All posts by Debjyoti Bardhan

Is a science geek, currently pursuing some sort of a degree (called a PhD) in Physics at TIFR, Mumbai. An enthusiastic but useless amateur photographer, his most favourite activity is simply lazing around. He is interested in all things interesting and scientific.

No Reason To Fear The Supermoon Tomorrow; Just Enjoy It

This one’s really a personal note, but I want to share it with everyone. The last time the moon came really close to the Earth and it was a full moon night was on March 19, 2011. It was the supermoon event – or should I say The Supermoon event – that won’t find a duplicate in 18 years hence. It was also a perfect event for astrologers, soothsayers and anyone willing to stick their neck out for any sort of prediction to con people. Of course, the predictions need not be right – the fear would earn them thousands by the hour. And all of this became personal when people who I know well started asking me if this is indeed true!

The Supermoon Event on 19th March, 2011. (Courtesy: Reuters)

So what were the claims? There were claims of earthquakes striking, of natural disasters occurring and of events happening that would destroy the Earth before the “impending” 2012 date! Are these true, I was asked. Of course not, I answered. But then why so many warnings? Why so many astrologers saying so? Are they all wrong?

People are much crueler to politicians and doctors as opposed to charlatans! Apparently, both politicians and doctors can lie – even at great risk – just for a few bucks, but astrologers and psychics just won’t! Yeah, really!

The world is NOT coming to an END!

So here it is – my message loud and clear. There is going to be nothing odd happening on supermoon night. Yes, except for slightly higher tides that is. There is no positive correlation about the occurrence of earthquakes and the supermoon event. Furthermore, seismic forces are very powerful orders of magnitude more powerful than just lunar gravitational forces.

So here is the bottomline – enjoy the supermoon. Let go of any worries you might have about the supermoon bringing destruction upon you. Do nothing different! But of course, if you’re a real romantic, this is the perfect night to spend with your beloved under the stars. Let the magic of the Earth’s only natural satellite sweep you off your feet!

Lunar Alert: Supermoon To Be Spectacular This Week; Too Bad For The Meteor Shower

The moon will go ‘super’ this weekend, but that will mean bad news for the meteor shower watchers. The Supermoon, or the year’s biggest full moon, will delight all on 5th of May, 2012, starting from 2335 EST (or 0335 GMT on May 6th). Even though the moon will be at its biggest for just a few hours, the full moon will appear to last for a full three days starting on 4th May till 6th May.

Killed by the light

Unfortunately, the bright moon will wipe out the faint Eta Aquarids, the meteor shower from the debris of the Halley comet. However, given that the Eta Aquarids register at a high count of 60 meteors per hour, one shouldn’t lose all hope. Let’s just say that it won’t be seen in its usual self. Meteor shower enthusiasts will agree that the Aquarids are not really that bad a miss.

The Supermoon happens at the full moon when the moon is closest to the Earth. The 2011 Supermoon was spectacular – the moon won’t be that close to the Earth in another 18 years. This year’s Supermoon won’t be that great, but it will still be quite a sight, with the Moon appearing 14% bigger and 28% brighter than usual full moon nights.

Capturing it on film!

The Moon

Photo enthusiasts interested in sky watching should definitely aim at photographing the Supermoon. Last year’s was a bumper catch and this time too people are optimistic. A tripod is not necessary, as you’ll require really small exposure time for the moon, but getting to a place with a clear sky will definitely mean a lot for the clarity of the photo. Unlike other night photos, you will be well-advised to keep the ISO of your camera sensor low.

The Meteors

And as for the Eta Aquarids, we aren’t very optimistic, especially if you were planning to photograph them. Living in the Southern Hemisphere will give you a slight advantage and you’ll be lucky to see a few good and bright streaks. The fact that you won’t be able keep your camera shutter open for most of the area in the sky, due to the bright moon, will not help your cause. Sorry…

Though this might seem early, do plan on having a great lunatic weekend everyone.

Preserved Blood From 5300 Year Old Iceman Is World’s Oldest!

An open wound on a corpse is like a time machine – especially if the corpse is 5300 years old. Meet the most famous 5300 year old, his body preserved in as pristine a condition as this much time will allow – Oetzi. He was found in the Italian Alps, on the Oetz valley (and thus his name) in 1991 and since then has aroused considerable interest because of his well-preserved features.

