Tag Archives: mit

The Bombardier Beetle Packs a Hot Machine Gun

Many beetles have defense mechanisms which involves foul chemicals squirting from their abdomens, but bombardier beetles have taken it to the next level. Researchers from MIT, the University of Arizona, and Brookhaven National Laboratory wanted to see how it works, so they studied the bombardier beetle and figured it out. The research is published in Science.

CHARLES HEDGCOCK, © WENDY MOORE

“Their defensive mechanism is highly effective,” Arndt says, making bombardier beetles “invulnerable to most vertebrates, and invertebrates”—except for a few very specialized predators that have developed countermeasures against the noxious spray.

It’s a pretty good life if you’re a bombardier beetle – you have almost no natural predators, you can survive on every continent except for Antarctica and if someone annoys you, you can just send a foul jet at them with remarkable precision. The liquid these beetles eject is called benzoquinone, and is actually a fairly common defensive agent among insects, Arndt says. But what makes bombardier beetles so special is that they can superheat it first, and then send it out in a pulsating jet. What’s more, they can aim it precisely well. The new, multidisciplinary study wanted to find out how they can do this.

“Understanding how these beetles produce – and survive – repetitive explosions could provide new design principles for technologies such as blast mitigation and propulsion,” said Wendy Moore, one of the lead authors of the study, from the University of Arizona.

The key is that they synthesize the chemical at the moment they want to use it, mixing two chemical precursors in a protective chamber in their hindquarters. As the two chemicals combine, they give out a lot of heat, which is absorbed by the jet. The process also generates the pressure needed to eject it, in a series of pulses.

“Twenty-five years ago, a team of scientists from Cornell University and MIT discovered that each blast from the bombardier beetle is actually a series of extraordinarily fast micro-pulses,” Moore said.


The new study found, which took X-Ray images of the beetles’ abdomens, revealed that the chemical is formed through a passive process, and not active muscle contraction, as was previously believed.

“By having a pulsed delivery, these small beetles produce a relatively large amount of defensive spray, which they can aim precisely and with great force and speed,” Moore said. “This is truly one of the most remarkable and elegant defensive mechanisms documented to date,” she added.

Understanding the beetles’ ability to create these violent processes and survive them is not only interesting in itself, but may lead to the design of new blast-protection systems; this study shows how the sophisticated and specialized biological design of the system works to simultaneously achieve defensive and protective functions. It’s also, as the researchers point out, one of the most elegant mechanisms in the natural world.

Journal Reference: Mechanistic origins of bombardier beetle (Brachinini) explosion-induced defensive spray pulsation www.sciencemag.org/lookup/doi/10.1126/science.1261166

Expanding Brain Samples to Better See Them

Researchers from the Massachusetts Institute of Technology (MIT) have found a way to enlarge and map brain samples. This inexpensive technique will now allow scientists to get a much closer look at the human brian and perhaps figure out some of its long standing secrets.

Using a new technique that allows them to enlarge brain tissue, MIT scientists created these images of neurons in the hippocampus.
Image: Fei Chen and Paul Tillberg

Ever since the 1500s when microscopes were first developed, people have wanted to zoom in more and more. But scientists working at MIT decided to take a different approach, and instead of zooming in with the microscope, they simply made the samples bigger. Of course, that’s nowhere near as easy as it sounds. They did this by embedding samples in a polymer that swells when water is added. This allows specimens to be physically magnified, and therefore imaged at a much higher resolution.

What makes this technique even more interesting is the fact that it uses relatively cheap materials. The chemicals and materials required are commonly available everywhere.

“Instead of acquiring a new microscope to take images with nanoscale resolution, you can take the images on a regular microscope. You physically make the sample bigger, rather than trying to magnify the rays of light that are emitted by the sample,” says Ed Boyden, an associate professor of biological engineering and brain and cognitive sciences at MIT.


The thing is, with conventional microscopes, there is a physical limit to how much you can magnify. Microscopes use lenses to focus light emitted from a sample into a magnified image. However, when you get to things which are comparable in size to the wavelength of light, things start to get tricky – and you actually can’t magnify things smaller than that wavelength. When scientists do want to image at this level, they use electron microscopes. This is a big problem.

“Unfortunately, in biology that’s right where things get interesting,” says Boyden, who is a member of MIT’s Media Lab and McGovern Institute for Brain Research. Protein complexes, molecules that transport payloads in and out of cells, and other cellular activities are all organized at the nanoscale.

Scientists have tried several approaches to get past this limit, but this is the first time the sample was focused, instead of the microscopy technique. The idea is to embed samples in an expandable polymer gel made of polyacrylate, a very absorbent material found in many common products, such as diapers.

“Once the tissue is labeled, the researchers add the precursor to the polyacrylate gel and heat it to form the gel. They then digest the proteins that hold the specimen together, allowing it to expand uniformly. The specimen is then washed in salt-free water to induce a 100-fold expansion in volume. Even though the proteins have been broken apart, the original location of each fluorescent label stays the same relative to the overall structure of the tissue because it is anchored to the polyacrylate gel”, MIT’s press room writes.

In a different study, MIT neuroscientists used calcium imaging to label these pyramidal cells in the brain. Image: Qian Chen

Using this technique, researchers managed to image a section of brain tissue 500 by 200 by 100 microns with a standard confocal microscope. Imaging such large samples would not be feasible with other super-resolution techniques, which require minutes to image a tissue slice only 1 micron thick. The resolution wasn’t diminished in any way either, which makes it even more spectacular.

“The exciting part is that this approach can acquire data at the same high speed per pixel as conventional microscopy, contrary to most other methods that beat the diffraction limit for microscopy, which can be 1,000 times slower per pixel,” says George Church, a professor of genetics at Harvard Medical School who was not part of the research team.

According to their study, this is the only way to truly analyze such samples.

“The other methods currently have better resolution, but are harder to use, or slower,” Tillberg says. “The benefits of our method are the ease of use and, more importantly, compatibility with large volumes, which is challenging with existing technologies.”

Source: MIT.

 

Meteorites Not Responsible For Building Solar System, Study Finds

For decades, astronomers have believed that meteorites are the building blocks of our solar system – the lego blocks for planets. But a new study from scientists at MIT and Purdue University suggests that this may not be the case after all – and we’ve given meteorites too much credit.

meteorite

An artist’s rendering of a protoplanetary impact. Early in the impact, molten jetted material is ejected at a high velocity and breaks up to form chondrules, the millimeter-scale, formerly molten droplets found in most meteorites. These droplets cool and solidify over hours to days.
Credit: NASA/California Institute of Technology

Meteorites are solid pieces of debris  asteroids or comets, that originate in outer space and survive the impact with the Earth’s surface. The name meteorite is typically used when the object enters Earth’s atmosphere and survives the fall and the crash to the Earth’s surface. If it doesn’t enter our planet’s atmosphere, the strictly correct term is meteoroid.This new study, based on computer simulations, concluded that there’s no way meteorites could have been the building blocks of planets. Instead, the research concluded that meteorites are just debris resulting from proto-planetary collisions during the early days of the Solar System. If this is true, then studying meteorites won’t yield information about how the planets were like in their early stages, as was previously believed.

