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Man itself is the largest Technology's Museum  ( Rana Muhammad Imran Khan  Editor)

 
NASA Radar Demonstrates Ability to Foresee Sinkholes

New analyses of NASA airborne radar data collected in 2012 reveal the radar detected indications of a huge sinkhole before it collapsed and forced evacuations near Bayou Corne, La. that year.

The findings suggest such radar data, if collected routinely from airborne systems or satellites, could at least in some cases foresee sinkholes before they happen, decreasing danger to people and property.

Sinkholes are depressions in the ground formed when Earth surface layers collapse into caverns below. They usually form without warning. The data were collected as part of an ongoing NASA campaign to monitor sinking of the ground along the Louisiana Gulf Coast.

Researchers Cathleen Jones and Ron Blom of NASA's Jet Propulsion Laboratory (JPL) in Pasadena, Calif., analyzed interferometric synthetic aperture radar (InSAR) imagery of the area acquired during flights of the agency's Uninhabited Airborne Vehicle Synthetic Aperture Radar (UAVSAR), which uses a C-20A jet, in June 2011 and July 2012. InSAR detects and measures very subtle deformations in Earth's surface.

Their analyses showed the ground surface layer deformed significantly at least a month before the collapse, moving mostly horizontally up to 10.2 inches (260 millimeters) toward where the sinkhole would later form. These precursory surface movements covered a much larger area -- about 1,640 by 1,640 feet, (500 by 500 meters) -- than that of the initial sinkhole, which measured about 2 acres (1 hectare).

Results of the study are published in the February issue of the journal Geology.

"While horizontal surface deformations had not previously been considered a signature of sinkholes, the new study shows they can precede sinkhole formation well in advance," said Jones. "This kind of movement may be more common than previously thought, particularly in areas with loose soil near the surface."

The Bayou Corne sinkhole formed unexpectedly Aug. 3, 2012, after weeks of minor earthquakes and bubbling natural gas that provoked community concern. It was caused by the collapse of a sidewall of an underground storage cavity connected to a nearby well operated by Texas Brine Company and owned by Occidental Petroleum. On-site investigation revealed the storage cavity, located more than 3,000 feet (914 meters) underground, had been mined closer to the edge of the subterranean Napoleonville salt dome than thought. The sinkhole, which filled with slurry --a fluid mixture of water and pulverized solids-- has gradually expanded and now measures about 25 acres (10.1 hectares) and is at least 750 feet (229 meters) deep. It is still growing.

"Our work shows radar remote sensing could offer a monitoring technique for identifying at least some sinkholes before their surface collapse, and could be of particular use to the petroleum industry for monitoring operations in salt domes," said Blom. "Salt domes are dome-shaped structures in sedimentary rocks that form where large masses of salt are forced upward. By measuring strain on Earth's surface, this capability can reduce risks and provide quantitative information that can be used to predict a sinkhole's size and growth rate."

Typically, sinkholes have no natural external surface drainage, and they form through natural processes and human activities. They occur in regions of "karst" terrain where the rock below the surface can be dissolved by groundwater, most commonly in areas with limestone or other carbonate rocks, gypsum, or salt beds. When the rocks dissolve, they form spaces and caverns underground. Sinkholes vary in size from a few feet across to hundreds of acres, and some can be very deep. They are common hazards worldwide and are found in all regions of the United States, with Florida, Missouri, Texas, Alabama, Kentucky, Tennessee and Pennsylvania reporting the most sinkhole damage. While sinkhole deaths are rare, in February 2013 a man in Tampa, Fla., was killed when his house was swallowed by a sinkhole.

The human-produced Bayou Corne sinkhole occurred in an area not prone to sinkholes. The Gulf Coast of Louisiana and eastern Texas sits on an ancient ocean floor with salt layers that form domes as the lower-density salt rises. The Napoleonville salt dome underneath Bayou Corne extends to within 690 feet (210 meters) of the surface. Various companies mine caverns in the dome by dissolving the salt to obtain brine and subsequently store fuels and salt water in the caverns.

Jones and Blom say continued UAVSAR monitoring of the area as recently as October 2013 has shown a widening area of deformation, with the potential to affect other nearby storage cavities located near the salt dome's outer wall. Because the Bayou Corne sinkhole is now filled with water, it is harder to measure deformation of the area using InSAR. However, if the deformation extends far past the sinkhole boundaries, InSAR could continue to track surface movement caused by changes below the surface.

