pieces of glass arranged in a hexagon to redirect light, which allowed the researchers to hide a fish from six different viewpoints. The researchers also made a device capable of hiding a cat from two angles. Since it’s made from more prosiac compoents, it’s likely to be cheaper than devices made of metamaterials.
 </p>
<p>
  The cloak itself isn’t invisible because of the shadows it casts, but with more tweaking, it could bring us closer to masking large objects and living creatures—the kind of thing we expect from
  <i>
   Harry Potter
  </i>
  , not reality.
 </p>
</section>

Seventy-five percent of honey sampled from around the world contained trace amounts of popular insecticides.

The Wave that Saves: The Warning Systems of Giant Honeybees

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<p>From Michael Marshall, reporting for New Scientist:</p>
<blockquote>
<p>If you’re at a sporting event and nothing much is happening, there’s a tried-and-tested way to pass the time: start a Mexican wave, also known simply as “The Wave”.</p><p>[…]</p><p>Giant honeybees also perform Mexican waves, but theirs have nothing to do with sport. They are a message to predators, the message in question being, “get lost”. Now it turns out the waves might also rock the bees’ nest, sending a warning message to all the bees simultaneously.</p>
</blockquote>
<p>Giant bees don’t live in hives, but on both sides of a flat comb, layered on top of each other. When “special agent” bees on one side of the nest sense a predator, they initiate the wave by sticking up their abdomen. Just like at a sporting event, the move quickly spreads from bee to bee.</p>
<p>The bees on the other side of the nest feel the vibrations from the synchronized wave and are warned of the danger. It may be the best evidence of “The Wave” truly supporting the team.</p>
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<p>When “special agent” bees on one side of the nest sense a predator, they initiate the wave by sticking up their abdomen.</p>

"BigBrain" a Small Step Toward Mapping Human Mind

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<p>
  Imagine taking a map of a city, shredding it into 7,400 pieces, and then putting it back together. You have to align the landmarks, fix any tear or rip you’ve created in the process, and make sense of any shred you might have lost.
 </p>
<p>
  Now imagine doing the same to a preserved human brain. That’s what scientists at the Institute of Neuroscience and Medicine in Jülich, Germany and the Montreal Neurological Institute in Canada did. It was a monumental undertaking, and one that will undoubtedly contribute to President Obama’s recently announced BRAIN Initiative, which stands for Brain Research through Advancing Innovative Neurotechnologies. But when compared with the lofty goals of BRAIN, BigBrain, as this project is called, is just a small step down a very long and uncertain road.
 </p>
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<img alt="" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/unloading-brain-slices.width-990_OaDTvyh.jpg"/>
<figcaption>Researchers slicing the chilled, preserved brain before staining begins.
        