“This tells us that meteorites aren’t actually representative of the material that formed planets – they’re these smaller fractions of material that are the byproduct of planet formation,” says Brandon Johnson of MIT’s Earth, Atmospheric and Planetary Sciences department. “But it also tells us the early solar system was more violent than we expected: You had these massive sprays of molten material getting ejected out from these really big impacts. It’s an extreme process.”

Johnson and his colleagues, including Maria Zuber, the E.A. Griswold Professor of Geophysics and MIT’s vice president for research, have published their results this week in the journal Nature.

 

[Also Read: The Only Carving from a Meteorite]

Collision models indicate that astral bodies like our Moon (and others of similar sizes) likely formed way earlier than was previously believed, and way before chondrites formed. Chondrites are stony (non-metallic) meteorites that have not been modified due to melting or differentiation of the parent body.

“If this finding is correct, then it would suggest that chondrites are not good analogs for the building blocks of the Earth and other planets,” said University of Chicago Associate Professor of Planetary Science, Fred Ciesla. “Meteorites as a whole are still important clues about what processes occurred during the formation of the Solar System, but which ones are the best analogs for what the planets were made out of would change.”

If this finding is true, then we should reanalyze what we know about the early stages of the Solar System. Image via IOP.

If this is the case, then meteorites are in fact byproducts, and not building blocks, and we’ll have to revise what we think about the early stages of the solar system.

“Chondrules were long viewed as planetary building blocks,” Zuber notes. “It’s ironic that they now appear to be the remnants of early protoplanetary collisions.”

However, not all computer simulations are accurate, and this is going to need some confirmation before it is viewed as a fact, but it casts a big shadow over something which was regarded as a near certainty for the longest of time.

“This would be a major shift in how people think about our solar system,” says Ciesla, who did not contribute to the research. “If this finding is correct, then it would suggest that chondrites are not good analogs for the building blocks of the Earth and other planets. Meteorites as a whole are still important clues about what processes occurred during the formation of the Solar System, but which ones are the best analogs for what the planets were made out of would change.”

Journal Reference:

  1. Brandon C. Johnson, David A. Minton, H. J. Melosh & Maria T. Zuber. Impact jetting as the origin of chondrules. Nature, 2014 DOI: 10.1038/nature14105

 

sugar water

Reactivating positive memories might fight depression [TED Talk]

Steve Ramirez and Xu Liu are two neuroscientists who are at the very forefront of their field. Their work is focused on mapping the memory system, but also on how memory activation alters neural pathways, thus changing our mood. For instance, the two spoke recently during a TED talk about their most impressive experiment yet where they used blue light to activate a fond memory in depressed mice. The mice were visibly in a better mood, suggesting that depression – a far more complex and difficult to treat mental disorder than most ‘healthy’ people think – can be dispelled using a similar method on humans, as well. Moreover, the changes caused an increase in the number of neurons, enforcing the idea that this kind of treatment actually gives results.

Switching depression off

Steve Ramirez and Xu Liu spend their days in a lab at MIT, working to manipulate the memories of mice. Image: TED

Steve Ramirez and Xu Liu spend their days in a lab at MIT, working to manipulate the memories of mice. Image: TED

I first heard about the MIT researchers when I wrote a piece about a breakthrough in neuroscience, describing how they found memories are stored in specific brain cells. A most impressive feat, but now it’s been taken to a whole new level. The team engineered a harmless virus that activates brain cells in mice when exposed to pulses of light. The virus acts as “a sort of light-sensitive switch that can be artificially installed in brain cells,” Ramirez says , “to activate or inactivate the brain cell simply by clicking it, and in this case we click it on with pulses of light.”

Last year, they demonstrated how pulses of light were used to trigger the memory of fear in a mouse not immediately facing any dangerous or fear-inducing situations, a memory that caused an otherwise calm and curious mouse to freeze in its tracks. This technique falls under an innovative field called optogenetics. Later, Ramirez and Liu attempted to induce positive memories and emotions.

The story of a depressed mouse

sugar water

Credit: TED

To detect those mice that were depressed, the team gave mice an option between sugar water and regular water. Those that were healthy showed a strong preference for the sweet water 80& of the time – a real treat! Some mice, however, chose the sugar water only 50% of the time. This probability equal to that of flipping a coin tells us that the mice couldn’t care less where they got their water as long as it quenched their thirst. This is a classic depression symptom: nothing seems to bring pleasure or attract you any way anymore.

But to use the same technique as previously demonstrated when fear was induced, the researchers had to know what memories a mice cherishes. It’s not like you can ask a mouse what’s their favorite, most fond memories though. Eventually, they locked in: male mice were happiest when they were put in a cage with a female. They activated this memory in mice with depression-like symptoms then offered them again the choice between sugared and normal water. Amazingly, the depressed mice chose the sugary water 80% of the time suggesting a complete success!

It’s been proven that depression inflicts physical changes to the brain. A depressed individual, human or otherwise, will have fewer neurons on a daily basis, whereas a normal, healthy individual will generate new neurons everyday. Obviously, this is a big problem. At the same time, this knowledge proved to be very useful since it acted as a proxy to see whether Ramirez and Liu actually changed something in the brain, on a physical level. Tests showed that not only did the depressed mice’s behavior changed, they also saw increased number of neurons. Double confirmation, checked.  When this happened, Ramirez recounts in the TED talk (which you should see, by the way!) likened the moment to a “double thick Oreo milkshake multiplied by world peace,”

 

 

eat cook grow

Book review: ‘Eat, Cook, Grow’

eat cook grow

“Eat, Cook, Grow: Mixing Human-Computer Interactions with Human-Food Interactions”
By Jaz Hee-jeong Choi (Editor), Marcus Foth (Editor), Greg Hearn (Editor)
MIT Press, 320pp | Buy on Amazon

Food is essential to survival and lies at the absolute bottom of our needs pyramid. You can’t make art or write a paper on an empty stomach. The critical step is to use food for sustenance, yet food can be tasty as we all know. Once you have your food supply secure, you begin to take other interests in food. You want to eat well – tasty and healthy – but you also want to share.  In the developed world – particularly contoured in urban environments – there’s a new paradigm to food consumption that’s beginning to take form: sustainable human-food interaction. What does this mean? Well, this was the scope of “Eat, Cook, Grow: Mixing Human-Computer Interactions with Human-Food Interactions” – a compelling book that explores how food intersects with our modern needs and how food interaction has changed (for good or worse) in today’s digital age.

The book, authored by more than two dozen scientists, is spread into three sections where research on the changing traditions and technologies involving food are described. “Eat” aims to remind us where our food comes from, discussing at great lengths about how sustainable farming is connecting to the urban environment, but also how digital platforms are challenging the norm of eating out. For instance, a project describes a “telematic” dinner party where guests join dinner parties remotely through a virtual presence. “Cook” is about innovative high tech cooking wear and dietary knowledge. Esther Toet, Bernt Meerbeek, and Jettie Hoonhout describe an amazing food behavioral system that seeks to correct poor eating habits. The authors turned kitchen utensils, crockery, and cutlery into smart sensing tools that time and notify you when you’re not eating healthy – all in real time. Finally, “Grow” push the boundaries of what we think of human-computer interfaces, relating these to growing as a special concern of food. In some chapters you’ll learn about exciting topics such as hyperculture – a sensor enabled (food tracking) polyculture that enables farmers and consumers to participate, share risks and decide what to grow.

