Knowledge Update

​New York, April 16 (IANS) A team led by an Indian-origin engineer has built a camera prototype that can capture a detailed micron-resolution image from a distance and does that without using a long lens.

The prototype built and tested by engineers at US-based Rice and Northwestern universities uses a laser and techniques borrowed from holography, microscopy and "Matrix"-style bullet time.

It reads a spot illuminated by a laser and captures the "speckle" pattern with a camera sensor. 

Raw data from dozens of camera positions is fed to a computer programme that interprets it and constructs a high-resolution image.

The system known as SAVI -- "Synthetic Apertures for long-range, subdiffraction-limited Visible Imaging" -- only works with coherent illumination sources such as lasers.

"Today, the technology can be applied only to coherent (laser) light," said Ashok Veeraraghavan, a Rice University Assistant Professor of electrical and computer engineering, in a statement.

"That means you cannot apply these techniques to take pictures outdoors and improve resolution for sunlit images -- as yet. Our hope is that one day, maybe a decade from now, we will have that ability," he added.

The technology is the subject of an open-access paper in Science Advances.

Labs led by Veeraraghavan tested the device that compares interference patterns between multiple speckled images.

Veeraraghavan explained the speckles serve as reference beams and essentially replace one of the two beams used to create holograms. 

When a laser illuminates a rough surface, the viewer sees grain-like speckles in the dot. That's because some of the returning light scattered from points on the surface has farther to go and throws the collective wave out of phase. 

SAVI's "synthetic aperture" sidesteps the problem by replacing a long lens with a computer programme that resolves the speckle data into an image. 

"You can capture interference patterns from a fair distance. How far depends on how strong the laser is and how far away you can illuminate," Veeraraghavan added.

 

​New Delhi, April 15 (IANS) The number of people who are concerned about their security and are ready to protect themselves against cyberthreats has increased in the second half of 2016, Kaspersky Lab's updated index has revealed.

​New York, April 15 (IANS) US scientists have created a revolutionary digital three dimensional (3D) bio-printed patch that can help heal scarred heart tissue in patients after a heart attack.

During a heart attack, a person loses blood flow to the heart muscle, causing the cells to die. 

As the human body cannot replace those heart muscle cells so it forms scar tissue in that area of the heart, which puts the person at risk of compromised heart function and future heart failure, the study said.

Using laser-based 3D bio-printing techniques, the researchers led by the University of Minnesota, incorporated stem cells derived from adult human heart cells on a matrix that began to grow and beat synchronously in a dish in the lab.

When the cell patch was placed on a mouse following a simulated heart attack, the researchers saw significant increase in functional capacity after just four weeks. 

Since the patch was made from cells and structural proteins native to the heart, it became part of the heart and absorbed into the body, requiring no further surgeries.

"Given the complexity of the heart, we were encouraged to see that the cells had aligned in the scaffold and showed a continuous wave of electrical signal that moved across the patch," said Brenda Ogle, Associate Professor at the University of Minnesota in the US. 

The patch, modelled after a digital, 3D scan of the structural proteins of native heart tissue, is made into a physical structure by 3D printing with proteins native to the heart and further integrating cardiac cell types derived from stem cells, the researchers said, in the paper published in the journal Circulation Research.

"We feel that we could scale this up to repair hearts of larger animals and possibly even humans within the next several years," Ogle noted. 

​Santiago, April 15 (IANS) Nearly 300 million years ago, the frozen, inhospitable Antarctica was covered by lush subtropical forests, according to scientists.

"That Antarctica was once green is a matter of consensus among scientists, but still unknown to many people," Marcelo Leppe, a paleontologist who works with the Chilean Antarctic National Institute, told Efe news on Friday.

Leppe, Chile's representative to the international Scientific Committee on Antarctic Research, has spent his professional life searching for fossils that offer clues to the origins of the flora and fauna of the White Continent.

Forests began to appear in Antarctica some 298 million years ago during the Permian geologic period, as glaciers retreated and the global climate entered a warming phase, Leppe said.

Fossils from the subsequent Jurassic period reveal the existence of fern and conifer forests where the Cryolophosaurus species of dinosaur thrived.

But the golden age of vegetation in Antarctica was the Cretaceous period, which began 145 million years ago and lasted until around 66 million years ago.

"Roughly 80 million years ago, walking in Antarctica was like walking today in a tropical or subtropical forest, something like what we could encounter in south-central Chile or in New Zealand," Leppe said.

One thing that still puzzles scientists is how the forests survived the six-month-long Antarctic night.

"We know that some dinosaurs migrated before the arrival of winter, but in the case of plants, the matter continues to be an enigma," the paleontologist said.

While the plants would have received as much as 22 hours of light per day during the Antarctic summer, "that doesn't necessarily imply that they had the capacity to carry out photosynthesis for longer hours than now," he said.

The tundra that was the last vestige of the forests disappeared 15 million years ago, leaving Antarctica a frozen desert.