Getting details

Scientists have been able to figure out that Oetzi died from a spear wound. He probably died soon after the strike and not from an infection from the wound. An axe and scattered arrow fragments lay around him. Some have even reconstructed Oetzi’s face, giving him a grizzly look of a stern, but aging hunter. Brown eyes were a figment of imagination, but they look good on him. He is the ultimate prehistoric fashion model.

Oetzi - probably

So well preserved is Oetzi that scientists have even been able to extract valuable DNA samples from whatever remains of his skin. Nothing useful could be concluded. They have also extracted mitochondrial DNA from his intestines. Mitochondria are small bodies living within cells. They contain their own DNA, apart from the nuclear DNA. Hereditary features are caused by nuclear DNA – the ‘familiar one’ – while the mitochondrial DNA remains inactive. It can only be passed down through the maternal line.

The DNA gave some tantalizing hints as to where Oetzi might have hailed from or what his biological ancestry might have been. Scientists speculate that he might be East European, but they aren’t very sure. Among other things, scientists speculate that he might have been infertile!

The preserved remains.

The blood

The latest in the Oetzi story features his blood. Blood cells degrade rather rapidly, but Oetzi even has blood preserved underneath his skin. This marks the oldest red blood cells ever recorded! Researchers at the Center for Smart Interfaces, University of Darmstadt, Germany, found that atomic force microscopy revealed minute amounts of blood in thin slices of tissue.

The RBC's as seen under an AFM. (Courtesy: BBC)

Atomic force microscopy relies on mapping out the atomic topography of a surface using a tiny atomically sharp metal tip. The concave shape of red blood cells clearly shows up (figure above)!

But something is anomalous – the fibrin levels are low. Fibrin helps blood to clot. It is found in very high quantities in fresh wounds. The fact that the blood will be preserved but not the fibrin seems far-fetched, so maybe Oetzi died slowly, due to a bleed or an infection rather than directly from a spear wound.

The dead do speak.

Alarm Bells Ring As Eight Patients Are Confirmed With TB Resistant To All Known TB Drugs

The ticking time bomb is giving signals that it is coming to the end of its countdown. The National Tuberculosis Institute (NTI), Bangalore, has confirmed eight cases all reporting TB germs resistant to all known TB drugs. A confirmatory notice has also been sent to the Central TB Division or CTD, New Delhi.

Twelve patients with symptoms of Tuberculosis (TB) were admitted to the Hinduja hospital on January 6th. Doctors soon declared them infected with Totally Drug Resistant TB (TDR-TB). Three out of the 12 died soon after. Sputum samples from all the 12 were sent for testing. Eight came out positive for a strain more resistant than earlier thought.

Triggering the time-bomb

Resistance to drugs generally results from the overuse of antibiotics. It’s simple evolution, really. Few of a population of TB germs may develop a genetic factor enabling it to resist a drug administered on the patient, say drug A. These few are the only surviving members of the population. Now, these multiply, giving rise to the next generation of germs resistant to this particular drug. When it infects another patient, a new drug – say drug B – is needed. Some members of this new population can then develop resistance to drug B, while retaining its resistance to drug A. Over prescription of medicines known to work on TB germs accelerates this process and very soon we get TB germs resistant to multiple drugs. This is what is referred to as Multi-Drug Resistant TB (MDR-TB).

TDR-TB refers to TB which are resistant to first line drugs. First line drugs are drugs proven to work against the bacteria, with the least amount of side-effects. There is a second line, which may not be as effective, or may produce more side-effects, or maybe not as well clinically tested as first line drugs. Second line drugs are used when first line ones fail. MDR-TB is resistant to many second line drugs as well.

Even worse

Eight of the Hinduja patients were infected with TB that showed resistance to both first and second-line drugs, making it Extremely Drug Resistant TB (XXDR-TB). However, WHO doesn’t recognize this classification. The case has been documented on the Directly Observable Treatment Shortcourse Plus (DOTS+) log. Doctors are still to figure out the line of treatment for these eight patients.

The TB timebomb is ticking… maybe beyond our control now!

