Science & Technology


DNA could be used to store data more efficiently than computers, scientists find

© Alamy
Internet pioneer Vint Cerf has warned of a 'digital dark age' descending as computer hardware and software becomes obsolete.
DNA could be used to store digital information and preserve essential knowledge for thousands of years, research has shown.

Scientists exploring the archiving potential of DNA conducted a test in which error-free data was downloaded after the equivalent of 2,000 years.

The next challenge is to find a way of searching for information encoded in strands of DNA floating in a drop of liquid.

Lead researcher Dr Robert Grass, from the Swiss Federal Institute of Technology (ETH), said: "If you go back to medieval times in Europe, we had monks writing in books to transmit information for the future, and some of those books still exist. Now, we save information on hard drives, which wear out in a few decades."

DNA has a "language" not unlike the binary code used in computers, said Dr Grass. While a hard drive uses zeros and ones to represent data, the DNA code is written in sequences of four chemical nucleotides, known as A,C,T and G.

But DNA can pack more information into a smaller space, and also has the advantage of durability.

In theory, a fraction of an ounce of DNA could store more than 300,000 terabytes of data, said Dr Grass. And archaeological finds had shown that DNA dating back hundreds of thousands of years can still be sequenced today.


Sweetgrass oil as effective as DEET in repelling mosquitoes

© Andrew Maxwell Phineas Jones, University of Guelph
Sweetgrass, a plant used in traditional medicine, contains compounds that can repel mosquitoes.
Native North Americans have long adorned themselves and their homes with fragrant sweetgrass (Hierochloe odorata), a native plant used in traditional medicine, to repel biting insects, and mosquitoes in particular. Now, researchers report that they have identified the compounds in sweetgrass that keep these bugs at bay.

The team will describe their approach in one of more than 9,000 presentations at the 250th National Meeting & Exposition of the American Chemical Society (ACS), the world's largest scientific society, taking place here through Thursday.

Mosquitoes and other insects remain a pesky part of everyday life in many parts of the world, and their bites are linked to a range of serious diseases, such as malaria. To add to the arsenal of insect repellents, Charles Cantrell, Ph.D., investigates the components of plants used in traditional therapies. "We found that in our search for new insect repellents, folk remedies have provided good leads."

Stock Down

Will humans survive the next mass extinction? Don't count on it!

© Dado Ruvic / Reuters
Death from above. In our future?
Despite populating vast swaths of the planet, and appropriating large amounts natural resources in order to survive, human beings are no more likely to survive a mass extinction event than rare or endangered species, scientists say.

A team from the University of Leeds examining the effects of mass extinctions found that widespread species, like humans, are just as likely to become extinct as less populous ones.

This contrasts with regular circumstances, where a populous species is more likely to survive than a rare or endangered one.

The team of scientists examined the fossil records of vertebrates from the Triassic and Jurassic periods - 252 to 145 million years ago. During this period a mass extinction thought to have been caused by a volcanic eruption wiped out almost 80 percent of all living species and gave rise to the dinosaurs.

Comment: Earth is long past due for its next 'shake-up'. And it's not just the current 'biodiversity crisis caused by human activity'; there is also the cosmic element to consider. In short, our survival is not something we can take for granted. And it is largely outside of our control. Who will take over when we're gone? Surely they'll do a better job with this planet than humanity ever did!


Study finds malaria parasites lose drug resistance following changes to health policies

© CC 2.5
Plasmodium sp., Errger der Malaria
Chloroquine (CQ) is a first-line treatment for Plasmodium falciparum infections, which like many other malaria treatments, eventually resulted in the selection of parasites with resistance to the drug. The evolutionary dynamics of antimalarial drug resistance are driven by many factors, including differing transmission contexts and new drug pressures on parasites. Recently, a group of researchers published a study in the Proceedings of the National Academy of Sciences that examined the loss of CQ resistance (CQR) in French Guiana following a health policy change.

To conduct their study, the researchers studied P. falciparum isolates collected between 1994 and 2013 from symptomatic patients in French Guiana. They conducted DNA extraction and phenotyping from samples to compile a database of genetic information about the various strains. Their analysis revealed the presence of a single mutation in the pfcrt allele encoding a substitution associated with a return of parasite susceptibility to CQ.

