All posts by Daniel

How Migratory Birds Know Their Longitude

The calculation of longitude was one of the great scientific challenges of the 18th century. Very valuable prizes were offered for its solution, while countless sailors died from the delay. Yet birds solved the problem millions of years ago. Their solution, at least for reed warblers, has now been revealed as measuring magnetic declination – the angle between magnetic north and true north – as well as the more widely used intensity and inclination.

Calculating latitude is a relatively easy task, since (much to the annoyance of flat earthers) different stars can be seen depending on the distance from the equator. Longitude is much harder, and prior to GPS required very accurate clocks that could compare local time with that at a known location.

As a new paper in Current Biology notes: “Birds do not appear to possess a time-difference clock sense.” Despite this, some manage to go on east-west migrations, as well as the more common north-south ones, homing in on specific sites. Moreover, the paper says “Night-migratory songbirds can correct for east-west displacements to unknown locations.”

The authors caught 15 reed warblers (Acrocephalus scirpaceus) in western Russia on their way to Africa. These were placed inside a magnetic field with the same strength as that of the Earth locally, but a declination differing by 8.5 degrees. The artificial field mimicked that near Edinburgh. The birds responded as if they were indeed now in Scotland, turning 151º to fly east-south-east, rather than west-south-west.

Reed warnbler’s breeding grounds (yellow) the path of migration for those from the eastern Baltic, lines of common magnetic declination (red) and common magnetic intensity (blue). Chernetsov et al/Current Biology

 “We’ve shown for the first time that magnetic declination may be a component of the magnetic navigational map, at least in some long-distance migratory birds,” said Dr Nikita Chernetsov of the Zoological Institute of the Russian Academy of Sciences, in a statement.

The research also revealed a learned component. Twenty-five birds too young to have undergone a migration through Western Europe became confused on exposure to the altered field, trying to fly in random directions.

“Reed warblers seem to learn the large-scale spatial pattern of the declination gradient during their annual movements, just like they learn other gradients, inclination, and total intensity,” Chernetsov said. “As magnetic declination mainly varies along the east-west axis, it provides the possibility to measure longitude.”

Unresolved questions include how reed warblers understand the implications of a gradient from a location they have never experienced, and whether all migratory birds use the same technique. The discovery could have been of great use to navigators in previous centuries, who might have found compasses that could measure magnetic declination easier to build than clocks that would keep time on a rolling ship. Nevertheless, it is not clear if there are any technological applications for which it could be used today.

Adult reed warblers responded to a different magnetic declination as if they were in Scotland. Juveniles didn’t know where they were and tried to fly in random directions. Ekaterina Chernetsova



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We’ll Survive 2012 Apocalypse, So Will Doomsday Fears


Humanity will survive the supposed December 2012 apocalypse, but, unfortunately, so will irrational doomsday fears, scientists say.

Doomsayers around the world are gearing up for armageddon on Dec. 21, based on predictions supposedly made by the Mayans more than 1,000 years ago. Even after the sun rises Dec. 22, however, many folks will be only momentarily reassured, quickly latching onto another scenario purported to bring about the apocalypse within their lifetime.

The persistence of these worries stems from a variety of factors, researchers say. The deluge of misinformation on the Internet, poorly developed or underutilized critical thinking skills and plain old human nature all contribute, convincing many people to fear the worst despite the lack of compelling evidence (and the poor track record of such dire predictions over the years).

“There have been end-of-the-world predictions every few years throughout history, really,” said astronomer David Morrison, head of the Carl Sagan Center for the Study of Life in the Universe at the SETI (Search for Extraterrestrial Intelligence) Institute in Mountain View, Calif. “We had two or three last year.”

Morrison spoke at the SETICon 2 conference in Santa Clara, Calif., on June 23 during a panel discussion called “Cosmophobia: Doomsday 2012 and Other Fiction Science.” [Don’t Panic: 2012 Doomsday Fears Debunked]

Flood of Misinformation

Though Morrison and other scientists work hard to tamp down fears of Comet Elenin, the mythical planet Nibiru and other supposed agents of impending doom, their voices of reason have a hard time being heard these days.

“We are completely drowned out by the doomsayers on the Internet,” Morrison said. “It’s very hard for the truth to even get a hearing.”