SpaceX Static Fires Its Falcon Rocket; Dragon Sleeps Till 7th May

The next step in space will be taken on the 7th of May, but that was preceded on 30th April ’12 by the static fire of the launch vehicle. SpaceX, the company determined to take the mantle of NASA’s Space Shuttle program, will be launching their Dragon Space capsule on the 7th of May. Today they successfully static fired Falcon, the rockets that are meant to carry the Dragon into outer space.

The Falcon Static Launch (Courtesy: SpaceX)

Static fire means that the rocket doesn’t really launch and remains useable for a second time – or for the actual launch. The test wasn’t free of glitches, however. The scheduled test was at 1500 EST (or 1900 GMT), but while 47 seconds were remaining on the clock, the rocket’s engines showed a glitch, which was later traced down to a computer error.

The static launch was rescheduled for 1615 EST. There was no problem this time and the nine Merlin engines that will power the mammoth to space fired for two seconds, while the booster remained attached to the pads.

No fingers crossed

A static launch is a bit weird, but SpaceX doesn’t want to take any chances. NASA has been feeding this organization money and technology, so that they can be a proper replacement to the Space Shuttle. Here’s the time of reckoning. NASA is weighing the options of going on to build a new fleet of vehicles – Space Shuttle 2.0, if you wish – and of relying totally on SpaceX and SpaceX-like private companies to give them a lift to the heavens.

Photo from a test launch of the Falcon rockets (Courtesy: SpaceX)

SpaceX is not the only one with the prestigious (and lucrative) NASA contract. Virginia based Orbital Technological Corp. have also gained NASA’s trust. They are contracted for eight cargo delivery missions using its own Cygnus and Antares rockets to the International Space Station. The first of the launches will happen later this year.

The actual launch will happen on May 7th. The launch will be telecast live on SpaceX’s website. Be sure to keep an eye out for us – we will keep you informed with the latest.

Watch the video of the static launch here:

Concepts of Number Line and Time May Not Be As Intuitive As Previously Thought

Mathematics, often romanticized as human intuition, may not be as natural to the human race after all. In a new study conducted by the a team of scientists, led by Rafael Nunez, director of Embodied Cognition Lab, it appears that abstract mathematical concepts like the number line, which involves the mapping of numbers onto space, need to be taught and aren’t ‘hard-wired’.

Really so intuitive? Think again!

Nunez et al studied an indigenous tribal group from Papua New Guinea called the Yupno. The group lives in a remote part of the upper Yupno Valley in Papua New Guinea. The place has no roads. The team used a small plane and then hiked, carrying heavy equipment like solar panels, since the valley has no electricity.

The study

The main study was conducted with three groups – one comprised 14 illiterate adults, another comprising 6 adults who had received very basic schooling from within the tribal community and another control group in California, comprising adults with formal schooling. All the three groups were given several objects and a long line. Then they were asked to arrange these objects on the number line.
The Yupno were given oranges. The first group (of unschooled adults) arranged the oranges, but stacked them up at the two endpoints and a put a few in the middle, totally ignoring the extension of the line in between, which is one of the most important properties of the number line. The second group did a little better, using the extension a bit more, but not quite as evenly as it should be. The control group in California treated the number line as it should be. All this suggests only one thing – that the concept of numbers, especially their mapping onto space, is a concept that has to be taught and is not ingrained in the human brain. The ability to build this intuition might be evolutionary, but not the intuition itself!

What about time?

The team also analysed the crucial concept of time. We tend to associate the flow of time with spatial position, associating ‘forward’ for future and ‘backward’ for past. Interestingly, the Aymara of the Andes, a previously studied group of Nunez et al., does the reverse. The Yupno uses ‘uphill’ and ‘downhill’, says Nunez. They even use the three-dimensional topography of the valley to describe time, obviously conflicting with just the forward and backward 2-D notions of time.

Cooperrider, a co-author in the study, says:

When confronted with radically different ways of construing experience, we can no longer take for granted our own. Ultimately, no way is more or less ‘natural’ than the Yupno way.

There you go – Mathematics, or even time, is not as universal as we thought. If some definition or notion of mathematics seems obvious, it may be because we lack imagination.

The study appears here:http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0035662

Presenting Deus: A Full Blown Simulation of the Entire Universe

Scientists have been able to recreate the entire Universe inside a computer for the first time ever. A simulation running on a supercomputer, tracking a mind boggling 550 billion particles as they evolve, has been able to recreate the structure of the Universe right from the Big Bang to the present day.

