Archive for June, 2012

NASA finds hidden ocean on Saturn’s moon Titan

Posted in THE UNIVERSE & SPACE SCIENCE on June 30, 2012 by 2eyeswatching

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NASA finds hidden ocean on Saturn’s moon Titan

 Robert T. Gonzalez


NASA finds hidden ocean on Saturn's moon Titan

Using incredibly precise measurements from NASA’s Cassini spacecraft, researchers have concluded that Saturn’s biggest moon is likely hiding a global, sub-surface water ocean, 100 km beneath its surface.

One of the most enigmatic bodies in our solar system just got even more intriguing.

Cassini has flown by Titan more than 80 times since entering Saturn’s orbit in 2004, and its observations have confirmed that, as moons go, Titan is a weird one. It’s bigger than the planet Mercury. It’s the only moon with a real atmosphere (an atmosphere denser than Earth’s, in fact). It experiences Earthlike weather, such as rain and snow. It’s home to familiar geological features like valleys, plains and deserts — and it’s the only known object besides Earth with standing bodies of liquid.

And yet these observations, while numerous, have all been skin deep. “In contrast,” writes planetary scientist Luciano Iess, in today’s issue of Science, “information on the moon’s deep interior is scarce.”

One does not simply drill into Titan, and there are no geologists on the moon’s surface to measure its seismic waves. The absence of a detectable internally generated magnetic field means that everything we know about the interior of Titan has come from careful analysis of its orbit, rotation, gravity and topography. Fortunately for clever scientists everywhere, careful analysis can reveal incredible things.

To detect the tides of Titan, Iess and his colleagues had to get creative. Titan travels around Saturn in an elliptical orbit, experiencing the most gravitational pull as it approaches its closest point in orbit (pericenter), and the least at its farthest (epicenter). These variations give rise to tides, which squeeze at the moon’s surface and cause it to flex. Tidal flexing leads to distortions in Titan’s gravitational field that affect the speed at which Cassini approaches and recedes from the moon during flybys. It’s this last bit — the effect of Titan’s changing gravitational field on Cassini’s velocity — that is ultimately measured by the spacecraft’s onboard equipment.

The less dense the moon’s interior, the more its surface flexes throughout its orbit, and the greater the distortions in the moon’s gravitational field. Since Titan takes just 16 days to make a full trip around Saturn, Iess and his colleagues were able to use Cassini’s velocity over the course of six different flybys to estimate the changes in Titan’s shape throughout its orbit. The researchers calculated that if Titan were composed entirely of rock, the moon would experience bulges in its surface of up to one meter in high. Cassini’s velocity measurements indicate the moon actually experiences bulges that are ten times that height.

NASA finds hidden ocean on Saturn's moon TitanWhen combined with data from previous research, including investigations into Titan’s mysterious orbit, the researchers claim the most likely model of Titan’s interior is one like the one pictured here, which depicts a global ocean located beneath an icy shell tens of kilometers thick. “Cassini’s detection of large tides on Titan leads to the almost inescapable conclusion that there is a hidden ocean at depth,” said Iess.

The fact that the ocean’s waters are located beneath a sheet of ice does not bode well for life; most experts contend that life is most likely to spring from places where water comes into contact with rock. Having said that, the models used by Iess and his colleagues have no way of telling whether the floor of Titan’s subsurface ocean is made up of rock or ice, so Titan aliens are not entirely out of the question.

For now, however, most planetary scientists are interested in the ocean’s role in maintaining the moon’s diminishing atmosphere.

“The presence of a liquid water layer in Titan is important because we want to understand how methane is stored in Titan’s interior and how it may outgas to the surface,” said Cassini team member Jonathan Lunine.

“This is important because everything that is unique about Titan derives from the presence of abundant methane, yet the methane in the atmosphere is unstable, and will be destroyed on geologically short timescales.”

The researchers’ findings are published in the latest issue of Science

Incredible medical breakthrough allows doctors to inject oxygen into the bloodstreams of people who can’t breathe


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Incredible medical breakthrough allows doctors to inject oxygen into the bloodstreams of people who can’t breathe

George Dvorsky

In a monumental breakthrough with far ranging implications, cardiologists at the Children’s Hospital Boston in Massachusetts have kept suffocating rabbits alive for 15 minutes with injections of oxygen-filled microparticles. The groundbreaking procedure could conceivably prevent millions of deaths each year caused by such things as heart attacks and choking.