It’s especially hard to reach young people, most of whom seem unable to distinguish between reliable and unreliable sources, he added.

“At the best, they will just count numbers,” Morrison said. “‘Well, there are 83 websites that say the world will end in 2012, and one that says it won’t. So it must be true.'”

Not all of the misinformation is coming from altruistic folks who just want to get the worried word out, said fellow panelist Andrew Fraknoi, chair of the astronomy department at Foothill College in Los Altos Hills, Calif. Some of it is probably pumped out by people trying to make a buck.

“Today, it seems like money is much more important than truth, that anything goes,” Fraknoi said. “Fear-mongering has become a large and profitable industry.”

Data from the publishing world appear to back him up: A search for “Doomsday 2012” books on returns nearly 200 titles.

It’s Human Nature

But not all of the blame can be laid at the Internet’s feet. Doomsday fears have cropped up repeatedly throughout history, and in most cases they weren’t sustained by YouTube videos and “Nibiru” Google searches. [Oops! 11 Failed Doomsday Predictions]

The Millerites, for example, believed that Jesus Christ would return to Earth in 1843 or 1844, and that the world as we know it would be destroyed in the process. Another group called the Seekers thought a huge flood would ravage our planet on Dec. 21, 1954. The Seekers’ leader, a Chicago woman named Dorothy Martin, claimed to have gotten this information from aliens living on the planet Clarion.

We shouldn’t be too surprised whenever such cults grab the headlines, said Leonard Mlodinow, a Caltech physicist and author of such books as “The Drunkard’s Walk: How Randonmness Rules Our Lives” and “The Grand Design” (which he wrote with Stephen Hawking).

“I think it’s a very natural human phenomenon,” Mlodninow said. “People who we consider very rational believe such things all the time.”

He cited today’s major religions, saying that they would have seemed just as odd and irrational as the doomsday cults if we’d encountered them back in the early days, before they became so well established.

“I don’t consider those people particularly weird,” Mlodinow said of modern doomsayers. “I just think that they’re early adopters, you might call them.”

There’s likely some ego-boosting pyschology involved as well, said panelist Seth Shostak, a senior astronomer at the SETI Institute.

“To some extent, it’s a very empowering thought — that you know something very important that those nerdy, pointy-headed, tweed-jacketed academics down at the local university won’t acknowledge,” Shostak said. “I think you have to look for the answers there.”

Is Education the Answer?

Whatever their causes, doomsday fears are quite prevalent in the United States and abroad.

For example, a poll commisioned by the news agency Reuters earlier this year found that 15% of people worldwide — or roughy 1 billion folks — believe the apocalypse will come during their lifetime. In the United States, the figure is 22%.

Such worries aren’t just interesting sociological or psychological phenomena, Morrison said. They can have tragic consequences for believers.

“At least once a week, I get a question from a young person — usually 11, 12 years old — who says they are contemplating suicide before the end of the world,” Morrison said. “I know of several cases at least of reported suicides, of people who are obsessed with the end of the world in 2012.”

The best way to combat irrational doomsday worries — especially among the young — is education, Fraknoi said. We need to teach better critical thinking skills and instill a love of discovery that will inspire kids to seek out the truth — and make them less likely to be gulled by fanciful rumors.

“Ask yourself the question, ‘Why should I believe a word of this?'” Fraknoi said. “If you know how to answer, ‘Why should I believe a word of this?’ then you’re much closer to scientific truth.”

Artist’s conception of the rogue planet Nibiru, or Planet X courtesy of gilderm,

This article originally published at

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Oculus Rift Unveils New Virtual Reality Headset for Devs to Play With


The second generation Oculus Rift will be available for game developers this summer.

Game developers interested in creating games in virtual reality will get an upgraded set of tools from the Oculus Rift team this summer, the company announced Wednesday morning.

The second-generation Oculus Rift development kit is available for preorder starting Wednesday for developers. The virtual reality headset, which began as a Kickstarter campaign in 2012, now has 50,000 units in the hands of developers interested in creating games for it.

Oculus VR Vice President of Product Nate Mitchell said doesn’t resemble anything like consumers will eventually see, but is much farther along the company’s vision for virtual reality than the previous Oculus Rift model. A consumer version is still not under discussion, he added.

“We’ve learned a lot of lessons from our original vision,” Mitchell said.