“Eat, Cook, Grow” was compelling and made me think in different ways about how digital technologies are changing our interaction with food and drink in the coming years. Changing your plating shape and colour from the switch of a button, 3D printing food or smart nutrition are just a few of the exciting ideas we might see come to life. For certain, this isn’t your regular “cooking book”, although I was surprised to find a traditional food recipe at the end of each of the 15 chapters.

Featured Researchers: This Week in Science

We talk a lot about science and research, but we don’t spend enough time talking about the people who actually do the research. In case you haven’t followed our previous feature, here is where we share some of the most interesting studies from the week, and share a bit of information about the scientists who made them.

One third of fracking chemicals are of unknown toxicity

Article
Featured Researcher: William Stringfellow
Affiliantion: Lawrence Berkeley National Laboratory
Research Interests: The major focus of his research is the study of environmental biokinetics (the study of movements of or within organisms).  In an open system, the state of the microbial community is determined by the physical and chemical conditions of the environment and is rarely, if ever, limited by availability of microorganisms. The microorganism will grow until the limiting condition is met, whether it is nutrient availability, energy supply, toxicity, or physical parameters such as available surface for attachment or washout conditions.

Scientists find how lizards regenerate their tails

Scientific Paper
Article
Featured Researcher: Kenro Kusumi
Affiliation: Arizona State University
Research Interests: Kenro Kusumi studies development, regeneration, evolution and diseases of the spine. His research team explores what genes shape the vertebral column, how certain vertebrates such as lizards can regenerate their tails, how evolution has produced a diversity of spinal morphology, and how the inactivation of specific genes can lead to spinal diseases such as congenital scoliosis. They approach these questions by examining how genome information shapes development and adult function.

This bacterium shoots wires out of its body to power itself

Article
Featured Researcher: Mohamed El-Naggar
Affiliation: University of Southern California
Research Interests: Moh El-Naggar is a pioneer in studying energy conversion and charge transmission at the interface between living cells and synthetic surfaces. His work, which has important implications for cell physiology, may lead to the development of new hybrid materials and renewable energy technologies that combine the exquisite biochemical control of nature with the synthetic building blocks of nanotechnology.

How loud music damages your hearing

Martine-Hamann

Article
Featured Researcher: Martine Hamann
Affiliation: University of Leicester
Research Interests: “We are studying cellular mechanisms underlying tinnitus, using a combination of electrophsysiological, morphological and behavioural studies.  We seek to understand how nerve cells memorize an auditory trauma (neuronal plasticity) and aim to find biomarkers for pathogenic processes related to hearing loss and tinnitus.”

Hallucigenia revealed: the most surreal creature from the Cambrian

Scientific Paper
Article
Featured Researcher: Martin Smith
Affiliation: Cambridge University
Research Interests: “I am interested in the origin and establishment of the modern animal groups. My work includes the study of unusual organisms from Burgess Shale-type deposits and their microscopic counterparts, the Small Carbonaceous Fossils. I also have an interest in the phylogenetic techniques used to identify the affinity of these organisms, and in the preservation of these remarkable fossils.”

One single scrap car battery could be turned into solar cells that power 30 homes

Scientific Paper
Article
Featured Researcher: Angela Belcher
Affiliation: Massachusetts Institute of Technology
Research Interests: “The focus of our research is understanding and using the process by which Nature makes materials in order to design new hybrid organic-inorganic materials. Our research is very interdisciplinary in nature and brings together the fields of inorganic chemistry, materials chemistry, biochemistry, molecular biology and electrical engineering.”

100,000 elephants killed in Africa between 2010 and 2012

Article
Featured Researcher: George Wittemyer (donate to help fund his research here)
Affiliation: Colorado State University
Research Interests: George Wittemyer has dedicated his scientific career to research that is helping to combat poachers and conserve one of Earth’s most noble species – elephants. Wittemyer’s research is helping inform policymakers and potential ivory consumers around the world about the detrimental impacts of the illegal ivory trade on the elephant species, and he hopes the information from his findings will help stem ivory demand and prevent the continued decline of elephant populations.

Eating less meat could be the solution to water use
Scientific Paper: Eating less meat could be the solution to water use
Article
Featured Researcher: Mika Jalava
Affiliation: Aalto University
Research Interests: I couldn’t find much info about Mika Jalava, but I have contacted her in the hope that she will tell us a bit about herself.

All images taken from the researchers’ page.

Jibo-robot-helper

Meet Jibo, the family robot or the HAL 9000 you always wished for

Jibo-robot-helper

Designed by the world’s foremost social robotics expert, MIT’s Cynthia Breazeal, Jibo looks like a cross between HAL 9000 and Eve from Wall-E. The robot seeks to become the first in a line of truly intelligent robot helpers that not only assist the family with chores, but become part of it as well. Is this cute, crawling white desktop nothing more than parts and gears or will it genuinely reach its objective? This a debate I’d like you, the reader, to participate in.

Its makers market Jibo as not just a three axis motor or smart software – he’s part of the family! Manufactured emotions aside, Jibo’s hardware does indeed sound impressive, nevertheless. Only  11 inches (28cm) tall, with a 6-inch base, Jibo features a 5.7-inch 1980×1080 touchscreen, complete with stereo cameras, speakers and recorders. A social machine is nothing without dynamic software, and if you thought Siri was interesting, wait till you see what Jibo can do.

When Jibo's case is opened, he's programmed to say  “ow, you’re hurting me”.

When Jibo’s case is opened, he’s programmed to say “ow, you’re hurting me”.

 

It’s motion and face recognition algorithm allows Jibo to tell who you are and what you’re doing, then proactively help or entertain you. If Jibo is near you when you’re cooking supper, for instance, he’ll ask you if you need any more groceries and, if given the go, will place an order online for you or will help you with recipes.  It can also take family pictures and interact with its members, which it can recognize. Designed as a family bot to the greatest extent, Jibo can even tell bedtime stories in an interactive fashion that will delight children. The real caveat, in fact, lies in his ability to sustain a conversation. Unlike Siri, Jibo goes the extra mile and continues the discussion after you ask him a question or, more importantly, proactively initiates the conversation. Check out the presentation video below.

Who else finds this awkwardly creepy?

"Don't mind me, I'll be here if you need me"

“Don’t mind me, I’ll be here if you need me”

Is Jibo as cool as Breazeal and his makers would have us think? I can’t help remembering how Michio Kaku reported on a smart Japanese robot that, on video at least, was really smart, when in fact behind the scenes it would bump into people in all the wrong places and could only perform a series of strictly defined tasks – basically useless. Is Jibo the same? Maybe not. The fact that its makers have designed the software architecture using Linux and that there’s a developers’ SDK platform that programmers can use to enhance Jibo’s features and share these with other users makes Jibo much more robust. For instance, Jibo comes complete with storytelling functions, but you might be able to buy an app that helps the kids with homework and so on.