Developed by John Kheir and his team at CHB, the technique could prevent heart attacks and any kind of injury caused by oxygen deprivation once it’s proven safe for human use. It might also be used to avoid cerebral palsy which is caused by a compromised fetal blood supply. Assuming the procedure could ever be developed for use outside of clinical settings, people could use it in the event of emergencies. It could also become part of a first aid kit in anticipation of problems -– a welcome breakthrough for scuba divers and high altitude climbers.

The researchers also note that the technique could be used to augment oxygen delivery to at-risk organs, while opening the door to entirely new diagnostic techniques.

Outside of medical use, the procedure could also impact on normal human functioning. Swimmers and divers could conceivably take the injections and stay underwater for unprecedented lengths of time.

Writing in the journal Nature, Duncan Graham-Rowe explains how it was done:


The microcapsules used by Kheir and his team…consist of single-layer spherical shells of biological molecules called lipids, each surrounding a small bubble of oxygen gas. The gaseous oxygen is thus encapsulated and suspended in a liquid emulsion, so can’t form larger bubbles.

The particles are injected directly into the bloodstream, where they mingle with circulating red blood cells. The oxygen diffuses into the cells within seconds of contact, says Kheir. “By the time the microparticles get to the lungs, the vast majority of the oxygen has been transferred to the red blood cells,” he says. This distinguishes these microcapsules from the various forms of artificial blood currently in use, which can carry oxygen around the body, but must still receive it from the lungs.

In the experiment, the rabbits underwent 15 minutes of complete tracheal occlusion (their air passageways were blocked), but showed no ill effects during the procedure.

Looking ahead, Kheir noted that a primary advantage of his technique is how fast it goes to work. Graham-Rowe writes:

He thinks that it might be possible to modify the technique to keep subjects alive for as much as 30 minutes, but doubts that it could be pushed much further. Because the microparticles do not recirculate, it would be necessary to continuously infuse fresh ones into the blood, and there are limits to how much extra fluid can be pumped into the bloodstream. “It’s not going to replace the lungs, it just replaces their function for a limited period of time,” says Kheir.

You can read the entire study at Science Translational Medicine.

Image via Inset image via Nature.

How to Kill a Parasitic Worm Living Inside of You


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How to Kill a Parasitic Worm Living Inside of You

 Keith Veronese

How to Kill a Parasitic Worm Living Inside of You

Parasitic worms are the stuff of nightmares — worms as big as twelve feet long can rummage through your intestines, and then leave in the middle of the night. Urban legends tell tales of tapeworms carried by diet pills. Some of the weird schemes for removing these parasites include a combination of duct tape, candy bars, and bodily orifices.

What is the reality behind these parasites? And how can you really get rid of one, without the need for extreme measures?

Top image: Tapeworm art by Damnations_Shadow/Flickr.

Tapeworms hide in your food
Obtaining a beef or pork parasite is rather easy, but also easily avoidable. Undercookedmeat is a common way to ingest both Taenia solium and Taenia saginata, whose larvae often live inside pigs and cows. Either species of tapeworm can grow up to twelve feet and live inside of a human host for several years.

Tapeworms can cause a variety of health problems, including seizures, obscured or blurry vision, and a swelling of the brain if larvae move to that region. Most infections are asymptomatic, however, with the patient only realizing they are harboring a tapeworm when they pass a wiggling section of the worm while defecating. Manual removal of a tapeworm through the mouth is also possible, but not fun.

Hookworms lay traps in the soil
The hookworm is much smaller than a tapeworm. These parasites are rarely more than a centimeter long, and burrow into your small intestine to feast on your blood. Since hookworms latch onto your small intestine and divert nutrients away from the bloodstream, they’re actually more problematic than tapeworms. Hookworm infection can lead to anemia, slower cognitive growth, and malnutrition.

