lunes, 31 de diciembre de 2012

Neil deGrasse Tyson on Scientific Literacy, Education, and the Poetry of the Cosmos

ORIGINAL: Brain Pickings

Science is a way of equipping yourself with the tools to interpret what happens in front of you.

Neil deGrasse Tyson. Photo: Brain Pickings
People,lamented Richard Feynman in 1964,“I mean the average person, the great majority of people, the enormous majority of people — are woefully, pitifully, absolutely ignorant of the science of the world that they live in.” In the half-century since, we’ve sequenced the human genome, put a man on the moon and rovers on Mars, confirmed the existence of the Higgs “God particle” boson, and achieved innumerable scientific miracles, small and large, that enhance our daily lives in fundamental ways. And yet, bad science spreads, good science journalism is fighting an uphill battle against media reductionism and distortion, and the general public remains as just as woefully and pitifully distrustful of or, worse yet, unconcerned with science as in the Feynman days.

In this fantastic conversation with Stephen Colbert, Hayden Planetarium director Neil deGrasse Tyson — passionate crusader for space exploration, eloquent champion of the whimsy of the cosmos, modern-day Richard “Great Explainer” Feynmanbrings his characteristic blend of sharp insight, quick wit, and unapologetic opinion to the issue of scientific literacy and how it relates to everything from education to government spending to morality.

Highlights below, though the entire hour-long conversation — including the most brilliant and hilarious James Cameron Titanic critique you’ll ever hear — is more than worth the time.

On the ethics of discovery vs. the broader morality of application:
We are collectively part of a society that is using or not using, to its benefit or its detriment, the discoveries of science. And at the end of the day, a discovery itself is not moral — it’s our application of it that has to pass that test.

On the misunderstanding of science:
[Science] is distrusted not because of what it can do, but because people don’t understand how it does what it can do — and that absence of understanding, or misunderstanding, of the power of science is what makes people afraid. … Just because you don’t understand it, doesn’t mean it’s bad for you — go figure out how it works! That’s why we need a scientifically literate electorate — so that when you go to the polls, you can make an informed judgment and you can draw your own conclusions rather than tune into a particular TV station to have your conclusions handed to you.

On the poetry of astrophysics:
Some of the greatest poetry is revealing in the reader the beauty of something that is so simple you had taken it for granted. That, I think, is the job of the poet. The simplicity of the universe, if it doesn’t drive you to poetry it drives you tobask in the majesty of the cosmos.

Our academic system rewards people who know a lot of stuff and, generally, we call those people ‘smart.’ But at the end of the day, who do you want: The person who can figure stuff out that they’ve never seen before, or the person who can rabble off a bunch of facts?

A brilliant addition to history’s best definitions of science:
[Science] is a way of equipping yourself with the tools to interpret what happens in front of you.

On our broken yardsticks for assessing the value of scientific research:
Today, you hear people say, ‘Why are we spending money up there when we’ve got problems on Earth?’ And people don’t connect the time-delay between the frontier of scientific research and how it’s going to transform your life later down the line. All they want is a quarterly report that shows the part that comes out of it — that is so short-sighted that it’s the beginning of the end of your culture.

He goes on to point out that people grossly misperceive how much is actually being spent “up there,” assuming anywhere between 10 and 15% of taxpayer money, whereas the real number is a mere 6/10 of a penny on the tax dollar, or 0.6%. The solution:
The greatest need is to be able to have the foresight necessary to make investments on the frontier of science even if, at the time you make those investments, you cannot figure out how that might make you rich tomorrow.

Finally, when Colbert asks the grandest cosmic question of all — why there is something instead of nothing — Tyson answers with a brilliant haiku-esque retort that hints at the power of ignorance as a tool of science:
Words that make questions
May not be questions
At all

Tyson’s latest book, Space Chronicles: Facing the Ultimate Frontier (public library), is a must-read.

Brain Pickings has a free weekly newsletter and people say it’s cool. It comes out on Sundays and offers the week’s best articles. Here’s what to expect. Like? Sign up.

Carl Sagan's Cosmos














domingo, 30 de diciembre de 2012

20 Under 20 Begins. "Skip College and start changing the world"

Amazonía perdió 1.206 kilómetros cuadrados de selva

Diciembre 26, 2012

Vista de una de las áreas deforestadas e irrecuperables en la amazonia peruana. Foto: EFE

La Amazonía brasileña perdió un total de 1.206 kilómetros cuadrados de selvas entre los pasados agosto y noviembre, según un estudio basado en datos oficiales y divulgado hoy por una organización no gubernamental.

La medición fue realizada por el Instituto del Hombre y el Medio Ambiente de la Amazonía (Imazon), según imágenes de satélites del Gobierno, sostiene que la deforestación en el período analizado supera en un 129 % a la registrada entre agosto y noviembre de 2011, cuando desaparecieron 527 kilómetros cuadrados de selvas.

