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Jyoti Q Dahiya
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New ways of studying old teeth

In a non-invasive technique, the fossil is scanned, and then 3-D printed. Researchers can wiggle the printout to their hearts' content.

These researchers are trying to find the origins of teeth.

And dentists are starting to 3D print teeth, too.

Convergent evolution?

Via +rasha kamel

#biology #fossilfish #fossilteeth #3dprinting
"Three-dimensional prints of a 400 million year old fish fossil from around Lake Burrinjuck in southeast Australia reveal the possible evolutionary origins of human teeth, according to new research by The Australian National University (ANU) and Queensland Museum.
ANU and Queensland Museum digitally dissected the jaws of a fossil Buchanosteus - an armoured fish from the extinct placoderm group - and used the 3-D prints to learn how the jaws moved and whether the fish had teeth.
Dr Gavin Young, one of the ANU researchers, said the study helped determine when and how teeth - a characteristic feature of all animal species with jaws, including humans - had originated in evolutionary history.
"We have used CT scanning facilities at ANU to investigate the internal structure of very fragile fossil skulls and braincases that have been acid-etched from limestone rock," said Dr Young, a palaeontologist at the ANU Department of Applied Mathematics.
"We are conducting further research on the internal tissue structure of tooth-like denticles in the mouth of the fish fossil, to determine whether they represent a transitional stage in the evolution of teeth."
Co-researcher Ms Yuzhi Hu from the ANU Research School of Earth Sciences said the evolutionary origin of teeth was a major scientific question".
Three-dimensional prints of a 400 million year old fish fossil from around Lake Burrinjuck in southeast Australia reveal the possible evolutionary origins of human teeth, according to new research by The Australian National ...
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Hearing in crickets

Have you ever been maddened by a cricket? (There's one buzzing away in the vicinity right now, so this post is particularly apposite). It's so difficult to locate the miserable insect by ear.

And yet, this is the way they call out for mates. In the dark.

So how do they do it?

The answer is so very cool. I'm expecting some biomimetic applications of this awesome research finding. Can this help in human hearing aids, too?

Via +rasha kamel

#biology #crickets #hearing.
"An incredibly advanced hearing system which enables a group of insects to listen to the same sound twice with each ear, helping them to locate the sound's origin with pinpoint accuracy, has been discovered by scientists at the University of Lincoln, UK.
The new Leverhulme-funded research set out to explore how Copiphora gorgonensis – a bush-cricket native to Colombia, South America – is able to hear sound signals from potential mates and to detect the sound source.
Unlike vertebrates, bush-crickets' ears are located in their forelegs. Each front leg exhibits a single ear below the knee with two eardrums (also known as tympanic membranes), which are backed by a narrow cylindrical tube (the acoustic trachea) running along the leg internally and opening out on the side of the insect's body.
The researchers found that a single sound actually arrives at the bush-crickets' ears twice, at different times and with different amplitudes, using the external and internal paths. The eardrums in each leg receive sound from the external side, and internally via the tracheal tube, making this type of ear a 'pressure difference receiver'. This dramatically improves their ability to locate the sound source.
This significant new discovery helps to explain how these nocturnal insects use their advanced hearing systems to successfully locate their mating partners in the dark.
Dr Fernando Montealegre-Z from the University of Lincoln's School of Life Sciences led the study. He explained: "Our research used advanced technologies to show how these bush-crickets receive sound signals in a way that enables them to detect their original source. We showed that the sound arrives at each tympanal membrane twice; externally at the normal speed of sound in air and then again internally via the acoustic trachea inside the animal, at a slightly slower speed. Curiously, the sound travelling inside the tracheal tubes is also amplified because the tube has the effect of an acoustic horn, a bit like an ear trumpet. Taken together, this means this tympanal membrane is receiving the signal twice – the first time at normal sound speed and with no amplification, and the second time slower but louder".
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Space | Rosetta's last picture

It's so cool that you have an ultra-close up, with one pixel being only 5 mm across. Most space pictures have resolutions no better than 10 meters/pixel (except for the Mars rovers).