Continued growth of the sinkhole threatens the community and Highway 70, so there is a pressing need for reliable estimates of how fast it may expand and how big it may eventually get.

"This kind of data could be of great value in determining the direction in which the sinkhole is likely to expand," said Jones. "At Bayou Corne, it appears that material is continuing to flow into the huge cavern that is undergoing collapse."

Blom says there are no immediate plans to fly UAVSAR over sinkhole-prone areas.

"You could spend a lot of time flying and processing data without capturing a sinkhole," he said. "Our discovery at Bayou Corne was really serendipitous. But it does demonstrate one of the expected benefits of an InSAR satellite that would image wide areas frequently.

"Every year, unexpected ground motions from sinkholes, landslides and levee failures cost millions of dollars and many lives," said Jones. "When there is small movement prior to a catastrophic collapse, such subtle precursory clues can be detected by InSAR."

NASA monitors Earth's vital signs from land, air and space with a fleet of satellites and ambitious airborne and ground-based observation campaigns. NASA develops new ways to observe and study Earth's interconnected natural systems with long-term data records and computer analysis tools to better see how our planet is changing. The agency shares this unique knowledge with the global community and works with institutions in the United States and around the world that contribute to understanding and protecting our home planet.

Published on 7th March, 2014  www.dawnpost.com


Payload preparations begin for Arianespace’s upcoming Soyuz mission with Sentinel-1A

The first spacecraft for Europe’s Copernicus Earth observation program – Sentinel-1A – is now undergoing pre-launch checkout at the Spaceport, readying it for an April 3 liftoff on Arianespace’s next Soyuz flight from French Guiana.

Sentinel-1A is being put through its paces inside the Spaceport’s S1A payload preparation facility, where the radar satellite was transported following this week’s arrival in French Guiana aboard an An-124 cargo jetliner.

During the initial preparations, Sentinel-1A was removed from its shipping container in clean room conditions, then raised to a vertical position for the start-up of processing. 

Sentinel-1A is to deliver essential data for Copernicus, a European Space Agency (ESA) program in partnership with the European Commission – which will create a sustainable European satellite network to collect and evaluate environmental data for civil safety and humanitarian purposes.

Specifically, Sentinel-1A was designed and built by Thales Alenia Space for environmental tasks that include maritime surveillance and monitoring of sea ice, oil spills, landslides and floods. These tasks will assist in reconnaissance and operational support activities in response to natural disasters, for which the latest data is required as rapidly as possible.

The Sentinel-1B “sister” satellite will be launched a few years after Sentinel-1A, to improve revisit intervals and allow the entire planet’s mapping in only six days. Both spacecraft are based on the Prima platform developed by Thales Alenia Space on behalf of the Italian space agency, and carry a C-band SAR (Synthetic Aperture Radar) radar instrument developed by Airbus Defence and Space that allows Earth imaging through cloud and rain, in day or night conditions.

Sentinel programs being developed by ESA within the scope of Copernicus include five satellite families: Sentinel-1, designed to ensure the continuity of ERS and Envisat radar data; Sentinel-2 and -3, dedicated to Earth and ocean monitoring; and Sentinel-4 and -5, for meteorology and climatology, with a focus on studying the Earth atmosphere's composition.

This upcoming launch will mark Arianespace’s seventh Soyuz mission from Europe’s Spaceport since the medium-lift vehicle’s 2011 introduction, as well as the company’s third overall flight conducted from the equatorial launch site in 2014.

Published on 7th March, 2014  www.dawnpost.com


Gene therapy shows promise for HIV control without drugs: study

U.S. researchers said Wednesday they have used gene therapy involving genetically engineered T- cells to successfully decrease the amount of the AIDS virus in several patients taken off antiretroviral drug therapy (ADT) entirely, including one patient whose levels became undetectable.

The study, published in the U.S. journal New England Journal of Medicine, is the first published report of any gene editing approach in humans, the researchers said.

"This study shows that we can safely and effectively engineer an HIV patient's own T cells to mimic a naturally occurring resistance to the virus, infuse those engineered cells, have them persist in the body, and potentially keep viral loads at bay without the use of drugs," senior author Carl June, professor of the University of Pennsylvania, said in a statement.