In 1995, CQ had become ineffective against the prevalent CQR parasite strains in much of French Guiana and surrounding countries, and was officially abandoned as a course of treatment because of poor clinical efficacy. Quinine plus doxycycline became the subsequent treatment through 2007. Researchers used a gene marker, K76T, as a marker for CQ resistance.

Comment: Also see:
Concerns have been raised as, twice before, resistance to the then gold standard anti-malarial drugs - chloroquine and sulfadoxine-pyrimethamine - started in the same region before spreading to South-east Asia and Africa, leading to the deaths of millions of children.

Experts warn millions of lives are at risk as world's most effective malaria drug loses its potency


Computer science: Mass extinctions can accelerate evolution

©, Credit: Joel Lehman
At the start of the simulation, a biped robot controlled by a computationally evolved brain stands upright on a 16 meter by 16 meter surface. The simulation proceeds until the robot falls or until 15 seconds have elapsed.
A computer science team at The University of Texas at Austin has found that robots evolve more quickly and efficiently after a virtual mass extinction modeled after real-life disasters such as the one that killed off the dinosaurs. Beyond its implications for artificial intelligence, the research supports the idea that mass extinctions actually speed up evolution by unleashing new creativity in adaptations.

Computer scientists Risto Miikkulainen and Joel Lehman co-authored the study published today in the journal PLOS One, which describes how simulations of mass extinctions promote novel features and abilities in surviving lineages.

"Focused destruction can lead to surprising outcomes," said Miikkulainen, a professor of computer science at UT Austin. "Sometimes you have to develop something that seems objectively worse in order to develop the tools you need to get better."

In biology, mass extinctions are known for being highly destructive, erasing a lot of genetic material from the tree of life. But some evolutionary biologists hypothesize that extinction events actually accelerate evolution by promoting those lineages that are the most evolvable, meaning ones that can quickly create useful new features and abilities.

Comment: We are seeing many species exiting the planet at this juncture in the evolution of our planet. This research suggests that not all life will become extinct; that what remains may experience a comparable and parallel acceleration in evolution befitting its future on Earth. If this is the sixth extinction, there will undoubtedly be a seventh and...


Supernovae found in 'wrong place at wrong time'

© NASA, ESA, and P. Jeffries and A. Feild (STScI)
This illustration offers a plausible scenario for how vagabond stars exploded as supernovae outside the cozy confines of galaxies. Panel 1: A pair of black holes comes together during a galaxy merger, dragging with them up to a million stars each. Panel 2: A double-star system wanders too close to the two black holes. Panel 3: The black holes then gravitationally catapult the stars out of the galaxy. At the same time, the stars are brought closer together. Panel 4: After getting booted out of the galaxy, the binary stars move even closer together as orbital energy is carried away from the duo in the form of gravitational waves. Panel 5: Eventually, the stars get close enough that one of them is ripped apart by tidal forces. Panel 6: As material from the dead star is quickly dumped onto the surviving star, a supernova occurs.
Several exploding stars have been found outside the cozy confines of galaxies, where most stars reside. These wayward supernovae are also weird because they exploded billions of years before their predicted detonations. Using archived observations from several telescopes, astronomers have developed a theory for where these doomed stars come from and how they arrived at their current homes. A new analysis of 13 supernovae -- including archived data from NASA's Hubble Space Telescope -- is helping astronomers explain how some young stars exploded sooner than expected, hurling them to a lonely place far from their host galaxies.

It's a complicated mystery of double-star systems, merging galaxies, and twin black holes that began in 2000 when the first such supernova was discovered, according to study leader Ryan Foley, University of Illinois at Urbana-Champaign. "This story has taken lots of twists and turns, and I was surprised every step of the way," he said. "We knew these stars had to be far from the source of their explosion as supernovae and wanted to find out how they arrived at their current homes."

Comment: When two black holes collide, it depends on the amount of hot gas surrounding each black hole. As they start to interact, this gas exerts a frictional force on the black holes, slowing down their spin rate. As the distance between them lessens, they begin emitting gravitational waves which continues to extract energy from the system. This causes them to continue coming together and eventually merge. The merger generates gravity waves detectable across space.

