Knowledge Update

​New York, March 5 (IANS) At a time when humans are generating more data than hard drives, scientists have demonstrated that a computer operating system and a short movie could be stored on a DNA.

In a new study, published in journal Science, a pair of researchers at Columbia University and the New York Genome Center (NYGC) showed that an algorithm designed for streaming video on a cellphone can unlock DNA's nearly full storage potential by squeezing more information into its four base nucleotides.

The researchers showed that their coding strategy packs 215 petabytes of data on a single gram of DNA, which study co-author Yaniv Erlich believe was the highest-density data-storage device ever created.

According to the team, DNA is an ideal storage medium because it is ultra-compact and can last hundreds of thousands of years if kept in a cool, dry place.

"DNA won't degrade over time like cassette tapes and CDs, and it won't become obsolete -- if it does, we have bigger problems," said Erlich.

Erlich and his colleague Dina Zielinski stored six files into a DNA -- a full computer operating system, an 1895 French film "Arrival of a train at La Ciotat", a $50 Amazon gift card, a computer virus, a Pioneer plaque and a 1948 study by information theorist Claude Shannon.

They compressed the files into a master file, and then split the data into short strings of binary code made up of ones and zeros.

Using an erasure-correcting algorithm called fountain codes, they randomly packaged the strings into so-called droplets and mapped the ones and zeros in each droplet to the four nucleotide bases in DNA.

They also demonstrated that a virtually unlimited number of copies of the files could be created with their coding technique by multiplying their DNA sample through polymerase chain reaction (PCR) and that those copies, and even copies of their copies, and so on, could be recovered error-free.

​New York, March 5 (IANS) While some people believe tanning makes them more beautiful, this habit can actually damage their skin in the long run, leading to wrinkles and sagging skin, says a study.

"Ultraviolet radiation from the sun and indoor tanning beds not only can increase your risk of skin cancer but also can contribute to skin ageing," said Arianne Shadi Kourosh from the Massachusetts General Hospital, Boston, US.

"Moreover, other forms of radiation, such as heat and visible light, can negatively impact the skin, as can pollution, so protecting your skin from the environment can benefit both your health and appearance," Kourosh said in a statement released by the American Academy of Dermatology.

Since both types of UV rays -- long wave ultraviolet A (UVA) and short wave ultraviolet B (UVB) -- can damage the skin, it is important to use a broad-spectrum sunscreen that provides both UVA and UVB protection, with an SPF (Sun Protection Factor) of 30 or higher, Kourosh said.

Environmental factors can damage the skin in multiple ways, from UVB rays causing sunburns and uneven pigmentation to UVA and infrared radiation penetrating more deeply into the skin to damage existing collagen and reduce collagen production, resulting in wrinkles and sagging skin, Kourosh said.

Habitual UV exposure can cause blood vessels to become more prominent, causing skin redness, while visible light and pollution can cause uneven skin tone, she said.

Washington, March 4 (IANS) The Hubble space telescope has captured an image to showcase an incredible massive galaxy, UGC 12591, that lies just under 400 million light-years away from the Earth.

The galaxy and its halo together contain several hundred billion times the mass of the Sun -- four times the mass of the Milky Way, NASA said in a statement on Friday.

It also whirls round extremely quickly, rotating at speeds of up to 1.8 million kilometers per hour, it added.

UGC 12591 sits somewhere between a lenticular and a spiral. 

It lies in the westernmost region of the Pisces-Perseus Supercluster, a long chain of galaxy clusters that stretches out for hundreds of light-years ? one of the largest known structures in the cosmos.

Observations with Hubble are helping astronomers to understand the mass of UGC 12591, and to determine whether the galaxy simply formed and grew slowly over time, or whether it might have grown unusually massive by colliding and merging with another large galaxy at some point in its past, NASA said.

The Hubble Space Telescope is a collaboration between NASA and European Space Agency (ESA).

London, March 4 (IANS) Eating foods rich in omega-3 fatty acids could significantly reduce damage caused by air pollution, suggests new research.

Omega-3 fatty acids (OFAs), found in a variety of foods including in oily fish, soy beans and spinach, could reduce inflammation and oxidative stress caused by air pollution by up to half, according to the study conducted in mice.

However, the research also shows air pollution particles can penetrate through the lungs of lab animals into many major organs, including the brain and testicles. This raises the possibility that the health damage caused by toxic air is even greater than currently known, The Guardian reported on Friday.

"I would definitely recommend taking OFAs to counter air pollution problems," lead researcher Jing Kang, at Massachusetts General Hospital, part of Harvard Medical School in the US, was quoted as saying.

"OFAs are well known to have many other healthy benefits and the key thing is they are not like a drug, but a nutrient with so many benefits," Kang said.

Two to four grammes per day would be the equivalent dose in humans to that given to the mice, Kang said.