    </figcaption>
</figure>
<p>
  BigBrain isn’t a part of the BRAIN Initiative, but it is precisely the kind of research that is needed to advance the multibillion-dollar, multiyear federal initiative toward its goal of mapping all the neurons in the human brain. The ambitious BRAIN Initiative is often compared with the Human Genome Project, a research program that had similarly lofty goals and a long timeline. It took the Human Genome Project 13 years to sequence our entire genome, and that’s after the project was officially started. The BRAIN Initiative is still in the planning phases, with timelines and specific goals still being formulated.  If anything, the work on BigBrain, detailed in this week’s issue of the journal
  <i>
   Science
  </i>
  , puts into perspective the enormity of the BRAIN Initiative.
 </p>
<p>
  As the name implies, BigBrain wasn’t a small side-project. Before it, most studies of its kind used the mouse brain, which is 7,500 times smaller than the human brain. Completing BigBrain took a team of scientists 10 years. They started by obtaining the brain of a healthy, 65-year-old woman who died of non-neurological reasons. Before they cut into it, they put the brain through an MRI scanner. That provided them with a reference—like the lid of a puzzle box—that they could use later when reassembling the brain. The team then sliced it into 20-micron sections. (By comparison, a human hair is about 70 microns thick, and a piece of paper is about 100 microns.) Alan Evans, one of the study’s authors, likened them to Saran wrap, except they didn’t come in a single roll but over 7,400 individual sections.
 </p>
<div class="cove-box flex-video" data-cove-id="2365029824" data-cove-params="&amp;topbar=false">
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<div class="inline-caption">
  Another historically famous brain belonged to a man called H.M. After he died, scientists sliced and stained his brain to learn about memory. For more about H.M. and memory,
  <a href="http://www.pbs.org/wgbh/nova/body/how-memory-works.html" target="_blank">
   watch the complete program
  </a>
  .
 </div>
<p>
  Next, they dyed each section to distinguish different cells, and then scanned the sections into the computer, a task that took 1,000 hours to complete. Once digitized, researchers repaired rips and distortions that occurred during slicing and scanning. Finally, they put the entire brain back together, slice by slice, using the MRI as a guide.
 </p>
<h2>
  Zooming In: A Map of Houses
 </h2>
<p>
  Prior to this study, MRI provided the most detailed 3D peek into a human brain. If you think of the brain as a map of a country, the resolution of MRI—about 1 millimeter—would make towns visible, but nothing smaller than that would be. BigBrain, on the other hand, “does 50 times better in each dimension than the typical 1-millimeter resolution of MRI,” says Katrin Amunts, a neuroscientist at the Institute of Neuroscience and Medicine in Jülich, Germany, and lead author of the paper. Specifically, BigBrain’s 20-micron resolution is fine enough to pick out individuals of certain types of cells, but not all; the smallest neurons in the brain are only about 10 microns across. Still, if this were a map, the level of detail provided by BigBrain greatly exceeds MRI, allowing us to see not just towns, but the houses within them.
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<img alt="" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/bigbrain.width-990_uzpTkUX.png"/>
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</figcaption>
</figure>
<p>
  “It’s an extension of the classic work that’s been done literally since the turn of 20
  <sup>
   th
  </sup>
  century to try to provide a more accurate description of the various areas of the brain and the morphology of the brain,” says Donald Stein, a neuroscientist at Emory University who was not involved with the work. Early in the 20
  <sup>
   th
  </sup>
  century, neuroscientists painstakingly surveyed the brain and documented what the cellular populations looked like, the various shapes, sizes, and groupings of different cells in different parts of the brain—a cul-de-sac of small houses here, large farmhouses scattered across a countryside over there. Certain regions of the brain, known as Brodmann’s areas, were later discovered to have specific functions, such as language, vision, or hearing. Today, BigBrain gives us a clearer picture of these areas.
 </p>
<p>
  But it’s still just one person’s brain, says Joshua Sanes, a neuroscientist at Harvard University and a member of the BRAIN Initiative advisory committee. He doubts that we will learn a whole lot by just looking at one sample. But he’s optimistic, explaining that BigBrain can be used as a reference to help ensure consistency across different studies and subjects. For example, a study comparing brains from healthy people with brains from Alzheimer’s patients would need to compare them to a standard reference brain in order to correct for the typical variability between subjects. Sanes hopes BigBrain will fulfill that role.
 </p>
<p>
  It can also serve as a scaffold, supporting data from other studies, just as the frame of a house supports siding and shingles. Currently, functional MRI can tell us which general region is involved in a function, like reading, but it doesn’t give us much more than a hazy outline. Other types of studies may use BigBrain to mark the location of different neurotransmitter receptors or patterns of gene expression. Allan Jones, the CEO of the Allen Brain Institute in Seattle and not an author on the paper, says BigBrain will be able to “anchor all of the great science being done in imaging to a much higher resolution atlas and framework.”
 </p>
<h2>
  Not So Fast: Life Without Streets
 </h2>
<p>
  Most scientists I interviewed agree this is a great start, but some still question whether BigBrain could live up to the hype surrounding its introduction. Stein likens BigBrain to “the high resolution screen on the latest iPhone. Is it really that much better than the last iteration that came out six months ago?”
 </p>
<p>
  Perhaps the biggest pieces missing from BigBrain are the connections between neurons and the different regions of the brain. Right now, BigBrain is like a map of a city with no streets, just buildings. While that sounds like a glaring oversight, Sanes says it’s a sensible approach; if researchers had tried to trace these physical connections by staining them, the brain would have emerged an inscrutable, tangled mess. To make the next step—understanding how neurons communicate and connect with each other—we’ll need additional studies that use different technologies. But even here, BigBrain can help. Michael Eisen, a biologist at the University of California at Berkley, suggests that we can begin to look at traffic patterns in the brain by overlaying other types of imaging onto the BigBrain atlas.
 </p>
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<img alt="" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/mgh_hcp_wedeen_lg-th.width-990_EDIkAjD.jpg"/>
<figcaption>Scientists hope to use BigBrain along with other data to help map connections between different regions of the brain.
        