Heron Martins, investigador de Imazon responsable del trabajo, dijo que una de las causas recurrentes de estos aumentos de la tasa de deforestación es la actividad agropecuaria, pero indicó que, en algunas zonas, se ha comprobado que el desarrollo de grandes obras públicas contribuye a agravar la pérdida de cobertura vegetal.

En ese sentido, citó las obras para la construcción de cinco represas hidroeléctricas que están en pleno desarrollo en diversas regiones de la Amazonía brasileña.

También dijo que persisten las deficiencias de fiscalización de la actividad de madereras ilegales, que hasta han se han beneficiado con la construcción o asfaltado de diversas carreteras, sobre todo en el estado amazónico de Pará.

"El asfalto en sí no es el problema, pero obras de esa naturaleza sin la debida fiscalización acaban facilitando el acceso de aquellos que viven de la deforestación y la tala ilegal", afirmó Martins.

Indian Man Single-Handedly Plants 1,360 Acre Forest

ORIGINAL: Inhabitat
by Timon Singh

Subtropical forest in India photo from Shutterstock
Deforestation and desertification are critical problems in India that have led to barren land, increased soil erosion, decreased agricultural production, and devastated local wildlife. However one Indian man has made a stand – by single-handedly planting and cultivating a 1,360 acre forest that is home to a complex, thriving ecosystem.

Photo by gozef
Jadav “Molai” Payeng started his project 30 years ago when he was still a teenager. Then, in 1979, flood waters washed a large number of snakes ashore on the local sandbar in Jorhat, some 350 km from Guwahati. When the waters receded, Payneg (who was 16 at the time) noticed the reptiles had died due to a lack of forestry.

The snakes died in the heat, without any tree cover. I sat down and wept over their lifeless forms. It was carnage. I alerted the forest department and asked them if they could grow trees there. They said nothing would grow there. Instead, they asked me to try growing bamboo. It was painful, but I did it. There was nobody to help me. Nobody was interested,” said Payeng, who is now 47, to The Times of India.

Payeng chose to live on the sandbar, starting a life of isolation as he began work to create a new forest. Planting the seeds by hand, watering the plants in the morning and evening, and pruning them when required, he cultivated a huge natural reserve. After a few years, the sandbar was transformed into a bamboo thicket.

I then decided to grow proper trees. I collected and planted them. I also transported red ants from my village, and was stung many times. Red ants change the soil’s properties . That was an experience,” Payeng recalled.

Over the years, the reserve has seen a huge variety of flora and fauna blossom on the sandbar, including endangered animals like the one-horned rhino and Royal Bengal tiger. “After 12 years, we’ve seen vultures. Migratory birds, too, have started flocking here. Deer and cattle have attracted predators,” claims Payeng . Unfortunately, locals reportedly killed a rhino which was seen in his forest, something that Payeng clearly disapproves of. ”Nature has made a food chain; why can’t we stick to it? Who would protect these animals if we, as superior beings, start hunting them?

Amazingly, the Assam state forest department only learnt about Payeng’s forest in 2008 when a herd of some 100 wild elephants strayed into it after marauding through villages nearby. It was then that assistant conservator of forests Gunin Saikia met Payeng for the first time.

We were surprised to find such a dense forest on the sandbar. Locals, whose homes had been destroyed by the pachyderms, wanted to cut down the forest, but Payeng dared them to kill him instead. He treats the trees and animals like his own children. Seeing this, we, too, decided to pitch in,” says Saikia. “We’re amazed at Payeng. He has been at it for 30 years. Had he been in any other country, he would have been made a hero.

sábado, 29 de diciembre de 2012

Approval for gene-modified salmon spawns controversy

ORIGINAL: New Scientist
28 December 2012 

Fast-growing salmon have cleared another hurdle in an upstream battle to be the first genetically modified animal approved for human consumption. After a long and possibly politically motivated delay, federal regulators have released preliminary documents declaring the fish safe to eat and environmentally harmless.

Since 1995, a company called AquaBounty, based in Maynard, Massachusetts, has been seeking approval from the US government to sell its AquAdvantage fish. These Pacific salmon have been modified with a growth hormone gene from Chinook salmon, which causes them to grow twice as fast as normal fish.

Rather than releasing the fish into the wild, the company plans to engineer its eggs in highly secure tanks in Canada, then ship them to Panama to mature. As a precaution, the fish are all female and contain three copies of each chromosome rather than two, rendering them sterile.

Controversy has engulfed the fish since their creation, but the concern is more about their potential ecological impacts than dangers to human health. Organisations such as the Marine Fish Conservation Network, which promotes sustainable fishing practices, worry that the transgenic salmon could outcompete wild salmon if they escape. "The risk of escapes and damage to wild ocean fisheries is simply too great to be left to chance," director Matt Tinning said in a statement.

The organisation says it has not yet had time to review the newly released assessment, published on 27 December by the US Food and Drug Administration (FDA). In two preliminary documents, it declares that AquaBounty's safety measures are sufficient, that the fish would have no significant environmental impact and that they are safe for human consumption.