If Jibo is a success, it will most likely become the first in a series of family-helping robots. At the moment, it sells for $500 and you can order one by contributing to the official Indiegogo crowfunding campaign.

ZME readers, what’s your take on Jibo? Useless, genuinely innovative or downright scary? I’d love to hear your opinion.

jibo_robot

“Dishmaker”, which is about the size of a regular dishwasher, can make plates, cups and bowls in approximately one minute each, taking as much time to return the dish into its original circle-shaped raw material. “In 15 minutes you can have all the dishes you need for a family of four” – according to the MIT researchers involved. Photo courtesy: MIT.

A Fridge That Will Do Your Groceries For You?

Modern technology and the internet is now becoming a part of everyday kitchen appliances. And this is just the beginning.

Read on to see how your future kitchen will look like.

In the coming years it is a given that your home appliances will become smarter. This is a strange concept to grasp, but with the growth of the Internet into a realm where everything is connected and communicates, then it is a very real and exciting possibility.

Smart Appliances Are Already Among Us

If you have stayed a night in a modern hotel recently and have snuck something from the bar fridge, then you probably would have wondered how they knew exactly what you took without looking into the fridge. Well, these smart fridges, equipped with sensors that transmit their stock levels through the Internet, are just one of the few developments that are already reaching everyday kitchens.

Here are a few other advancements that you may or may not have already heard about:

  • Fridges automatically reordering from your local supermarket;
  • Pantries that suggest recipes based on what you have;
  • Spoons that tell the temperature, acidity and viscosity of your dish;
  • Soft kitchen sinks that don’t break dishes;
  • Oven timers based on your dish rather than time.

 

Technology To Change Your Habits

But these are just the tip of the iceberg, when it comes to our kitchens becoming smarter, the only thing that we can be sure of is that these advancements will start coming faster and more frequently than ever before – the technology literally is accelerating.

One of the leading institutions in this field is the Massachusetts Institute of Technology (MIT) ‘Counter Intelligence’ Team. Their mission statement is rather simple, to maintain the kitchen as the centre of the house, reversing the trend of choosing quick meals on the run rather than home cooking. With a focus on attaching internet connections to appliances, making utensils that can help you cook and installing sensors that will keep you safe from fire or poisons, you can see that they are truly pushing for the kitchen of the future.

One amazing new project is a machine named the Dishmaker, that builds your plates as and when you need them rather than stacking them in cupboards. This smart kitchen technology is already making its way from the Universities and research institutions through to the consumer.

“Dishmaker”, which is about the size of a regular dishwasher, can make plates, cups and bowls in approximately one minute each, taking as much time to return the dish into its original circle-shaped raw material. “In 15 minutes you can have all the dishes you need for a family of four” – according to the MIT researchers involved. Photo courtesy: MIT.

“Dishmaker”, which is about the size of a regular dishwasher, can make plates, cups and bowls in approximately one minute each, taking as much time to return the dish into its original circle-shaped raw material. “In 15 minutes you can have all the dishes you need for a family of four” – according to the MIT researchers involved. Photo courtesy: MIT.

Fridges that monitor the useful life of food, reorder staple items such as milk and clean themselves already available to purchase.

More Technology for Less Hassle

But what does all this mean for the consumer? How successful will these smart home appliances be among ordinary men?  Does it mean I now need an MIT Engineering degree just to cook dinner for two? Quite the opposite really, what this new technology will lead to is an easier and more enjoyable kitchen where chores are a thing of the past and more time can be spent on what you enjoy, cooking delicious food for family and friends.

Lozano holds a prototype of a microthruster, developed to propel small satellites in space. PHOTO: BRYCE VICKMARK

Next generation of tiny satellites could explore space propelled by ion thrusters

Lozano holds a prototype of a microthruster, developed to propel small satellites in space. PHOTO: BRYCE VICKMARK

Lozano holds a prototype of a microthruster, developed to propel small satellites in space. PHOTO: BRYCE VICKMARK

Paulo Lozano, of MIT’s Space Power and Propulsion Laboratory, is a space enthusiast for as long as he can remember, growing up with Carl Sagan’s Cosmos and spending much of his childhood in bookstores studying science and other worlds in our solar system. His passion and hard work eventually landed him a job at MIT where he has made great strides in revamping the university’s Propulsion Lab by focusing more on hardware, instead of the theoretical work mostly done during the lab’s early days.

Inside the lab, all sorts of bulky crafts can be found, like a 100 lbs. engine the kind used to generate thrust for today’s spacecraft to the moon, planets and far-off asteroids like Ceres and Vesta. Among all these massive and impressive hardware, it’s easy to miss what’s the maybe the most interesting out of the whole bunch. Amid a cluttered desk, lies Lozano’s favorite project – no larger and no heavier than a Lego brick, this device may represent the future of space exploration.

The device in question is a tiny ion thruster, the kind which will be used to cheaply and efficiently propel shoebox-sized satellites, known as “CubeSats.” These tiny satellites are really cheap to make, less than $10,000 launch cost included (piggy-bagging on more important cargo), but since they lack a propulsion system, the Cubesats eventually drift lower and lower into orbit until they enter the atmosphere and blast into pieces.

Paulo Lozano PHOTO: BRYCE VICKMARK

Paulo Lozano
PHOTO: BRYCE VICKMARK

Clearly, you can’t use a conventional propulsion system like a combustion engine or electric motor mounted on a 10x10x10 cm box. Ion thrusters, which can run on solar power, contain a small amount of liquid propellant that, when electrified, creates a stream of ions that are released from microscale nozzles as puffs of charged gas — generating a thrust that can propel a small satellite forward. These typically deliver low thrust at a very high efficiency (up to 55 times higher than a jet engine), and their compact size makes them an ideal solution.

What this means is that Cubesats of the future and large satellites alike won’t necessarily have their fate sealed once they reach low-orbit. Furthermore, ion thrusters offer the means not only to compensate orbit, but also move satellites further into space in a cheaply manner, albeit at  low velocities.

“The goal is to make [CubeSats] do most of the things we already do with big satellites, except in a less expensive way,” Lozano says. “People have very big plans for these very small spacecraft.”

“The price tag of exploration missions is too high,” Lozano says. “But imagine what would happen if you had these very small platforms. Instead of launching one, you could launch 20 for the same price. And you could do as exciting science as you could with the big ones, like go to Europa [a moon of Jupiter]. Why not? The sky is the limit.”

via MIT

A four-segment milli-motein chain with a one-centimeter module size. (Credit: MIT Center for Bits and Atoms)

Precursurs to real-life Transformers: tiny robots join together and fold into shapes

Scientists at MIT have created tiny, millimeter-scale robots inspired by proteins that join together and can fold into various shapes. Though the research is still in its incipient form, these tiny robots could pave the way for the first real-life Transformers.

A four-segment milli-motein chain with a one-centimeter module size. (Credit: MIT Center for Bits and Atoms)

A four-segment milli-motein chain with a one-centimeter module size.
(Credit: MIT Center for Bits and Atoms)

Appropriately called milli-moteins, the robots can’t shape into complex shapes like a car or spaceship. Actually, at first glance they might not like much. Though they might look like a common assortment of metal rings and strips – something you might find lying around in your workshop drawers – make no mistake, these tiny mechanized modules are complex and powerful.

