Amazing Science

A team of researchers suggests that the forces controlling the strange behavior of black holes in space, is also applicable on cold helium atoms that can be studied in laboratories. Talking about the discovery Adrian Del Maestro, a physicist at the University of Vermont who co-led the research said. “It’s called an entanglement area law. He further added that this law appears at both the vast scale of outer space and at the tiny scale of atoms, “is weird,” and it points to a deeper understanding of reality.”

Both Black holes and superfluid are very strange: One is known for being so dense that light can’t escape and other is a weird liquid that flows without friction. The new findings was published in Journal Nature Physics on 13 March, 2017. To show the law in a superfluid, Christopher Herdman of the University of Waterloo in Canada and colleagues created a computer simulation of helium. The isotope they studied, helium-4, is the same one that we uses in balloons to keep them aloft, and it becomes a superfluid at temperatures below about 2 kelvins (–271° Celsius).

Undoubtedly, black holes are strange enough, but their relationship to entropy is something that celebrated physicist Stephen Hawking found himself particularly absorbed by. In 1970, Hawking along with Jacob Bekenstein calculated that when matter falls into one of these bottomless holes in space, the amount of information it gobbles up — what scientists call its entropy — increases only as fast as its surface area increases, not its volume. This would be like measuring how many files there are in a filing cabinet based on the surface area of the drawer rather than how deep the drawer is. As with many aspects of modern physics, check your common sense at the door.

“If you double the size of a box, you expect to be able to double the amount of information in that box,” says Christopher Herdman. That’s because the bigger a box, the more documents and other information can be stuffed inside. Progress toward a theory that unifies quantum mechanics and general relativity, a still thorny problem, has convinced many physicists that black holes follow this “area law.”

In the simulation, the researchers kept track of the helium atoms’ entanglement — quantum linkages that intertwine particles. Within the superfluid, scientists selected an imaginary sphere of the material, and studied the entanglement between atoms inside the sphere and those outside of it. That entanglement gives rise to a type of entropy in the superfluid. As the researchers increased the size of that sphere, the entropy of entanglement increased as well. The rate of increase matched that of the sphere’s increase in surface area, which grows more slowly than its volume.

In a research paper published in the Journal of Experimental Medicine, scientists report that Zika virus could be used to target and kill brain cancer stem cells, the kind of cells most resistant to standard treatments.

“We showed that Zika virus can kill the kind of glioblastoma cells that tend to be resistant to current treatments and lead to death,” said Michael S. Diamond, the Herbert S. Gasser Professor of Medicine at Washington University School of Medicine.

Each year in the United States, about 12,000 people are diagnosed with glioblastoma, the most common form of brain cancer. Among them is U.S. Sen. John McCain, who announced his diagnosis in July.

Just like normal, healthy tissues, the growth and development of glioblastomas is driven by stem cells that proliferate and give rise to other tumor cells.

Glioblastoma stem cells are hard to kill because they can avoid the body’s immune system and are resistant to chemotherapy and radiation. But killing these cells is vital to prevent new tumors from recurring after the original tumor has been surgically removed.

In their neurological origins and near-limitless ability to create new cells, glioblastoma stem cells reminded Professor Diamond and co-authors of neuroprogenitor cells, which generate cells for the growing brain. Zika virus specifically targets and kills neuroprogenitor cells.

The researchers tested whether the virus could kill stem cells in glioblastomas removed from patients at diagnosis. They infected tumors with one of two strains of Zika virus. Both strains spread through the tumors, infecting and killing the cancer stem cells while largely avoiding other tumor cells.

The findings suggest that Zika infection and chemotherapy-radiation treatment have complementary effects.

In the age of Big Data, it turns out that the largest, fastest growing data source lies within your cells. Quantitative biologists at the University of Illinois Urbana-Champaign and Cold Spring Harbor Laboratory, in New York, found that genomics reigns as champion over three of the biggest data domains around: astronomy, Twitter, and YouTube.

The scientists determined which would expand the fastest by evaluating acquisition, storage, distribution, and analysis of each set of data. Genomes are quantified by their chemical constructs, or base pairs. Genomics trumps other data generators because the genome sequencing rate doubles every seven months. If it maintains this rate, by 2020 more than one billion billion bases will be sequenced and stored per year, or 1 exabase. By 2025, researchers estimate the rate will be almost one zettabase, one trillion billion bases, per sequence per year. “What does it mean to have more genomes than people on the planet?”—Michael Schatz, Cold Spring Harbor Laboratory

90 percent of the genome data analyzed in the study was human. The scientists estimate that 100 million to 2 billion human genomes will be sequenced by 2025. That’s a four to five order of magnitude of growth in ten years, which far exceeds the other three data generators they studied. “For human genomics, which is the biggest driver of the whole field, the hope is that by sequencing many, many individuals, that knowledge will be obtained to help predict and cure a variety of diseases,” says University of Illinois Urbana-Champaign co-author, Gene Robinson. Before it can be useful for medicine, genomes must be coupled with other genomic data sets, including tissue information.