Simulating the Standard Model of Cosmology

This is the first in the series of three simulations to be carried out on GENCI’s new supercomputer, CURIE at CEA’s TGCC (Tres Grand Centre de Calcul) performed by researchers from Laboratoire Univers et Theorie (LUTH). This takes into account the standard model of cosmology with the cosmological constant built in. Successive runs will improve upon this result with more data, especially about the distribution of dark matter and dark energy. The project, called Deus: full Universe run, will seek answers to the cosmological questions in a way similar to what the LHC follows in order to get answers.

Comparing Deus' size to previous simulations! Bottomline: Deus is HUGE!

Why simulation?

The physics at the LHC is massively complicated by the presence of so many particles and so many end states of a certain collision. It is impossible to analytically solve for the end state, so scientists use models before they begin an experiment. These simulations reveal what the most likely result of a certain collision is given certain parameters and bounds on certain numbers. The actual run either confirms the simulation, or discards it. This is a far more efficient process than reconstructing the interaction by looking at the end states, which is the other alternative.

The Deus simulation does something like that. They let the 550 billion points evolve and see what the end state is. This has enabled them to count the number of galaxy clusters which are more massive than a hundred thousand billion solar masses (that’s VERY heavy, by the way) and the number comes out to be 144 million. The first galaxy cluster formed 2 billion years after the Big Bang, according to the simulation. It also shows the most massive galaxy cluster – with a mass of 15 quadrillion (or 15 thousand trillion) solar masses!

 

Relics of the Early Universe

The simulation also revealed fingerprints of the inflationary era in the form of fluctuations in the Cosmic Microwave Background Radiation. If the Big Bang and inflation is true, then there must be radiation left over, which is constantly weakening. This permeates all of the space in the Universe, thus the name Cosmic Microwave Background (CMB). It is believed that some quantum fluctuation, growing under the effect of gravity, gave rise to the galaxy and clusters we see today. The CMB was studied thoroughly by the WMAP studies. They also showed up in the simulation.

Where are we? That dot - that single dot - is the entire Milky Way!

The simulation also confirmed the presence of dark matter and gave a hint of how it might be distributed throughout the Universe. Present in this primordial virtual cosmic soup is the Baryon Acoustic Oscillations or BAO. This might be the answer to the long standing problem of baryon asymmetry – why matter outnumbers anti-matter in the Universe, whereas they should have been produced in equal numbers in the Early Universe.

Computing power – the sky is the limit

CURIE is one of the largest supercomputer facilities in the world. The whole simulation has taken a few years to put together. The whole project is expected to use more than 30 million hours (or 3500 years) of computing time on all CPU’s of CURIE. The amount of data processed comes out to be 150 PB (peta bytes). This amounts to all the data on 30 million DVD’s. State-of-the-art compression technology has allowed researchers to reduce this entire jungle to 1 PB.

Future

Two more simulations are to follow! They will test out rival cosmological models. The simulation is also expected to reveal structures we have not been familiar with before. This will provide scientists a search parameter for current projects like PLANCK and future ones like EUCLID.

More info at this CNRS press conference: http://www2.cnrs.fr/en/2013.htm

Google Celebrates Earth Day ’12 With Doodle

Earth Day! The day when there is a call for each one of us to do our little bits for the planet. Mobilize the Earth is the slogan, and this is the day to remind ourselves of the responsibilities again. Google honours Earth Day with a very beautiful doodle.

The Doodle

Google did this last year as well – coming up with an awesome doodle back then. This time, it’s not as great as the last year, but it’s very pleasing. The doodle shows flowers lined up in shapes that spell out ‘G-O-O-G-L-E’. The doodle is not a static picture, and you can see the flowers growing, representing the Earth full of beauty. The colour of the flowers on each of the letters is the same as the colours of the letters on the regular Google logo. Nice and subtle!

Renewing the Pledge to the Planet

We had told you the brief history of Earth Day last year. The pledge this year is multi-pronged. We need to find viable alternative energy sources, save species, plant more trees, reduce carbon footprint and, most importantly, provide enough resources to teachers all over the world so that the information can be brought to the millions of children who are to form the future of our planet. There is no guarantee, in fact quite the reverse, that they will be spared the massive environmental changes – the debts of the generations preceding them.