“It’s effectively a one-dimensional robot that can be made in a continuous strip, without conventionally moving parts, and then folded into arbitrary shapes,” said Neil Gershenfeld, head of MIT’s Center for Bits and Atoms.

Designed based on watchmaking techniques and inspired by proteins’ natural folding ability, the milli-moteins join together to form the world’s smallest chain robot.

Though the research is funded by DARPA, the scientists do not have an immediate goal. Applications for such a smart system range from devices that change shape or swap materials to accommodate new environments to real-life Transformers, but the research is less aimed that solving a particular problem, as it is at exploring the milli-moteins potential.

“In the world field of programmable matter, this is very much like the early days of computers, where much of the research is so general that the common thinking is that there must be things that this is useful for,” said Ara Knaian, Ph.D., of MIT’s Center for Bits and Atoms. “Part of the research that we’re now involved with is to find that killer application for this.”

Re-configurable matter

Each of the tiny robots is powered by a special kind of motor, similar in working principle to giant electromagnets used in scrapyards to lift cars, that can hold its position firmly even with power switched off. The motor is comprised of a series of permanent magnets paired with electromagnets which are arranged in a circle and  drive a steel ring that’s situated around them. By switching between magnetic fields, the magnets ” do not take power in either the on or the off state, but only use power in the changing state,” using minimal energy overall, according to the researchers. The MIT team designed these motors from scratch.



“This result brings us closer to the idea of programmable matter — where computer programs and materials merge to form a new kind of matter whose shape and function can be programmed — not unlike biology,” said Hod Lipson, an engineering professor at Cornell University. “Many people are excited today to learn about 3D printing and its ability to fabricate any shape; Gershenfeld’s group is already thinking about the next episode, where we don’t just control the shape of objects, but also their behaviour.”

Though the shapes illustrated by the scientists may not seem very complex or intricate, like the letter “L”, the MIT scientists have shown after simulating a mathematical model that virtually any 3-D shape could be assembled by folding a sufficiently long string.

Devices of the future might re-assemble to meet new purposes

Currently the chain of robots assemble themselves sequentially, but the scientists are confident they can improve their design, such that the folding of the string could be made multiple joints at a time.  Ultimately, a reconfigurable robot should be “small, cheap, durable and strong,” Knaian says, adding that right now, “it’s not possible to get all of those.” Still, he points out, “Biology is the existence proof that it is possible.”

via MIT Newsroom

 

The orientation of 4,000 S-shaped units forms a metamaterial lens that focuses radio waves with extreme precision, and very little energy lost. (c) Dylan Erb

New metamaterial focuses radio waves with extreme precision similar to Star Wars’ Death Star

Researchers at MIT have created a new metamaterial that they used to fashion a concave lens capable of focusing radio waves with extreme precision. The result lens is extremely lightweight compared to its counterparts developed from conventional materials, and could see promising applications in satellite telecommunications and space exploration of distant stars.

In many ways metamaterials are supernatural, that’s because by definition it is a material artificially engineered by man to have properties that can never be encountered in nature. It’s  an extremely exciting field, since you’re basically building new, unique compounds and structures. The most interesting applications of metamaterials we’ve been granted to see comes in the form of invisibility cloaks and what’s commonly referred to as “super lenses” – extremely potent lenses that focus light beyond the range of optical microscopes to image objects at nanoscale detail.

Building the metamaterial lens

The latter is what MIT scientists have been going for with their negative refraction concave lens, which bends electromagnetic waves — in this case, radio waves — in exactly the opposite sense from which a normal concave lens would work. These properties are given off by the structure of the metamaterial, and how individual cells are arranged. In this case, the researchers built a blocky, S-shaped “unit cell” only a few millimeters wide whose shape refracts radio waves in particular directions – 4000 of these were arranged to form the concave negative refraction lens. Each of these cells only bends radio waves slightly, but together they focus the wave.

The orientation of 4,000 S-shaped units forms a metamaterial lens that focuses radio waves with extreme precision, and very little energy lost. (c) Dylan Erb

The orientation of 4,000 S-shaped units forms a metamaterial lens that focuses radio waves with extreme precision, and very little energy lost. (c) Dylan Erb

Isaac Ehrenberg, an MIT graduate student in mechanical engineering, shaped the lens via 3-D printing layer by intricate layer from a polymer solution. He then washed away any residue with a high-pressure water jet and coated each layer with a fine mist of copper to give the lens a conductive surface.

“There’s no solid block of any material in the periodic table which will generate this effect,” Ehrenberg says. “This device refracts radio waves like no other material found in nature.”

In an experiment, two radio antennas were positioned between the metamaterial lens. The resulting energy transmitted through it was found to travel through the lens almost in its entirety, with very little being lost with the metamaterial- significant improvement in energy efficiency when compared with past negative-refraction design. The team also found that radio waves converged in front of the lens at a very specific point, creating a tight, focused beam.

Star Wars’ Death Star laser beam?

As an analogy, Ehrenberg sees the design and functionality of the lens much in the same way as the Death Star’s concave dish that focuses a powerful laser beam to destroy nearby planets in the movie Star Wars. Again George Lucas’ awesome saga offers invaluable inspiration to scientists.

Since it weighs less than a pound, the lens could be used to focus radio waves precisely on molecules to create the same high-resolution images currently produced by very heavy and bulky lenses. Mass is one of the main factors taken into account for space applications, and future space satellites would definitely benefit from this. In addition, Ehrenberg says its fabrication is simple and easily replicated, allowing other scientists to investigate 3-D metamaterial designs.

“You can really fully explore the space of metamaterials,” Ehrenberg says. “There’s a whole other dimension that now people will be able to look into.”

His findings were documented in the Journal of Applied Physics.

source

 

Nanomaterials to prevent speeding bullets

New tests conducted by MIT researchers working at the Institute for Soldier Nanotechnologies showed nanomaterials could lead to better armor against pretty much everything, from all sort of bullets to micrometeorites.

Go small to go big

In the good old days, if you wanted a good armor, you had to bulk up. First it was studded leather, then chainmail, steel and so on. But modern research has showed us that it’s not only heavy materials that get the job done; lighter materials, such as kevlar can get the job done even better. This new study pushed things even further, showing that much lighter materials are capable of doing the job just as effectively, or even better.

The key here is to use two or more materials whose stiffness and flexibility are structured in very specific ways – which is obtained by alternating layers just a few nanometers thick. In order to test their new materials, the team produced miniature bullets and measured the effectiveness of the impact absorbing material.

Good Results

The team developed a self-assembling polymer with a cake-like structure: alternating between rubbery layers, which provide resilience, and glassy layers, which were brittle but offered strength. Then they developed a method of shooting out high speed projectiles at the armor. The projectiles measured about 1/1000 of a millimeter, but they were big enough to simulate bullets, and small enough for the impact effects to be measured with an electronic microscope.

The team found that direction was quite important; a head on impact was absorbed more efficiently (by 30 percent) than an edgy impact. But all in all, the materials worked out even better than expected.

“The key to developing materials with better impact resistance is to understand deformation and failure behavior at the tip of an advancing projectile,” sayd Donald Shockey, director of the Center for Fracture Physics at SRI International, a nonprofit research institute in Menlo Park, Calif. “We need to be able to see that.”