"This reinforces our belief that modified T cells are the key that could eliminate the need for lifelong ADT and potentially lead to functionally curative approaches for HIV/AIDS," June said.

In their study, the researchers used a technology called the zinc finger nuclease (ZFN) to modify the T cells in 12 patients with the AIDS virus in order to mimic the CCR5-delta-32 mutation that can provide a natural HIV resistance. Only one percent of the general population carries that rare mutation.

They then infused the modified cells known as SB-728-T into two groups of patients, all treated with single infusions of about 10 billion cells, between May 2009 and July 2012.

Six were taken off antiretroviral therapy altogether for up to 12 weeks, beginning four weeks after infusion, while six patients remained on treatment.

The researchers found that the amount of HIV dropped in four patients whose treatment was interrupted for 12 weeks.

One of those patients' viral loads dropped below the limit of detection before reinstitution of ADT and the patient was later found to be "heterozygous" for the CCR5-delta-32 gene mutation, they said.

"This case gives us a better understanding of the mutation and the body's response to the therapy, opening up another door for study," co-author Bruce Levine, associate professor of the University of Pennsylvania said.

Therapies based on the CCR5 mutation have gained steam over the last six years, particularly after a man known as the Berlin Patient was "functionally" cured. Diagnosed with acute myeloid leukemia, the man received a stem cell transplant from a donor who had the CCR5 mutation and has remained off ADT since 2008.

Published on 7th March, 2014  www.dawnpost.com


Now belt will save lives during Earth Quakes

A cheap and easily implemented technology developed at a UK university could help save lives in earthquakes and make houses safe to live in after disaster has struck. It's as simple as buckling up.
 

More than a thousand deaths could be prevented every year if buildings were made to withstand earthquakes. But so far few developing countries have had access to the often expensive and complicated technology needed to make buildings earthquake-proof.

Now a team at the University of Sheffield in the UK has applied a new technique in tests where a full-size concrete building was subjected to similar forces as those seen in the devastating 2010 Haiti earthquake - without it collapsing.

Strapping metal belts tightly around a building's concrete columns kept the material from cracking and collapsing under strain during the tests.

"The strapping works very much like a weightlifter's belt, by keeping everything tightly compressed to reduce tension on the concrete columns of the structure," says Professor Kypros Pilakoutas, who has been heading the research team in Sheffield.

"The column is constantly confined under lateral pressure, so when there is seismic loading the concrete is not going to open up and crack and fail," Professor Pilakoutas says.
 

The tests, published in the Journal of Earthquake Engineering, involved putting a concrete structure through a simulated earthquake on a specially constructed seismic table, which shakes back and forth like the ground during a quake. When reinforced with the metal belts, the concrete would still sway back and forth, but never collapse.

"Our method not only makes the building stable again very quickly, but it increases the building's ability to deform without breaking, making it more able to withstand further earthquake movement," he says.

Making damaged or partially collapsed homes safe in the event of aftershocks would allow people to move back in much quicker. That would take away many of the risks to health associated with displaced populations.

Only two people would be needed to secure a simple dwelling in a matter of hours, and the Sheffield researchers estimate the cost per house to be around 250 euros ($343).
"The most common cause is simply buildings falling on them," says Christine Casser. Casser travelled to Bohol as a rescue volunteer on behalf of Disaster Aid UK, a Rotary International-linked aid and rescue organization.
 

Casser says she welcomes solutions such as the one developed by the University of Sheffield to make houses safe in earthquake areas.

"It's absolutely vital, that's the only way you can safeguard people's lives," says Casser. "One of the challenges we had was getting aid to the communities that were badly hit, because all the bridges had been destroyed. So if these techniques could be used to reinforce bridges, then that would mean more aid could get through faster - you are literally talking about saving people's lives."

Earthquake-prone regions in the developed world, such as Tokyo and California, have invested heavily in protecting new and old buildings from seismic activity.

By contrast, developing countries often fail to prepare for earthquakes mainly for two reasons: a lack of money and a tendency to forget too soon.

"We still see some damaged buildings in Mexico City. But people just forget how fragile these buildings are," says Reyes Garcia, a Mexican PhD student working alongside Professor Pilakoutas at the University of Sheffield. Mexico City was hit by a magnitude 8.1 earthquake in 1985. The quake killed more than ten thousand people.