Hookworms infect over a billion people worldwide. The vast majority of these people live without advanced sanitation, amidst subtropic and tropical climates. Transmission of hookworms is quite devious and more involved than tapeworm transmission. When the soil cools off at night, hookworm larvae extend out of the soil, waiting to latch onto any human foot that passes overhead. Local sanitation problems come into the equation when larvae are passed through feces, allowing them to infect humans through both direct contact and contaminated water.

Pinworms sneak out of your anus at night
Tiny pinworms lay eggs around a host’sanus, leading to an itching sensation, which creates a vicious cycle if your fingers come in contact with your mouth — since this allows the eggs to enter the digestive tract.

Pinworms are found worldwide, and they’re the bane of many North American elementary schools, as infections often begin through human contact or through recently used surfaces like toilet seats, faucets, and doorknobs. Thankfully, the symptoms of a pinworm infection are not nearly as severe as a hookworm invasion, — the worst pinworm symptoms include itchiness, irritability, and weight loss.

A common test for pinworms involves taping the anal region of a possible host, and inspecting the tape for eggs after a good night’s sleep. (If you can sleep in that condition.) Pinworms don’t just travel to the anus and lay eggs as part of a cruel joke — they need access to fresh air for their eggs to mature.

Killing the unwelcome guests within
A number of pharmaceutical treatments are available to rid humans of unwelcome worm guests. These drugs are called anthelmintics — and this includes several different types of drug, each with different methods of killing worms. (Prior to the development of small-molecule pharmaceuticals, people used to eat tobacco, pineapple, and honey to rid the body of worms.)

Benzimidazoles are the largest and most versatile class of anthelmintics. This class of drugs starves the worms by cutting off their ability to absorb glucose. Benzimidazoles bind to the protein beta-tubulin, which disrupts any processes that make use of microtubules.

Albendazole is the MVP of this class of drug — it works against pinworms, hookworms, tapeworms, and a variety of other worm infections. The broad spectrum application and low cost of albendazole makes it a first-line defense against parasitic worms.

Ivermectin is an increasingly important drug used for treating parasitic infections. Ivermectin interferes with a parasite’s neurotransmitters, paralyzing the invaders indiscriminately, and eventually leading to death.

Unfortunately, Ivermectin does not work against tapeworms, but the drug’s method of action allows it to eliminate most intestinal worms, as well as external parasites like scabies and lice. Patients can also wait three months to a year between doses of ivermectin. The infrequent dosage and wide scale application of ivermectin make it the anthelmintic of choice for treatment of parasites in Third World countries.

Albendazole and ivermectin are only two of a legion of available anthelmintics. But just like antibiotic-resistant infections, we’re starting to see parasites that have resistance to anthelmintics. That’s why there’s a wide variety of other drugs to fight parasitic worms. But any strategy for fighting parasites has to include more personal hygiene and sanitation, as well as dosing family members with anti-parasite drugs — as these worms tend to pass from family member to family member.

Tapeworm, pinworm, and hookworm images are from the CDC Public Health Image Library. Sources linked within the article.


What If Humans Had Eagle Vision?


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What If Humans Had Eagle Vision?

By: Natalie Wolchover, Life’s Little Mysteries Staff Writer
CREDIT: Karl Tate (infographic); 5607594264 | Shutterstock (man)

If you swapped your eyes for an eagle’s, you could see an ant crawling on the ground from the roof of a 10-story building. You could make out the expressions on basketball players’ faces from the worst seats in the arena. Objects directly in your line of sight would appear magnified, and everything would be brilliantly colored, rendered in an inconceivable array of shades.

The more scientists learn about eagle vision, the more awesome it sounds. Thanks to developing technologies, some aspects of their eyesight may eventually be achievable for humans. Others, we can only imagine.

Eagles and other birds of prey can see four to five times farther than the average human can, meaning they have 20/5 or 20/4 vision under ideal viewing conditions. Scientists have to cook up special experiments to judge eagles’ eyesight — your optometrist’s alphabet eye charts are of no use, after all —  and one common setup involves training the birds to fly down a long tunnel toward two TV screens. One screen displays a striped pattern, and the birds get a treat when they land on it. Scientists test their acuity by varying the width of the stripes and determining from what distance the eagles begin to veer in the correct direction.