Scientists and soldiers

This research could protect astronauts and shuttles from micrometeorites

The research was funded by the U.S. Army Research Office, and it’s easy to understand why the military would be interested in this kind of research.

“It’s a novel and useful approach that will provide needed understanding of the mechanisms governing how a projectile penetrates protective vests and helmets.”, Shockey explained. He adds that these results “provide the data required to develop and validate computational models” to predict the behavior of impact-protection materials and to develop new, improved materials.

This kind of approach hasn’t really been studied in depth until now, and MIT and Rice researchers working on the project weren’t thinking only about creating an armor; these nanomaterials could have a swarm of applications in different fields; they could be extremely useful for space shuttles, creating a coating which will protect them from micrometeorites, or for protecting jet engine turbine blade from high speed sand or ice particles.

Via MIT

Research was published in Nature

MIT scientists have devised a new technique for carbon nanotube sensors, as simple as etching on a sheet of paper. (c) Jan Schnorr

Carbon nanotubes drawn with a pencil render cheap and reliable sensors

Researchers at MIT have developed a novel technique of creating cheap and reliable sensors for toxic gases by simply etching carbon nanotubes with a mechanical pen on a special paper, fitted with electrodes. The method allows for easy to make, cheap and reliable sensors that detect noxious gases in the environment, without the hassle that usually follows carbon nanotube manufacturing.

MIT scientists have devised a new technique for carbon nanotube sensors, as simple as etching on a sheet of paper. (c) Jan Schnorr

MIT scientists have devised a new technique for carbon nanotube sensors, as simple as etching on a sheet of paper. (c) Jan Schnorr

Instead of graphite, MIT chemists developed a special pencil lead made out of compressed carbon nanotube powder, which can be used with any kind of mechanical pencil. A carbon nanotube is a tube shaped carbon molecule arranged in a hexagon lattice, only one nanometer in diameter or 50,000 times thinner than a human hair. Using the pencil,  Timothy Swager, the lead researcher, and colleagues, inscribed a sheet of paper, fitted with electrodes made out of gold. An electrical current was then applied to the sheet of paper, and measured as it flows through the carbon nanotube strip, now transmuted into a resistor.  Many gases bind to the carbon atoms in the carbon nanotubes, and thus disrupt electrical flow. By detecting this flow disruption, the presence of the gas can be determined.

For their research, the MIT scientists focused on detecting minute quantities of ammonia, a highly dangerous gas, but they claim the system can easily be adapted to a slew of gases. Two major advantages of the technique are that it is inexpensive and the “pencil lead” is extremely stable, says Swager. On top of that, conventional carbon nanotube sensors rely on hazardous manufacturing techniques likedissolving nanotubes in a solvent such as dichlorobenzene  – the present research  uses a solvent-free fabrication method.

“I can already think of many ways this technique can be extended to build carbon nanotube devices,” says Zhenan Bao, an associate professor of chemical engineering at Stanford University, who was not part of the research team. “Compared to other typical techniques, such as spin coating, dip coating or inkjet printing, I am impressed with the good reproducibility of sensing response they were able to get.”

The carbon nanotube sensor was described in the journal Angewandte Chemie

source: MIT

magnetic beads

Micro-beads based system could allow for instant laboratory analysis

magnetic beadsHarnessing the oscillation of magnetic microscopic beads, MIT scientists have carried out experiments which show that it’s possible to develop a tiny device capable of diagnosing biological samples instantly. Such a tiny lab would allow for fast, compact and versatile medical-testing.

Tiny magnetic balls, in the micrometer scale or a millionth of a meter, embedded with biomolecules such as antibodies, allow for proteins or even cells to bind to them. An oscillating magnetic field makes the individual beads resonate. Since the measured frequency is proportional to the mass of the bead+bio-sample, its size can also be determined. This would provide a way to detect exactly how much of a target biomolecule is present in a sample, and in the process also provide an instant information readout, compared to days typically required in a conventional laboratory. This could, for example, lead to tests for disease agents that would need just a tiny droplet of blood and could deliver results instantly, instead of requiring laboratory analysis.

Other chip-based biomedical tests are currently used today, but using this technique, coupled magnetic tracks on a microchip surface, the MIT researchers are confident that results can be provided a lot faster, and at a much smaller required biological sample size. However, the team has yet to prove their system with bio-samples, instead their system was proven to detect magnetic beads of different sizes, corresponding to those between particles that are bound to biological molecules and those that are not. The next obvious step after this proof of concept is repeating the procedure using biological samples, as well.

“It is very interesting how the researchers combine technologies that are well understood for applications in computing and data storage, and apply them to something completely different,” said R. Sooryakumar, a professor of physics at Ohio State University who was not involved in this research. He adds, “These magnetic devices are potentially valuable tools that could go well beyond how one may normally expect them to be used. The ramifications, for example in food safety and health care, such as pathogen or cancer detection, are indeed exciting.”

Findings were reported in the journal Lab on a Chip.

[source]

 

The permanently shadowed crater adjacent to the lunar south pole, called Shackleton, after the famous Antarctic explorer. Left elevation mapping, right digital photo of the crater. The structure of the crater's interior was revealed by a digital elevation model constructed from over 5 million elevation measurements from the Lunar Orbiter Laser Altimeter. (c) NASA

Signs of water ice found on one of the moon’s craters

The permanently shadowed crater adjacent to the lunar south pole, called Shackleton, after the famous Antarctic explorer. Left elevation mapping, right digital photo of the crater. The structure of the crater's interior was revealed by a digital elevation model constructed from over 5 million elevation measurements from the Lunar Orbiter Laser Altimeter. (c) NASA

The permanently shadowed crater adjacent to the lunar south pole, called Shackleton, after the famous Antarctic explorer. Left elevation mapping, right digital photo of the crater. The structure of the crater’s interior was revealed by a digital elevation model constructed from over 5 million elevation measurements from the Lunar Orbiter Laser Altimeter. (c) NASA

Scientists at MITBrown University, and NASA’s Goddard Space Flight Center may have come across an incredible discovery, after data from  the Lunar Reconnaissance Orbiter (LRO), a spacecraft which  orbits the Moon from pole to pole, suggests water ice might be present inside a massive crater, called the Shackleton crater.

The researchers used the spacecraft’s laser altimeter to illuminate the crater’s interior with infrared laser light, measuring how reflective it was. The surface of the crater absorbed some light, and reflected back the rest to the spacecraft, based on this, the scientists calculated the difference, and mapped out the relative brightness throughout the floor and walls of Shackleton crater.

“While the distribution of brightness was not exactly what we had expected, practically every measurement related to ice and other volatile compounds on the moon is surprising, given the cosmically cold temperatures inside its polar craters,” said the scientists.

Initial estimates hold some 20% of the crater’s surface covered in ice, which is 2 miles deep and more than 12 miles wide. However, the scientists warrant that the reflectance could be a due to a combination of ice and other minerals, or something else altogether.

“The reflectance could be indicative of something else in addition to or other than water ice,” said study lead author Maria Zuber, a geophysicist at the Massachusetts Institute of Technology. For instance, the crater floor might be reflective because it could have had relatively little exposure to solar and cosmic radiation that would have darkened it.