One reason the rate is doubling so quickly is because scientists have begun sequencing individual cells. Single-cell genome sequencing technology for cancer research can reveal mutated sequences and aid in diagnosis. Patients may have multiple single cells sequenced, and there could end up being more than 7 billion genomes sequenced.

That “is more than the population of the Earth,” says Michael Schatz, associate professor at Cold Spring Harbor Laboratory, in New York. “What does it mean to have more genomes than people on the planet?” What it means is a mountain of information must be collected, filed, and analyzed.

“Other disciplines have been really successful at these scales, like YouTube,” says Schatz. Today, YouTube users upload 300 hours of video every minute, and the researchers expect that rate to grow up to 1,700 hours per minute, or 2 exabytes of video data per year, by 2025. Google set up a seamless data-flowing infrastructure for YouTube. They provided really fast Internet, huge hard drive space, algorithms that optimized results, and a team of experienced researchers.

Thanks to Cassini’s new vantage point granted by its inclined orbit researchers have gotten a new look at the south pole of Titan, Saturn’s largest moon. What they’ve recently discovered is a swirling vortex of gas forming over the moon’s pole, likely the result of the approach of winter on Titan’s southern hemisphere.

What we’re seeing here is thought to be an open cell convection process in Titan’s upper atmosphere. In open cells, air sinks in the center of the cell and rises at the edge, forming clouds at cell edges. However, because the scientists can’t see the layer underneath the layer visible in these new images, they don’t know what other mechanisms may be at work.

A stable atmospheric event that’s found here on Earth as well, open cell convection can be compared to the action of boiling water.

Titan has already been seen to have a thicker area of high-altitude haze over its north pole, and as autumn progresses toward winter in Titan’s south during the course of Saturn’s 29.7-year-long orbit this may very well be the beginnings of a southern polar hood.

You’d think computers spend most of their time and energy doing, well, computation. But that’s not the case: about 90 percent of a computer’s execution time and electrical energy is spent transferring data between the processor and the memory banks, says Subhasish Mitra, a computer scientist at Stanford University. Even if Moore’s law continued on indefinitely, computers would still be limited by this memory bottleneck.

Recently, in the journal Nature, Mitra and collaborators describe a new computer architecture they say addresses this problem—and that Mitra believes will improve both the energy efficiency and speed of computers by a factor of 1000. The new 3D architecture is based on novel devices including 2 million carbon nanotube transistors and over 1 million resistive RAM cells, all built on top of a layer of silicon using existing fabrication methods and connected by densely packed metal wiring between the layers. As a demonstration, the team built an electronic nose that can sense and identify several common vapors including lemon juice, rubbing alcohol, vodka, wine, and beer.

These novel nanodevices are interesting in themselves, says Mitra, but computing’s problems will not be solved by switching out existing devices with new ones that are slightly better. He says the important thing about the combination of technologies in their prototype is that it enabled them to develop a new, more efficient architecture that would not be possible to make in traditional CMOS.

Stacking circuits is a way to bring memory and processing closer together, but even 3D chips have a significant memory bottleneck. They are typically limited by the number and quality of connections between levels. It’s not possible to build conventional metal interconnects on top of one layer and then add another level of memory or processing because of the temperatures required—in excess of 1000 degrees Celsius to make silicon devices.

Typically the layers are made separately, then bonded together and connected with relatively large, sparsely distributed connectors called through-silicon vias tens of micrometers apart, says Max Shulaker, a computer scientist at MIT. Shulaker worked with Mitra and Stanford electrical engineer H.-S. Philip Wong on the 3D nanosystem.

Molecules of vinyl cyanide reside in the atmosphere of Titan, Saturn's largest moon, says NASA.