Delayed release
The timing of the release has sparked suspicion of political interference, as it came hours after a non-profit organisation called the Genetic Literacy Project published FDA documents showing that the assessment had been complete since April and should have been released immediately. The organisation's investigation suggests that the White House's Office of Science and Technology Policy (OSTP), concerned over the issue's sensitivity, had blocked the documents' release until after the presidential election.

Asked about the allegations, the OSTP referred New Scientist to the FDA, whose spokesperson Shelly Burgess declined to comment. But she says that the agency is being particularly cautious as the salmon are the first transgenic animal to reach this point in the approval process.

Final approval of the salmon could still be some way off, however. The public now has 60 days to comment on the documents before the FDA will review them again. Burgess says it is impossible to predict how long the next review might take.

Descubren en Siberia una bacteria que podría vivir en Marte

by +Verde
29 Dec 2012

Un equipo de científicos descubrió en el suelo permanentemente congelado siberiano bacterias capaces de vivir en un ambiente como el del planeta Marte, publicó esta semana a revista especializada Proceedings of the National Academy of Science (PNAS).

El hallazgo de los organismos que viven en condiciones hostiles se realizó en la península de Taimir, en el norte de Siberia, lugar donde expertos de la Universidad estadounidense de la Florida perforaron 40 metros de profundidad en el suelo helado.

Al analizar la arena cernida encontraron a las bacterias del género carnobacterium, una de las cuales fue resucitada en 2005 luego de permanecer congelada por 300 mil años. Los científicos lograron multiplicar estos microorganismos en laboratorio y los sometieron a un ambiente que reproducía las condiciones que tiene Marte.

Para sorpresa de los expertos dirigidos por Wayne L. Nicholson, los microorganismos pasaron con éxito la prueba, lo que constituye un estímulo para que los astrobiólogos busquen vida fuera de la Tierra.

Fuente: Prensa Latina, Agencias

Is Biomedical research really close to curing anything?

ORIGINAL: Science Dump
by Jur

A century ago, people would suffer and die from what we now consider routine bacterial infections. With the discovery of penicillin, a miracle occurred where it became possible to cure people who previously had been left for dead. We're now at the edge of a similar revolution due to remarkable innovations in the field of regenerative biology.

viernes, 28 de diciembre de 2012

SMART’ Teens Pair Up with TSRI Mentors

By Cindy Brauer

Staff Scientist Marc-Andre Elsliger shows robotics equipment to students from Murietta Mesa and Frances Parker high schools. (Photo by Jennifer Vela.)
Dressed in blue lab coats and safety glasses, 40 enthusiastic San Diego high school students toured laboratories, examined high-tech x-ray and electron microscopy equipment, and fired volleys of questions at researchers. These teenagers were participants in the recent Students Modeling A Research Topic (SMART) Team‘s Mentor Match Event hosted by The Scripps Research Institute (TSRI) California campus.

Now in its fifth year at TSRI, the community outreach initiative, which has been run jointly with the University of California, San Diego (UCSD) Super Computer Center, brings the reality of science directly to the students, according to Stephen Connelly, a staff scientist in the Wilson/Kelly labs. Connelly and Ange Mason of the Super Computer Center are coordinating this year’s San Diego SMART Team program.

Over the course of the academic year, SMART Teams work to complete a number of academic tasks in their groups before working with volunteer mentor scientists from TSRI on research projects that focus on understanding the structure-function relationship of a protein studied within the mentor’s lab. Trained in computer visualization software, the teams design and build 3D models of their proteins to help tell their specific research story. Finally, they create oral presentations explaining their work to a lay audience and a poster to present to a scientific audience.

With additional support from their high school teachers, who themselves received special training, and SMART program coordinators, students explore the molecular world and experience science as a process and not just a collection of facts, said Connelly.

The day-long Mentor Match Event, pairing teams with their research mentors, was organized as a “mini-science conference,” said Connelly, “with students squarely at the center of all the activity.” The student teams represented Francis Parker, El Capitan, Canyon Crest Academy and Murietta Mesa high schools.

TSRI Professor Ian Wilson, Hansen Professor of Structural Biology and long-time SMART Team supporter, provided one of the morning’s highlights as he shared thoughts on his life’s work in scientific research and recent developments in high-throughput structural biology.

The teens also got close-up views of the advanced crystallization robotics suite and the electro-microscopy suite during tours of the Joint Center for Structural Genomics and the Center for Integrative Molecular Biosciences at TSRI.