According to William Hodos, a distinguished professor emeritus at the University of Maryland who has studied the visual acuity of birds since the 1970s, two eyeball features confer eagles’ sharper vision. First, their retinas are more densely coated with light-detecting cells called cones than human retinas, enhancing their power to resolve fine details just as higher pixel density increases the resolving power of cameras.

Second, they have a much deeper fovea, a cone-rich structure in the backs of the eyes of both humans and eagles that detects light from the center of our visual field. “Our fovea is a little shell or bowl, while in hawk or eagle it’s a convex pit. Some investigators think this deep fovea allows their eyes to act like a telephoto lens, giving them extra magnification in the center of their field of view,” Hodos told Life’s Little Mysteries.

On top of sharp focus and a central magnifier, eagles, like all birds, also have superior color vision. They see colors as more vivid than we do, can discriminate between more shades, and can also see ultraviolet light — an ability that evolved to help them detect the UV-reflecting urine trails of small prey. But there’s no way to know what these extra colors, including ultraviolet, look like. “Suppose you wanted to describe the color of a tomato to someone who was born blind. You couldn’t do it. We can’t even guess what they’re subjective sensation of ultraviolet light is,” Hodos said. [Red-Green & Blue-Yellow: The Stunning Colors You Can’t See]

Life with 20/5 vision

Eagle vision wouldn’t change how we perform most daily activities  — such as reading computer screens or the newspaper, or finding milk in a crowded refrigerator — but how we perceive the world and use our eyes would certainly be different. It’s perhaps easiest to consider our new powers in the context of how eagles use them: for hunting.

On top of the ability to see farther and perceive more colors, we would also have nearly double the field of view. With our eyes angled 30 degrees away from the midline of our faces like an eagle’s, we would see almost all the way behind our heads with a 340-degree visual field (compared to normal humans’ 180 degree field); this would confer a clear advantage in hunting and self-defense.

With eagle eyes, we would swivel our heads constantly. To locate prey or any other object of interest in the distance, you’d periodically turn your head to the side to sweep your fovea (telephoto lens) across your field of view. After spotting what you’re looking for in this manner, you’d redirect your head toward it and use stereoscopic vision — combining the viewpoints of both eyes to gauge distance — to calibrate the speed of your approach.

Enhanced perception and hunting prowess would likely come with a few drawbacks. “I would say that birds probably have a greater proportion of their brain volume devoted to visual processing than other groups of animals. Now the question of what it comes at the expense of: most birds appear not to have a well-developed sense of smell or taste,” Hodos said.

It’s more difficult to say how your more sophisticated cognitive processes would fare. “Birds have areas that seem to function like the cortex [the part of our brains responsible for memory, language and complex thought], but it’s arguable. But in terms of their ability to solve problems and so on, they match what many mammals can do. Many birds have superb memory,” he said. [The 5 Smartest Non-Primates on the Planet]

Maximizing our potential

Eagles’ high-flying lifestyle requires better vision than humans need, and the physical properties of our eyeballs limit us to 20/10 or 20/8 vision at best. Natural vision that good is extremely rare, but research by David Williams, director of the Center for Visual Science at the University of Rochester, and his colleagues may soon enable laser eye surgeons to achieve 20/10-or-better vision for a large percentage of patients, placing their visual acuity halfway between that of humans and eagles.

Williams and his colleagues use an instrument called a wavefront sensor to detect distortions in human vision. They shoot light into the eye and observe how it bounces back through hundreds of tiny lenses in the sensor. The aberrations in patterns created by those lenses serve as a map of the eye’s mistakes. Customized surgical techniques are being developed to implement the results of patients’ wavefront measurements, in order to correct their vision beyond 20/20.

Does China’s Cat-Eyed Boy Really Have Night Vision?


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Does China’s Cat-Eyed Boy Really Have Night Vision?

By: Natalie Wolchover, Life’s Little Mysteries Staff Writer
Nong You-hui’s teachers and parents claim he can see in the dark.
CREDIT: YouTube | ADG (UK)

According to a news reel from China, a young boy there possesses the ability to see in the dark. Like a Siamese cat’s, his sky-blue eyes flash neon green when illuminated by a flashlight, and his night vision is good enough to enable him to fill out questionnaires while sitting in a pitch black room — or so say the reporters who visited Nong Yousui in his hometown of Dahua three years ago.