    </figcaption>
</figure>
<p>
  “There are a lot of other equally valid approaches to understanding how the brain might work and [BigBrain] is just another one in the armamentarium that we should all be able to use and pick and choose from.” Stein says. Eisen agrees that BigBrain is one more tool in the chest. “Collectively, all these things are going to be important in moving the field forward, but any individual one of these things [isn’t] going to revolutionize the world.”
 </p>
<h2>
  Zooming Out: The Bigger Picture
 </h2>
<p>
  BigBrain is an early but important contributor to the BRAIN Initiative, Sanes says. This new paper, “reported one step on a very long path toward understanding the brain,” he says. “I think of it largely in terms of long-term goals. For example, this BRAIN Initiative.”
 </p>
<p>
  What the BRAIN Initiative hopes to accomplish is far beyond what neuroscience can do today. Currently, scientists can count the neurons of simple animals like worms and map some detailed circuits in mouse brains. Sanes suggests the early stages of the BRAIN Initiative will be similar to the Human Genome Project. When that research program began in 1990, genomes of smaller organisms like bacteria and worms had been sequenced, but the human genome remained a daunting and expensive task. The early stages of the genome project involved developing new technology that would ultimately make the rest of the undertaking much cheaper and easier, Sanes says.
 </p>
<p>
  Neuroscience is in much the same position today. Many technologies that will be needed to accomplish the BRAIN Initiative’s goals, like those behind BigBrain, are in their infancy. When the BRAIN Initiative begins next year, BigBrain will serve as a reminder of the difficulty of each step toward the ultimate goal.
 </p>
<p>
  Eisen, though, is optimistic. He predicts that we’ll see similar advances in the coming months. “This is very much a field in a dynamic moment in time,” he says. “This is what it looks like when a field is really humming.”
 </p>
</section>
<p>
 Photo credits: Amunts, Zilles, Evans, et al. and the NIH.
</p>

Earth-like Planets Found Orbiting Nearby Star

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<p>
  Lee Billings, writing for Scientific American:
 </p>
<blockquote>
<p>
   From its position 22 light-years away in the constellation of Scorpius, the red M dwarf star Gliese 667 C doesn’t look like much. Its dim light is lost to the naked eye, washed out by two brighter companion stars. Yet this tiny, exceedingly average star could play a crucial role in establishing that small, potentially Earth-like planets are common throughout our galaxy. Researchers have announced that seven planets orbit that star—and, if their mathematical analyses are correct, three of them could be habitable.
  </p>
</blockquote>
<p>
  Astronomers previously knew of two planets that circle Gliese 667C. One named Gliese 667C c is a super-Earth—a planet slightly larger than Earth but much smaller than Uranus, which is about 14.5 times the size of Earth—and resides in the habitable zone, the distance from the star where liquid water can exist on the planet’s surface.
 </p>
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<img alt="" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/gliese-667c-system.width-990_1qtf4nt.jpg"/>
<figcaption>Artist's impression of the view from Gliese 667C d, one of the recently discovered exoplanets.
        
    </figcaption>
</figure>
<p>
  But now they have identified three to five additional planets orbiting Gliese 667C, two of which are super-Earths (Gliese 667C f and Gliese 667C e) that may reside in the habitable zone. All but one of these orbit very close to Gliese 667C—about the distance between the Sun and Mercury. But because Gliese 667C is smaller than our sun, its habitable zone is closer.
 </p>
<p>
  Like other exoplanets, these newest were discovered by detecting the slight pull they have on their star as they orbit. Some scientists are skeptical of the data, citing the problems with trusting weak signals amongst noisy data. But others are excited about the possibilities, in part because this type of star system is the most common found in the Milky Way.
 </p>
</section>
<p>
 Photo credit: ESO/M. Kornmesser
</p>

If This City Could Talk

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<p>
  If these walls could talk, what would they say? Or for that matter, what would a street lamp post say, given the hundreds, even thousands of people that pass it every day? An interactive exhibit in Bristol, UK allows visitors to “talk” to objects and hear their stories. Keith Stuart, writing for the Guardian, explains the Hello Lamp Post project:
 </p>
<blockquote>
<p>
   This fascinating project encourages visitors and residents to communicate with street furniture like lamp posts, post boxes and bus stops by using the repair numbers found on these objects as SMS codes. Participants simply text the relevant number to a central server thereby ‘waking up’ the object, which will then ask a series of questions via text messaging. The next person to ‘sign in’ with that object can learn about previous replies, and the idea is, regular ‘conversations’ with the same objects will allow players to learn lots of stories about the hidden lives of the city’s population.
  </p>
</blockquote>
<p>
  It sounds like a city-wide “Internet of Things”—where everyday objects are connected to the internet so they can communicate with each other, enabling them to react intelligently to the world around them, like a sprinkler system that would turn off when rain is forecast. And that’s kind of the idea. The project won the Playable City Award—which was inspired by the idea of the Internet of Things—for the way it encourages tourists and residents to explore the city.
 </p>
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<img alt="hello lamp post" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/hello-lamp-post.width-990_QMzyDKq.jpg"/>
<figcaption>
</figcaption>
</figure>
<p>
  It’s more of a playful version of the Internet of Things than a useful one, but there is at least one aspect that shows the way to a practical, connected future: The unique identifiers Hello Lamp Post uses are existing codes given by the city to indicate which objects need repair. Today, texting hello to these codes will strike up a conversation. Stuart calls it “sort of a cross between a chat forum and an Artificial Intelligence conversation system – but one that can be accessed through sending text messages to a manhole cover.”
 </p>
</section>