Blue Planet

Blue-green algae blooms increasingly threaten drinking water worldwide

© Oregon State University
Toxic Microcystis algae grow in a large bloom in the Copco Reservoir on the Klamath River, posing health risks to people, pets and wildlife.
A report concludes that blooms of toxic cyanobacteria, or blue-green algae, are a poorly monitored and underappreciated risk to recreational and drinking water quality in the United States, and may increasingly pose a global health threat.

Several factors are contributing to the concern. Temperatures and carbon dioxide levels have risen, many rivers have been dammed worldwide, and wastewater nutrients or agricultural fertilizers in various situations can cause problems in rivers, lakes and reservoirs.

No testing for cyanobacteria is mandated by state or federal drinking water regulators, according to scientists from Oregon State University, nor is reporting required of disease outbreaks associated with algal blooms. But changes in climate and land use, and even increasing toxicity of the bacteria themselves, may force greater attention to this issue in the future, the researchers said.


Corrupt science: How BigPharma stacks the deck to show their products work

© Tom Varco
Mark Zimmerman, M.D., a clinical researcher at Rhode Island Hospital, and his team analyzed the criteria used in antidepressant efficacy studies (AETs) and learned that the inclusion/exclusion criteria for AETs have narrowed over the past five years so that the most patients are excluded. The research was published today in Mayo Clinic Proceedings.

"The inclusion/exclusion criteria for AETs have narrowed over the past five years, thereby suggesting that AETs may be even less generalizable than they were previously," said Zimmerman, director of outpatient psychiatry and the partial hospital program at Rhode Island Hospital and director of the Rhode Island Methods to Improve Diagnostic Assessment and Services (MIDAS) project, a study that integrated researchers' assessment tools and procedures into a hospital-affiliated outpatient practice.

Comment: Independent studies have shown that there is little to no benefit from these medications and the side effects are substantial. But the profit potential is staggering, so the pharmaceutical industry routinely manages the data to prove their efficacy or simply refuses to publish when the results are not favorable to the drug or other product being tested.


NASA discovers 'smallest supermassive' black hole

© / NASA
Optical image of the RGG118 galaxy (center) and the X-ray image from Chandra (inset).
Just 50,000 times the mass of the Sun, a new supermassive singularity discovered by NASA is a tiny thing by cosmic standards. Scientists hope studying the black hole will help them learn more about the origins of the universe.

Using the orbiting Chandra X-ray observatory and the 6.5 meter Clay Telescope in Chile, astronomers found the black hole at the center of a dwarf disk galaxy, called RGG 118, some 340 million light years from Earth. The X-rays were produced by the hot gas swirling around the black hole.

"When gas rotates around a black hole, the motion causes the frequency of the light it emits to spread in a characteristic way. The width of this spread is related to the speed of rotation, which in turn is related to the mass of the black hole. By measuring the spread, we found that the black hole in RGG 118 weighs just 50,000 times the mass of the Sun, the smallest supermassive black hole yet reported!" wrote Vivienne Baldassare of the University of Michigan, lead author on the paper about the small supermassive black holes.


Mystery Deepens: Matter and antimatter are mirror images

© N. Kuroda
A newly reported experiment involving matter and antimatter was carried out in CERN's Antiproton Decelerator.
Matter and antimatter appear to be perfect mirror images of each other as far as anyone can see, scientists have discovered with unprecedented precision, foiling hope of solving the mystery as to why there is far more matter than antimatter in the universe.

Everyday matter is made up of protons, neutrons or electrons. These particles have counterparts known as antiparticles — antiprotons, antineutrons and positrons, respectively — that have the same mass but the opposite electric charge. (Although neutrons and antineutrons are both neutrally charged, they are each made of particles known as quarks that possess fractional electrical charges, and the charges of these quarks are equal and opposite to one another in neutrons and antineutrons.)

The known universe is composed of everyday matter. The profound mystery is, why the universe is not made up of equal parts antimatter, since the Big Bang that is thought to have created the universe 13.7 billion years ago produced equal amounts of both. And if matter and antimatter appear to be mirror images of each other in every respect save their electrical charge, there might not be much any of either type of matter left — matter and antimatter annihilate when they encounter each other.