Resources

The official site of Earth Day is www.earthday.org/2012. You’ll find all the news you need about Earth Day and the activities. Remember this is just a formal token day – the work happens all around the year.

In order to fulfill the dream of ‘A Billion Acts of Green’, the Earth Day Network launched an initiative with acclaimed director James Cameron which involves planting a million trees. This has led to the swelling of the online community members to a staggering 900,000.

The coolest thing on the website is the Carbon Footprint calculator. The app takes in your location, asks a few simple questions and then spits out your carbon footprint. Cool!

Get to know how you can help! Everyone counts.

Scientists Create Artificial DNA, Observe Darwinian Evolution In Them

The very basis of life can now be created in the laboratory and it’s not unique. What more this artificial genetic material can mingle easily with the real thing, even evolving as the real thing does. The creation of artificial DNA and RNA strands have been reported by Pinheiro et al. They have even observed their evolution.

A new class of molecules, very similar, but not quite

Till now, the only molecules known to be capable of undergoing Darwinian evolution were RNA and DNA, but this discovery suggests that there might be a lot more candidates that fit the bill. There is really no “Goldilocks solution”.
DNA (or RNA) has a double helical structure, meaning that it looks like two strips of paper wound around each other in a helical fashion. The structure is ladder like – with each rung consisting of two nucleotide bases held together by sugar molecules.

The Structure of DNA. The A,C,G and T label the nucleotides.

Pinheiro’s group retained the nucleotides of DNA – the Adenine, Guanine, Cytosine and Thymine (or Uracil, in case of RNA) – but altered the sugars that bind these nucleotides together. In this way, he created XNA, with the ‘X’ standing for the sugar used. DNA, or deoxyribonucleic acid, uses deoxyribose as the sugar, while RNA, or ribonucleic acid, uses ribose as the sugar. But these use different sugars, thus giving them different names. For example, arabinose is the sugar in ANA, flourarabinose in FANA, threose in TNA, a “locked” ribose in LNA and a cyclohexane in CeNA.

Retention and copying of information

Here is the crucial bit: Even though the sugar bases were changed, the nucleobases being the same meant that these artificial XNA’s behaved exactly like the DNA found naturally. They could even pair up with the naturally found DNA.

Here is another crucial bit of the story: When DNA or RNA create copies of themselves, they use helper molecules called polymerases. These polymerases separate the two chains of the double helix structure, read the sequence of letters, helps in the formation of a similar chain, zips the whole thing back again and creates a new DNA molecule, all in this process called transcription. Evolution – or small genetic changes in the DNA structure – happens the copy of the DNA is not exactly like its parent. Environmental factors then ‘selects’ the more competitive versions of these modified DNA molecules and this helps them create more copies of themselves. Thus, a trait is acquired and another is lost.

Building your own genetic copy machines

The team had to build separate polymerase molecules to help transcribe the XNA’s. They were able to, thus, transcribe the code of the synthetic DNA to natural DNA and then back to the synthetic DNA. The XNA’s thus formed are just as immune or vulnerable to the original DNA. XNA’s must also be able to proliferate just like DNA does without any external help, in a process called amplification. Amplification was noticed with the artificial polymerases and the XNA’s. This is important, otherwise the XNA’s won’t be able to undergo Darwinian evolution like DNA.

In one of the experiments, a control was set up. The factors were controlled such that if the XNA did not ‘cling on’ to a particular protein, it would be washed away. Pretty soon more and more XNAs began developing this trait. This again proves that the two very important traits of inheritance through genetics and selection – information storage with high fidelity of copying and propagation of mutations – are not characteristics of just DNA or RNA. This gives the grand possibility of finding a whole new structure of biochemistry.

Maybe novel forms of life are not that far away in the future!

Study and the technical paper here: http://www.sciencemag.org/content/336/6079/341.abstract

Scientists Split The Electron, Create an ‘Orbiton’ For The First Time Ever

Condensed matter physicists are known for creating miracles and they haven’t disappointed! They have just split the electron into two, creating a hitherto unobserved ‘orbiton’ in the process. While this has immediate consequences in theoretical condensed matter physics, like figuring out how high temperature superconductivity occurs (more later), the very idea of this is just too cool.

An explanation for superconductivity?