Following presentations on their proposed scientific projects, the SMART teams were “matched’ with TSRI mentor scientists. This year’s match-ups are:

  • Ryan Hoffman, research associate in the Ward lab, with El Capitan students, working on troponin, a protein that converts calcium fluctuation’s in the body into movement
  • Jintang Du, research fellow in the Gottesfeld lab, with the Canyon Crest Academy team, researching sirtuins, proteins that help regulate biologic pathways in bacteria.
  • Peter Lee, graduate student in the Wilson lab, with Francis Parker students, studying hemagglutinin, a protein found on the surface of influenza viruses
  • Daniel Murin, graduate student in the Sapphire/Ward labs, with Murietta Mesa students, working on a glycoprotein involved with the Ebola virus
  • Jessica Bruhn-Johannsen, graduate student in the Sapphire lab, with Murietta Mesa team members, studying the V protein, important in the body’s immune system response to viruses
Ronnie Fournier, an El Capitan ninth-grader summed up students’ response to the day’s activities. "It was the best science experience I could imagine having,” he said. “The scientists, labs tours and meeting everyone. No, really… it was amazing!"

UCSD, which is currently applying for funding for the program, will assume leadership of the San Diego SMART Team program next year. However, said Connelly, TSRI researchers will be able to continue serving as mentors.

The SMART Teams program has its roots in a 2008 partnership between the Milwaukee School of Engineering (MSOE) Center for BioMolecular Modeling (CBM) and the University of Wisconsin School of Medicine and Public Health, which then disseminated the SMART Team program to eight top research institutions across the United States. The San Diego program has received funding by the Howard Hughes Medical Institute, Biogen Idec, the National Institutes of Health and the National Science Foundation. Connelly also acknowledged Marisela Chevez, who helped establish and build the San Diego SMART Teams program; Professor Ian Wilson and Associate Professor David Goodsell for their continued support and assistance; and Dawn Eastmond, Nancy De Monte and Jennifer Vela who were especially helpful with the Mentor Match Event.

Pricing sunshine

ORIGINAL: The Economist
Dec 28th 2012

The rise of solar energy

SOLAR energy currently provides only a quarter of a percent of the planet’s electricity supply, but the industry is growing at staggering speed. Underlying this growth is a phenomenon that solar’s supporters call Swanson’s law, in imitation of Moore’s law of transistor cost. Moore’s law suggests that the size of transistors (and also their cost) halves every 18 months or so. Swanson’s law, named after Richard Swanson, the founder of SunPower, a big American solar-cell manufacturer, suggests that the cost of the photovoltaic cells needed to generate solar power falls by 20% with each doubling of global manufacturing capacity. The upshot is that the modules used to make solar-power plants now cost less than a dollar per watt of capacity. This means that in sunny regions such as California, photovoltaic power could already compete without subsidy with the more expensive parts of the traditional power market. Moreover, technological developments that have been proved in the laboratory but have not yet moved into the factory mean Swanson’s law still has many years to run. See full article.

Source: Bloomberg New Energy Finance

jueves, 27 de diciembre de 2012

Lake Ellsworth Antarctic drilling project called off

Analysis David Shukman Science editor, BBC News

The team burned much of its fuel in a bid to connect the under-ice boreholes

Related Stories

An ambitious mission to drill through 3km (1.8 miles) of Antarctic ice to a lake that has been sealed off for thousands of years has been cut short.

The team at Lake Ellsworth decided to call off the mission in the early hours of Christmas Day UK time.

They were unable to join the main borehole with a parallel hole that was to be used to recover drilling water.

The team is now "weatherising" the equipment and it is unclear when they will be able to resume the project.

The £8m ($13m) project, headed by the British Antarctic Survey (Bas), aimed to drill carefully down using near-boiling water to pierce the lake, which has been untouched for as much as half a million years.

The hope had been to find hints of simple life forms existing in the extreme conditions of pressure and temperature, and to find a record of climate in the lake's sediments.

Searching for life in the hidden waters of Lake Ellsworth was one of the most ambitious British science projects of recent years, so this failure in the drilling programme will come as a huge blow.

The team knew that the risks were high, but the idea of exploring an ancient and mysterious body of water isolated for hundreds of thousands of years had inspired passion and determination.

The challenge of designing and engineering equipment that could remain sterilised on the long journey to Antarctica, and then down through the 3km of ice-sheet, was immense and involved hundreds of people.

So the disappointment will be felt far beyond the 12 men at their remote camp on the ice. Engineers, technicians, support staff - and researchers eager for the results - will feel heavy disappointment. They may try again next year. But this was frontier science, a gamble, and it did not pay off.

The programme ran into trouble last week as the main boiler used to heat drilling water broke down, with a replacement part being flown from the UK reaching the remote site last Friday.

With the boiler working, the team aimed to make two parallel boreholes, intended to join 300m below the surface.

A first borehole was drilled and left for 12 hours to create a hot-water cavity. This was to be used to re-circulate drilling water and to balance pressures when the sequestered lake was finally breached.

However, the team were unable to reach the cavity during the course of drilling the second, main borehole.

"We kept trying for over 24 hours to reach that connection but we couldn't do it," said principal investigator of the project Martin Siegert, from the University of Bristol.

"All that time we were losing fuel and water from the ice sheet surface and we got to a critical condition where our calculations showed us we simply didn't have enough fuel to continue any further down into the ice sheet to hit the top of the lake," he told BBC News.