The new Oculus Rift headset solves many users’ latency issues; it eliminates the motion blur problems that were easy to spot if you moved your head too quickly. It features a brighter, higher-resolution OLED screen with a 960 x 1080p resolution over each eye, rather than a 640 x 800p resolution over each eye on the current kit.


A straight on view of the updated Oculus Rift.

The new headset also boasts improved positional tracking, part of the Crystal Cove prototype the company showed off during CES 2014. Mitchell said that such new features will allow developers to bring many more complex elements into games they produce for virtual reality, including text and UI layouts. Previously, both were previously very difficult to add.

The new headset will cost $350 for developers and will ship sometime in July of this year.

Virtual reality may be the belle of the ball at the Game Developers Conference this week. Sony also used the conference to announce its own virtual reality headset for the PlayStation 4, currently called Project Morpheus. Sony remained mum on setting a date for its headset to reach consumers.

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From Washing Machines To Computers: How The Ancients Invented The Modern World

True innovation is hard to find, as few things come out of nothing. Take the now ubiquitous selfie, for example. The format may have changed but the concept of making self-portraits is hundreds, if not thousands of years old. The same is true of many inventions that we typically think of as modern, some of which actually have precedents dating back over 1000 years.

A Roman Washing Machine

Did the Romans have machines like this? Wikimedia Commons

Fulling was a major occupation in the Roman world that involved cleaning cloth by trampling it in tubs containing an alkaline solution, such as water and urine or the mineral known as fullers earth. But in ancient Antioch, in what is now Turkey, evidence suggests the process may have been mechanised, meaning the Romans may have effectively created the worlds first washing machine as far back as the 1st century AD.

Traditionally thought of as a medieval invention, the mechanical fulling mill would likely have consisted of a waterwheel that lifted a trip-hammer, which would then drop to press the cloth. A fullers’ canal mentioned in an inscription in Antioch would have supplied an estimated 300,000m3 of water at almost a metre per second, far in excess of what was needed for regular foot-powered fulleries. The power this could generate means it could have supported fulling on an industrial scale with maybe 42 pairs of mechanical hammers.

An Ancient Greek Computer

Antikythera mechanism. Wikimedia Commons, CC BY

In 1900, divers off the coast of the Greek island of Antikythera discovered something that changed our view of ancient science. The Antikythera mechanism is a bronze system of 30 gears that models the cycles of the sun and moon. It is effectively the first-known analogue computer, dating back to the 1st century BC. Set in a wooden box, the internal gears would have turned dials on the outside that showed the position of the sun and moon, as well as the rising and setting of specific stars and possibly the positions of Mars and Venus, too. Another dial could be moved to take into account leap years.

Although we now know that the Babylonians discovered how to use geometry to track the course of Jupiter in around 1800 BC, the Antikythera mechanism is the earliest known device that automatically calculates astronomical phenomena. We know of no other similiar devices for several hundred more years until the 8th century AD, when mathematician Muhammed al-Fazari is said to have built the first Islamic astrolabe. And nothing as mechanically sophisticated would appear again until the European astronomical clocks of the 14th century.

The Great Roman Bake-Off

Tomb of Eurysaces the Baker. Livioandronico2013/Wikimedia Commons, CC BY-SA

Bread was big business in the Roman world. It was given out by the state as part of a dole known as the annona. This meant that it was possible for people to make substantial amounts of money as bakers. One such person was Marcus Vergilius Eurysaces, a freedman (ex-slave) from Rome, who was so proud of his successful baking business that he commemorated it on his tomb. Today it is one of the most striking monuments from ancient Rome.

The top of the monument is decorated with a series of scenes that show a range of baking activities including the mixing and kneading of dough, the forming of loaves and the baked loaves being stacked in baskets. The most curious part, however, is the cylinders that make up the bulk of the monument. These features have baffled scholars for quite some time. One convincing theory argues that it is likely that these cylinders are related to baking and may well represent an early dough-mixing machine. The idea is that a rotating metal arm would have been attached to each cylinder in order to mix the dough.

The First State Space Project

Starmen. Wikimedia Commons

Ninth-century Baghdad in what is now Iraq saw the rise of a growing scientific community, particularly in astronomy, centred around a library known as the House of Wisdom. The problem for these new scholars was that their books were written many centuries earlier and came from a wide range of different cultures including Persian, Indian and Greek that did not always agree. The Caliph al Mamun decided the only solution was to build an astronomical observatory so the citys scholars could determine the truth.