I'm greatly surprised to find the pebbles lying there so peacefully. Gravity is a bigger wonder than I previously thought!

Via +Andres Soolo

#space #rosetta #67pCG
From #67P with love: #Rosetta last image of Comet 67P/Churyumov-Gerasimenko, taken shortly before impact at an altitude of 51 m above the surface. The image scale is about 5 mm/pixel and the image measures about 2.4 m across. #cometlanding  

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A new Google thing! Check out the cool Natural History page.

Thanks to +Ganesh Nayak on the Google+ Create: India community for sharing.

Meet the beautiful, the dangerous, the endangered on @GoogleArts #PreviouslyOnEarth
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wow waaaay cool!
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Should religious institutions be exempt from paying tax?

The article gives a very concise and convincing argument why not. It's a USA based article, but applies everywhere. I'd say political parties should not be exempt either, and for the same reasons.
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I've always said that authoritarian governments must get rid of charities because they are the main competition. Not enough people will vote for the government food program if the charities are all giving out food to the poor. So regulate the charities, send around a few health inspectors to close them down, then say, "Vote for me because these charities aren't giving out enough free food!"
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Psychology | Why do some people always blame the victim?

It's to do with their orientation towards individuals and society. And yes, it's real and can be measured.

Incidentally, sometimes victims seem to be blaming themselves when they agonise about what they should have done differently. This is not the same thing. When they try to see what they 'should' have changed, they're trying to regain power over their lives by focussing on the things they can control (what they did) vs what's out of their control (what the criminal did).

The article also talks about an earlier finding, about how the way the crime is reported influences victim-blaming.

Via +Art Markman, who writes on psychology and neuroscientific advances and discoveries. Check out his posts.

#victimblaming #psychology
How does people's moral outlook affect the way they treat crime victims?
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+Bill DeWitt the culture is totally different. In Japan if it happened to you, it is your fault. The circumstances literally do not matter. This is receding in Japan, but it's still literally quite ingrained in the culture, which is big on the binding phenomenon described in the article.

The other extreme, though, is that there is no reflection by the victim on his or her own actions, which is equally unhealthy. It actually is better to take precautions, such as walking with a buddy and sticking with well-lit places with lots of people around.  Would it be better if muggers and rapists didn't exist?  You bet. But that's not the world we live in.
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Space | Rosetta's grave

I have nothing to add to +Elizabeth Therese Niwel's excellent post. Read it and raise a toast to the intrepid comet-chaser that solved so many riddles, and raised its due share.

RIP Rosetta, in the deep cold at the outer edges of the System.

#space #rosetta #67pCG
ESA’s historic Rosetta mission has concluded as planned, with the controlled impact onto the comet it had been investigating for more than two years.

Confirmation of the end of the mission arrived at ESA’s control centre in Darmstadt, Germany at 11:19 GMT (13:19 CEST) with the loss of Rosetta’s signal upon impact.

Rosetta carried out its final manoeuvre last night at 20:50 GMT (22:50 CEST), setting it on a collision course with the comet from an altitude of about 19 km. Rosetta had targeted a region on the small lobe of Comet 67P/Churyumov–Gerasimenko, close to a region of active pits in the Ma’at region.

The descent gave Rosetta the opportunity to study the comet’s gas, dust and plasma environment very close to its surface, as well as take very high-resolution images.

Pits are of particular interest because they play an important role in the comet’s activity. They also provide a unique window into its internal building blocks.

The information collected on the descent to this fascinating region was returned to Earth before the impact. It is now no longer possible to communicate with the spacecraft.

“Rosetta has entered the history books once again,” says Johann-Dietrich Wörner, ESA’s Director General. “Today we celebrate the success of a game-changing mission, one that has surpassed all our dreams and expectations, and one that continues ESA’s legacy of ‘firsts’ at comets.”

“Thanks to a huge international, decades-long endeavour, we have achieved our mission to take a world-class science laboratory to a comet to study its evolution over time, something that no other comet-chasing mission has attempted,” notes Alvaro Giménez, ESA’s Director of Science.