If there is indeed ice water present on the crater’s surface, how much is it? Well, for one, the laser allowed scientists to measure only a micron-thick portion of Shackleton Crater’s uppermost layer. Scientists note that ice might be located deeper. Researchers say the measurements showed this crater’s floor is much brighter than the floor of other nearby craters, suggesting there may be ice in it, but they added that they can’t be sure. Based on current data, researchers speculate there could be as much as 100 gallons of ice inside the crater.

“The next step will be to probe deeper beneath the surface to see if there is deeper water, and we intend to do this in the GRAIL extended mission,” said Zuber.

via redorbit

 

 

Brain power: harvesting power from the cerebrospinal fluid within the subarachnoid space. Inset at right: a micrograph of a prototype, showing the metal layers of the anode (central electrode) and cathode contact (outer ring) patterned on a silicon wafer. (Credit: Karolinska Institutet/Stanford University)

Brain glucose might power the future’s tiny medical implants

Brain power: harvesting power from the cerebrospinal fluid within the subarachnoid space. Inset at right: a micrograph of a prototype, showing the metal layers of the anode (central electrode) and cathode contact (outer ring) patterned on a silicon wafer. (Credit: Karolinska Institutet/Stanford University)

Brain power: harvesting power from the cerebrospinal fluid within the subarachnoid space. Inset at right: a micrograph of a prototype, showing the metal layers of the anode (central electrode) and cathode contact (outer ring) patterned on a silicon wafer. (Credit: Karolinska Institutet/Stanford University)

A team of researchers at MIT have successfully manage to fabric a fuel cell capable of running on glucose, which scientists envision will power highly efficient medical implants in the brain that can help paralyzed patients express motor functions again.  The outputted power is in the microwatt range, but despite its low range, scientists claim it’s just enough to fuel tiny devices.

A similar idea was expressed in the 1970s, when scientists demonstrated they could power a pacemaker which ran on a glucose powered fuel cell. The concept was soon abandoned in favor of the much more powerful lithium-ion batteries. These glucose fuel cells also used enzymes that proved to be impractical for long-term implantation in the body.

The MIT design uses a fuel cell on a silicon chip, the same technology used to make semiconductor electronic chips, with no biological components, allowing it to be integrated with other circuits that would be needed for a brain implant. The power conversion occurs due to  a clever platinum catalyst, a biocompatible material, which strips the electrons from glucose, mimicking enzyme activity that break down glucose to generate ATP – the energy of cells.  The researchers claim that the glucose fuel cell could get all the sugar it needs from the cerebrospinal fluid (CSF) that bathes the brain and protects it from banging into the skull.

Tests so far have shown that the fuel cell can generate power in the range of hundred of microwatts – quite enough to power ultra-low-power and clinically useful neural implant, according to the researchers. Scientists warrant, however, that we’re quite a few years from seeing this kind of technology applied in medical practice.

“It will be a few more years into the future before you see people with spinal-cord injuries receive such implantable systems in the context of standard medical care, but those are the sorts of devices you could envision powering from a glucose-based fuel cell,” says Benjamin Rapoport, a former graduate student in the Sarpeshkar lab and the first author on the new MIT study.

The findings were published in the journal PLoS ONE

via Kurzweil 

Stephen Quake

Prolific inventor, Stephen Quake, awarded the Lemelson-MIT $500,000 prize

Stephen Quake

Stephen Quake is a professor of bioengineering and applied physics at Stanford University and investigator at the Howard Hughes Medical Institute. Besides his fruitful academic background however, Quake is an extremely prolific inventor, as well, his most successful one being a chip with miniature pumps and valves that incorporates complex fluid-handling steps to speed genetic research. For his contribution to the field of genetics and innovative efforts combining integrated circuitry to biology, Quake was recently awarded the prestigious Lemelson-MIT prize for outstanding innovators, worth $500,000.

“I get interested in a scientific problem and often find a way to measure the thing I’m interested in,” Quake said in an interview. “Often I find the measurement technique has different applications.”

It’s not like he needs the cash that much, though. Quake co-founded Fluidigm Corp in 1999 to commercialize his genome sequencing technology, a company which  generated sales of $10.8 million in the first quarter of 2012.

Quake first reached major headlines in 2009, when news outlets covered how he managed to sequence his own genome for under $50,000. During his personal genome research, he found a mutation that made him prone to cardiomyopathy, a disease that weakens and enlarges the heart muscles. He soon choose to be frequently monitored by a cardiologist.

Imagine an age of personalized medicine, one in which every person would be able to have his genome sequenced, easy and on the cheap, to efficiently prevent genetically transmitted or favorable diseases. We might not be that far away. Last year I reported how Ion Torrent System developed a device which would be able to sequence a person’s genome for under $1000! That may sound fantasmagoric, but sources have it that it’s indeed double. More on it in 2013, alegedly.

Back to Quake, the inventor also developed a non-invasive prenatal diagnostic test for Down Syndrome and is currently preoccupied with better understanding the human immune system; an interested sparked when one of his two children developed food allergies.

“As we started to see doctors we realized a lot is not known about how allergies work and how the immune system gets off track,” he said.

When asked about the prize money for the recently awarded Lemelson-MIT, Quake said he’ll most likely put them in his kids’ college fund. Now that’s a guy cooler than all the video games put together.

To test their algorithm, the researchers designed and built a system of 'smart pebbles' — cubes about 10 millimeters to an edge, with processors and magnets built in. (c) M. Scott Brauer

‘Smart sand’ could morph into any object automatically

To test their algorithm, the researchers designed and built a system of 'smart pebbles' — cubes about 10 millimeters to an edge, with processors and magnets built in. (c) M. Scott Brauer

To test their algorithm, the researchers designed and built a system of ‘smart pebbles’ — cubes about 10 millimeters to an edge, with processors and magnets built in. (c) M. Scott Brauer

The Sandman would have certainly approve of the latest experimental tech to come off MIT. Researchers from the university have demonstrated how tiny computer pellets, just a few millimeters in size, were automatically bound together to form a simple 2-D shape. The same algorithm might be used in a future refined version which could allow this kind of “smart sand”, as its been dubbed, to self-sculpt itself into a complex, 3-D replica of an object that would’ve been subsequently immersed into the sand box.

MIT says that the equivalent example would be the starting steps of a sculptor – turning a block of stone into a final product. It basically works like this – small cube shaped pebbles, measuring 10 millimeters across the edges, are imbued with computing power and covered in magnets on all sides. These function as electropermanent magnets, which get switched on or off though a small electrical charge. An object that gets immersed into the a box filled with  “smart sand” has its edges delimited by its neighboring pebbles with which it is in contact. The shape of the object is the mirrored by cubes which activate the magnets and bind together in self-sculpting manner, while the other modules switch off.