Observatories werent new but a state-sponsored scientific institution was. Its hard to be sure exactly which instruments were used in the al-Shammasiyya observatory, but they probably included a sundial, astrolabes and a quadrant set on the wall to measure the precise position of objects in the sky. The quadrant may have been the first of its kind to be used in astronomical observations. The scientists used these instruments to reassess Ptolemys Mathematical Treatise from the 2nd century AD, and to make numerous astronomical observations, including the latitudes and longitudes of 24 fixed stars.

Zena Kamash, Lecturer in Roman Art and Archaeology, Royal Holloway

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The Race To Hypersonic Speed: Will Air Passengers Feel The Benefits?

When Concorde entered service 40 years ago, it more than doubled the speed of air travel at a stroke. Following Concordes retirement, airliners today fly once more at subsonic speeds, but engineers worldwide are looking to a future in which high-speed flight is an everyday occurrence. Except they want to go one better: not at supersonic, but hypersonic speeds.

Aerospace giant Airbus was last year awarded a patent that details how a future hypersonic aircraft, with delta wings reminiscent of Concorde, could travel at Mach 4.5 fast enough to carry passengers between Paris and Tokyo in just three hours.

But inevitably, technology that has reached the commercial realm will already have been investigated by the military. The US, Russia and China have all carried out test flights of hypersonic vehicles those which travel at around five times the speed of sound with varying degrees of success. Each also has plans for weapons systems that could be developed from them.

Because while these are often referred to as fighter jets, in truth the machines are more similar to missiles. Without pilots, they sit atop rockets which boost them to high supersonic speeds (Mach 4 and above), at which point they start up their own engines (if equipped) and accelerate to even faster cruise speeds – but not for long, as they usually run out of fuel quickly, and most of their flight time is spent in a glide, albeit an extremely fast one.

Current missiles have operated in this fashion for decades. Intercontinental ballistic missiles (ICBM) and some shorter-range versions use the same sort of flight path, with the missile formed of multiple rocket stages to provide enough power to arc high into the atmosphere, only flying faster and higher. The now retired US AIM-54 Phoenix air-to-air missile had a top speed of Mach 5. What makes the current generation of hypersonic aircraft designs different is their capability to manoeuvre, making them harder to intercept.

X-43 rocket plane dropped from a B-52, seconds before igniting its scramjet engines and reaching a world record-holding 10,000km/h (Mach 9.8). NASA

The Need For Speed

Why bother? There are two main reasons for the fresh interest shown by the military in hypersonic aircraft. The first is that a very fast, highly manoeuvrable weapon is not easy to counter: it can be difficult to detect and its speed means that there is little time for defences to react, much less to actually take any action to stop it. This makes it a threat to supposedly heavily defended targets and most discussion of the Chinese hypersonic craft, dubbed Wu-14, and the Russian equivalent, the Yu-71, mention penetrating US missile defence systems as a primary aim.

The second relates to a requirement that has become more urgent in recent years, namely to shorten response time and to attack mobile targets. While drones, satellites and the like can locate them easily enough, highly mobile enemy units anything from terrorist groups to Scud missile launchers will not hang around waiting for the inevitable airstrike to be called in. A very fast weapons platform with the ability to manoeuvre means that once found, a target will have little time and less opportunity to escape.

Material Shortfall

Of course, to create a workable hypersonic vehicle, engineers have to overcome, or at least cope with, the severe environment encountered by something moving that fast. The main problem (from which most if not all the others stem) is heat heat from air friction and from the shock waves generated by moving faster than the speed of sound.

The temperatures a hypersonic vehicle encounters are so high that conventional materials cant withstand them and maintain their strength. There are materials that can insulate a structure from the heat, but they tend not to be very strong in themselves, and so any breach of insulation can quickly lead to catastrophic failure as demonstrated by the tragic loss of the space shuttle Columbia in 2003, and also of some current test vehicles. Research into new heat-resistant materials and suitable manufacturing techniques is therefore a priority.

High air temperatures also reduce the thrust of an air-breathing jet engine, so new propulsion concepts are also needed relying on rocket engines tends to lead to overly large and heavy aircraft. Among the companies leading the way on propulsion technology is British company Reaction Engines, which is testing the revolutionary Sabre variable-cycle engine.