The ‘pieces’ of the electron

Condensed matter physicists have long identified that in a chain of atoms (called a ‘spin chain’), aligned in a particular direction, especially in the presence of a magnetic field, electrons can be thought of as particles being made up of three components. One component represents the charge(a ‘holon’), another the spin (a ‘spinon’) and a third one should store the orbital location information (an ‘orbiton’). Do note, however, that these three components exist independently only inside the material, not outside it. Outside the material, the electron is just the elementary particle – unbreakable into other particles – just like we know it to be.

History revisited

Fifteen years ago, a team of scientists, led by C. Kim of Stanford University, split the electron into its holon and spinon components. The material they used was ‘one-dimensional’ Strontium Cuprate. Now, another team, led by J. van den Brink, have split the electron into a spinon and an orbiton, making it the first ever spectroscopic observation of a free orbiton. The material is another version of Strontium Cuprate.

Performing a miracle with a laser

The team fired a beam of X-ray photons into the one-dimensional material. The electrons in the outer orbitals were excited to a higher orbital. In this process, the electron can separate out into a spinon and an orbiton. And this is exactly what the scientists got.

When the electron got excited to a higher orbital, the laser light lost some energy. The scattered beam’s energy and momentum were plotted and compared with various computer simulations. The plot matched perfectly if one assumes that the electron has ‘split’ into an orbiton and a spinon. These two quasi-particles would be moving in opposite directions through the medium.

Van der Brink is more ambitious:

The next step will be to produce the holon, spinon and the orbiton at the same time

Problem in superconductivity

So what theoretical problem in superconductivity does it really solve?

The long standing problem in superconductivity (the phenomenon of flow of electric current through a material with zero resistance) has been the problem of high temperature superconductivity. No one know how some materials manage to superconduct at temperatures such as -196 degrees Celsius, which is much higher than the previously known -268 to -263 degree Celsius. No one knows what conducts the current through the material. There is a theory that orbitons might be the key.

To have the power to create your own materials and rediscover one of the oldest discoveries of ‘modern’ science is to be able to do modern day alchemy. It’s a miracle, indeed.

The paper appears here: http://www.nature.com/nature/journal/vaop/ncurrent/full/nature10974.html

Was Life On Mars Discovered 30 Years Ago?

Simply put, there is life on Mars – or at least that’s the most plausible explanation that NASA scientists can put forward in order to explain certain observations in the lab. A robotic mission launched thirty years ago, the Viking 1 and Viking 2, brought soil samples back to Earth and these have been thoroughly tested for the presence of Martian life, and the tests have been encouraging.

Life Hiding Somewhere?: Photo returned by the Viking Spacecraft (Photo Courtesy: GSFC, NASA)

One of the packages brought back by the Viking spacecraft was collected by the Labeled Release (LR) apparatus. This sample is particularly interesting.

The ticks of life

Soil microbes metabolize and release carbon dioxide, using up minerals in the soil. The carbon in the carbon dioxide contains one radioactive atom in a million million atoms, but since there are lots of carbon atoms around, there is a lot of radioactive carbon as well. And this shows up in any instrument that measures radioactivity, like a Geiger Counter. So the idea is that if a soil sample emits more than its share of radioactive rays, the chances are very high indeed that there are microbes inside, that are churning out carbon dioxide gas, which can escape and be detected. The detector will produce more counts than normal.

They found exactly that! A control sample was put in to confirm that this is indeed due to some source of microbe inside the soil sample. This sample was baked at a high temperature to kill any microbe that might be present. When the two samples were checked for radiation, the unbaked LR sample clocked around 10,000 counts per minute, while the background was only about 100.

However, this is not true of the other two experiments on the Viking spacecraft. This non-confirmation led to the dismissal of the probability of life.

The diurnal cycle of life

Life on any planet, especially if local, adjusts its living patterns – sleeping, hunting etc. – according to the clock on that planet. Lifeforms on Earth have a 24 hour clock schedule, but on Mars the day is 24.7 hours long, and that will be the so-called ‘circadian rhythm’.

The funny thing is that the radiation emitted by the LR apparatus sample also shows this daily cycle. The radiation goes down, indicating a period of inactivity, then goes up again. The oscillation is periodic with the exact period of 24.66 hours.