Recent simulations have indicated that vinyl cyanide is the best candidate molecule for the formation of cell membranes/vesicle structures in Titan’s hydrocarbon-rich lakes and seas. Although the existence of vinyl cyanide (C2H3CN) on Titan was previously inferred using Cassini mass spectrometry, a definitive detection has been lacking until now. A team of scientists now report the first spectroscopic detection of vinyl cyanide in Titan’s atmosphere, obtained using archival data from the Atacama Large Millimeter/submillimeter Array (ALMA), collected from February to May 2014. They detect the three strongest rotational lines of C2H3CN in the frequency range of 230 to 232 GHz, each with >4σ confidence. Radiative transfer modeling suggests that most of the C2H3CN emission originates at altitudes of ≳200 km, in agreement with recent photochemical models. The vertical column densities implied by our best-fitting models lie in the range of 3.7 × 10^13 to 1.4 × 10^14 cm−2. The corresponding production rate of vinyl cyanide and its saturation mole fraction imply the availability of sufficient dissolved material to form ~10^7 cell membranes/cm^3 in Titan’s sea Ligeia Mare.

Buildings could soon be able to convert the sun's energy into electricity without the need for solar panels, thanks to innovative new technology.

Renewable Energy experts from the University of Exeter are developing a pioneering new technique that could accelerate the widespread introduction of net-zero energy buildings through the latest Building Integrated Photovoltaics (BIPV). These products, similar to the solar tile created by Tesla, can become a part of a building's architecture to generate electricity. The team have created an innovative glass block, which can be incorporated into the fabric of a building and is designed to collect solar energy and convert it to electricity.

It is thought that buildings consume more than forty percent of the electricity produced across the globe. This new technology would allow electricity to be produced at the site of use, whilst being seamlessly integrated into the building.

The blocks, called Solar Squared, are designed to fit seamlessly into either new buildings, or as part of renovations in existing properties. They are similar to existing glass blocks by allowing daylight to resonate around a property by replacing traditional bricks and mortar with transparent glass bricks.

Stanford University scientists have developed a high-tech mirror-like optical surface that uses “radiative sky cooling” to dramatically lower the energy required for air conditioning and refrigeration. The system cools water (flowing through pipes connected to an air-conditioning system) without requiring electricity by radiating excess heat from water into cold space. Panels covered in specialized optical surfaces reflect about 97 percent of the sunlight while simultaneously emitting the surface’s thermal energy through the atmosphere.

In a test on the roof of a Stanford University building, the panels were able to reduce the water temperature 3 to 5 degrees Celsius below ambient air temperature, allowing for a connected air conditioning system to lower its electricity use.

The researchers modeled a cooling system of a two-story commercial building in a hot dry climate (Las Vegas) with this panel-cooled system installed. They found it would save 14.3 megawatt-hours of electricity in the summer months — a 21 percent reduction in the electricity used to cool the building.

The system would also reduce the significant water loss in cooling systems using evaporative cooling.

As the researchers, led by Shanhui Fan, professor of electrical engineering, write in a paper published in Nature Energy Sept. 4, “cooling systems consume 15% of electricity generated globally and account for 10% of global greenhouse gas emissions.”

They note that “with demand for cooling expected to grow tenfold by 2050, improving the efficiency of cooling systems is a critical part of the twenty-first-century energy challenge.”

The researchers have founded the company SkyCool Systems, which is working on further testing and commercializing this technology. They are focused on making their panels integrate easily with standard air conditioning and refrigeration systems, and are especially interested in cooling data centers.

In treating brain cancer, time is of the essence. A new study, in which IBM Watson took just 10 minutes to analyze a brain-cancer patient’s genome and suggest a treatment plan, demonstrates the potential of artificially intelligent medicine to improve patient care. But although human experts took 160 hours to make a comparable plan, the study’s results weren’t a total victory of machine over humans.

The patient in question was a 76-year-old man who went to his doctor complaining of a headache and difficulty walking. A brain scan revealed a nasty glioblastoma tumor, which surgeons quickly operated on; the man then got three weeks of radiation therapy and started on a long course of chemotherapy. Despite the best care, he was dead within a year. While both Watson and the doctors analyzed the patient’s genome to suggest a treatment plan, by the time tissue samples from his surgery had been sequenced the patient had declined too far.

IBM has been outfitting Watson, its “cognitive computing” platform, to tackle multiple challenges in health care, including an effort to speed up drug discovery and several ways to help doctors with patient care. In this study, a collaboration with the New York Genome Center (NYGC), researchers employed a beta version of IBM Watson for Genomics.

IBM Watson’s key feature is its natural-language-processing abilities. This means Watson for Genomics can go through the 23 million journal articles currently in the medical literature, government listings of clinical trials, and other existing data sources without requiring someone to reformat the information and make it digestible. Other Watson initiatives have also given the system access to patients’ electronic health records, but those records weren’t included in this study.