Travelling at very high speeds will also require advanced sensors and controls. New materials will be needed again, as conventional radomes and antennae would never withstand the heat. Conformal antennae where the crafts fuselage skin is used as the transmitter and receiver are a possibility, though this is not guaranteed to work. Depending on just how fast the vehicle is designed to travel, ionisation of the air around it could interfere with radio-frequency sensors and communications.

Hypersonic Flight For All?

Whether its possible to create a crewed or passenger hypersonic aircraft is still up for debate. But producing any sort of hypersonic vehicle is a long-term project that will take a lot of time and effort and a whole lot of money. Patents mark the ground as to where some may follow. But who out there has the will, the persistence and the funds to do so?

Phillip Atcliffe, Senior Lecturer in Aeronautical Engineering, University of Salford

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Freestyle Skiing With Bobby Brown Is One Crazy Ride

Freestyle Skiing With Bobby Brown Is One Crazy Ride

Extreme skier Bobby Brown shows off his best tricks in this latest video. With his buddy Erik Mehus recording on a GoPro, the two hit the slopes in Breckenridge, Colorado to pull off some sweet freestyle moves.

It’s no surprise Bobby is a famous Winter-X Games gold medalist. He’s also the first skier to ever to land a Switch Double Misty 1440, and one of the first to complete a Triple Cork 1440.


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Lifeguard Drone Saves Two Stranded Swimmers During Pilot Mission

A new type of drone was being tested by Australian lifeguards on Thursday when it was roped into the real-life rescue of two teenagers caught in rough, 9-foot (2.7-meter) swells off the coast New South Wales.

In a world first, the high-tech unmanned automated vehicle (UAV) delivered a large floatation device to the distressed swimmers, enabling them to paddle closer to the shore while actual human lifeguards raced to the scene. Video from the drone’s cameras captured this moment, below:

“I was able to launch it, fly it to the location, and drop the pod all in about one to two minutes,” said Jai Sheridan, a supervisor lifeguard who was piloting the drone, in a statement. “On a normal day that would have taken our lifeguards a few minutes longer to reach the members of the public.” 

In addition to the floatation device we saw deployed, the specialized UAV comes with a defibrillator, electromagnetic shark repellant device, and personal survival kit.

The idea to utilize drone technology for robo-lifeguarding stems from a partnership between an organization called Surf Life Saving New South Wales and the Australian government’s $16 million (AUD) shark deterrent program. For the past 18 months, this collaborative group has been using a different model of the UVA to monitor sharks along popular areas of coastline. These versions are equipped with camera-linked software that can recognize the shape of a shark in the water below and send an alert to operators.

Creating a drone platform with the technology and payload capability necessary to meet the project’s specifications took three years, according to manufacturer Westpac Little Ripper.

The trend of using unmanned craft for lifesaving operations has swept other nations as well. In the US, law enforcement and search and rescue agencies are rapidly incorporating aerial drones to expand their capabilities. 

A leader in this field is the Texas-based Center for Robot-Assisted Search and Rescue (CRASAR), a crisis response and research organization whose experts and devices have assisted during disasters for almost 20 years. Their deployments include the collapse of the World Trade Center (2001), Hurricane Katrina (2005), and the Japanese tsunami of 2011. The organization also develop next-generation technology

Meanwhile in the Mediterranean, a remote-controlled floating tube – cutely named EMILY (for Emergency Integrated Lifesaving Lanyard) – has been put to work helping refugees who have capsized while trying to cross the sea into Greece. 

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A Google Street View Car Accidentally Caught The Solar Eclipse – Check Out What It Saw

On August 21, 2017, while everyone else in North America was busy adjusting their cardboard viewing glasses and cursing at fog or clouds, a dedicated Google Street View driver just kept cruising through the town of Maryland Heights, Missouri; thus capturing for posterity what it looked like to experience the 2017 Great American Solar Eclipse from the path of totality.

The public tip-off to Google’s serendipitous astronomical photography came from eclipse-chaser Michael Kentrianakis, who told how to view the images at last week’s 2018 Northeast Astronomy Forum after being informed himself by online sources. 