Joseph Miller, a neurobiologist at University of Southern California, and a member of the study says:

That is basically a circadian rhythm, and we think circadian rhythms are a good signal for life.

No one has yet cultured a Martian microbe. The next spacecraft explorer – Curiosity – which is scheduled to land on Mars in a few days will shed much more light on this very critical issue.

We may not only have company in the Universe, it might even be just next door.
Want more info? Visit this: http://www.ijass.org

Eureka? Stem Cells Breakthrough Allows a Possible AIDS Cure

Stem Cells are the way forward for medicine and this is another confirmation of that. Just ahead of the upcoming World AIDS day, comes a wonderful piece of news – stem cells can be used to cure AIDS. This has been demonstrated the case of mice.

The T-cells

There are specific cells in the body’s defense system which can recognize HIV cells and kill HIV-infected cells, called cytotoxic T-lymphocytes. However, because HIV prevents the immune system from proliferating the WBC’s (white blood corpuscles- the soldier cells) during an infection, the T-cells aren’t produced in sufficient quantities. Now, scientists are using blood stem cells and ‘programming’ them to form mature T-corpuscles in sufficient number to attack the infection properly.

The tests were done in a lab in California University and the experiment subject was a humanized mouse. By humanized, it simply means that the progress of the HIV infection in the mouse mimics the progress in humans.

The experiment

The experimental subjects were observed for progress. Blood tests were done on the second week and sixth week. The scientists found that the T-cell count had increased and the HIV level decreased! Is this the long sought after cure?

Dr. Scott G Kitchen, lead scientist in this study, said:

We believe that this is the first step in developing a more aggressive approach in correcting the defects in the human T cell response that allow HIV to persist in infected people.

There are a lot more drug trials that need to be conducted before this can be thought of as a cure. Further, these have to be tested on human patients and their efficacy measured. The first step is a very promising one. It’s too early to say, but this can be the cure against AIDS.

The study appears here: http://www.plospathogens.org/article/info%3Adoi%2F10.1371%2Fjournal.ppat.1002649

Evidences of Majorana Particles Seen In Nanowires

A particle can be its own anti-particle – this was the phenomenal insight of the mysterious physics genius Ettiore Majorana, who went missing in 1938 and was never found. These particles have been widely searched for and has generated considerable amount of interest in the theoretical physics community, but have not been found. Now, the LHC has been quite actively searching for signatures of these particles.

A computer image of the nanowire created

Condensed Matter physicists join in…

Interestingly, and very importantly, a lot of modern day condensed matter research focusses on the type of signatures that Majorana particles can produce and how they can be detected. It is in this context that wonderful news comes in from a team of Dutch researchers, who have reported seeing signatures for these particles.

Device and Methodology

The team has been fabricated a device which comprises a nanowire forming a junction between a semiconductor and a superconductor. The team then applied a magnetic field parallel to the nanowire and this restricts electrons to only certain energies, creating so-called ‘band gaps’. Electrons can reside only in these band gaps.

The team then measured the conductivity of the material given different gate voltages and found that there are two small peaks in the conductances placed symmetrically about the zero bias voltage. Scientists think that these peaks are due to particles and anti-particles respectively, but they are just the same, i.e. they are Majorana fermions.

The team varied the magnetic field and the bias voltage over large ranges of values, but they dips stayed constant. All of this leads the team to conclude that the charge carriers in nanowire were indeed Majorana fermions.

The work appears here: http://www.sciencemag.org/content/early/2012/04/11/science.1222360.full.pdf

Don’t Know Whether a Word Is Real or Not? Ask a Monkey!

Reading – the primates are doing it right! A group of baboons was studied by the team of scientists led by Jonathan Grainger of CNRS and Aix-Marseille University, Marseille, France and they found that they can indeed read – and do so quite well.

The Underlying Science

When we read words, we use information we have acquired about those words over years. The information is primarily about the content of letters in the word, but involves many other forms as well, including an association of certain events, colours, personalities, emotions etc. The information relating the letters and how they are arranged in the word, called orthographic information, is the primary step taken by anyone learning how to read. This is the primary source of information that one uses to distinguish between real words and nonsense combination of letters. Humans have achieved a level of sophistication that even allows the concept of intricate spelling, identifying mistakes in spelling and etymology.