“Rosetta was on the drawing board even before ESA’s first deep-space mission, Giotto, had taken the first image of a comet nucleus as it flew past Halley in 1986.

“The mission has spanned entire careers, and the data returned will keep generations of scientist busy for decades to come.”

“As well as being a scientific and technical triumph, the amazing journey of Rosetta and its lander Philae also captured the world’s imagination, engaging new audiences far beyond the science community. It has been exciting to have everyone along for the ride,” adds Mark McCaughrean, ESA’s senior science advisor.

Since launch in 2004, Rosetta is now in its sixth orbit around the Sun. Its nearly 8 billion-kilometre journey included three Earth flybys and one at Mars, and two asteroid encounters.

The craft endured 31 months in deep-space hibernation on the most distant leg of its journey, before waking up in January 2014 and finally arriving at the comet in August 2014.

After becoming the first spacecraft to orbit a comet, and the first to deploy a lander, Philae, in November 2014, Rosetta continued to monitor the comet’s evolution during their closest approach to the Sun and beyond.

“We’ve operated in the harsh environment of the comet for 786 days, made a number of dramatic flybys close to its surface, survived several unexpected outbursts from the comet, and recovered from two spacecraft ‘safe modes’,” says operations manager Sylvain Lodiot.

“The operations in this final phase have challenged us more than ever before, but it’s a fitting end to Rosetta’s incredible adventure to follow its lander down to the comet.”

The decision to end the mission on the surface is a result of Rosetta and the comet heading out beyond the orbit of Jupiter again. Further from the Sun than Rosetta has ever journeyed before, there would be little power to operate the craft.

Mission operators were also faced with an imminent month-long period when the Sun is close to the line-of-sight between Earth and Rosetta, meaning communications with the craft would have become increasingly more difficult.

“With the decision to take Rosetta down to the comet’s surface, we boosted the scientific return of the mission through this last, once-in-a-lifetime operation,” says mission manager Patrick Martin.

Many surprising discoveries have already been made during the mission, not least the curious shape of the comet that became apparent during Rosetta’s approach in July and August 2014. Scientists now believe that the comet’s two lobes formed independently, joining in a low-speed collision in the early days of the Solar System.

Long-term monitoring has also shown just how important the comet’s shape is in influencing its seasons, in moving dust across its surface, and in explaining the variations measured in the density and composition of the coma, the comet’s ‘atmosphere’.

Some of the most unexpected and important results are linked to the gases streaming from the comet’s nucleus, including the discovery of molecular oxygen and nitrogen, and water with a different ‘flavour’ to that in Earth’s oceans.

Together, these results point to the comet being born in a very cold region of the protoplanetary nebula when the Solar System was still forming more than 4.5 billion years ago.

While it seems that the impact of comets like Rosetta’s may not have delivered as much of Earth’s water as previously thought, another much anticipated question was whether they could have brought ingredients regarded as crucial for the origin of life.

Rosetta did not disappoint, detecting the amino acid glycine, which is commonly found in proteins, and phosphorus, a key component of DNA and cell membranes. Numerous organic compounds were also detected ¬by Rosetta from orbit, and also by Philae in situ on the surface.

“It’s a bittersweet ending, but in the end the mechanics of the Solar System were simply against us: Rosetta’s destiny was set a long time ago. But its superb achievements will now remain for posterity and be used by the next generation of young scientists and engineers around the world.”

While the operational side of the mission has finished today, the science analysis will continue for many years to come.

Overall, the results delivered by Rosetta so far paint comets as ancient leftovers of early Solar System formation, rather than fragments of collisions between larger bodies later on, giving an unparalleled insight into what the building blocks of the planets may have looked like 4.6 billion years ago.

“Just as the Rosetta Stone after which this mission was named was pivotal in understanding ancient language and history, the vast treasure trove of Rosetta spacecraft data is changing our view on how comets and the Solar System formed,” says project scientist Matt Taylor.