“I guess those Google vans photographing every road on the planet don’t stop for nothing. Not even during the night of a total solar eclipse,” Kentrianakis wrote on Facebook.

“Drive on this Google Map right into the darkness of the eclipse or look up in the sky and see the Sun blocked by the Moon in what was a prolonged Diamond Ring just outside the limit of totality near St. Louis. Pretty darn neat.”

To take a look yourself – without risking permanent retinal burns from eschewing protective eyewear – simply cruise the route between 2000 and 2048 on McKelvey Hill Drive, area code 63043. Along the way, you toggle to the side to see transfixed locals or even pan upward to see the obscured Sun (though sadly, the glowing halo is too overexposed to make out clearly).

Officially declared by NASA to be the most viewed solar eclipse in history, last summer’s event was the first total eclipse to pass over the US since 1978, and the first to cross the entirety of the 48 contiguous states since 1918. Those fortunate enough to live within a narrow band that swept diagonally across the country were treated to the sight of the Moon perfectly positioned in front of the Sun for just under three minutes, though people in other regions could still enjoy a thrilling, yet slightly off-center blocking.

And before you start to worry too much about how the driver missed an experience of a lifetime, take a close look at the images taken as you advance up the road to the north toward higher address numbers. At 2046 McKelvey Hill Drive, the sky is still dark, with the eclipse in full swing, yet just one “click” forward to 2048 reveals a bright, normal-looking sunny day – promising evidence that whoever was behind the wheel pulled over for a few minutes.

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Astronomers Solve Mystery Of Strange Object At The Center Of The Milky Way

G2, a mysterious object near the supermassive blackhole at the center of the galaxy, hosts what was once a pair of stars that have been merged by the enormous gravitational influence of their near neighbor.

Strange things happen at the center of galaxies. Black holes millions of times the mass of the sun produce enormous gravitational forces and emit x-rays. Stars crowd so close together, they are in danger of bumping into each other. Ionized streams of gas light up like auroras.

Yet even in such an intense environment, G2 is something special. It has puzzled astronomers, who initially suspected it of being a gas cloud approaching Sgr A*, the black hole at the galaxy’s center. Debate raged as to how much of it would survive the encounter

However, UCLA’s Professor Andrea Ghez challenged the assumption on which these ideas are based. G2, she argues in The Astrophysical Journal Letters, is not a gas cloud of roughly three Earth masses, as others have speculated, but instead contains a central star, one she suspects of a very interesting history.

Ghez’s conclusions are based on observations of G2 as it reached its closest approach (periapse) to Sgr A* in the course of its orbit. This happened earlier this year when G2 reached a distance of 3000 times the event horizon from Sgr A*. “It was one of the most watched events in astronomy in my career,” says Ghez.

A gas cloud lacking a central object, “should be tidally disrupted during periapse passage,” Ghez and her co-author’s suggest. However, using the 10m Keck telescopes and laser guide star adaptive optics to adjust for the effects of the Earth’s atmosphere, the authors found G2’s brightness and size remained the same and its orbital characteristics were consistent with a condensed object.

They propose the center of G2 is a star. “This star has a luminosity of ~30L? and is surrounded by a large (~2.6 AU) optically thick dust shell,” they argue.

Stars 30 times the brightness of the sun are not unusual; Vega and Sirius are a little above and below that respectively. However, Ghez says although we cannot see it directly, the team believe G2’s star is distinctive for its expansive size, the product of two stars merging together. This prompts an expansion that lasts around a million years before returning to a more normal diameter. 

“This may be happening more than we thought. The stars at the center of the galaxy are massive and mostly binaries,” syas Ghez. “It’s possible that many of the stars we’ve been watching and not understanding may be the end product of mergers that are calm now.”

The combination of the dense packing of stars at the galactic center, and the influence of Sgr A*’s gravity could cause stars to collide and join on a regular basis in a way that almost never happens in the outer reaches of the galaxy. G2’s collision occurred recently enough for us to see the process in action.

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10 Future Law Enforcement Technologies

If you thought getting scanned and groped at the airport was the end, boy are you in for a surprise. Police around the world advancing are their arsenal of weapons with powerful technologies. Soon police may be flying overhead with unmanned drones, using powerful lights to temporarily blind suspects, and even use new cloaking technologies for covert operations.  brings us this sci-fi themed list of new police technologies. 


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