Thursday, March 31, 2016
The Egg Nebula
This colorful image shows a cosmic lighthouse known as the Egg Nebula, which lies around 3000 light-years from Earth. The image, taken with the NASA/ESA Hubble Space Telescope, has captured a brief but dramatic phase in the life of a Sun-like star.
The Egg Nebula is a ‘preplanetary nebula’. These objects occur as a dying star’s hot remains briefly illuminates material it has expelled, lighting up the gas and dust that surrounds it.
These objects will one day develop into planetary nebulas which, despite the name, have nothing at all to do with planets. They gained their rather misleading title because when they were discovered in the 18th century they resembled planets in our Solar System when viewed through a telescope.
Although the dying star is hidden behind the thick dust lane that streaks down the centre of this image, it is revealed by the four lighthouse-like beams clearly visible through the veil of dust that lies beyond the central lane.
The light beams were able to penetrate the central dust lane due to paths carved out of the thick cloud by powerful jets of material expelled from the star, although the cause of these jets is not yet known.
The concentric rings seen in the less dense cloud surrounding the star are due to the star ejecting material at regular intervals – typically every hundred years – during a phase of the star’s evolution just prior to this preplanetary nebula phase. These dusty shells are not usually visible in these nebulas, but when they are it provides astronomers with a rare opportunity to study their formation and evolution.
The fleeting nature of this phase in a star’s life – which occupies only a few thousand of the star’s few billion years of existence – and the fact that they are fairly faint make it rare to capture them in action. In fact, the Egg Nebula, the first of its kind to be identified, was discovered only 40 years ago.
This image was taken with Hubble’s Advanced Camera for Surveys. Artificial colours are used to represent how the light from the star reflects off the dust – this can tell scientists about the physical properties of the dust.
The image combines observations with three different polarising filters, each showing light vibrating at a specific orientation. The three filters have been coloured red, blue and green, and all three observations were made at a wavelength of 0.606 microns. The image spans 1.2 light-years. North is to the right and east is up.
Image & Info via ESAhttp://www.esa.int/spaceinimages/Images/2014/11/The_Egg_Nebula
Credit: NASA/ESA/Hubble Heritage Team (STScI/AURA). Acknowledgment: W. Sparks (STScI) & R. Sahai (JPL)
Wednesday, March 30, 2016
Scientists have grown 'dinosaur legs' on a chicken for the first time
Until very recently, one of the biggest myths in science was that all dinosaurs have been extinct for the past 65 million years. But thanks to new fossil discoveries that filled in our knowledge about avian dinosaurs, we now know that only some dinosaurs went extinct following an asteroid collision with Earth - others survived and gave rise to the birds we live with today.
To figure out how this evolution occurred, researchers in Chile have manipulated the genes of regular chickens so they develop tubular, dinosaur-like fibulas on their lower legs - one of the two long, spine-like bones you’ll find in a drumstick.
In avian dinosaurs such as the Archaeopteryx, the fibula was a tube-shaped bone that reached all the way down to the ankle. Another bone, the tibia, grew to a similar length alongside it.
As evolution progressed through to a group of avian dinosaurs known as the Pygostylians, the fibula became shorter than the tibia, and sharper and more splinter-like towards the end, and it no longer reached the ankle.
While modern bird embryos still show signs of developing long, dinosaur-like fibulae, as they grow, these bones become shorter, thinner, and also take on the splinter-like ends of the Pygostylian bones, and never make it far enough down to the leg to connect with the ankle.
Source:http://www.sciencealert.com/scientists-have-grown-dinosaur-legs-on-a-chicken-for-the-first-time
Watch:https://www.youtube.com/watch?v=0QVXdEOiCw8
New state of matter?
New state of matter? : Kind of a tall claim, but that's what researchers at Japan's Tohoku University are stating. They have created what's called a Jahn-Teller metal by inserting Rubidium into Buckyballs. What they have apparently done is by combining the two, the resultant complex crystalline structure seems to conduct, insulate, and magnetize while acting like a metal. Will have to see more papers before one is fully convinced of this...