The team is now starting the long process of gathering up its equipment for eventual return to the UK, where it will be serviced.

Once back on UK soil, the team will have to develop a report on what went wrong, and only then can the thought of a return trip be considered.

"It will take a season or two to get all of our equipment out of Antarctica and back to the UK, so at a minimum we're looking at three to four, maybe five years I would have thought," Prof Siegert said.

But he remained hopeful about the future, and said that this year's mission was far from a complete loss.

"We still want to do that testing, they were compelling scientific drivers a few years ago and they remain so. It's very important that we take stock of what we achieved here," he said.

Given the long time that it may take to fund and mount another mission to Ellsworth, it may be that other nations aim for other sealed-off Antarctic lakes in the nearer term.

"We have never depicted it as a race, but it may well happen that others get there first," Audrey Stevens, Bas spokesperson, told BBC News.

More on This Story

Related Stories
Lake Ellsworth: Mission to the Antarctic's lost world19 DECEMBER 2012, SCIENCE & ENVIRONMENT
Antarctic lake bid set to restart21 DECEMBER 2012, SCIENCE & ENVIRONMENT
Antarctic lake drilling is halted17 DECEMBER 2012, SCIENCE & ENVIRONMENT
Images emerge from polar drilling13 DECEMBER 2012, SCIENCE & ENVIRONMENT

Kid Genius Saves Lives With New Cancer Screening Technology (VIDEO)

ORIGINAL: Addicting Info

 Jack Andraka
It is likely you know of someone who has had pancreatic cancer. It is one of the most common and lethal forms of cancer known to humankind. Pancreatic cancer typically gives no external symptoms until it has typically reached an advanced state, which results in the low survival rate for those diagnosed with it, with only a 6% survival rate after 5 years after diagnosis and treatment. Famous victims include astronaut Sally Ride, entrepreneur Steve Jobs, actor Patrick Swayze, and tenor Luciano Pavarotti; and that is only going back 5 years.

The opportunity to catch this deadly cancer early may have just arisen, thanks to a 15 year old boy named Jack Andraka, from Crownsville, Maryland. How it works he explains in his own words (from Crooks and Liars):

So, what I did; is create this paper sensor and it basically has single wall carbon nanotubes which are atom thick tubes of carbon mixed with anti-bodies to this one cancer bio-marker called mesothelin. An anti-body is basically a molecule that binds specifically to one other molecule. So, what happens is; when I compared it, to the current gold standard of protein detection called called ELISA (enzyme-linked immunosorbent assay), it was actually 168 times faster, over 26,000 times less expensive and over 400 times more sensitive. And what I found is that my sensor in a blind study it actually had a 100% correct diagnosis, in diagnosing pancreatic cancer and could diagnose the cancer before it actually became invasive.

I did not expect for it to be this good at detecting pancreatic cancer, anti-bodies and stuff so – I was blow away by how sensitive it was.

I actually got into this kind of work because my uncle he died due to pancreatic cancer it metastasized and I got interested in early diagnosis and I found the blood tests where the only practical way to detect it in routine screening, so then I got interested in mesothelin and actually loved single wall carbon nanotubes, they are the superheros of material science and so then I was just thinking how I could apply them here and it came to me one day in biology class.

I am incredibly excited, it’s like the Olympics of science fair, it’s amazing to be here, even if I don’t get a prize.

Of course, as humble as he was, he did, in fact win a prize. The grand prize in fact of the Intel International Science and Engineering Fair in the medical and health sciences category, as you can see here:

He is now a full on celebrity at his school, on par with any sports figure or rock star. Something well deserved for those who will not be given a fighting chance against the specter of pancreatic cancer.

He is now being featured in Smithsonian Magazine this month, including this video where you get to meet this boy genius, whom his mentor has called the Edison of our times:

And all of this before he even has a drivers license.

For those countless whose lives you will save, thanks to your research and innovation, we salute you Mr. Andraka. Thank you, for our friends, our family, ourselves.

Computing with Light

December 10, 2012

A breakthrough from IBM could signal a future for computing.

This image shows a falsely-colored integrated optical and electrical circuit. The blue wires carry optical signals and the yellow wires carry electrical ones.

IBM announced what it called a technological breakthrough today in San Francisco. The company verified in a manufacturing environment the feasibility of using light instead of electrical signals to transmit information. IBM had proven the concept of such technology, called “silicon nanophotonics,” back in 2010, but this announcement, following a decade of research, nudges the field towards commercial applications.

In its 2010 announcement, IBM described the invention succinctly: a chip that “integrates electrical and optical devices on the same piece of silicon, enabling computer chips to communicate using pulses of light (instead of electrical signals), resulting in smaller, faster and more power-efficient chips than is possible with conventional technologies.” The development forms a part of IBM’s Exascale computing program,” which wants to build a supercomputer than can perform a million trillion calculations (a so-called “Exaflop”) in a second. IBM says the chip was made using a 90 nanometer manufacturing process, and that the optical data can travel through the chip at 25 Gigabits per second.