The study shows that orthographic information can be developed without any preexisting knowledge. That’s enough of abstract technical talk. In the experimental context, that simply means that the monkeys were really good at discriminating between actual words and nonsense ones.

How the Study Was Conducted

The monkeys were made to feel completely at ease, them being allowed to eat food and participate in the experiment at their own convenience. They could stop and start whenever they wanted. In the testing booths, they were presented with a four letter combination, either a sensible one like ‘WASP’ or something nonsense like ‘FSEV’. They could then tap at a plus sign on a touchscreen if they thought that the word was real, or an oval one if they reckoned that the word was just another combination of letters.

Of course, the monkeys were trained over a period of one and half months before this experiment, which, if you wanted to point out, would be much lesser than what a human child would take to learn words. Especially given the number of words involved. One baboon (VIO) got 81 words and another (DAN) got 308 words out of a total of 7832 non-words with nearly 75% accuracy! I am impressed.

The paper reporting the study appeared in Nature: http://www.sciencemag.org/content/336/6078/245.abstract

This just shows that reading and orthographic skills are not so rare in the primate family. All primates might be taught to read, to different degrees of success. The day is not far away when you’ll be able to chat online with a monkey… or you might have already done that.

Why No Tsunami After Giant Indonesia Quake, Ask Surprised Scientists

While the world has heaved a sigh of relief that the giant Indonesian quakedid not generate any tsunami, scientists are puzzled. Given the large magnitude of the quake, there should have been a tsunami, especially since the epicenter wasn’t very deep (just 33 km below the surface) and it lies directly beneath the sea. The question is really this then: Why was there such a huge tsunami during the 2004 quake, measuring 9.3 on the Richter Scale, while this one, just slightly weaker at 8.6 magnitude, didn’t generate anything even remotely similar?

The location of the quake that struck Indonesia. (Courtesy: BBC)

Two Important Factors

Preliminary investigations by geologists point to two factors which together contributed to the diminished effect. One is the strike-slip fault line and the other is that the earthquake occurred within a plate, rather than at a subduction zone. Let me explain this one sentence and the orgy of technical terms used.

Subduction Zone

Subduction zone refers to the zone at which two tectonic plates join. In this zone, plates may get submerged or raised. Subduction zones are regions where the major volcanoes of the world lie in, and thus is given the name “Ring of Fire”. Typically, these occur in the oceans. The entire of the Hawaiian region, for example, lies in the subduction zone. The really major earthquakes have all happened in this zone.

Subduction zone

The present earthquake didn’t happen at a subduction zone. The epicenter was about 150 km from the nearest subduction zone. No plate was submerged or raised. It was a really big intra-plate quake. What has surprised scientists is how big this quake actually was. More of this after a bit.

Strike Slip Fault

The earthquake occurred on a strike-slip fault, which means that the two adjacent plates slid past each other, releasing the built up tension, rather than submerge and rise. This is THE crucial difference between this quake and the 2004 one. The 2004 quake occurred on a normal fault. Land (the sea bed) was violently raised, while another part was submerged. The released tension was directed upwards, rather than sideways, causing the huge waves.

Strike-slip fault. Note how the landmasses slide past each other.
Normal Faulting. One can see the displaced striations and that makes it clear that the rock has been uplifted and submerged along the fault-line.

I want to ram home this crucial point: the difference was the presence of shear in the present earthquake. The fault line sheared (or pulled apart horizontally, along the ground), rather than jut upwards, like it had done during the devastating 2004 earthquake.

Formation of a tsunami.

Scientists are still learning new things though. They are surprised as to how a strike-slip earthquake can be so strong in magnitude. The record was held by the giant 1906 San Francisco earthquake, along the strike-slip San Andreas fault, which measured 7.8 on the Richter Scale.

A Tsunami did form!

Strictly speaking, a tsunami was generated. The Indonesian coast saw the increase of water level by about 1 m or 3.3 ft. However this is nothing compared to the about 30 m or 100 ft waves generated by the 2004 earthquake. The land however has shifted by nearly 70 ft in the northeast-southwest direction.

Residents left their homes in search of higher ground in Banda Aceh, once the tsunami alert was sounded. (Photo Courtesy: National Geographic)

All tsunami watches, issued for all countries across the Indian Ocean, had been lifted by yesterday night itself. Lucky definitely, but humanity needs all the luck it can get right now.