The footage of Nong and his strange-looking eyes originally surfaced in 2009; it got little attention at the time, but is now making a splash all over the Web. If the boy really does have a genetic mutation that confers night vision, then he would be an interesting subject for analysis by vision scientists, evolutionary biologists, and genetic engineers alike — but does he?





The experts we shared the video with say Nong does have unusually colored irises considering his ethnicity, but he’s not the next step in human evolution. [6 Paranormal Videos Debunked ]

Night vision is made possible by a layer of cells, called the tapetum lucidum, in the eyes of cats and other nocturnal animals. This thin layer is a “retroreflector” — when a beam of light hits it, it reflects the light directly back along its incoming path. The reflected beam constructively interferes with the incoming light beam, amplifying the overall signal that hits the retina and enabling the animal to see in very low-light conditions. Retroreflection also causes cat eyes to flash when they are lit upon at night, and experts say Nong’s eyes, if they are truly catlike, should do the same. [Red-Green & Blue-Yellow: The Stunning Colors You Can’t See]

“It would be easy to test the boy’s eyes for retroreflection (eyeshine), which would be indicative of a tapetum lucidum,” said Nathaniel Greene, a physicist at Bloomsburg University of Pennsylvania who has studied retroreflection.

In fact, such a test is run in the video.

In the footage, Nong’s teacher claims the boy’s eyes flash when shined with a flashlight in the dark, but the reporters don’t seem to be able to catch the effect on camera. When Nong’s eyes are illuminated in the dark, they appear normal. James Reynolds, a pediatric ophthalmologist at State University of New York in Buffalo, noted, “A video could capture [eyeshine] easily, just like in nature films of leopards at night.”

Furthermore, there is no single genetic mutation that could produce a fully formed and functioning tapetum lucidum, Reynolds explained; such an ability would require multiple mutations, which wouldn’t occur all at once. Evolution happens incrementally, he said, not by leaps and bounds. “Evolutionarily, mutations can result in differences that allow for new environmental niche exploitation. But such mutations are modified over long periods. A functional tapetum in a human would be just as absurd as a human born with wings. It can’t happen,” he told Life’s Little Mysteries.

On the other hand, in the footage, the reporters gave Nong a questionnaire to fill out while sitting in a dark room, and they acted surprised by his ability to see and complete the fill-in-the-blank form. Even if he doesn’t have cat eyes, he may nevertheless have unusually good night vision, Reynolds said. He could have a rod-rich retina, for example — a retina that contains a higher than usual number of cells involved in light detection. Or the video could be a total hoax.

“It is hard to say what the truth is about this boy,” said Dennis Brooks, professor of ophthalmology at the University of Florida’s College of Veterinary Medicine. “A good ophthalmic examination by a physician ophthalmologist is in order, I think.”

Editor’s Note: Adam Hickenbotham, an optometrist and clinical researcher at University of California, Berkeley, contacted us to say he believes Nong has a mild case of ocular albinism. This would explain the boy’s lightly-pigmented irises, and would also cause him to have a lower than usual amount of pigment in his retinas. this would make them appear slightly reflective, and would cause Nong to have difficulty seeing in bright light.


Glory! Double Rainbow Seen from Space

Posted in THE UNIVERSE & SPACE SCIENCE on June 30, 2012 by 2eyeswatching

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Glory! Double Rainbow Seen from Space

OurAmazingPlanet Staff – Jun 27, 2012 02:31 PM ET

NASA’s Aqua satellite caught an arresting image of a rainbow-like optical phenomenon called a glory over the Pacific Ocean on June 20.

Glories can be seen on Earth with the naked eye when looking down upon fog or water vapor, as when climbing a mountain or looking down upon clouds from an airplane.

The phenomenon is caused by light scattered backward toward the viewer by individual water droplets, producing an oscillating pattern of colors ranging from blue to green to red to purple and back to blue again.

From the ground or an airplane, glories appear as circular rings of color. In the

satellite image, the lines of color appear straight against a backdrop of stratocumulus clouds. That’s because the satellite takes pictures perpendicular to its path, producing images of horizontal cross sections of the glory rings.