Basically, IBM hopes this will solve the problem that we are creating and transmitting data faster than our hardware has been able to keep up with. Silicon nanophotonics, says IBM, will help industry “keep pace with increasing demands in chip performance and computing power. As one of the researchers, Dr. Solomon Assefa, explained: “For our computer servers to keep up with this growth, so that we can actually make sense of the data through analytics and so forth, we need to have a new technology.

Why compute with light, rather than electrons? As TR explained in 2011 (see “Light Chips”): “The speed of supercomputers is constrained not by processing power but by limits on how fast data can travel down the electrical wires that link up different chips. Light signals move significantly faster than electrical ones, so using them could remove that bottleneck.” Reports today also pointed out that transmitting via light allowed further distances of data transfer while minimizing risk of lost data.

Again, today’s announcement has more to do with the process of fabricating the technology, which had already been demonstrated. IDG News Service sums it up well: IBM has shown that it’s possible to “bake optical circuitry into silicon processors using existing fabrication techniques, which could set the stage for radically faster and lower-cost computer communications.” The BBC explains that many data centers already use optical cables to shuttle around data, but they’ve had to have expensive equipment to convert photon-data into electron-data.

IBM presented the breakthrough at the 2012 IEEE International Electron Devices Meeting.

miércoles, 26 de diciembre de 2012

What Do Lizard Tails Have In Common With Toilet Paper?

by Ed Yong


Toilet paper comes with lines of small cuts between the individual sheets, so it is easy to tear one off at pre-determined places. A gecko’s tail works in the same way.

Geckos, skinks, and many other small lizards are known for their ability to amputate their own tails when threatened by predators. The tails don’t break off at random places. Instead, they have sets of “score lines”, where the tissue on either side is loosely stuck together and can be easily separated. The gecko’s tail effectively comes pre-severed along several easy-to-tear lines.

But shedding a tail is more complex than it might seem. It’s not that a biting predator just pulls it off. The lizard helps the process along by contracting its muscles, which is why it takes more force to break the tail of an unconscious or dead lizard. Typically, the animal jettisons the tail just before the place where it was grabbed. After all, a tail is useful for communication, balance, storing fat, and even aerobatics—it’s not a thing to be casually lost, and the lizard benefits by detaching as little as possible.

Scientists have studied tail-shedding, or “caudal autotomy”, for several decades (there’s a good review here), focusing on when, why and how it happens. It’s the last one that interested Kristian Sanggaard from Aarhus University, who wanted to understand how the tail’s microscopic structures helped it to break off. To do that, he studied the Tokay gecko from south-east Asia, one of the largest of the 1,500 gecko species.

Here’s a slice through one of the gecko’s tail segments, stained with different dyes to highlight the various tissues. You can see the scales in dark blue running along the top and bottom, muscle fibres in red, and a huge core of white fat.
Section through a gecko's tail, showing clear "score lines" between segments
The segments are immediately obvious, with clear lines running through the fat and muscle. These divisions become less clear near the scales, but Sanggaard noticed dense clusters of collagen fibres at the points where the segments separate. You can see these in the image below (and the insets in the image above)—they’re the even patches blue in the midst of more marbled areas. The yellow arrows show the score line where the two segments break away from one another.

Along this line are dark blue dots. These are cells, and Sanggaard likens them to a zipper. It’s possible that when the lizard wants to shed its tail, the cells secrete substances that weaken the collagen, allowing the tissue to split apart more easily.
Left: yellow arrows show a ready-made score line in a gecko's tail. Right: a line of cells forming a zipper in the tail

Gecko tail segment showing muscle wedges
The tips of the broken tail segments end in wedge-shaped ‘fingers’ of white muscle. In an intact tail, these wedges fit into grooves within the preceding segment, like the finger joints you see on furniture.

Sanggaard looked at them under a powerful electron microscope, and saw that the muscle fibres end in mushroom-shaped tips. When the tail is intact, these fibres have flat heads that meet one another and stick together. When it’s time to detach the tail, Sanggaard thinks that the muscles contract and the ends expand into the rounded mushroom shapes. This reduces the adhesive forces between them, and allows the segments to disconnect.

An MRI scan of an unbroken tail confirmed his suspicions. There are clean gaps between adjoining segments with no structures running through them. This means that they’re held together by sticky forces, rather than by any physical anchors. In this way, the gecko gets the best of both worlds – a tail that holds together under normal circumstances, but that can be easily broken off at pre-determined points when its life is in danger.
Muscle fibres at the end of gecko tail segements end in mushroom shapes
That’s not the end of its defence, though. The severed tail will dance, writhe and wriggle for up to half an hour, probably to distract the predator’s attention from the escaping lizard or to put it off entirely. And if the tail isn’t eaten, the lizard will often return to it later to gulp it down itself. After all, why waste so much valuable fat?

