2009-08-28

Microscopes zoom in on molecules at last

Pentacene as you've never seen it before (Image: IBM and Science)Thanks to specialised microscopes, we have long been able to see the beauty of single atoms. But strange though it might seem, imaging larger molecules at the same level of detail has not been possible – atoms are robust enough to withstand existing tools, but the structures of molecules are not. Now researchers at IBM have come up with a way to do it.

The earliest pictures of individual atoms were captured in the 1970s by blasting a target – typically a chunk of metal – with a beam of electrons, a technique known as transmission electron microscopy (TEM).

Leo Gross and his colleagues at IBM in Zurich, Switzerland, modified the AFM technique to make the most detailed image yet of pentacene, an organic molecule consisting of five benzene rings (see picture).

The molecule is very fragile, but the researchers were able to capture the details of the hexagonal carbon rings and deduce the positions of the surrounding hydrogen atoms.

One key breakthrough was finding a way to stop the microscope's tip from sticking to the fragile pentacene molecule because of attraction due to electrostatic and van der Waals forces – van der Waals is a weak force that operates only at an intermolecular level.

The team achieved this by fixing a single carbon monoxide molecule to the end of the probe so that only one atom of relatively inactive oxygen came into contact with the pentacene.

The image is "astonishing", says Oscar Custance of Japan's National Institute for Materials Science in Tsukuba. In 2007, his team used AFM to distinguish individual atoms on a silicon surface, but he acknowledges that the IBM team has surpassed this achievement. "This is the highest resolution I have ever seen," he says.

http://www.newscientist.com/article/dn17699-microscopes-zoom-in-on-molecules-at-last.html

2009-08-27

The Time to Unlearn is Now!

This is the latest iteration of famous "Shift Happens" video with a focus on social media. If nothing else, it should serve as a reminder of to all of us why we must constantly unlearn. Enjoy!

Social Media Revolution

http://www.unlearning101.com/fuhgetaboutit_the_art_of_/2009/08/the-time-to-unlearn-is-now.html

Agile robots, dexterous robots

Agile quadruped robot: Boston Dynamics
Fast dexterous robotic hand: Forget about clumsy, lumbering robots.
Think fast, precise, and acrobatic.

Robotic hand
BigDog

http://metamodern.com/2009/08/27/agile-robots-dexterous-robots-with-videos/

Artificial life will be created 'within months'

Scientists are only months away from  creating artificial life, it was claimed yesterday.

Dr Craig Venter – one of the world’s most famous and controversial biologists – said his U.S. researchers have overcome one of the last big hurdles to making a synthetic organism.

The first artificial lifeform is likely to be a simple man-made bacterium that proves that the technology can work.

But it will be followed by more complex bacteria that turn coal into cleaner natural gas, or algae that can soak up carbon dioxide and convert it into fuels.

They could also be used to create new vaccines and antibiotics.

The prediction came after a breakthrough by the J Craig Venter Institute in Maryland.

Researchers successfully transferred
the DNA of one type of bacteria into a yeast cell, modified it and then transferred it into another bacterial cell.

http://www.dailymail.co.uk/sciencetech/article-1208047/Life-order-Man-organisms-months-say-biologists.html?ITO=1490



2009-08-26

Found: first amino acid on a comet

An amino acid called glycine has been found in dust collected by the Stardust spacecraft, which flew by Comet Wild 2 in 2004 (Illustration: NASA/JPL)An amino acid has been found on a comet for the first time, a new analysis of samples from NASA's Stardust mission reveals. The discovery confirms that some of the building blocks of life were delivered to the early Earth from space.

Amino acids are crucial to life because they form the basis of proteins, the molecules that run cells. The acids form when organic, carbon-containing compounds and water are zapped with a source of energy, such as photons – a process that can take place on Earth or in space.

Previously, researchers have found amino acids in space rocks that fell to Earth as meteorites, and tentative evidence for the compounds has been detected in interstellar space. Now, an amino acid called glycine has been definitively traced to an icy comet for the first time.

"It's not necessarily surprising, but it's very satisfying to find it there because it hasn't been observed before," says Jamie Elsila of NASA's Goddard Space Flight Center, lead author of the new study. "It's been looked for [on comets] spectroscopically with telescopes but the content seems so low you can't see it that way."

http://www.newscientist.com/article/dn17628

2009-08-12

First Steps Toward A Machine-Controlled Human Cell

A semipermeable membrane encloses each of your cells, selectively allowing molecules in and out. And now, scientists have figured out how to use nanowires to control the mechanism that makes your cells permeable, thus creating a computer-regulated cell.

A team led by Lawrence Livermore Lab scientists Nipun Misraa and Julio A. Martinez worked on the discovery, and their results were published earlier this week in PNAS. According to a release about the research:

[The researchers] created a biomechanical hybrid in which nanowires are coated in a lipid bilayer-the same type of membrane that envelopes cells and controls the passage of molecules in and out of the cell. The authors incorporated gated channels in this membrane, and used molecular transport through these channels to trigger an electric signal. The researchers show that the nanowire circuit can be used to make the channels open and close as they would in a biological cell. Although their work is currently in an early stage, later versions of the nanowire technology could find applications in biosensing, neuroscience, and medicine.

There are two things that are very exciting about this early-stage research. One, it means that cellular membranes could be incorporated into computerized devices that are designed to respond to molecules in the environment. Essentially, you could have a cellular sensor at the end of a nanowire.

http://io9.com/5335779/first-steps-toward-a-machine+controlled-human-cell




Pacific Biosciences Real Time DNA Sequencing $100 Genomes releasing 2013

Pacific Biosciences has a Single Molecule Real-Time (SMRT) DNA sequencing, due to be released commercially in 2010 and could enable $100 genome sequencing in 15 minutes in 2013.

The second generation real time DNA reader in 2013 is the one that is expected to hit the $100 genome sequencing price. They will release a product in 2010 but it will not be that cheap.

Instead of inspecting DNA copies after polymerase has done its work, SMRT sequencing watches the enzyme in real time as it races along and copies an individual strand stuck to the bottom of a tiny well. Every nucleotide used to make the copy is attached to its own fluorescent molecule that lights up when the nucleotide is incorporated. This light is spotted by a detector that identifies the color and the nucleotide -- A, C, G, or T.

By repeating this process simultaneously in many wells, the technology hopes to bring about a substantial boost in sequencing speed. "When we reach a million separate molecules that we're able to sequence at once … we'll be able to sequence the entire human genome in less than 15 minutes," said Turner.

http://nextbigfuture.com/2009/08/pacific-biosciences-real-time-dna.html

2009-08-11

Immortality improves cell reprogramming

p53Specialized adult cells made 'immortal' through the blockade of an antitumour pathway can be turned into stem-like cells quickly and efficiently.

The findings — which should make it easier to generate patient-specific cells from any tissue type, including certain diseased cells that have proved difficult to transform — suggest that cellular reprogramming and cancer formation are inextricably linked.

The studies also shed light on the mechanism of tumour formation, says study author Juan Carlos Izpisúa Belmonte, a developmental biologist at the Salk Institute for Biological Studies in La Jolla, California, and at the Center of Regenerative Medicine in Barcelona, Spain. Because it's now clear that p53 has a key role in both nuclear reprogramming and cancer development, Izpisúa Belmonte says, tumours can be thought of as cells that acquire more and more stem-cell-like characteristics — such as the ability to keep reproducing themselves forever. "If you connect the dots, you can say that cancer is really a de-differentiation problem," he says.

http://www.nature.com/news/2009/090809/full/news.2009.809.html