Laxmi Parida, who leads the Watson for Genomics science team, explains that most cancer patients don’t have their entire genome (consisting of 3 billion units of DNA) scanned for mutations. Instead they typically do a “panel” test that looks only at a subset of genes that are known to play a role in cancer.

The new study, published in the journal Neurology Genetics, used the 76-year-old man’s case to answer two questions. First, the researchers wanted to know if scanning a patient’s whole genome, which is more expensive and time consuming than running a panel, provides information that is truly useful to doctors devising a treatment plan. “We were trying to answer the question, Is more really more?” says Parida.

The answer to that question was a resounding yes. Both the NYGC clinicians and Watson identified mutations in genes that weren’t checked in the panel test but which nonetheless suggested potentially beneficial drugs and clinical trials. 

For first time, scientists can peer deep into silicon to image atoms far from the surface without damaging the sample.

An international team of researchers has developed a nondestructive imaging technique that can peer deep inside of silicon to locate and characterize various structures. While this should be a boon for testing and measuring conventional silicon chips currently used in information processing, it could have its greatest impact by enabling the next generation of devices for quantum information processing.

In research described in the journal Science Advances, researchers from the University of Linz in Austria, University College London, ETH Zurich, and École Polytechnique Fédérale de Lausanne in Switzerland have adapted the well-established microscopy technique known as Scanning Microwave Microscopy (SMM) to identify dopants deep inside the silicon without causing any damage to the material. Dopants are atoms that are added to a semiconductor to change its electrical and optical properties.

SMM is used for a wide range of applications from characterizing biological cells to new materials, such as graphene, or standard semiconductor samples. It’s done by combing an Atomic Force Microscope (AFM)—which has a nanoscopic probe that’s scanned over the sample of interest—with a Vector Network Analyzer (VNA) that sends out a microwave signal from the AFM probe. The signal is reflected within the volume of the sample and measured by the VNA, which gives information about the three-dimensional structure and electrical properties of the sample.

The researchers used this SMM technique to image the electrical properties of a patterned layer of phosphorus atoms under a silicon surface. By using this technique, the researchers were able to image 1,900 to 4,200 densely packed atoms buried four to 15 nanometers below the surface. Of course, there other microscopy techniques like Secondary Ion Mass Spectrometry (SIMS) that can image these dopants. However, the main advantage of SMM is that it doesn’t modify or damage the sample.

“We see potentially a global impact with our technique for standard silicon chips, which are becoming so sophisticated and complex that taking snapshots of their smallest working parts is extremely difficult and time-consuming, and currently involves destroying the chip,” explained Georg Gramse, a post-doc at the University of Linz who led the research.

Researchers planted a working hacker exploit in a physical strand of DNA.

When biologists synthesize DNA, they take pains not to create or spread a dangerous stretch of genetic code that could be used to create a toxin or, worse, an infectious disease. But one group of biohackers has demonstrated how DNA can carry a less expected threat—one designed to infect not humans nor animals but computers.

In new research they plan to present at the USENIX Security conference on Thursday, a group of researchers from the University of Washington has shown for the first time that it’s possible to encode malicious software into physical strands of DNA, so that when a gene sequencer analyzes it the resulting data becomes a program that corrupts gene-sequencing software and takes control of the underlying computer. While that attack is far from practical for any real spy or criminal, it's one the researchers argue could become more likely over time, as DNA sequencing becomes more commonplace, powerful, and performed by third-party services on sensitive computer systems. And, perhaps more to the point for the cybersecurity community, it also represents an impressive, sci-fi feat of sheer hacker ingenuity.

“We know that if an adversary has control over the data a computer is processing, it can potentially take over that computer,” says Tadayoshi Kohno, the University of Washington computer science professor who led the project, comparing the technique to traditional hacker attacks that package malicious code in web pages or an email attachment. “That means when you’re looking at the security of computational biology systems, you’re not only thinking about the network connectivity and the USB drive and the user at the keyboard but also the information stored in the DNA they’re sequencing. It’s about considering a different class of threat.”

In the study, a research team led Kyoto University scientists aimed to investigate whether chimpanzees could learn a transverse pattern by being trained in the rules of the rock-paper-scissors game. “The relationship between the signals are non-linear and must be understood within the context of how the pairs are grouped,” the researchers explained.

“Learning such transverse patterns requires enhanced mental capacity. Being able to do so is useful when forming complex relationship networks, solving problems, or updating what you already know about a subject.” The study involved seven chimpanzees living in the Primate Research Institute at Kyoto University, Japan.