The research suggests that omega-3 fatty acids could provide an immediate, practical solution for reducing the disease burden of air pollution.

London, March 4 (IANS) Researchers have discovered a new way of developing painkillers that act only on inflamed tissues, while keeping healthy ones unaffected, suggesting that the severe side effects currently associated with these medicines might be avoided.

When used in an animal model, their prototype of a morphine-like molecule was able to produce substantial pain relief in inflamed tissues without severe side effects, according to a study published in the journal Science.

The team of researchers used computational simulation to analyse interactions at opioid receptors -- the cell's docking sites for painkillers. 

"By analysing drug-opioid receptor interactions in damaged tissues, as opposed to healthy tissues, we were hoping to provide useful information for the design of new painkillers without harmful side effects," said Christoph Stein from Charite - Universitatsmedizin Berlin in Germany.

Opioids are a class of strong pain killers and are mainly used to treat pain associated with tissue damage and inflammation, such as that caused by surgery, nerve damage, arthritis or cancer. 

Common side effects associated with their use include drowsiness, nausea, constipation and dependency and, in some cases, respiratory arrest. 

In this study, the the researchers showed that they were able to analyse morphine-like molecules and their interactions with opioid receptors. 

They were able to successfully identify a new mechanism of action, which is capable of producing pain relief only in the desired target tissues -- those affected by inflammation.

The new findings could lead to treating postoperative and chronic inflammatory pain without causing side effects. 

Doing so would substantially improve patient quality of life.

Washington, March 2 (IANS) In a first, scientists have measured rapidly varying temperatures in hot gas emanating from around a black hole and found that the winds can heat up and cool down in the span of just a few hours.

The findings, published in the journal Nature, could shed new light on how winds emanating from around a black hole can affect the environment of host galaxies.

For the study, the researchers used data from NASA's Nuclear Spectroscopic Telescope Array (NuSTAR) telescope and the European Space Agency's XMM-Newton telescope. 

"We know that supermassive black holes affect the environment of their host galaxies, and powerful winds arising from near the black hole may be one means for them to do so," said NuSTAR Principal Investigator Fiona Harrison, Professor at California Institute of Technology in the US.

"The rapid variability, observed for the first time, is providing clues as to how these winds form and how much energy they may carry out into the galaxy," Harrison said.

The black hole that the researchers observed is located in the active galaxy IRAS 13224-3809 in the constellation Centaurus.

To measure the temperatures of these winds created by disks of matter surrounding black holes, the team studied X-rays coming from the edge of the black hole. 

As they travel toward Earth, these X-rays pass through the winds, and some wavelengths of the X-ray spectrum are absorbed by different elements in the winds, such as iron and magnesium. 

By examining the holes, or "absorption features", in the X-ray spectrum as it reaches Earth, astronomers can learn more about the components of the wind.

While observing this spectrum, the team noticed that the absorption features were disappearing and reappearing in the span of a few hours. 

The team concluded that the X-rays were actually heating up the winds to very high temperatures so that they became incapable of absorbing any more X-rays. 

The winds then cool off, and the absorption features return, starting the cycle over again.

"This is the first time we have seen that winds are interacting with the black hole's radiation," study first author Michael Parker, postdoctoral scholar at University of Cambridge Institute of Astronomy in Britain

​New York, March 3 (IANS) NASA scientists have demonstrated that a new space weather warning system could help astronomers detect harmful solar particles much before they leave the sun's inner atmosphere -- critical extra time that could help protect astronauts in space.

Solar energy particles (SEPs) can move at nearly the speed of light -- so their total travel time can be less than an hour from the time they are accelerated near the sun to when they reach Earth.

In the study published in the journal Space Weather, scientists from NASA and the US National Center for Atmospheric Research, or NCAR, in Boulder, Colorado, showed how ground-based instruments called coronagraphs can help lengthen the warning time for solar particles.

Earth's magnetic field and atmosphere protect us on the ground from most of the harmful effects of space weather, but astronauts in low-Earth orbit -- or even, one day, in interplanetary space -- are more exposed to space weather, including bursts of fast-moving particles called solar energetic particles, or SEPs.

"Robotic spacecraft are usually radiation-hardened to protect against these kinds of events," said lead author on the study Chris St. Cyr, a space scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland. 

"But humans are still susceptible," Cyr said.

So NASA wants to help improve systems that would provide future astronauts with advance warning of incoming SEPs. 

In the recent paper, the scientists showed that tracking an associated kind of solar explosion -- fast-moving clouds of magnetic solar material, called coronal mass ejections -- can help.

Scientists observe coronal mass ejections using a type of instrument called a coronagraph, in which a solid disk blocks the sun's bright face, revealing the sun's tenuous atmosphere, called the corona. 

Space-based coronagraphs are more widely used in space weather research because of their wide-field solar views that are not interrupted by cloud cover or Earth's rotation. 