Reference: Sanggaard, Danielsen, Wogensen, Vinding, Rydtoft, Mortensen, Karring, Nielsen, Wang, Thogersen & Enghild. 2012. Unique Structural Features Facilitate Lizard Tail Autotomy. PLoS ONE

In the Flesh: The Embedded Dangers of Untested Stem Cell Cosmetics

Unapproved procedures and skin care products endanger consumers and clinical research

Image: Credit: Nissim Benvenisty, via Wikimedia Commons
When cosmetic surgeon Allan Wu first heard the woman's complaint, he wondered if she was imagining things or making it up. A resident of Los Angeles in her late sixties, she explained that she could not open her right eye without considerable pain and that every time she forced it open, she heard a strange click—a sharp sound, like a tiny castanet snapping shut. After examining her in person at The Morrow Institute in Rancho Mirage, Calif., Wu could see that something was wrong: Her eyelid drooped stubbornly, and the area around her eye was somewhat swollen. Six and a half hours of surgery later, he and his colleagues had dug out small chunks of bone from the woman's eyelid and tissue surrounding her eye, which was scratched but largely intact. The clicks she heard were the bone fragments grinding against one another.

About three months earlier the woman had opted for a relatively new kind of cosmetic procedure at a different clinic in Beverly Hills—a face-lift that made use of her own adult stem cells. First, cosmetic surgeons had removed some the woman's abdominal fat with liposuction and isolated the adult stem cells within—a family of cells that can make many copies of themselves in an immature state and can develop into several different kinds of mature tissue. In this case the doctors extracted mesenchymal stem cells—which can turn into bone, cartilage or fat, among other tissues—and injected those cells back into her face, especially around her eyes. The procedure cost her more than $20,000, Wu recollects. Such face-lifts supposedly rejuvenate the skin because stem cells turn into brand-new tissue and release chemicals that help heal aging cells and stimulate nearby cells to proliferate.

During the face-lift her clinicians had also injected some dermal filler, which plastic surgeons have safely used for more than 20 years to reduce the appearance of wrinkles. The principal component of such fillers is calcium hydroxylapatite, a mineral with which cell biologists encourage mesenchymal stem cells to turn into bone—a fact that escaped the woman's clinicians. Wu thinks this unanticipated interaction explains her predicament. He successfully removed the pieces of bone from her eyelid in 2009 and says she is doing well today, but some living stem cells may linger in her face. These cells could turn into bone or other out-of-place tissues once again.

Dozens, perhaps hundreds, of clinics across the country offer a variety of similar, untested stem cell treatments for both cosmetic and medical purposes. Costing between $3,000 and $30,000, the treatments promise to alleviate everything from wrinkles to joint pain to autism. The U.S. Food and Drug Administration (FDA) has not approved any of these treatments and, with a limited budget, is struggling to keep track of all the unapproved therapies on the market. At the same time, pills, oils, creams and moisturizers that allegedly contain the right combination of ingredients to mobilize the body's resident stem cells, or contain chemicals extracted from the stem cells in plants and animals, are popping up in pharmacies and online. There's Stem Cell 100, for example, MEGA STEM and Apple Stem Cell Cloud Cream. Few of these cosmetics have been properly tested in published experiments, yet the companies that manufacture them say they may heal damaged organs, slow or reverse natural aging, restore youthful energy and revitalize the skin. Whether such cosmetics may also produce unintended and potentially harmful effects remains largely unexamined. The increasing number of untested and unauthorized stem cell treatments threaten both people who buy them and researchers hoping to conduct clinical trials for promising stem cell medicine.

When is a skin cream a drug?
So far, the FDA has only approved one stem cell treatment: a transplant of bone marrow stem cells for people with the blood cancer leukemia. Among the increasing number of unapproved stem cell treatments, some clearly violate the FDA's regulations whereas others may technically be legal without its approval. In July 2012, for example, the U.S. District Court upheld an injunction brought by the FDA against Colorado-based Regenerative Sciences to regulate just one of the company's several stem cell treatments for various joint injuries as an "unapproved biological drug product." The decision hinged on what constitutes "minimal manipulation" of cells in the lab before they are injected into patients. In the treatment that the FDA won the right to regulate, stem cells are grown and modified in the lab for several weeks before they are returned to patients; in Regenerative Sciences's other treatments, patients' stem cells are extracted and injected within a day or two. Regenerative Sciences now offers the legally problematic treatment at a Cayman Island facility.

Many stem cell cosmetics reside in a legal gray area. Unlike drugs and "biologics" made from living cells and tissues, cosmetics do not require premarket approval from the FDA. But stem cell cosmetics often satisfy the FDA's definitions for both cosmetics and drugs. In September 2012 the FDA posted a letter on its Web site warning Lancôme, a division of L'Oréal, that the way it describes its Genifique skin care products qualify the creams and serums as unapproved drugs: they are supposed to "boost the activity of genes," for example, and "improve the condition of stem cells." Other times the difference between needing or not needing FDA approval comes down to linguistic nuance—the difference between claiming that a product does something or appears to do something.