The video below explains the algorithm which makes the ‘smart sand’ tick. The project is still in its infancy, and researchers hope to overcome the current challenges their facing, like drastically sizing down the pebbles while still retaining the same computing power, such that the improved models might allow highly complicated 3-D objects to get morphed. Also, the algorithm could be easily tweaked to allow multiple copies to be “sculpted”.

buckliball

Toy-inspired “Buckliball” paves the way towards a new class of engineering structures

buckliball

Scientist at MIT and Harvard University teamed up to figure out what would be the simplest 3-D structure capable of collapsing and morphing due to instability. Their inspiration came after the scientists came across a popular toy, spherical in shape and fitted with movable parts and hinges, which allows it to easily dimple in size reversibly. Based on this toy, the researchers created the  “buckliball,” a hollow, spherical object made of soft rubber with no movable parts, which can turn into a smaller ball, 46 percent its original size.

Its name was attributed since it resembles a buckyball, and because it makes us of the instability phenomenon known as buckling, most often in practice an effect which is sought to be avoided.

“In civil engineering, buckling is commonly associated with failure that must be avoided. For example, one typically wants to calculate the buckling criterion for columns and apply an additional safety factor, to ensure that a building stands, says  Pedro Reis, the Esther and Harold E. Edgerton Assistant Professor of Civil and Environmental Engineering and Mechanical Engineering at MIT. “We are trying to change this paradigm by turning failure into functionality in soft mechanical structures. For us, the buckliball is the first such object, but there will be many others.”

The buckliball has 24 special dimples arranged in a specific pattern for optimal buckling, which was induced by researchers by sucking the air of the buckliball with a syringe. When its thing ligaments buckle, the thicker ligaments rows undergo a series of movements the researchers refer to as a “cooperative buckling cascade.” Some of these thick ligaments rotate clockwise, while other counterclockwise, but interestingly they all come together harmoniously. Thus, the buckliball morphs from a circular structure into a rhombicuboctahedron at about half of its original size.


Morphable structures which make us of predictable buckling such as the buckyball have a range of application where they might be effectively used, be it on the micro or macro scale – a football stadium with an easily collapsible buckly dome; tiny drug-delivery capsules or soft movable joints requiring no mechanical pieces.

“The buckliball not only opens avenues for the design of foldable structures over a wide range of length scales, but may also be used as a building block for creating new materials with unusual properties, capable of dramatic contraction in all directions,” says Katia Bertoldi, an assistant professor in applied mechanics at Harvard.

The findings were published in the journal Proceedings of the National Academy of Sciences.

[source MIT]

An image of a transgenic mouse hippocampus.

Memories are stored in specific brain cells, MIT Inception-like research finds

An image of a transgenic mouse hippocampus.

An image of a transgenic mouse hippocampus.

When the brain deems an experience meaningful enough, it will transfer that information from short-term storage, where typically information like where you put your car keys or the phone number of a person you just met gets stored temporarily, to your long-term memory, offering the possibility to be accessed at a later time. Neurologists claim this recording is made in the brain by strengthening the connections between groups of neurons that participate in encoding the experience, a pattern of connections which is referred to as an engram. These engrams will typically stay dormant unless they’re stimulated by a cue, which will evoke the event back into memory.

This explains why a song playing in the background might instantly transport you back to a special event tied to the track or the sweet scent of a freshly baked pie might transport you back in time to when you were a child. There are a myriad of such “anchors” dispersed though out our neural network, however the existence of engrams beyond their hypothetical nature has been debated for a while, as their exact mechanism and location has been a focus of persistent research for many decades. Now, a recent research conducted by scientists at MIT which made use of optogenetics demonstrates that memories are indeed stored in specific brain cells.

“We demonstrate that behavior based on high-level cognition, such as the expression of a specific memory, can be generated in a mammal by highly specific physical activation of a specific small subpopulation of brain cells, in this case by light,” says Susumu Tonegawa, the Picower Professor of Biology and Neuroscience at MIT and lead author of the study reported online today in the journal Nature. “This is the rigorously designed 21st-century test of Canadian neurosurgeon Wilder Penfield’s early-1900s accidental observation suggesting that mind is based on matter.”

A breakthrough in neuroscience

Dr. Penfield is one of the most influential figures in neurosurgery, a pioneer in the field whose legacy includes, among others, the first maps of the sensory and motor cortices of the brain showing their connections to the various limbs and organs of the body, still used today, unaltered. He was a man inherently concerned with the various subterfuges of the human mind, and dedicated his life to understanding how the brain works and whether there is any scientific basis that might acknowledge the existence of the human soul. One of his most groundbreaking works is the elaboration of the Montreal Procedure, a controversial surgery in which he treated epilepsy patients by severing nerve cells in the brain where the seizures originated. The operation would take place under local-anesthesia, as the patient’s collaboration was deemed indispensable. Penfield would destroy only the affected nerve cells by the disease, as he stimulated the brain with tiny jolts of electricity and observed the patient’s response. While probing nerve cells in the hippocampus, the region of the brain responsible for memory formation and storage, some patients would report vivid and complex recollections of past events.

Many discussions followed around these sort of events, but until now, it wasn’t scientifically proven that the simple reactivation of nerve cells in the hippocampus could cause memory recall.

To test their hypothesis, the MIT researchers identified the particular brain cells in the hippocampus that were active only when a mouse was learning about a new environment. They then proceeded in identifying which genes were activated in those cells, and added the gene for channelrhodopsin-2 (ChR2), a light-activated protein used in optogenetic indispensable for the present research, to a genetically engineered mouse.

“We thought we could use this new technology to directly test the hypothesis about memory encoding and storage in a mimicry experiment,” says co-author Xu Liu, a postdoc in Tonegawa’s lab.

“We wanted to artificially activate a memory without the usual required sensory experience, which provides experimental evidence that even ephemeral phenomena, such as personal memories, reside in the physical machinery of the brain,” adds co-author Steve Ramirez, a graduate student in Tonegawa’s lab.

Inception: fear induced on command

The scientists next labelled a population of hippocampal dentate gyrus neurons, using tiny optical fibers to deliver pulses of light to the neurons. Finally, the mice were introduced to an environment and were left to accustom themselves for a few minutes of exploration. A mild food shock was induced all of sudden, which caused the mice to fear the particular environment. The brain cells activated during this fear conditioning became tagged with ChR2. Later, the mice were introduced in a totally different environment, with an obviously different maze and of another smell, and were left there to explore. A pulse of light was triggered onto the neurons involved in the first experience, which lead to the fear memory getting switched on; the mice quickly entered a defensive, immobile crouch. This is called fear conditioning.

“Our results show that memories really do reside in very specific brain cells,” Liu says, “and simply by reactivating these cells by physical means, such as light, an entire memory can be recalled.”

Activation of cells labelled in a context not associated with fear did not evoke freezing in mice that were previously fear conditioned in a different context, suggesting that light-induced fear memory recall is context specific.

“This remarkable work exhibits the power of combining the latest technologies to attack one of neurobiology’s central problems,” says Charles Stevens, a professor in the 
Molecular Neurobiology Laboratory at the Salk Institute who was not involved in this research. “Showing that the reactivation of those nerve cells that were active during learning can reproduce the learned behavior is surely a milestone.”

The method may also have applications in the study of neurodegenerative and neuropsychiatric disorders. “The more we know about the moving pieces that make up our brains,” Ramirez says, “the better equipped we are to figure out what happens when brain pieces break down.”

source