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When biomaterials do not biodegrade

may continuously cause problems

In extreme conditions, it is possible that the different mechanical properties of the artificial bone graft may cause a re-fracture or become a source for bacterium growth in infection

In order to get around this issue

researchers decided to study the calcium carbonate found in the exoskeleton of sea coral and convert it into coralline hydroxyapatite (CHA)

then refined the material to produce coralline hydroxyapatite/calcium carbonate (CHACC)

This CHACC composition contained 15 percent of CHA in a thin layer around the calcium carbonate and had a strong, porous structure that has made CHA commercially successful, but contained significantly improved biodegrading properties to support natural bone healing.

not to say that the material is ready to be used across the globe

There is a ways to go before the material can match the benefits of an autograft

and can be used by the several million people worldwide that undergo bone grafting procedures each year

the development of the CHACC material could provide an important step toward creating a biodegradable material that could help patients in the future

could help researchers provide earlier warnings

During their study

scientists underwent a 50-day expedition on the Japanese drilling vessel Chikyu

They then drilled three holes in the Japan Trench area in order to study the rupture zone of the 2011 earthquake

a fault in the ocean floor where two of Earth's major tectonic plates meet deep beneath the surface of the Pacific Ocean.

The conventional view among geologists

has been that deep beneath the seafloor, where rocks are strong, movements of the plates can generate a lot of elastic rebound

Closer to the surface of the seafloor, where rocks are softer and less compressed, this rebound effect was thought to taper off

In fact

the largest displacement of plates before the 2011 tsunami occurred in 1960 off the coast of Chile

That's when a powerful earthquake displaced seafloor plates by an average of 20 meters

The Tohoku earthquake, in contrast, displaced its own plates by 30 to 50 meters.

So what caused this unexpectedly violent slip

the fault itself is very thin--less than five meters thick in the area sampled.

makes it the thinnest plate boundary on Earth.

In addition, clay deposits that fill the narrow fault are made of extremely fine sediment, which makes it extremely slippery

these findings don't just show researchers a bit more about the past; they also have implications for the future

Other subduction zones in the northwest Pacific where this type of clay is present--from Russia's Kamchatka peninsula to the Aleutian Islands--may also be capable of generating similar, huge earthquakes

at a distance of 13 feet, 3 inches (4.04 meters) from the laser and telescope on rover's mast

Chemistry and Camera instrument (ChemCam) uses the infrared laser to excite material in a pinhead-size spot on the target into a glowing, ionized gas, called plasma.

ChemCam observes that spark with the telescope and analyzes the spectrum of light to identify elements in the target

As of the start of December, ChemCam has fired its laser on Mars more than 102,000 times, at more than 420 rock or soil targets

The instrument has also returned more than 1,600 images taken by its remote micro-imager camera

Each pulse delivers more than a million watts of power for about five one-billionths of a second

The technique used by ChemCam, called laser-induced breakdown spectroscopy, has been used to assess composition of targets in other extreme environments, such as inside nuclear reactors and on the sea floor

we're capable of doing extremely complicated things without knowing explicitly what we are doing

The researchers recruited 100 university students and members from the surrounding community to participate in an experiment

The participants completed a short typing test

Then, they were shown a blank QWERTY keyboard and given 80 seconds to write the letters in the correct location

On average, they typed 72 words per minute, moving their fingers to the correct keys six times per second with 94 percent accuracy

By contrast, they could accurately place an average of only 15 letters on a blank keyboard.

The fact that the typists did so poorly at identifying the position of specific keys didn't come as a surprise

For more than a century, scientists have recognized the existence of automatism: the ability to perform actions without conscious thought or intention

Automatic behaviors of this type are surprisingly common, ranging from tying shoelaces to making coffee to factory assembly-line work to riding a bicycle and driving a car

What did come as a surprise, however, was evidence that conflicts with the basic theory of automatic learning which holds that it starts out as a conscious process and gradually becomes unconscious with repetition

According to the widely held theory, when you perform a new task or the first time, you are conscious of each action and store the details in working memory

Then, as you repeat the task, it becomes increasingly automatic

This allows you to think about other things while you performing the task but your conscious recollection of the details gradually fades away

researchers were surprised when they found evidence that the typists never appear to memorize the key positions, not even when they are first learning to type.

Evidence for this conclusion came from another experiment included in the study

The researchers recruited 24 typists who were skilled on the QWERTY keyboard and had them learn to type on a Dvorak keyboard, which places keys in different locations.

After the participants developed a reasonable proficiency with the alternative keyboard, they were asked to identify the placement of the keys on a blank Dvorak keyboard

On average, they could locate only 17 letters correctly, comparable to participants' performance with the QWERTY keyboard.