Posted on 28th Feb, 2014     www.dawnpost.com


 

Building a sustainable smart phone out of blocks

When Dave Hakkens' camera stopped working because of a defective part, he couldn't get it repaired. It wasn't possible to replace the part, even though the rest of the device still worked just fine.

This so maddened Hakkens that he decided to revolutionize the electronics world. For his final-year project at the Design Academy Eindhoven in the Netherlands he came up with a project aimed at changing how consumers interact with electronics.

Repairing products instead of buying new ones - that's Hakkens' vision. However, the design concept he developed isn't for cameras: It's for smart phones. His phone can be assembled out of several modules, like pieces of Lego - a block for the screen, a block for the battery, another block for the camera. And depending on repair needs, and what the consumer wants, the blocks can simply be expanded or exchanged. Hakkens named his concept Phonebloks.

Daniel Basa, a computer scientist at Bielefeld University in Germany, says it's already possible to manufacture a cellphone like this: "But it doesn't make sense technically," he maintains.

Basa says that flexible modules require longer electronic connections, which would make the phone slower. Also, if every module requires its own casing, the phone would be thicker, heavier and larger.

It would also be more expensive. Manufacturers get the individual parts cheaper because they buy in bulk. With Phonebloks, the manufacturers require far fewer parts, and that would increase the price.

Despite this, Dave Hakkens' idea seems to have captured the zeitgeist. The YouTube video in which he explained how the phone works garnered more than more a million clicks within just 24 hours.

Hakkens had planned to publish the video after a holiday in Greece at the end of last summer, but it was leaked while he was still on the beach. With hours, he had received hundreds of emails and calls, all of which he answered in his swimming trunks. "I wasn't expecting that," he says.

It's now more than three months since it was published, and the video has been viewed more than 18.5 million times - a massive success.

ut Hakkens wanted to reach even more people, and appealed for people to support his idea by sharing it on social networks. He doesn't plan to manufacture Phonebloks himself. "It's a vision," he explained. "It's about showing companies that lots of people want a phone like this. They have to create one!"

By the end of October, more than 900,000 people around the world had shared Hakkens' idea. The numbers succeeded in impressing phone companies - including Motorola. Thirty years ago, the US-based firm created one of the very first cellphones. In 2012, Motorola was bought by Google.

Now Motorola and Hakkens have teamed up to work on a commercially-viable cellphone - together with the Phonebloks online community. Ideas are exchanged and developed on an online platform, which is also used to communicate the current status of the project. Motorola wants to use the eco-friendly idea in order to re-establish itself as a major smart phone manufacturer.

Posted on 28th Feb, 2014     www.dawnpost.com

 

Black holes blow stronger winds than previously thought: study

Black holes can release more energy into the galaxies they live in than previously thought, a new study said Thursday.

The discovery, published in the U.S. journal Science, will help astronomers better model the evolution of black holes over time, and it will also help them better understand how these mysterious regions affect their host galaxies.

Black holes are places in space where gravity pulls so much that even light cannot get out.

Black holes grow when gas in space flows or accretes onto them. The gas inside gets so hot it emits radiation.

According to a theory of physics called the Eddington limit, the amount of radiation flowing outward from a black hole cannot exceed a certain limit or it will blow the inflowing gas away. The limit is based on the black hole's mass.

However, whether a black hole's kinetic energy, in the form of jets and winds, is controlled by the same limit has been unclear.

To shed some light on the matter, scientists led by Roberto Soria of Australia's Curtin University used telescopes to study the outflow of a black hole in galaxy M83 for more than a year.

By analyzing the gas flowing into the black hole, they figured out the black hole's weight as less than 100 times that of the Sun.

The researchers compared the mass of the black hole with its outgoing kinetic power, which they were able to infer in part by looking at the light around it.

The kinetic power flowing out of the black hole was higher than the Eddington limit for a black hole of this mass, the researchers found.

These results demonstrate that black holes can "inject more energy into the surrounding medium than would be inferred based on their Eddington limits," the researchers wrote in their paper.

"The existence of super-Eddington mechanical power is important for the modeling of jet production mechanisms, as well as the evolution of fast-growing supermassive BHs (black holes) in the early universe, and their effect on their host galaxies," they added.

Posted on 28th Feb, 2014     www.dawnpost.com

Man itself is the largest Technology Museum  (Rana Muhammad Imran Khan)