“The chimpanzees sat in a booth housing a computer-based touch screen and were trained to choose the stronger of two options (based on the rules of the game) they saw on screen,” the scientists said. “They first learnt the ‘paper-rock’ sequence, then the ‘rock-scissors’ one and finally ‘scissors-paper’.”

“Once they knew how the pairs fitted together, all the different pairs were randomly presented to them on screen. Five of the seven chimpanzees completed training after a mean of 307 sessions, which indicates that they learned the circular pattern. The chimpanzees required more ‘scissors-paper’ sessions, the third learnt pair, than ‘paper-rock’ and ‘rock-scissors’ sessions, suggesting they had difficulty finalizing the circularity.”

Having the correct number of chromosomes is vital for normal development and health. Sex chromosome trisomy (SCT) affects 0.1% of the human population and is associated with infertility. Scientists now show that during reprogramming to induced pluripotent stem cells (iPSC), fibroblasts from sterile trisomic XXY and XYY mice lose the extra sex chromosome, by a phenomenon we term trisomy-biased chromosome loss (TCL). Resulting euploid XY iPSCs can be differentiated into the male germ cell lineage and functional sperm that can be used in intracytoplasmic sperm injection to produce chromosomally normal, fertile offspring. Sex chromosome loss is comparatively infrequent during mouse XX and XY iPSC generation. TCL also applies to other chromosomes, generating euploid iPSCs from cells of a Down syndrome mouse model. It can also create euploid iPSCs from human trisomic patient fibroblasts. The findings have relevance to overcoming infertility and other trisomic phenotypes.

Scientists at the University of Oxford have developed a radical new method of 3D-printing laboratory-grown cells that can form complex living tissues and cartilage to potentially support, repair, or augment diseased and damaged areas of the body.

Printing high-resolution living tissues is currently difficult because the cells often move within printed structures and can collapse on themselves. So the team devised a new way to produce tissues in protective nanoliter droplets wrapped in a lipid (oil-compatible) coating that is assembled, layer-by-layer, into living cellular structures.

This new method improves the survival rate of the individual cells and allows for building each tissue one drop at a time to mimic the behaviors and functions of the human body. The patterned cellular constructs, once fully grown, can mimic or potentially enhance natural tissues.

“We were aiming to fabricate three-dimensional living tissues that could display the basic behaviors and physiology found in natural organisms,” explained Alexander Graham, PhD, lead author and 3D Bioprinting Scientist at OxSyBio (Oxford Synthetic Biology).

“To date, there are limited examples of printed tissues [that] have the complex cellular architecture of native tissues. Hence, we focused on designing a high-resolution cell printing platform, from relatively inexpensive components, that could be used to reproducibly produce artificial tissues with appropriate complexity from a range of cells, including stem cells.”

The researchers hope that with further development, the materials could have a wide impact on healthcare worldwide and bypass clinical animal testing. The scientists plan to develop new complementary printing techniques that allow for a wider range of living and hybrid materials, producing tissues at industrial scale.

New census calculates black hole populations in galaxies big and small.

The Milky Way teems with black holes — about 100 million of them. But there’s no reason to fear. “It may sound like a big number, but by astronomical standards, it’s a pretty small number,” says physicist Daniel Holz of the University of Chicago. The number of stars in the Milky Way, for example, is about a thousand times larger.

Scientists from the University of California, Irvine calculated the galaxy’s black hole population as part of a new census that estimates the numbers of cosmic chasms in galaxies big and small. The analysis, in press in Monthly Notices of the Royal Astronomical Society, quantified stellar-mass black holes, which form when a star collapses. Such objects can have masses tens of times that of the sun.

To draw up the celestial inventory, the researchers combined a variety of information about stars and galaxies. A star’s size and composition — the proportion of heavy elements it contains — determine whether it can form a black hole, and how big the black hole will be. And given a galaxy‘s size, scientists can estimate the number and properties of stars within, allowing researchers to deduce the number of black holes and their sizes.

Such stellar-mass black holes are a target of the Advanced Laser Interferometer Gravitational-Wave Observatory, LIGO, which has detected three sets of gravitational waves from colliding black holes (SN: 6/24/17, p. 6). When LIGO made its first detection, some physicists thought the coalescing black holes were surprisingly large; each was about 30 times the mass of the sun (SN: 3/5/16, p. 6). This puzzle led scientists to propose exotic origins for LIGO’s black holes — for example, that they formed during the universe’s infancy, instead of from collapsing stars (SN: 9/3/16, p. 8).