A wider view of the glory over the Pacific, west of Mexico’s Baja peninsula, taken by NASA’s Aqua satellite on June 20, 2012.
CREDIT: Jeff Schmaltz, LANCE MODIS Rapid Response 

Although glories look similar to rainbows, the way light is scattered to produce them is slightly different; Rainbows are formed by refraction and reflection, whereas glories are formed by backward diffraction. When light is refracted, it is bent by passing through mediums of different densities, such as water or a prism. Reflected light bounces off a surface at an angle equal to the angle it hit the surface at. Diffraction, though, involves light waves being scattered into a ring-like pattern.

Glories always appear around the spot directly opposite the sun, from the viewer’s perspective, a spot called the anti-solar point.

In the right of this image is another atmospheric spectacle: a row of so-called von karman vortices, caused by the Pacific island of Guadalupe disrupting the southern flow of clouds, like the wake of a ship.

Space Station Experiment Simulates Earth’s Magma

Posted in THE UNIVERSE & SPACE SCIENCE on June 28, 2012 by 2eyeswatching

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Space Station Experiment Simulates Earth’s Magma

by Nola Taylor Redd, Contributor
Date: 27 June 2012 Time: 07:01 AM ET
Liquid between two revolving spheres on the ISS moves much the same way Earth’s magma does, influenced by temperature and pressure changes.

Outer space seems an unlikely place to study movement beneath the Earth’s surface, but an experiment that was performed on the International Space Station is helping scientists do just that.

Geoflow II, a simulation of magma movement in Earth’s mantle, is helping scientists study how heat and pressure influence the behavior of molten rock, in an experiment that couldn’t have been duplicated on Earth.

“The biggest problem on Earth is the gravitational acceleration. On the ISS, we have micro-gravity conditions,” Florian Zaussinger, of Brandenburg University of Technology at Cottbus in Germany, explained.

The readings produced by a series of simulations in the Fluid Science Laboratory aboard the ISS are being studied by scientists on Earth.  [Graphic: The International Space Station Inside and Out]

“The Earth’s mantle is a very complex fluid,” Zaussinger told by email. “We know more about the sun’s interior than about our own mantle.”

Geoflow II Experiment
Two concentric spheres rotate around each other, with a fluid between them to represent Earth’s mantle.

A tiny planet in space

The Geoflow II payload included two concentric spheres that rotated, one inside the other, with silicone oil between them to simulate the mantle. The inner sphere, which represented the Earth‘s core, was warmer than the “crust” sphere. As the two rotated, scientists on Earth monitored the motion of the oil caused by variations in temperature and pressure.

At the same time, a high-voltage electric field created a controlled artificial gravity for the spheres, directing it toward the common center of the spheres, as gravity on a planet would function.

The space station doesn’t mimic the zero-gravity conditions of space, but it comes close. Zaussinger described the conditions as “unique and not possible in this way on Earth.”

The mantle starts at 22 miles (35 kilometers) beneath the surface and can descend as deep as 1,800 miles (3,000 km). Drills have descended barely 8 miles (12 km), so scientists rely on models and calculations to understand how the mantle behaves.

Creating an analog of the layers of the Earth gives them something for comparing simulations.

GeoFlow II — the sequel to a study of convection within the Earth’s core — simulated the molten rock beneath the crust, allowing European Space Agency astronaut André Kuipers to observe plumes of hot liquid rising toward the outer shell. Simulations predicted similar upwellings when extreme forces press on the mantle, and could explain the line of volcanoes that created the Hawaiian island chain. Movement of Earth’s middle layer also could contribute to earthquakes.

Scientists from six universities in France, Germany, and the United Kingdom are analyzing the results. Understanding how the hot rocky mantle oozes could improve the overall understanding of fluid flows for industrial applications such as spherical gyroscopes, bearings, and centrifugal pumps.

Although the data is fresh, it is already providing some insights. “We found significant differences to existing models,” Zaussinger said.

In 2008, the original GeoFlow studied flows in the Earth’s core and composition. After returning to Earth, it was modified to study the patterns in the mantle, then launched in February of 2011.

A third mission is slated to run this fall.