According to the researchers, the lack of explicit knowledge of the keyboard may be due to the fact that computers and keyboards have become so ubiquitous that students learn how to use them in an informal, trial-and-error fashion when they are very young

The water gets contaminated with dangerous chemicals in the process, requiring costly treatment before factories can dump it back into waterways—or wreaking havoc when factory owners dodge cleanup rules

Scientists are just starting to study this idea, however, it remains to be seen if it's commercially viable

In this experiment, the Indian team tested seven azo dyes, which are cheap and popular in the industry

The scientists found different dyes moved through silkworms' bodies differently. Some never made it into the worms' silk at all

Others colored the worms and their cocoons, but the color molecules settled mostly in the sticky protein the worms add to their cocoons

That sticky stuff gets washed away before the silk is turned into fabric

Only one dye, named "direct acid fast red," showed up in the final, washed silk threads. By the time it made it there, it was a pleasant, light pink.

HD 106906 b

throws a wrench in planet formation theories

no model of either planet or star formation fully explains what we see

It is thought that planets close to their stars, like Earth, coalesce from small asteroid-like bodies born in the primordial disk of dust and gas that surrounds a forming star

this process acts too slowly to grow giant planets far from their star

Another proposed mechanism is that giant planets can form from a fast, direct collapse of disk material

primordial disks rarely contain enough mass in their outer reaches to allow a planet like HD 106906 b to form

Several alternative hypotheses have been put forward, including formation like a mini binary star system

binary star system can be formed when two adjacent clumps of gas collapse more or less independently to form stars, and these stars are close enough to each other to exert a mutual gravitation attraction and bind them together in an orb

It is possible that in the case of the HD 106906 system the star and planet collapsed independently from clumps of gas, but for some reason the planet's progenitor clump was starved for material and never grew large enough to ignite and become a star

one problem with this scenario is that the mass ratio of the two stars in a binary system is typically no more than 10-to-1.

the mass ratio is more than 100-to-1,

extreme mass ratio is not predicted from binary star formation theories – just like planet formation theory predicts that we cannot form planets so far from the host star

is also of

interest because researchers can still detect the remnant "debris disk" of material left over from planet and star formation.

potential to help us disentangle the various formation models

Future observations of the planet's orbital motion and the primary star's debris disk may help answer that question

At only 13 million years old, this young planet still glows from the residual heat of its formation

Because at 2,700 Fahrenheit (about 1,500 degrees Celsius) the planet is much cooler than its host star

it emits most of its energy as infrared rather than visible light

Earth

formed 4.5 billion years ago

about 350 times older than HD 106906 b.

Direct imaging observations require exquisitely sharp images, akin to those delivered by the Hubble Space Telescope

To reach this resolution from the ground requires a technology called Adaptive Optics, or AO

The team used the new Magellan Adaptive Optics (MagAO) system and Clio2 thermal infrared camera

mounted on the 6.5 meter-diameter Magellan telescope in the Atacama Desert in Chile to take the discovery image

MagAO was able to utilize its special Adaptive Secondary Mirror

585 actuators, each moving 1,000 times a second, to remove the blurring of the atmosphere

optimized for thermal infrared wavelengths, where giant planets are brightest compared to their host stars

planets are most easily imaged at these wavelengths

The team was able to confirm that the planet is moving together with its host star by examining Hubble Space Telescope data taken eight years prior for another research program

This planet discovery is particularly exciting because it is in orbit so far from its parent star. This leads to many

questions about its formation history and composition

Chang’e 3 is due to make a powered descent to the Moon’s surface on Dec. 14, firing the landing thrusters at an altitude of 15 km (9 mi) for a soft landing in a preselected area called the Bay of Rainbows or Sinus Iridum region.

The Bay of Rainbows is a lava filled crater located in the upper left portion of the moon as seen from Earth.

The ancient fresh water lake at the Yellowknife Bay area inside the Gale Crater landing site explored earlier this year

existed for periods spanning perhaps millions to tens of millions of years in length

before eventually evaporating completely after Mars lost its thick atmosphere.

the lake may have existed until as recently as 3.7 Billion years ago, much later than researchers expected

which means that life had a longer and better chance

before it was transformed into its current cold, arid state.

Researchers also announced that they are shifting the missions focus from searching for habitable environments to searching for organic molecules – the building blocks of all life as we know it.

the team believes they have found a way to increase the chance of finding organics preserved in the sedimentary rock layers

a mission that is now dedicated to the search for that subset of habitable environments which also preserves organic carbon

the ancient lake at Yellowknife Bay was likely about 30 miles long and 3 miles wide.

The shallow ancient lake may have been about 30 miles long by 3 miles wide (50 by 5 kilometers

the research team estimates that the lake existed for at least tens of thousands of years — and perhaps much longer, albeit on a possibly on-and-off basis

for times when the lake might have been dry, the groundwater's still there

The lack of weathering on Gale Crater's rim suggests that the area was cold when the lake existed

raising the possibility that a layer of ice covered the lake on a permanent or occasional basis

These are entirely viable habitable environments for chemolithoautotrophs

Curiosity was not designed to hunt for signs of life on Mars