“Inevitably, we now have new mysteries to solve. The comet hasn’t given up all of its secrets yet, and there are sure to be many surprises hidden in this incredible archive. So don’t go anywhere yet – we’re only just beginning.”

Read more at:
ESA’s historic Rosetta mission has concluded as planned, with the controlled impact onto the comet it had been investigating for more than two years.
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Still can't help but wonder what it might have been like if they'd nuclear powered them as NASA does.
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The coolest scientific and technological advances of the week

Brought to you by +Mark Bruce.

#medicaltech #physics #materials #cancer
SciTech #ScienceSunday Digest - 39/2016.
Permalink here:

Fixing DNA damage, Modular synbio pellets, Towards head transplant, Custom acoustic holograms, Advanced drone systems, Wireless emotion detection, Atomically precise molecular syntheses, Metastasis gene therapy, Wireless MEMS, Sewing robot.

1. Compensating for DNA Damage
New work by the SENS Research Foundation has successfully achieved stable allotropic expression (in the nucleus), import (into mitochondria), and assembly into functional protein complexes able to rescue the cell and metabolism from mutations in the mitochondrial copies of these genes With some additional work and tricks the group hope the demonstration will allow all 13 mitochondrial genes to be moved to the nucleus and so solve one of the seven causes of aging damage, which will be important for things like sarcopenia In related work human cells engineered to contain a copy of the Dsup gene from tardigrades suffered 50% fewer DNA mutations as a result of prolonged exposure to X-rays; the group hope to discover related protective genes that grant tardigrades their resilience and the possibility is open to gene therapies to reduce DNA mutation rates in humans.

2. Modular DNA Expression Pellets
You can now produce bulk freeze-dried pellets containing the key cellular components needed for translating DNA to proteins - all of the enzymes, ribosomes, tRNA, etc that you need to do this basic protein production process The idea is that you’d have a supply of these pellets (room temp shelf-life > 1 year) and when you needed to conduct a test or produce a protein you’d synthesise your gene or DNA of interest and add it to a pellet in some water. Such cell-free synthesis is an exciting technology, another tiny step towards atomically-precise synthesis, and something that would be immediately useful for remote or at-home applications above and beyond those demonstrated: protein vaccines, antimicrobial peptides, multi-enzyme production for metabolic pathway to create a complex organic drug molecule, antibodies for diagnostics, etc.

3. Towards Human Head Transplant
Recent previous work in mice and recent work in dogs a modified solution of polyethylene glycol has been used to at least partially restore the neural connections in animals whose spines have been almost completely severed In the recent dog experiment the dog apparently regained the ability to walk after about three weeks. Surgeon Sergio Canavero plans to use these result to press forward with the first ever human head transplant next year, using the technique to help reconnect the severed spine of the patient’s head with the donor body. Others demand that at the lack of detailed histology data of the supposedly repaired spinal interface damages the case for proceeding in humans.

4. Custom Acoustic Holograms
Three dimensional acoustic holograms take a big step forward with a new system that uses a single powerful ultrasound transducer onto which is placed a 3D printed block that has been precisely patterned to form an acoustic hologram; ultrasound passing through the block is forced into the desired custom waveform, to levitate objects for example Such a device produces an acoustic hologram with a resolution 100 times greater than previously possible with separate transducer systems. While working in air or water it can’t produce a dynamically changing waveform to move objects, although movement along fixed paths is possible. One possible way around this is to encode multiple sound fields at different frequencies to add some dynamic options.

5. Delivery, Security, Navy, Surveillance Drones
First, a cool new long range delivery drone combines a biplane design with VTOL and fixed-wing capabilities to get the best of both worlds Second, Aptonomy is launching a large security drone to monitor protected areas and intercept tresspassers Third, the Navy’s Blackwing drone platform is designed to be launched by submarine to provide wide-area surveillance and control of other drone and communications assets Finally, DARPA’s Aerial Dragnet system is being designed to provide persistent wide-area surveillance of areas such as cities via networked drone swarms

6. Detecting Emotions with Wireless Signals
EQ-Radio is a system that uses wireless signals and reflections to measure subtle changes in a person’s breathing and heart rhythms in order to determine their emotional state In recent tests the system was able to correctly predict whether the person was excited, happy, angry, or sad 87% of the time. Capturing human emotional states in such a way, particularly when not visibly obvious, would have uses in a wide range of different areas including security monitoring crowded events, entertainment, health care, consumer preferences, etc. The system measures heartbeats as accurately as an ECG monitor with an error margin of 0.3%.