Game changer for materials science : Superconducting lattices of fullerides – C60 plus three alkali-metal atoms – have been studied for more than two decades, and provide an interesting test bed. This is because the distance between fulleride molecules – and hence the electronic properties of the material – can be adjusted by applying pressure to the material or doping it with different kinds of atoms.
Strange behavior : The surprising thing about this metal–insulator transition is that it involves an intermediate state never seen before. The researchers have dubbed this a "Jahn–Teller metal" because when the material is studied using infrared spectroscopy, the fulleride molecules clearly show rugby-ball distortions, which were only known to occur in insulators. However, nuclear magnetic resonance measurements clearly show that electrons are able to "hop" from one molecule to the next – which is the signature of a conducting metal. "An interesting question is how the material can have both Jahn–Teller distortions and be a metal?" says Matthew Rosseinsky of the University of Liverpool, UK, who was involved in the research.
References and links
Paper link: http://advances.sciencemag.org/content/1/3/e1500059
http://physicsworld.com/cws/article/news/2015/may/06/new-state-of-matter-found-in-crystal-made-from-buckyballs
http://www.popularmechanics.com/science/energy/a15501/jahn-teller-metal-new-state-matter/
http://nanotechweb.org/cws/article/tech/61131
Game changer for materials science : Superconducting lattices of fullerides – C60 plus three alkali-metal atoms – have been studied for more than two decades, and provide an interesting test bed. This is because the distance between fulleride molecules – and hence the electronic properties of the material – can be adjusted by applying pressure to the material or doping it with different kinds of atoms.
Strange behavior : The surprising thing about this metal–insulator transition is that it involves an intermediate state never seen before. The researchers have dubbed this a "Jahn–Teller metal" because when the material is studied using infrared spectroscopy, the fulleride molecules clearly show rugby-ball distortions, which were only known to occur in insulators. However, nuclear magnetic resonance measurements clearly show that electrons are able to "hop" from one molecule to the next – which is the signature of a conducting metal. "An interesting question is how the material can have both Jahn–Teller distortions and be a metal?" says Matthew Rosseinsky of the University of Liverpool, UK, who was involved in the research.
References and links
Paper link: http://advances.sciencemag.org/content/1/3/e1500059
http://physicsworld.com/cws/article/news/2015/may/06/new-state-of-matter-found-in-crystal-made-from-buckyballs
http://www.popularmechanics.com/science/energy/a15501/jahn-teller-metal-new-state-matter/
http://nanotechweb.org/cws/article/tech/61131
Tuesday, March 29, 2016
Concussion & CTE
Have you seen the movie "Concussion"?
If so you might wonder how exactly brain bounces inside the cranial vault during an impact. And what exactly is CTE?
Your brain is a soft organ that is surrounded by spinal fluid and protected by your hard skull. Normally, the fluid around your brain acts like a cushion that keeps your brain from banging into your skull. But if your head or your body is hit hard, your brain can crash into your skull and be injured.
The condition known as chronic traumatic encephalopathy (CTE) was formerly believed to exist primarily among boxers, and was referred to as dementia pugilistica. It is a progressive degenerative disease which afflicts the brain of people who have suffered repeated concussions and traumatic brain injuries, such as athletes who take part in contact sports, members of the military and others.
Chronic traumatic encephalopathy is a condition of brain damage which persists over a period of years or decades and which is the result of traumatic impacts to the cranium.
This fake brain actually has the same consistency as the real deal. So now you know how concussions happen!
Concussions - Read & Learn:http://www.mayoclinic.org/diseases-conditions/concussion/basics/symptoms/con-20019272
Protecting the brain against concussion:
Watch TED Lesson:https://www.ted.com/talks/kim_gorgens_protecting_the_brain_against_concussion?language=en
CTE - Read & Learn:http://www.protectthebrain.org/Brain-Injury-Research/What-is-CTE-.aspx
Corina Marinescu
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