Personal Cell Sciences, in Eatontown, N.J., sells some of the more sophisticated stem cell–based cosmetics: an eye cream, moisturizer and serum infused with chemicals derived from a consumer's own stem cells. According to its website and marketing materials, these products help "make skin more supple and radiant," "reduce the appearance of fine lines and wrinkles around the eyes and lips," "improve cellular renewal" and "stimulate cell turnover for renewed texture and tone." In exchange for $3,000, Personal Cell Sciences will arrange for a participating physician to vacuum about 60 cubic centimeters (one quarter cup) of a customer's fat from beneath his or her skin and ship it on ice to American CryoStem Corp. in Red Bank, N.J., where laboratory technicians isolate and grow the customer's mesenchymal stem cells to around 30 million strong. Half these cells are frozen for storage; from the other half, technicians harvest hundreds of different kinds of exuded growth factors and cytokines—molecules that help heal damaged cells and encourage cells to divide, among other functions. These molecules are mixed with many other ingredients—including green tea extract, caffeine and vitamins—to create the company's various "U Autologous" skin care products, which are then sold back to the consumer for between $400 and $800. When the customer wants a refill, technicians thaw some of the frozen cells, collect more cytokines and produce new bottles of cream.

In an unpublished safety trial sponsored by Personal Cell Sciences, Frederic Stern of the Stern Center for Aesthetic Surgery in Bellevue, Wash., and his colleagues monitored 19 patients for eight weeks as they used the U Autologous products on the left sides of their faces. A computer program meant to objectively analyze photos of the volunteers' faces measured an average of 25.6 percent reduction in the volume of wrinkles on the treated side of the face. Analysis of tissue biopsies revealed increased levels of the protein elastin, which helps keep skin taut, and no signs of unusual or cancerous cell growth.

Only skin deep?
Supposedly, the primary active ingredients in the U Autologous skin care products are the hundreds of different kinds of cytokines they contain. Cytokines are a large and diverse family of proteins that cells release to communicate with and influence one another. Cytokines can stimulate cell division or halt it; they can suppress the immune system or provoke it; they can also change a cell's shape, modulate its metabolism and force it to migrate from one location to another like a cowboy corralling cattle. Researchers have only named and characterized some of the many cytokines that stem cells secrete. Some of these molecules certainly help repair damaged cells and promote cell survival. Others seem to be involved in the development of tumors. In fact, some recent evidence suggests that the cytokines released by mesenchymal stem cells can trigger tumors by accelerating the growth of dormant cancer cells. Personal Cell Sciences does not pick and choose among the cytokines exuded by its customers' stem cells—instead, it dumps them all into its skin care products.

Based on the available evidence so far, topical creams containing cytokines from stem cells pose far less risk of cancer than living stem cells injected beneath the skin. But scientists do not yet know enough about stem cell cytokines to reliably predict everything they will do when rubbed into the skin; they could interact with healthy skin cells in a completely unexpected way, just as the unintended interplay between calcium hydroxylapatite and stem cells produced bones in the Los Angeles woman's eye. Stern acknowledges that unusual tissue growth is a concern for any treatment based on stem cells and the chemicals they release. "Down the line, we want to continue watching that," he says. Unlike many other clinics, he and his colleagues have been keeping tabs on their patients through regular follow-ups. John Arnone, CEO of American CryoStem and founder of Personal Cell Sciences, says the fact that U Autologous skin care products contain such a diversity of cytokines does not bother him: "I've seen worse things out there. I've been putting this formulation for almost a year on myself prior to the study. I'm the best guinea pig here."

Beyond the considerable risks to consumers, unapproved stem cell treatments also threaten the progress of basic research and clinical trials needed to establish safe stem cell therapies for serious illnesses. By harvesting stem cells, subsequently nourishing them in the lab and transplanting them back inside the human body, scientists hope to improve treatment for a variety of medical conditions, including heart failure, neurodegenerative disorders like Parkinson's, and spinal cord injuries—essentially any condition in which the body needs new cells and tissues. Researchers are investigating many stem cell therapies in ongoing, carefully controlled clinical trials. Some of the principal questions entail which of the many kinds of stem cells to use; how to safely deliver stem cells to patients without stimulating tumors or the growth of unwanted tissues; and how to prevent the immune system from attacking stem cells provided by a donor. Securing funding for such research becomes all the more difficult if shortcuts taken by private clinics and cosmetic manufacturers—and the subsequent botched procedures and unanticipated consequences—imprint a stigma on stem cells.

"Many of us are super excited about stem cells, but at same time we have to be really careful," says Paul Knoepfler, a cell biologist at the University of California, Davis, who regularly blogs about the regulation of stem cell treatments. "These aren't your typical drugs. You can stop taking a pill and the chemicals go away. But if you get stem cells, most likely you will have some of those cells or their effects for the rest of your life. And we simply don't know everything they are going to do."