But the new study showed that ground-based coronagraphs could improve the warning system.

​London, March 3 (IANS) Researchers have developed a new algorithm to identify the origin of irregular electrical 'storm waves' in the heart, a finding with major implications for the future treatment of a killer cardiac disease.

Atrial Fibrillation -- one of the most common forms of abnormal heart rhythm -- is caused by these waves and is a major cause of stroke as it increases the risk of blood clots forming inside the heart.

Current methods involve the use of a catheter to isolate the storm waves. However, this is very invasive surgery and it is extremely difficult to identify the origin of the waves in order to treat the condition, said researchers from UK's University of Manchester.

In the study, published in ther journal PLOS Computational Biology, researchers used a virtual human heart-torso and a 64-lead electrocardiogram (ECG) vest to study the correlation between the origin of the storm waves and the features of the ECG signals.

Using the properties of the atrial activation and the signals, they were able to develop a novel algorithm which could pin down the location of Atrial Fibrillation non-invasively, as well identifying different types of the condition.

"This technique can identify the origin of Atrial Fibrillation extremely effectively, which may provide a powerful tool for treatment in the future," said lead author Henggui Zhang, Professor at University of Manchester.

"The research, could lead to new developments to tackle heart problems more effectively and simply," Zhang added.

Atrial tachy-arrhythmias, including atrial fibrillation (AF), atrial tachycardia (AT) and flutter (AFL), are the most common cardiac arrhythmias, predisposing to heart attack, stroke and even possible cardiac death. 

Atrial fibrillation presents the greatest complexity and occurs in about 1-2 per cent of people and studies have shown that it is on the rise in the developed world due to the ageing population. 

London, March 3 (IANS) For the first time, scientists at the University of Cambridge have managed to create an artificial structure from stem cells that resembles a natural mouse embryo.

The findings could pave the way for developing artificial human life in the lab and help researchers understand why more than two out of three human pregnancies fail at the very early stages of embryo development.

Currently, embryos are developed from eggs donated through IVF clinics.

"We are very optimistic that this will allow us to study key events of this critical stage of human development without actually having to work on embryos. Knowing how development normally occurs will allow us to understand why it so often goes wrong," said lead researcher Magdalena Zernicka-Goetz, Professor at University of Cambridge.

For growing the mouse structure in culture, the researchers used two types of stem cells -- the body's 'master cells' -- and a 3D scaffold on which they can grow.

Previous attempts to grow embryo-like structures using only ESCs have had limited success.

This is because early embryo development requires the different types of cell to coordinate closely with each other.

However, in this study published in the journal Science, the researchers described how, using a combination of genetically-modified mouse embryonic stem cells and the extra-embryonic trophoblast stem cells, together with a 3D scaffold, they were able to grow a structure capable of assembling itself and whose development and architecture very closely resembled the natural embryo.

"Both the embryonic and extra-embryonic cells start to talk to each other and become organised into a structure that looks like and behaves like an embryo," Zernicka-Goetz said.

"It has anatomically correct regions that develop in the right place and at the right time," she added.

Comparing their artificial 'embryo' to a normally-developing embryo, the team was able to show that its development followed the same pattern of development. 

The stem cells organise themselves, with ESCs at one end and TSCs at the other. A cavity opens up within each cluster before joining together, eventually to become the large, so-called pro-amniotic cavity in which the embryo will develop, the researchers said. 

While this artificial embryo closely resembles the real thing, it is unlikely that it would develop further into a healthy foetus, the researchers said. 

To do so, it would likely need the third form of stem cell, which would allow the development of the yolk sac, which provides nourishment for the embryo and within which a network of blood vessel develops. 

In addition, the system has not been optimised for the correct development of the placenta, the researchers said.

Melbourne, March 2 (IANS) The brains of obese people could be "wired" to seek out fatty foods, Australian scientists have found.

Researchers from the Bio-Medicine Discovery Institute at Melbourne's Monash University are investigating the messaging system between the brain and the body with hopes of discovering the neurological cause of obesity, Xinhua news agency reported.

"There is no question the brain is the key site regulating appetite and obesity," associate professor Zane Andrews from Monash told Thursday.

"There are a number of genetic mutations that increase the risk of obesity and the majority are located somewhere in the brain."

Andrews said his focus was on brain cells responsible for sensing hunger that also influenced motivation and reward.

He said that early results indicated that the brains of obese people were not sending messages to tell the body that they already have enough energy stored.

Andrews' team has identified that part of the problem could form while the brain pathways are forming during childhood, with children who are rewarded for good behaviour with sweet treats, forming an association between sugar and feeling good.

The team has been able to delete an enzyme in mice that plays an important role in stopping the brain from sending messages that the body is still hungry.

"What we think is the problem in obesity is that those cells are not receiving or sensing the signals to say the person is full so they keep firing, causing people to continue eating," Andrews added.