7. Atomically Precise Molecular Chains
The size of alternative atomically precise materials that can be synthesised keeps getting larger with this recent creation of atomically precise gold nanoparticles enshrouded with a functional molecular shell and linked via a precise molecular bridge Progressively building up such units would allow the creation of ever-larger precise crystalline materials with novel electrochemical properties given that the electron clouds of the metal cores become coupled. There are also efforts to build more sophisticated catalysts by precisely combining palladium with ruthenium in different mixed or shelled structures

8. Gene Therapy Stops Cancer Metastasis
A gene therapy technique involving the delivery of microRNAs of a specific sequence into cancer cells is successful in preventing those cancer cells from undergoing metastatic spread through the body These microRNAs specifically regulate and block the expression of the Palladin protein that helps drive metastasis, and was delivered in this case from microRNAs embedded in nanoparticles that were loaded into a hydrogel scaffold that was subsequently implanted into the mice. Such a tool is a viable approach to cancer treatment in combination with other cancer-killing approaches. In related gene editing news, Synthego launches a CRISPR kit for labs and DIYers to make CRISPR editing easier

9. Wireless MEMS
A microelectromechanical device has been built that can be turned on and off with a nanowatt of power from three feet away, with the concept being to use the nanoresonator itself as the antenna for the device The device achieved an efficiency of 15% and the group believes it might find application in optogenetics to provide a route for wireless power and communications to devices implanted in and interfaced to the brain. But such wireless MEMS could be used everywhere: for example a modified router might monitor wireless MEMS sensors placed on movable objects all over the house.

10. A Sewing Robot
Sewbo has launched a robot to automate garment sewing, such as the sewing that typically takes place en masse in sweatshops It doesn’t have the versatile flexibility of human sewing of course, and the key innovation is a method to temporarily hold the garment fabric in solid sheet form (it uses off-the-shelf sewing machines and robotic arms) that can be more easily picked up and guided by automated systems, but which when plunged into warm water removes the polymer to return it back to the soft flexible garment for sale and use. This gets us towards fully automated garment production.

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Space | Another first

This is the first time that an ISRO rocket has put satellites into two different orbits. A lot of young engineers and scientists are super-excited, as one of the satellites was made by students in Pune.

With this, the total load that can be launched by ISRO is going up. The target is to use strap-on boosters and eventually loft 15 Mg at one go.

At that point, Indians shall start dreaming of launching humans. =)

Via +Kam-Yung Soh 

#space   #isro   #satellitelaunch  
"AsianScientist (Sep. 28, 2016) - India on Monday launched weather satellite SCATSAT-1 into orbit from the Satish Dhawan Space Center in Sriharikota. The 371 kg satellite will be used for weather forecasting, typhoon detection and tracking studies.

SCATSAT-1 was carried into polar sun-synchronous orbit (SSO) by India’s Polar Satellite Launch Vehicle-35 (PSLV-C35), which completed its thirty-seventh flight.
This is the fifth mission for PSLV for 2016. The total number of satellites launched by India’s workhorse launch vehicle has now reached 121, of which 42 are Indian and the remaining 79 are from around the world."
The advanced weather satellite will be used in weather forecasting, typhoon detection and tracking studies.
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I'm off G+ for a few days because I have hospital duty with sick relatives.

I'll be baack. 
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"Space, the final front ear!"
Science fiction fan, voracious reader, loves puns, cartoons and pretty photos, and anything sciencey.
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Made it easier for people worldwide to take their spare tyre out of the boot; was the first person to realise software could be sold with advertising (was in print with this before hotmail was launched).
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