Two of Pluto’s Moons Named After Public Vote

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<p>
  Nadia Drake, writing for Wired:
 </p>
<blockquote>
<p>
   Formerly known as P4 and P5, Pluto’s tiniest moons now have official names: Kerberos and Styx.
  </p>
<p>
   The names were among the top three selected by voters during a two-week polling period; they have just been approved by the International Astronomical Union’s official nomenclature committee.
  </p>
<p>
   Thus, from this day forward, the two tiniest of rocks orbiting the overgrown-snowball-formerly-known-as-a-planet will conjure the tales of a three-headed dog guarding the gates of the underworld (Kerberos), and the river that doomed souls must cross (Styx).
  </p>
</blockquote>
<p>
  The votes didn’t come without celebrity endorsements. In February, when voting began, William Shatner suggested Vulcan as one of the names. Vulcan won handily, with over 170,000 votes. Second place went to Cerberus with more than 99,000 votes.
 </p>
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<img alt="" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/plutos-moons.width-990_FPB6M1K.jpg"/>
<figcaption>The Hubble Space Telescope has discovered five moons orbiting Pluto. The latest, previously known as P4 and P5, were named Kerberos and Styx, respectively.
        
    </figcaption>
</figure>
<p>
  But the process wasn’t entirely democratic. The International Astronomical Union (IAU) has to approve the names and took issue with Vulcan, saying too many other objects had that name. Second place Cerberus, which is also the name of an asteroid, was rejected, too. Mark Showater, who discovered P4 and P5, suggested the Greek spelling of Cerberus, Kerberos, an alternative which the committee found more palatable. Third place, Styx, took the remaining spot.
 </p>
</section>

Saving Sea Creatures By Removing Ghost Nets

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<p>
  Ashley Ahearn, reporting for the World, discusses ghost nets—lost or abandoned fishing nets that entangle and kill the ocean’s creatures.
 </p>
<blockquote>
<p>
   Here in Puget Sound, Doug Monk leads ghost net removal operations for the Northwest Straits Foundation, which uses sonar to find ghost nets and then sends divers down to remove them.
  </p>
<p>
   “We’ve pulled nets that have 50-60 birds in them, 1,200 crabs,” says Monk, who’s been a commercial diver on the Olympic Peninsula near Seattle for some 20 years, harvesting shellfish and sea cucumbers. For the past decade he’s also been fishing for ghost nets.
  </p>
</blockquote>
<figure class="richtext-image full-width">
<img alt="crab fishing line" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/crab-fishing-line.width-990_XDLPWyd.jpg"/>
<figcaption>A fisherman removes a fishing line from a crab before releasing it back to the sea.
        
    </figcaption>
</figure>
<p>
  Ghost nets unwittingly trap an unknown number of sea creatures—fish, crabs, starfish, dolphins, seals, and birds—every year. They amount to lost revenue for fishing and crabbing businesses, hurting the very industry responsible for leaving the nets. Numerous nonprofits, such as the Northwest Straits Foundation, have been established around the world to help tackle the problem. They remove existing nets and work with fisherman to prevent additional lost nets.
 </p>
<blockquote>
<p>
   As [Joan] Drinkwin [programs director of the Northwest Straits Foundation] watches another giant net being pulled from the deep onto the Bet Sea’s deck, she says fewer nets are lost each year in Puget Sound, which gives her hope.
  </p>
<p>
   “It’s one of the few really big problems that we can solve’” she says. “And we’re making a huge amount of progress.”
  </p>
</blockquote>
</section>
<p>
 Photo credit:
 <a href="http://www.flickr.com/photos/minicooper93402/4559233533/">
  minicooper93402
 </a>
</p>

Teal Burrell

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