Now, however, scientists see grass and wild oats growing in the areas of Antarctica where the ice has retreated due to global warming, Leppe said.

Climate change, the introduction of invasive plants, and the retreat of the glaciers are creating the conditions for the White Continent to turn green again.

​San Francisco, April 14 (IANS) Aiming to secure a stable supply of memory chips for its iPhones, US tech giant Apple may invest billions of dollars to obtain a substantial stake in struggling Japanese conglomerate Toshiba's chip business, media reported on Friday.

New York, April 14 (IANS) Facebook's photo-sharing app Instagram has surpassed Snapchat in daily active users of "Stories" feature, though the format was first launched by Snapchat in 2013. According to a report in Forbes on Thursday, Instagram's "Stories" feature is now used by more than 200 million people every day -- an increase of 50 million since January. On the other hand, Snapchat who launched the "Stories" format in October 2013, had 161 million daily active users in February. "Stories" feature is an ephemeral chain of photo and video clips with filters and special effects. More recently, Facebook and WhatsApp also introduced the feature, imitating Snapchat. "Instagram Stories appears to have directly hampered Snapchat's user growth since its debut. Snapchat attributed its slowing pace in part to issues with Android updates and increasing competition. However, Instagram's impact on the chat app seems undeniable," the report noted. On May 10, the focus will be on Snapchat's user growth when Snap reports first quarter earnings.

​New York, April 14 (IANS) Google's digital wallet Android Pay is joining several banks around the world including Bank of America, Bank of New Zealand, Discover, mBank and USAA, to make it even easier for its users to pay with Android Pay.

​Shanghai, April 14 (IANS) The Brics New Development Bank (NDB) has planned to issue bonds twice this year, one denominated in Chinese yuan and the other in Indian rupee, bank's President K.V. Kamath said on Friday.

​New York, April 14 (IANS) Researchers have developed a diagnostic platform based on the gene editing tool CRISPR which could one day be used to respond to viral and bacterial outbreaks, monitor antibiotic resistance, and detect cancer.

The researchers adapted a CRISPR protein that targets RNA as a rapid, inexpensive, highly sensitive diagnostic tool.

The new tool, dubbed SHERLOCK (Specific High-sensitivity Enzymatic Reporter unLOCKing), can be designed for use as a paper-based test that does not require refrigeration.

It is well suited for fast deployment and widespread use inside and outside of traditional settings -- such as at a field hospital during an outbreak, or a rural clinic with limited access to advanced equipment, the researchers said.

"There is great excitement around this system," said study co-author Deborah Hung from Broad Institute of MIT and Harvard in in Cambridge, Massachusetts, US.

"There is still much work to be done, but if SHERLOCK can be developed to its full potential it could fundamentally change the diagnosis of common and emerging infectious diseases," Hung said.

In a study published in the journal Science, the researchers described how this RNA-targetting CRISPR enzyme, Cas13a, was harnessed as a highly sensitive detector -- able to indicate the presence of as little as a single molecule of a target RNA or DNA molecule. 

The scientists demonstrated the method's versatility on a range of applications, including detecting the presence of Zika virus in patient blood or urine samples within hours, and rapidly reading human genetic information, such as risk of heart disease, from a saliva sample.

"We can now effectively and readily make sensors for any nucleic acid, which is incredibly powerful when you think of diagnostics and research applications," said Jim Collins, Professor of Bioengineering at MIT, and faculty member at the Wyss Institute for Biologically Inspired Engineering at Harvard. 

"This tool offers the sensitivity that could detect an extremely small amount of cancer DNA in a patient's blood sample, for example, which would help researchers understand how cancer mutates over time," Collins said.

​New York, April 14 (IANS) Exposure to higher levels of air pollution may increase cardiovascular disease risk by lowering levels of high-density lipoprotein (HDL), commonly known as "good" cholesterol, says a study.

Higher exposure to black carbon, a marker of traffic-related pollution, is significantly associated with a lower "good" cholesterol level, showed the findings published in the journal Arteriosclerosis, Thrombosis, and Vascular Biology.

The lower levels of HDL observed with high levels of air pollution "may put individuals at a higher risk for cardiovascular disease down the line," said lead author Griffith Bell from the University of Washington School of Public Health in Seattle.

In the study of 6,654 middle-aged and older US adults from diverse ethnic backgrounds, participants living in areas with high levels of traffic-related air pollution tended to have lower HDL levels.

Higher particulate matter exposure over three months was associated with a lower HDL particle number, the researchers said. 

Changes in HDL levels may already appear after brief and medium-length exposures to air pollution, the authors noted.

Men and women responded to air pollutants differently. While HDL was lower at higher pollution exposure for both sexes, but the magnitude was greater in women.

The findings are part of the Multi-Ethnic Study of Atherosclerosis, an ongoing US study examining the lifestyle factors that predict development of cardiovascular disease.